Rev 1 14/4/2010. Rev 2.30/01/2013_E

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PowerFactory V14

Basic Software Features & Calculation Functions

Advanced Functions and Features

Protection Coordination * Distribution Network Optimization * Harmonic Analysis * Optimal Power Flow

Reliability Analysis* State Estimation * Dynamic Modelling (DSL) * System Dynamics (RMS / EMT)

Motor Starting * Real-Time Simulation* Small Signal Stability * Interfacing PowerFactory * Installation Options

Rev 1 14/4/2010

PowerFactory V14

Basic Software Features & Calculation Functions

Advanced Functions and Features

Protection Coordination * Distribution Network Optimization * Harmonic Analysis * Optimal Power Flow

Reliability Analysis * State Estimation * Dynamic Modelling (DSL) * System Dynamics (RMS / EMT)

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T a b l e o f C o n t e n t s

Table of Contents

1 Introduction ... 6

2 PowerFactory Overview ... 8

2.1 Functional Integration and Applications ... 8

2.2 PowerFactory Software Concept ... 8

3 Network Models ... 11

3.1 Grid Representations and Power Equipment ... 11

3.2 Built-in Calculation and Integrated Modelling Functions ... 15

3.3 Load and Generation Profiles ... 15

4 Data Management ... 16

4.1 V14 Standard Data Model ... 16

4.1.1 Arrangement of Data in Project Folders ... 16

4.1.2 Study Time ... 17

4.2 Data Organisation ... 17

5 Network Diagrams & Graphic Capabilities ... 19

6 Results and Reporting ... 22

6.1 Text Reports ... 22

6.2 Spreadsheet Reports (Tabular Views) ... 22

6.3 Reporting in Network Diagrams ... 23

6.4 Result File Management ... 23

6.5 Plots and Diagrams ... 23

6.6 Additional Features ... 25

7 External Data Format Support ... 26

7.1 Standard Data Formats ... 26

7.2 DIgSILENT Data Base Level Exchange (DGS)... 26

8 DPL- DIgSILENT Programming Language ... 27

9 PowerFactory Modes of Operation ... 29

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9.2 Engine & Hybrid Execution Mode ... 29

10 Power Flow Analysis ... 30

11 Fault Analysis ... 33

11.1 Supported Standards ... 33

11.2 Complete Method/Multiple Faults ... 34

11.3 Fault Analysis Results (all Methods) ... 35

12 Network Reduction ... 36

12.1 General Features ... 36

13 Voltage Stability Analysis ... 37

13.1 PV Curves ... 37

13.2 Q-V Analysis ... 37

14 Load Flow Sensitivities ... 38

15 Contingency Analysis ... 39

16 Overhead Line and Cable Parameter Calculation ... 41

16.1 Overhead Line Parameter Calculation ... 41

16.2 Cable Parameter Calculation ... 41

17 Distribution Network Analysis ... 42

17.1 Feeder Analysis ... 42

17.2 Low-Voltage Network Analysis ... 42

17.3 Stochastic Load Modelling ... 42

17.4 Cable Reinforcement Optimization ... 43

17.5 Feeder Tools ... 44

18 Protection Functions ... 45

18.1 Protection Model Library and Functionality ... 45

18.2 Output & Graphical Representation ... 47

18.3 Overcurrent-Time Protection ... 48

18.4 Distance Protection ... 49

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19.2 Open Tie Optimization ... 50

20 Harmonic Analysis Functions ... 52

20.1 Harmonic Load Flow ... 52

20.2 Frequency Sweep ... 53

20.3 Ripple Control Signals ... 54

20.4 Filter Rating ... 54

21 Optimal Power Flow ... 55

21.1 AC Optimization ... 55

21.2 DC Optimization ... 56

22 Reliability Analysis ... 58

22.1 Failure Models ... 58

22.2 State Enumeration ... 59

22.3 Failure Effect Analysis ... 59

22.4 System Indices and Results ... 60

22.5 Special Features ... 62

22.5.1 High Flexibility ... 62

22.5.2 Tracing of Individual Cases ... 62

22.5.3 Powerful Output Tools for Result Representation ... 62

22.5.4 Contribution to Reliability Indices ... 63

22.5.5 Development of Indices over Years ... 63

23 State Estimation ... 64

24 Dynamic Modelling Flexibility (DSL) ... 66

25 Power System Dynamics ... 68

25.1 General Capabilities ... 68

25.2 Stability Analysis Functions ... 71

25.2.1 RMS Simulation with a-b-c Phase Representation ... 71

25.2.2 Long-term Stability ... 71

25.3 Transient Motor Starting ... 72

25.4 Electromagnetic Transients (EMT) ... 73

25.5 Dynamic System Parameter Identification ... 74

25.6 PowerFactory Real-Time Simulators ... 74

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27 PowerFactory Interfaces ... 78

27.1 DGS Interface ... 78

27.2 OPC Interface ... 78

27.3 Shared Memory Interface ... 79

28 Interfacing PowerFactory ... 81

28.1 PowerFactory - GIS integration ... 81

28.2 PowerFactory - SCADA integration ... 83

28.3 PowerFactory - Simulation Interface (SIMULINK, etc.) ... 84

28.4 PowerFactory - A/D Signal Interfacing Capability ... 84

29 PowerFactory Installation Options ... 85

29.1 PowerFactory Workstation License ... 85

29.2 PowerFactory Server License ... 86

29.3 License Overview ... 90

29.4 Installation Requirements ... 90

30 PowerFactory Function Definitions and Prices ... 91

30.1 PowerFactory Function Definitions ... 91

30.2 PowerFactory Prices ... 92

31 The DIgSILENT Company ... 93

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1 I n t r o d u c t i o n

1

Introduction

DIgSILENT has set standards and trends in power system modelling, analysis and simulation for more than 25 years. The proven advantages of the PowerFactory software are its overall functional integration, its applicability to the modelling of generation-, transmission-, distribution- and industrial grids, and the analysis of these grids’ interactions.

Electrical grids, planning processes and operation processes are becoming increasingly complex due to market unbundling, expansion of interconnections and distributed generation. This increases the demands on software tools in terms of data quality, flexibility and manageability.

With PowerFactory Version 14, DIgSILENT presents a further step towards seamless integration of functionality and data management within a multi-user environment. The building and organizing of schemes, scenarios, versions and running arrangements has been added for improved handling.

Version 14 Key Features

• Single- and multi-user project data administration environment • Database with historical data storage and auditing functionality. • Time-stamped data model

• Management of operational scenarios

• Baselining, versioning and publishing of models

• Integrated node and branch, and switch and component modelling • Integrated overview diagrams, simplified and detailed single line diagrams • Fast contingency analysis tools (AC and DC load flow)

• Contingency-constrained economic dispatch including quad booster optimization • Distributed/embedded power generation modelling

• New models for wind power and virtual power plants

DIgSILENT PowerFactory is the most economical solution, as data handling, modelling capabilities and overall functionality replace a set of other software systems, thereby minimizing project execution costs and training requirements. The all-in-one PowerFactory solution promotes highly-optimized workflow.

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1 I n t r o d u c t i o n

DIgSILENT PowerFactory is easy to use and caters for all standard power system analysis needs, including high-end applications in new technologies such as wind power and distributed generation and the handling of very large power systems. In addition to the stand-alone solution, the PowerFactory engine can be smoothly integrated into GIS, DMS and EMS supporting open system standards.

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2 P o w e r F a c t o r y O v e r v i e w

2

PowerFactory Overview

2.1

Functional Integration and Applications

• Implemented as a single software solution allowing for fast 'walk around' through the database and execution environment

• No need to reload modules and update, transfer and convert data and results between different program applications

• Vertically integrated power equipment model concept allowing models to be shared by all analysis functions

• Support of transmission-, distribution- and industrial system design and simulation • Modelling and simulation of railway systems

• Simulation of any kind of wind turbines and wind parks

• Smart Grid modelling including virtual power plants and distributed generation such as PV-panels, micro turbines, battery storage, CHP, etc.

2.2

PowerFactory Software Concept

Single Database Concept

• Optimal data organization and project definitions for performing any type of calculation, storage of settings, diagrams and visualization options or software operation sequences.

• No need for tedious organization of several files for defining the various analysis aspects and project execution workflows.

• Database environment fully integrates all necessary data, such as that required for defining cases, scenarios, variants, single-line graphics, outputs, run conditions, calculation options, graphics or user-defined models. Saving a project includes everything required to rerun all user-defined cases at a later stage. • Access to all data via a comfortable and powerful data manager, object browser, plus various types of

diagrams and wizards.

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User Roles

• Access to user information through a user accounting system • Protection of data through different types of access rights

• Folder sharing between users with “read-only” access. This is especially useful for libraries and network base cases which should be administrated only by authorized personnel.

Multi-User Operation and Team working

• Multi-user data administration supporting MS-SQL or ORACLE databases

• Support of user accounting, access rights and data sharing, featuring the powerful option of allowing several users to work on the same project in a coordinated way. This demonstrates the concept of non-redundant data management in PowerFactory..

• Management of multi-user data editing via the definition of a base project, project versions and derived projects (virtual projects).

• Support of version control including rollback functions and merge/compare tools.

Network Variations, Expansion Stages Management and Operational Scenarios

• Support of time-stamped network variations. • Variation scheduler for easy handling of sub-projects • Definition of study cases and operational scenarios

• Activation of network stages according to study time. This automatically addresses the handling of power system components according to their commissioning and de-commissioning dates

Multi-Level Models

• Data describing network models such as cables, machines, loads, transformers, etc., are subdivided into element data and type data which point to libraries.

• All data to be entered are grouped into basic data (data required for all calculations) and function level data (data required only for executing specific calculations).

• Data are simply entered in physical quantities rather than in per unit values, minimizing the need for manual recalculation and conversion of data.

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• Integrated calculators for asynchronous machines, cable data and tower configurations

Batch Mode, Engine Mode and Interfaces

• Fully interactive windowing mode according to the latest, proven standards • Engine mode for background operation

• Various communication features to exchange data with other applications such as GIS, SCADA and real-time control systems via OPC, shared memory, DGS (CSV, ODBC), etc.

• Hybrid operation switching between background and windowing mode according to users’ needs • Data exchange via CIM, PSS/E, UCTE and many other file formats

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3 N e t w o r k M o d e l s

3

Network Models

3.1

Grid Representations and Power Equipment

Grid Models

• Meshed and radial AC systems with 1-, 2-, 3-, and 4-phases • Meshed and radial DC systems

• Combined AC and DC system modelling • Model validity from LV up to ultra-high voltage

Phase Technologies

• Single phase with/without neutral • Two-phase with/without neutral • Bi-phase with/without neutral • Three-phase with/without neutral

Substations

• Simple terminal models to be used for “node and branch” representation, marshalling panels, terminal blocks, terminal strips, clamping bars, joints and junctions.

• Complex substation models with the provision of various standard busbar configurations such as single- and double busbars with/without tie-breakers, bypass busbars, 1½ busbar systems and flexible busbar configurations according to user-specific needs.

• Templates for holding any type of user-specific busbar configuration, including pre-configured protection schemes

Generators and Sources

• Synchronous and asynchronous generator • Doubly-fed induction generator

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• External grid • AC voltage source • AC current source

• 2-terminal AC voltage source

Loads

• General load model (for HV and MV-feeders)

• Complex load model (for feeders with a large number of induction motors) • Low voltage load (can be assigned across line and cable sections)

Reactive Power Compensation

• Static Var Compensator (SVC)

• Shunt/Filter (RLC, RL, C, RLCRp, RLCCRp)

Branch models

• Overhead line and cable models (π-models and distributed parameter models) • Circuits and line sub-sections

• Mutual data, line couplings, tower geometries • 2-, 2-N-winding transformer and auto transformer • 3-winding transformer, booster transformer

• Series reactor, series capacitor and common impedance

DC Models

• 1-terminal and 2-terminal DC voltage source and DC current source • DC/DC converter

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Power Electronics Devices

• Thyristor/Diode converter models

• Self-commutated converter models (VSC-converter) • DC valve (for building individual converter topologies) • Softstarter

Switches and Substation Equipment

• Circuit Breaker and Disconnector • Load-Break-Disconnector • Load-Switch

• Grounding Switch • Fuse

• NEC/NER, grounding devices • Surge arrester

Composite Models

• Composite node models, e.g. representing complex substations • Composite branch models

• Template library for handling composite models

Parameter characteristics

• Time characteristics and discrete characteristics • Scalar, vector and matrix characteristics • File references and polygons

• Continuous and discrete triggers • Frequency and time scales

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Controllers

• Station controller, secondary controller (SCO), virtual power plant • Tap controller, shunt controller

• User-definable capability diagrams and controllers

Organisation and Grouping

• Site, station, substation, area, zone • Feeder, branch, bay

• Operator, owner • Boundaries

Operational Library

• Substation running arrangements • CB ratings

• Thermal ratings

• Library of faults/contingencies • Library of (planned) outages

Others

• Protection relays with over 30 basic protection function blocks

• Manufacturer-specific relay library with relay models from all major manufacturers • CT, VT and various measurement transducers (P, Q, f, etc.)

• Fourier source, harmonic source, FFT

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PowerFactory supports 500 different objects for defining, organizing and storing users’ grid definitions and project settings. The above-listed objects are a summary of those most frequently used.

3.2

Built-in Calculation and Integrated Modelling Functions

PowerFactory provides a number of functions which assist users in entering data which may have come from datasheets or product catalogues. Not only do these functions greatly simplify data entry, but they also provide valuable output and results.

Identification of asynchronous machine parameters

• Support of two different parameter input modes: (a) electrical parameters and (b) slip-torque/current characteristic

• When entering electrical parameters, such as the rated mechanical power, stator resistance and reactance, magnetisation reactance, etc., all electrical parameters which precisely define and describe the asynchronous machine are then calculated. This includes the determination of the torque-/speed characteristic.

• The alternative definition via the slip-torque/current characteristic requires entering data such as characteristics at nominal operation point, torque at stalling point, locked rotor torque and other parameters typically available from manufacturer handbooks or test reports. This alternative data entering method will then determine the electrical machine parameters.

Calculation of Overhead Line Parameters and Cable Parameters

Please refer to section 16.

3.3

Load and Generation Profiles

• Load and generator parameter characteristics can be defined on a per-element basis for parametric studies. Parameter characteristics can be imposed on each input parameter. They may be time-dependent, refer to predefined discrete cases, or result from external sources.

• All operational data (generation and demand patterns, switch positions, etc) can be saved and maintained in distinct Operation Scenarios.

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4 D a t a M a n a g e m e n t

4

Data Management

4.1

V14 Standard Data Model

4.1.1

Arrangement of Data in Project Folders

All data required for grid modelling, project organization and project execution are arranged in project folders. Project data are structured into Libraries, Network Models, Operation Scenarios and Study Cases.

Libraries

• Libraries contain equipment types, special operation information, DPL scripts, templates and user-defined models.

• The Equipment Type Library can store manufacturer and standard data for cables, conductors, circuit breakers, transformers, motors, generators, protection devices, PV panels, converters, wind turbines, etc.

• Operational Libraries help organize standard settings and operational structures of grids. Typical entries include specific device Mvar limits and capability curves, outages, fault conditions and sequences, specific thermal ratings, running arrangements, etc.

Network Models

• All network data are organized and stored in various folders such as grid- and area folders, folders for boundaries, circuits, feeders, routes, zones, etc.

• Comprehensive network topology handling defining: Nodes, Substations, Sites, Boundaries, Circuits, Routes, Operators and Owners.

• Graphical information such as overview diagrams, simplified single line diagrams and detailed single line diagrams are automatically organized in a separate diagram folder

• Grid Variations are linked to the original grid data, allowing non-redundant grid variation

management.

• Easy and non-redundant handling of grid expansion alternatives.

• Planned grid expansions are organized by time-stamped Expansion Stages which are considered depending on the selected Study Time. Expansion Stages are stored in Variations and handled via the

Variation Scheduler. In other words, variations can be seen as expansion plans composed of

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Operation Scenarios

• Definition of operation and dispatch conditions, grid loading, ambient temperature, daily load variation pattern, etc

• Organisation of characteristics to generate ranges of values such as daily load curves, temperature dependencies, wind conditions, solar radiation pattern, etc

• Definition of triggers for easy selection of certain conditions to be analysed • Comparison of Operation Scenarios

Study Cases

• Grid configurations, operation conditions, trigger settings, calculation options, fault sequences, results and DPL scripts to be executed are all stored in Study Cases

• Study Cases can be activated to reproduce any grid condition and its associated calculation results

4.1.2

Study Time

PowerFactory V14 extends grid modelling into the dimension of time. The model may span a period of months or years considering network expansions, planned outages and other system events. The period of validity of a project therefore specifies the time span that the of the model’s validity.

• The Study Time automatically determines which expansion stages of a variation will be considered. • Selection of Study Time along with the operational conditions will automatically create grid expansion

scenarios

4.2

Data Organisation

Simultaneous use of grid data takes place when two different parties work with the same project. This kind of situation occurs most frequently in larger companies where software-based teamworking capabilities are a basic requirement.

Versioning

• Project Versions constitute a snapshot of a project at a specific point in time

• Project versions are under full control of owner rights

• Rollback functions allow a controlled “Undo” of a project’s execution steps, thereby “rolling back” to a

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• Reporting facilities for Derived Projects which depend on a certain version

Derived Projects

• Master Projects can be published in a public area of the database

• Derived Projects are “virtual” copies of a Version of a Master Project that can be developed by any number of users simultaneously. Only the differences to the original version are stored

• Derived Projects are always linked to their original Master Project

• The users will be automatically notified if a new version of their Master Project is available

• Comprehensive tools for merging several derived projects and/or their versions into a new project via the Merge Tool. This allows the consolidation of independent and parallel model modifications introduced by different users.

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5 N e t w o r k D i a g r a m s & G r a p h i c C a p a b i l i t i e s

5

Network Diagrams & Graphic Capabilities

Categories of Network Diagrams

• Simplified Single Line Diagrams with various options for a schematic view of substation topology

and switching status

• Detailed Single Line Diagrams showing all switches (circuit breakers and disconnectors)

• Intelligent Overview Diagrams providing a node and branch representation of the network. Can be schematically, geographically or semi-geographically arranged

General Features

• Handle mixed representations of Detailed Single Line Diagrams, Simplified Single Line Diagrams and Overview Diagrams

• Access equipment editing menus in the single line diagram via cursor selection of the appropriate element, region or composite model

• Zoom-in or zoom-out of area networks or composite model graphics

• Initiate calculation events directly within the graphical environment, including circuit breaker switching, fault implementation and other data changes

• Option to immediately reflect any editing activity on the graphical level

• Display any calculation results immediately in result boxes in single line diagrams. All program variables and signals can be displayed according to a highly flexible user definition for various object categories and analysis functions

• Display any calculation result to be defined on various functional levels and categories for any object • Insert freely-configured result displays

• Provision of auxiliary graphics editing for enhanced documentation • Perform copy/paste operation on single objects and groups

• View and operate several graphic windows with different layers and grid sections simultaneously. Utilize several graphical representations of the same system simultaneously.

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• Support of pre-defined and user-defined graphical layers

• Placement of user-definable icons as buttons for executing DPL scripts. This way users can create custom panels of frequently-executed DPL-initiated commands.

Colouring of Network Diagrams

• Provision of various colouring modes according to topology criteria such as areas, zones, owners, operators, routes, station connectivity, energizing status, boundaries/interior regions, isolated grids, etc. • Colouring options to display voltage levels, equipment loading and operation ranges

• Define colouring based on AC/DC equipment category and phase technology

• Display of grid modifications and variants, recording of expansion stage modifications, missing grid connections

• Provision of feeder colouring and path definitions

• User-defined filters based on complex equations or DPL scripts

User-definable Symbols

• Support of user-definable symbols based on standard graphical formats (.wmf,.bmp). E.g. use your own symbols for wind turbines, PV panels, hydro units, etc.

• Define specific graphical representations for transformers, shunts, circuit breakers, isolators to fit individual needs.

Composite Graphics

• Elements can be grouped together and stored as Composite Graphics. Typical applications are standard busbar arrangements, switchboard configurations, HVDC structures, PV panels, typical wind turbine configurations or complete wind parks.

• Composite Graphics can be easily handled via the Template Manager. Templates can be populated with type and element data. For drawing Composite Graphics, the Template Manager is operated as Drawing Tool Box.

Virtual Instruments

• DIgSILENT PowerFactory applies the concept of Virtual Instruments (VI) as a tool for displaying any calculated result or variable.

• Results may be displayed in the form of bar graphs, plotted curves, or even tables of values, with all of these representations being completely user-definable.

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• VIs are used to display protection curves, harmonics analysis results or to view electrical variables from any location in the network single line diagram, and any model variable during RMS and EMT

simulations.

• Many VIs provide additional built-in functionality such as curve labelling and measuring, scaling, curve fitting, filtering and digitizer functions.

Typical Virtual Instruments Available

• x-t and x-y plots, bar diagrams, harmonic distortion diagram

• Overcurrent-time-diagrams, distance-time diagrams, vector diagram, path diagram • Voltage sag diagram, waveform diagram

• Eigenvalue diagram, phasor diagram

• Bitmaps, buttons, DPL-command buttons, digital display • Curve-digitizing diagram

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6 R e s u l t s a n d R e p o r t i n g

6

Results and Reporting

6.1

Text Reports

Automatic reports for calculation results, such as load flow, short-circuit, harmonic calculations, contingency calculation, reliability analysis, etc.

• Numerous predefined reports for all key calculation functions • Flexible selection of elements for reporting

• Reports can be user-configured allowing user-definable formatting

Automatic reports for documentation of network components, such as transformers, lines, generators, relay settings, etc.

• Flexible selection of network components for documentation

• Flexible selection of calculation module, e.g. report only input data required for load flow and short-circuit

6.2

Spreadsheet Reports (Tabular Views)

• Numerous predefined spreadsheet reports for all key calculation functions via “Flexible Data Pages” • User-definable setup of “Flexible Data Pages”. Tabular view of any combination of input parameters/

calculation results

• Several “Flexible Data Page” definitions (variable selections) may exist concurrently • Independent variable selections for every calculation

• Sorting facilities for tabular views

• Automatic statistical summaries for values in tables • Flexible filters for selecting elements for output

• Output facilities to: Output window, clipboard and clipboard with column headers for use in spreadsheet programs such as MS Excel

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6.3

Reporting in Network Diagrams

• Concept of “result boxes” in network diagrams to flexibly display any element/type parameter, as well as any calculation result

• Easy-to-configure “result box” format on both component and calculation levels

6.4

Result File Management

More complex calculation results can be stored in “Result Files”, e.g. for calculations such as transient stability results, harmonic analysis results, contingency results, etc.

• Allows easy configuration of outputs (plots, reports, etc…) • Accessible by post-processing through DPL

• Export functionality to export result data to: - Output window

- Clipboard (compatible with spreadsheet programs such as MS EXCEL) - Text file (compatible with spreadsheet programs such as MS EXCEL) - COMTRADE (for transient data)

- PowerFactory measurement file (ASCII)

6.5

Plots and Diagrams

• DIgSILENT PowerFactory applies the concept of Virtual Instruments (VI) as a tool for visualizing calculation results as plots and diagrams.

• VIs are used to display (for example):

- Results of RMS and EMT simulations (any pre-selected monitoring variable/signal)

- Protection configurations and results (R-X diagrams, automatic time-distance diagrams, relay characteristics, etc)

- Harmonic analysis results

• Many VIs provide additional built-in functionality such as curve labelling and measuring, scaling, curve fitting, filtering and digitizer functions.

Selected List of Most Common Virtual Instruments:

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- Monitored variables/signals over time - Trajectories

• Harmonics

- Harmonic distortion diagram - FFT diagrams

- Waveform plots • Protection

- Time-overcurrent diagrams - Time-distance diagrams - Relay characteristic diagram

• Additional diagrams for results of load flow, short circuit, harmonics, etc.: - Bar diagrams

- Vector diagrams - Path diagram - x-y diagrams • Voltage sag diagram • Eigenvalue calculation

- Eigenvalue diagram

- Phasor diagrams and bar diagrams (controllability, observability, participation) • Measurement VIs

- Digital display

- Metering device (vertical/horizontal scales) - Combination of both

• Picture box for displaying graphic files. Supported file formats are: - Windows metafiles (*.wmf)

- AutoCAD graphic file (*.dxf) - Bitmaps (*.bmp)

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6.6

Additional Features

The PowerFactory graphic windows such as the single line graphic, plots, and block diagrams, offer the following functionality:

• Printing or plotting to any device supported by the Windows Print Manager to produce high quality graphical documents from within the program.

• Export to standard file formats such as:

- Windows Metafile (*.wmf) with high precision coordinates - Bitmap (*.bmp)

• Conversion of graphic files between several file formats such as *.png, *.dxf, *.gif, *.tiff, *.eps, etc. This is achieved via an external tool which is shipped with PowerFactory.

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7 E x t e r n a l D a t a F o r m a t S u p p o r t

7

External Data Format Support

7.1

Standard Data Formats

In many cases, migration of data from other power system software is required. PowerFactory therefore supports foreign file Import of several versions from the following software packages:

• PSS/E, PSS/U and PSS/Adept (Siemens)

• DVG and UCTE (ucte.org)

• NEPLAN (BCP)

• ISU (SAP, billing data)

• NETCAL (STZ Konstanz), NEPS ( I+P Consult) and ReticMaster (Inspired Interfaces)

Foreign file Export is supported for PSS/E and UCTE.

CIM object and format definitions are increasingly used for standardized data exchange. Although the CIM

standards are still under development, PowerFactory already supports CIM import and export: • CIM 61970 (CIM for Transmission)

7.2

DIgSILENT Data Base Level Exchange (DGS)

DGS is PowerFactory’s standard bi-directional interface specifically designed for bulk data exchange with other applications such as GIS and SCADA, and for example, for exporting calculation results to produce Crystal Reports, or to interchange data with any other power system software. DGS (“DGS”=DIgSILENT-GIS-SCADA) does not feature the exchange of PowerFactory execution commands.

• User-specific definition of objects and object parameters

• Supported objects: elements, types and libraries, graphics and results

• Import and export of complete network models as well as incremental data for updating existing models • Database support for: Oracle, MS-SQL and ODBC System DSN

• File formats supported: ASCII Text (CSV), XML, MS-Excel and MS Access

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8 D P L - D I g S I L E N T P r o g r a m m i n g L a n g u a g e

8

DPL- DIgSILENT Programming Language

The DPL-Programming Language offers a flexible interface for automating PowerFactory execution tasks. The DPL scripting language adds a new dimension to PowerFactory software by allowing the implementation of new calculation functions. Typical examples of user-specific DPL-scripts are:

• Parametric sweep calculations (e.g. sliding fault location, wind profile load flows)

• Implementation of user-specific commands (e.g. transfer capability analysis, penalty factor calculation) • Automatic protection coordination and device response checks

• Specific voltage stability analysis via PV-/QV-curve analysis, etc. • Contingency screening according to user-specific needs • Verification of connection conditions

• Data pre-processing including input/output handling • Equipment sizing and dimensioning

• Report generation

The DPL object-oriented scripting language is intuitive and easy to learn. The basic set of commands includes: • C++- like, object-oriented syntax

• Flow commands such as "if-then-else", "do-while" • Input/import, output/export and reporting routines • Mathematical expressions, support of vectors and matrices

• Access to any PowerFactory object and parameter including graphical objects • Definition and execution of any PowerFactory command

• Object filtering and batch execution

• PowerFactory object procedure calls and DPL subroutine calls

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8 D P L - D I g S I L E N T P r o g r a m m i n g L a n g u a g e

Easy Development

DPL’s basic syntax allows for the quick creation of simple high-level commands to automate tasks. Such tasks may include renaming objects, search and replace, post-processing calculation results and creating specific reports.

Transparency

All parameters of all objects in the network models are accessible. DPL can be used to query the entire database and to process all user-input and result parameters without restrictions.

Standardizing Commands

The DPL language can be used to create new 'standardized' DPL commands that can be used over and over again. DPL commands allow input parameters to be defined, and can be executed for specific selections of objects. Proven DPL commands can be safely stored in DPL command libraries and be used from there without the risk of damaging the scripts.

Control

DPL commands can configure and execute all PowerFactory commands. This includes not only the load flow and short-circuits calculation commands, but also the commands for transient simulation, harmonic analysis, reliability assessment, etc. New objects can be created by DPL in the database, and existing objects can be copied, deleted and edited. New reports can be defined and written to the output window; new graphs can be created and existing graphs can be adjusted to reflect a user-defined selection or the current calculation results.

Modularity

A DPL command may contain other DPL commands as subroutines. This modular approach allows the execution of subroutines as independent commands. Existing commands can be combined to quickly create more complex commands.

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9 P o w e r F a c t o r y M o d e s o f O p e r a t i o n

9

PowerFactory Modes of Operation

9.1

Standard Windowing Mode

9.2

Engine & Hybrid Execution Mode

The standard execution of DIgSILENT PowerFactory is via the classical windowing mode operated via mouse and keyboard. When operated in “Engine Mode” PowerFactory is executed as a background process featuring a number of additional application options:

• Bi-directional, high-speed exchange of data via “DIgSILENT Shared Memory Interface” or via “OPC” (OLE for Process Control). When using OPC, PowerFactory is executed as an OPC-Client.

• Remote-execution of any PowerFactory command including activation of projects, modification of data, execution of analysis functions and DPL scripts, generation of output and reports, etc.

• Temporary activation/popup of the “Windowing Mode” featuring interactive windowing operation until the windowing mode is closed and the engine mode resumes (“Hybrid Operation Mode”).

In principle, a number of additional application features may be operated as background processes in situations where it is integrated into GIS/NIS or SCADA systems or linked with other simulation tools such as

Matlab/SIMULINK, ASPENTECH’s process simulation tool or other software systems requiring interaction with network analysis procedures. The engine mode also features parallel processing with other PowerFactory processes.

The “Engine Mode” permits the remote control of all PowerFactory functions with fast data and execution command exchange.

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1 0 P o w e r F l o w A n a l y s i s

10

Power Flow Analysis

Within the Load Flow analysis environment, the accurate representation of a variety of network configurations and power system components is possible.

• DIgSILENT PowerFactory offers a selection of calculation methods, including a full AC Newton-Raphson technique (balanced and unbalanced) and a linear DC method. The enhanced non-decoupled Newton-Raphson solution technique with current or power mismatch iterations, typically yields round-off errors below 1 kVA for all buses. The implemented algorithms exhibit excellent stability and convergence. Several iteration levels guarantee convergence under all conditions, with optional automatic relaxation and modification of constraints. The DC load flow, solving for active power flows and voltage angles, is extremely fast and robust (linear system; no iterations required).

• Any combination of meshed 1-, 2-, and 3-phase AC and/or DC systems can be represented and solved simultaneously, from HV transmission systems, down to residential and industrial loads at LV voltage levels. Neutral conductors can be modelled explicitly.

• The Load Flow tool accurately represents unbalanced loads, generation, grids with variable neutral potentials, HVDC systems, DC loads, adjustable speed drives, SVSs and FACTS devices, etc., for all AC and DC voltage levels.

• DIgSILENT PowerFactory offers a new, intuitive and easy-to-use modelling technique which avoids the definition of bus types such as SL, PV, PQ, PI, AS, etc. PowerFactory simply provides the control mechanisms and device characteristics which are found in reality.

More Load Flow Analysis Features

• Consideration of reactive power limits: detailed model for generator Mvar capability curves (including voltage-dependency).

• Practical station control features with various local and remote control modes for voltage regulation and reactive power generation. Reactive power is automatically adjusted to ensure that generator output remains within its capability limits.

• Various active power control modes, e.g. as dispatched, according to secondary or primary control, or inertial response.

• Supports device characteristics, such as voltage-dependent loads and asynchronous machines with saturation and slip dependency, etc.

• Comprehensive area/network power exchange control features using Secondary Controllers (SCO) with flexible participation factors.

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• Transformer OLTC able to control local or remote bus voltages, reactive power flows and voltage-drop compensation (LDC) within distribution systems. Special transformer controller model for parallel transformers. Transformer tap adjustment supports discrete and continuous methods.

• Device controllers for shunts, doubly-fed asynchronous machines and other power electronics elements such as self-commutated converters (VSC), thyristor/diode converters or integrated FACTS devices. • Local and remote control mechanisms for SVCs. Automatic and continuous control of TCR and TSC

switching is performed within component ratings to hold the voltage at a given value. • Correct representation of transformer vector groups and phase displacement.

• Shunts can be modelled to consist of a combination of series and/or parallel connected capacitors, reactors and resistors. Shunts can be connected to busbars and feeders or to the remote ends of cables and lines. Filters may consist of any number of shunt combinations, and automatic shunt switching can be included in the automatic voltage regulation.

• Support of the Virtual Power Plant model for generator dispatch based on merit order algorithm. • Feeder load scaling to control power flows at feeder entry point – including nested and parallel feeders. • Full support of any parameter characteristic and scale to allow parametric studies or easy definition of

loading scenarios or load profiles.

• All operational data (generation and demand patterns, switch positions, etc) can be saved and maintained in distinct Operational Scenarios.

Further Special Functions

• Analysis of system control conditions • Consideration of protection devices • Determination of ‘Power at Risk’

• Calculation of Load Flow Sensitivities. Evaluation of expected active/reactive power flow and voltage changes in the network based on the effect of demand/generation or transformer tap change. • Support of DPL scripts; e.g. to perform load balancing, determination of penalty factors or any other

parameter required.

Load Flow Results

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• Various colouring modes for the single line graphic to visualize quantities such as calculated loading and/or voltage levels

• Detailed analysis reporting, which can list overloaded system elements, unacceptable bus voltages, system islands, out-of-service components, voltage levels, area summaries, and more

• Detailed textual output with pre-defined or user-defined filters and levels • DPL interactivity with all results

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1 1 F a u l t A n a l y s i s

11

Fault Analysis

DIgSILENT PowerFactory features fault calculation functionality based on international standards as well as the most accurate DIgSILENT General Fault Analysis (GFA) method.

The following features and options are supported by all implemented fault analysis methods: • Calculation of fault levels at all busbars.

• Calculation of short-circuit quantities at a selected busbar or along a defined section of line/cable, including all branch contributions and busbar voltages

• Calculation of all symmetrical components as well as phase quantities. • User-definable fault impedance

• Provision of specially designed graphs and diagrams including all quantities typically required by the protection engineer

• Thermal overloads highlighted on the single line graphic for busbars and cables, with all equipment overloads available in a summary text report

• Calculation of Thevenin impedances as seen from the faulty node

• Calculation of apparent phase impedances (magnitude and angle) at any location along a transmission line/cable or busbar, for all branches, selected subsets thereof, or 1, 2 or 3 nodes from the faulted node

11.1

Supported Standards

IEC 60909 and VDE 0102/0103

PowerFactory provides a strict and complete implementation of the most frequently used standard for component design world-wide; the IEC 60909 and VDE 0102/0103 fault calculation standard, according to the most recently published versions.

• Calculation of the initial symmetrical peak current Ik" and short-circuit power Sk", peak short-circuit

current ip, symmetrical short-circuit breaking current Ib, and thermal equivalent current Ith (IEC 60909-0

2001). Both minimum and maximum short-circuit currents can also be calculated based on network voltage c-factors

• Support of all fault types (three-phase, two-phase, two-phase to ground, single-phase to ground) • Calculation of I with selectable “Decaying Aperiodic Component”

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• Selectable method for calculating the peak short-circuit current in meshed networks • User-definable fault impedance, conductor temperature and c-voltage factor.

• Fault calculation can optionally include or exclude motor contribution to the fault current

• Provision of specially designed graphs and diagrams required by the protection engineer for protection coordination and design

IEEE 141 / ANSI e 37.5

PowerFactory provides a thorough implementation of the IEEE 141/ANSI e37.5 fault calculation standard according to the latest published version. Special features are:

• Transformer tap positions can be included in the fault current calculation

• User-defined fault impedance and pre-fault voltage can be included in the fault current calculation

Other Standards

G 74 and IEC 61363

11.2

Complete Method/Multiple Faults

DIgSILENT PowerFactory’s Complete Method is especially designed for protection coordination purposes or for analyzing observed system contingencies. It provides the required algorithms and precision for determining the “true” or “operational” short-circuit currents without considering the simplifications or assumptions typically made in standard fault analysis.

In addition to the high precision network model, multiple faults which occur simultaneously in the system or unusual fault conditions such as inter-circuit faults or single-phase interruptions can be analysed.

• The Multiple Fault Analysis executes a complete network analysis based on subtransient and transient representations of electrical machines taking into account all specified network devices with their full representation and pre-faulted load conditions.

• Combination with IEC60909 principles for the calculation of aperiodic components and peak short-circuit currents

• Calculation of peak-break and break-RMS currents

• Consideration of a complete multi-wire system representation. Applicable to single-phase or two-phase networks.

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• Calculation of any asymmetrical, single or multiple fault condition with or without fault impedance, including single- and double-phase line interruptions.

11.3

Fault Analysis Results (all Methods)

PowerFactory offers many reporting options, including detailed reporting on all short-circuit levels for all faults, or alternatively, a specific report for a particular fault type. Special protection reports can also be generated to include impedance, current and voltage information.

• Display of any variable within the single line graphic, station diagram and Flexible Data Page • Fully flexible filter mechanisms to display objects in colour mode

• Detailed analysis reporting, which can list overloaded system elements, unacceptable bus voltages, system islands, out-of-service components, voltage levels, area summaries and more

• Detailed text output with pre-defined or user-defined filters and levels • DPL interactivity with all results

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1 2 N e t w o r k R e d u c t i o n

12

Network Reduction

The typical application of the network reduction tool is a project where a specific network has to be analyzed but cannot be studied independently of a neighbouring network of the same or of a higher or lower voltage level. In this case, one option is to model both networks in detail for the calculation. However, there may be situations in which it is not desirable to perform studies with the complete model; for example when the calculation time would increase significantly, or when the data of the neighbouring network is confidential. In such cases it is good practise to provide a representation of the neighbouring network which contains the interface nodes (connection points) which may be connected by equivalent impedances and voltage sources.

The objective of Network Reduction is to calculate the parameters of a reduced AC equivalent of part of a network, as defined by a boundary. This boundary must completely split the network into two parts. The equivalent network is valid for both load flow and short-circuit calculations. ,Following this, a model variation can be optionally created in the PowerFactory database, whereby the full representation of the portion of network that has been reduced is replaced by the equivalent.

12.1

General Features

• Flexible definition and maintenance of network boundaries. Various features such as colouring of boundaries and topological checks

• Network Reduction can be calculated at any appropriate boundary

• Support of Standard Ward (PQ-equivalent), Extended Ward (PV-equivalent) and equivalent loads • Support of short-circuit equivalents for transient, subtransient, peak-make and peak-break currents • The reduced network can be created in a network variation. This allows for simple comparison and

swapping between reduced and non-reduced cases.

• Robust reduction algorithms based on the sensitivity approach, i.e. reduced network matches for the current operating point as well as for network sensitivities

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1 3 V o l t a g e S t a b i l i t y A n a l y s i s

13

Voltage Stability Analysis

13.1

PV Curves

PowerFactory supports the calculation of PV curves by applying specifically implemented scripts. These scripts perform the calculation of voltage variations against:

• Load variation in a selected area

• Load shift across boundaries (keeping the total load constant)

• Generator shift across boundaries (keeping the total generation constant)

PV curves can be calculated for a selected set of contingencies. Diagrams are automatically created.

13.2

Q-V Analysis

For analyzing the required reactive power reserve at individual busbars, PowerFactory provides scripts for the calculation of Q-V curves.

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1 4 L o a d F l o w S e n s i t i v i t i e s

14

Load Flow Sensitivities

Supplementing PowerFactory’s voltage stability analysis suite is the Sensitivity Analysis tool. It is often required to not only know the critical point of a system, but also how this critical point is affected by changes in system conditions. PowerFactory’s Sensitivity Analysis tool performs a static voltage stability calculation according to the following options:

• Sensitivity to a single busbar (calculation of the voltage sensitivities of all busbars and branch flow sensitivities according to variations in power (∆P and ∆Q) at the selected busbar).

• Option to calculate sensitivities with respect to all busbars simultaneously.

• Sensitivity to a transformer tap position change (calculation of the voltage sensitivities of all busbars and branch flow sensitivities according to changes of a transformer/quad booster tap).

• Modal analysis

- Identification of “weak” and “strong” parts of the network based on modal transformation of the ∂v/∂Q sensitivity matrix.

- Eigenvalue calculation on the ∂v/∂Q sensitivity matrix, with a user-defined number of eigenvalues to be calculated.

- Results of eigenvalues are displayed (in descending order according to magnitude), and branch/bus sensitivities can be displayed for each mode.

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1 5 C o n t i n g e n c y A n a l y s i s

15

Contingency Analysis

The new Contingency Analysis tool in DIgSILENT PowerFactory has been designed to offer a high degree of flexibility in configuration, calculation methods and reporting options. Single- and multiple- time-phase

contingency analyses are available, both of which offer automatic or user-defined contingency creation based on events, and the consideration of controller time constants and thermal (short-term) ratings.

Calculation Options for Contingency Analysis:

• Support of three calculation methods: - AC load flow calculation - DC load flow calculation

- Combined DC/AC calculation; i.e. full DC load flow calculation and automatic recalculation of critical contingencies by AC load flow

• Single- and Multiple- Time-Phase calculations. Multiple time-phase contingency analysis facilitates user-defined post-fault actions within discrete time periods.

• Generator Effectiveness and Quad Booster Effectiveness calculation:

This calculation feature assists the planner in defining appropriate measures for overstressed

components in critical contingency cases: During contingency analysis, the possible impact of individual generator re-dispatch or transformer tap changes on overstressed lines is evaluated. Corresponding reports are available that list the generator and quad booster effectiveness on a per-case basis. • Ultimate Performance via Grid Computing: Possibility to perform the contingency analysis calculation in

parallel (on multi-core machines and/or clustered PCs)

Management of Contingencies/Fault Cases:

• User-friendly definition of contingencies (n-1, n-2, n-k, busbar) as ‘Fault Cases’ supporting user-defined events to model post-fault actions (re-switching, re-dispatching, tap adjustment, load shedding) • Clustering of ‘Fault Cases’ into ‘Fault Groups’ for efficient data management

• Special Operational Libraries to manage ‘Fault Cases’ and ‘Fault Groups’ for future re-use

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1 5 C o n t i n g e n c y A n a l y s i s

Result File Management:

• Recording of results in (sparse) result file; accessible for any kind of export and/or customer-specific post-processing

• Predefined and user-definable monitoring lists for recording of results; selection of individual

components, component classes and their associated variables to be recorded. Any available calculation result for a standard load flow calculation is accessible during contingency analysis.

• User-defined limits for recording of results (thermal loadings, voltage limits, voltage step change)

Reports:

A wide range of standard reports is available, facilitating summary views or the presentation of results on a per-contingency basis:

• Maximum Loadings Report

• Loading Violations (per case) Report • Voltage Ranges Report

• Voltage Violations (per case) Report

• Generator and Quad Booster Effectiveness Report Other key features:

• Tracing Facilities: Use of the new ‘Trace’ function to step through events in a multiple time-phase contingency, while viewing updated results in the single-line graphic

• Support of component-wise Short-Term Ratings based on pre-fault loading and post-fault time • Special “Contingency Analysis” toolbar for user-friendly configuration, calculation and reporting

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1 6 O v e r h e a d L i n e a n d C a b l e P a r a m e t e r C a l c u l a t i o n

16

Overhead Line and Cable Parameter Calculation

DIgSILENT PowerFactory incorporates the automatic calculation of the electrical parameters of any

cable/overhead line configuration starting from layout and geometric characteristics which are typically available in manufacture’s datasheets. The calculation is applicable over a wide range of frequencies and supports the step-up process of highly accurate line and cable models for harmonic analysis, frequency sweep and EMT-simulation among others. The supported options are described below.

16.1

Overhead Line Parameter Calculation

• Any combination of line circuits (1-, 2- and 3-ph), neutral conductors and earth wires, with/without automatic reduction of earth wires

• A flexible definition of tower types and tower geometries, including conductor sags, allowing a multiple combination of tower geometries and conductor types that avoids entry of redundant data

• Circuit-wise, symmetrical and perfect transposition and user-defined phasing for the definition of any non-standard transposition scheme

• Solid and tubular conductor types, including sub-conductors for phase circuits and earth wires • Skin effect

• Equivalent impedance and admittance matrices in natural, reduced and symmetrical components

16.2

Cable Parameter Calculation

• Multi-phase single core and pipe type cable systems

• Flexible definition of cable layouts, including conducting, semi-conducting and insulating layers • Compact and hollow core shapes, filling factor for stranded conductors

• Consideration of skin effect

Calculation of layer impedances and admittances in natural, reduced and symmetrical components, including sheath and armour reduction, cross-bonding

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1 7 D i s t r i b u t i o n N e t w o r k A n a l y s i s

17

Distribution Network Analysis

17.1

Feeder Analysis

• Feeder Plots: Graphical display feature (Virtual Instrument, VI) to increase transparency in grid loading and voltage profile analysis along the feeder. Displayed result variables are freely configurable. Full interactivity is given via the VI to access all relevant data of the components belonging to the feeder. • Schematic Visualization of Feeder: Automatic generation of single line diagram to visualize components

of the feeder with distance/index view.

• Feeder Load Scaling: A load flow calculation feature that allows the automatic adjustment of individual bus loads to match a specified total feeder load. The selection of loads which are to participate in the feeder scaling procedure is user-defined. This method allows for complex scaling scenarios with nested and parallel feeders.

17.2

Low-Voltage Network Analysis

PowerFactory integrates enhanced features designed especially for the analysis of LV networks. These functions enable the user to:

• Define loads in terms of numbers of customers connected to a line • Consider load diversity

• Perform a load flow analysis that considers load diversity for calculating maximum voltage drops and maximum branch current

• Perform cable reinforcement optimization to either automatically reinforce selected cables, or to provide a report of recommendations

• Perform voltage drop and cable loading analysis

• Perform statistical calculations of neutral currents caused by unbalanced single-phase loading and load diversity, to represent a realistic network

17.3

Stochastic Load Modelling

On the basis of defined ‘customer units’ the user may specify a number of customers connected to a line. Load flow options are provided to define the load per unit customer according to:

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• Power per customer unit • Power factor

• Coincidence factor for an infinite number of loads (i.e. ‘simultaneity factor’)

In addition, the user may select one of two methods for considering the stochastic nature of loads: • Stochastic evaluation (theoretical approach, also applicable to meshed networks)

• Maximum current estimation (application of stochastic rules for estimating maximum branch flow and maximum voltage drops)

The Load Flow with stochastic load modelling then provides maximum currents for each branch component, maximum voltage drops, and minimum voltages at every bus bar..

The usual variables for currents and voltages in this case represent average values of voltages and currents. Losses are calculated based on average values; the maximum circuit loading is calculated using maximum currents.

17.4

Cable Reinforcement Optimization

PowerFactory’s Cable Reinforcement Optimization determines the most cost-effective option for upgrading overloaded cables. The objective function is to minimize annual costs for reinforcing lines (i.e. investment, operational costs and insurance fees). Constraints for the optimization are the admissible voltage band and cable loading limits for the planned network.

• Optimization along pre-definable feeder

• User-definable library of available cable/OHL types with costs that can be used for reinforcement • Consideration of:

- Admissible voltage band limits

- Maximum voltage drop limit at the end of the feeder - Maximum admissible Cable/OHL overloading • Various plausibility checks for final solution

• Calculated results: report of the recommended new cable/overhead types for lines and cost evaluation for the recommended upgrading

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17.5

Feeder Tools

The PowerFactory Feeder Tools comprise a set of tools for radial systems to change voltage levels, phase technology or to optimize phasing from a particular point downwards.

Voltage and Phase Technology Change Tool

• Automatic change of the voltage level and/or phase technology inside a pre-defined feeder • Automatic replacement of type data (for transformers, lines, loads and motors) according to

pre-configurable type mapping tables – including automatic creation of new compatible types if necessary

Auto-Balancing Tool

• Automatic balancing of feeders such that voltage unbalance at terminals is minimized • Reconfiguration of phasing of loads, lines, or transformers and combinations thereof • Supports fixed phasing elements

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1 8 P r o t e c t i o n F u n c t i o n s

18

Protection Functions

The basic functional model library of DIgSILENT PowerFactory’s protection analysis tool has been extended to include additional devices such as CTs, VTs, relays, fuses and more complex protection schemes including user-defined modelling capabilities. Additionally, there are specially designed interactive VIs (Virtual Instruments) for displaying system quantities and, more importantly, for modifying protection settings in the graphical

environment. This last feature is especially useful, as coordinated settings between different protection schemes can be modified via the cursor in the graphical environment, following which the settings in both the database and the simulation environment are also updated.

All protective devices are fully-functional under steady-state and transient conditions, allowing device response assessment under all possible simulation modes, including load flow calculation, fault analysis, RMS and Instantaneous Values (EMT) simulation.

PowerFactory’s main protection features are: • Extensive relay database

• Accurate steady-state relay checking via short-circuit and load flow (balanced & unbalanced) • Precise dynamic relay checking with RMS and EMT simulations

• Consideration of current transformer saturation • Diagrams for overcurrent and distance coordination:

o Time-overcurrent diagrams

o R-X characteristic diagrams

o Time distance diagrams

• Automatic Protection Coordination Wizard for time-overcurrent protection schemes

18.1

Protection Model Library and Functionality

The DIgSILENT PowerFactory protection analysis tool contains a comprehensive protection device model library. All relays are modelled for steady-state calculations (short-circuit, load flow), RMS and EMT simulation modes. The definition of relay types is highly flexible via block diagrams. For RMS and EMT simulation purposes, relays may be extended and adopted to cope with user specific requirements via the PowerFactory DSL language The features of the protection model library are listed below.

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Fuses are represented by their melting curves. It is possible to take minimum and maximum melting curves into

account.

Time-Overcurrent Relays for 1-phase, 3-phase, ground and negative sequence time over-currents.

Additionally, the relay characteristics can incorporate the following standards and solution methods: • IEC 255-3, ANSI/IEEE and ANSI/IEEE squared

• ABB/Westinghouse CO (Mdar)

• Linear approximation, Hermite-spline approximation

• Analytical expressions via built-in formula editor and analyzer (DSL)

Instantaneous Overcurrent Relays for 1- phase, 3-phase, ground and negative sequence time over-currents. Directional Relays for overcurrent, power, ground current, and any combination of time and instantaneous

overcurrent relays. Additionally, voltage and current polarization is used for the detection of negative and zero sequence components considering also dual polarization. Optional: with voltage memory.

Distance Relays for phase, ground and zone distance protection. Provision is available for incorporating

overcurrent and under-impedance starting units (U-I or Z) as well as angle under-impedance. Different characteristics are available for distance relay zones including:

• MHO, offset MHO

• Polygonal, offset polygonal • Tomatoes, lens and circle • R/X Blinders and quadrilateral Support of various polarizations such as:

• Self-polarized

• Cross polarized (90ø connection) • Positive, negative sequence polarized • Optional: voltage memory

Zero sequence and parallel line compensation

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Additional devices such as: Breaker Fail, Motor Protection, Generator Protection, Differential

Protection, Reclosing Relays, Low Voltage Circuit Breakers, and Out-of-Step Relays.

In addition to these protection functions and relays, DIgSILENT PowerFactory provides further devices and characteristics for more detailed protection system modelling, such as:

• Current and voltage transformers that include saturation effects

• Conductor, cable damage curves, cable overload curves and inrush peak current modelling

• Transformer damage curves (ANSI/IEEE Standard C57.109-1985) and inrush peak current modelling • Motor starting curves, cold and hot stall, in-rush peak current modelling, and any user-defined curves All protection device models are implemented within the composite model frame environment. This allows users to easily design and implement their own models, by utilizing the graphical user interface for constructing block diagrams.

18.2

Output & Graphical Representation

Time-Overcurrent Diagrams

- Overcurrent curve adjustment using drag & drop - Display of tripping curve tolerances during drag & drop - User-defined labels

- Tripping times are automatically displayed for calculated currents in time-overcurrent diagrams - Display of an unlimited number of overcurrent curves in diagrams

- Simple creation and addition of diagrams via single line graphics

- Display of motor starting curves, conductor/cable and transformer damage curves - Balloon help showing name of relay, etc.

- Double-click on curves to change relay settings - Additional axis for voltage levels

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- Display branch impedances with several options - Automatic display of calculated impedances - Adding relays with offset

- Flexible display of zones (starting zones, etc.) Time Distance Diagrams

- Different methods for calculating curves: kilometrical or short-circuit sweep method - Forward and/or reverse diagram

- Selectivity check of distance and overcurrent relays/fuses in same diagram - Separate overreach zone representation

- Additional axis showing relay locations and busbars/terminals

- Selectable x-axis scaling (length, impedance, reactance, 1/conductance) Single Line Diagram

- Colouring of switches according to relay locations, relay tripping times - Display of relay tripping times in result boxes

- Additional text boxes for relay settings Relay Setting Report

Relay Tripping Report

18.3

Overcurrent-Time Protection

The coordination of overcurrent-time protection is performed graphically using the current-time diagram as the basis. Relay settings are modified using drag & drop to move characteristics. Short-circuit currents calculated by the short-circuit command, are shown in the diagram as a vertical line. In addition, the corresponding tripping times of the relays are displayed. Coordination between relays at different voltage levels is available. Therefore, currents are automatically based on the leading voltage level, which can be selected by the user.

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18.4

Dis