Application systems:
The main MicroSCADA-based application systems are:
1. Substation Automation System for Power transmission
distribution substation
2. Network Control and DMS for Power distribution
Substation Automation system:
Substation Automation means that the substation has equipment, which enables communication with the primary equipment and use of process data for
supervision, control and communication. The function may include:
viewing status of breakers and disconnectors controlling the breakers and disconnectors
MicroSCADA is a microcomputer-based, programmable and distributed supervisory control and data acquisition (SCADA) system.
Microcomputer-based:
MicroSCADA programs run on commercially available PC-computers.
Programmable:
All MicroSCADA application programs as well as most system configuration programs are built in SCIL - Supervisory Control Implementation Language.
Distributed system:
The system can be regarded as a network where the control system can communicate with the widely distributed process through a communication system.
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dynamic coloring of the bus bars
viewing and setting of protection parameters
viewing condition of auxiliary equipment e.g. batteries collection of metering data
Transferring data to network control center (S).
Network Control System:
Network control that a geographically widely distributed process is supervised and controlled from a central control office.
Network control of power distribution means remote control of:
• power networks
• substations and secondary substation
The basic functionality is supervisory control and data acquisition (SCADA) including at least:
• process status overviews and process control
• Data collection and handling historical reports.
In addition, a network control application may include user authorization, viewing and setting of protection parameters, bus bar coloring function etc.
Supervision:
MicroSCADA lets the operator supervise the process interactively with schematic pictures which illustrate the real process and direct the operator to make correct decision.
Control:
The operator performs control operations-open, close, lower, higher, etc by activating function keys, dialogs and windows.
Data acquisition:
Process information is stored on a process database and a report database.
The real-time process database stores incoming and outgoing process data signals. Process communication from and to the base system passes through the process database.
The report database stores historical data and mathematically or statistically handled values. It also executes SCIL programs based on time or events.
Distribution management System:
Distribution management provides the tools to handle the distribution network and quickly locate and eliminate disturbances and faults.
The basic distribution management functions are:
• network coloring
• fault location
• Operation simulation.
The network coloring function presents the distribution process as a topological map of the network.
Additional distribution management functions are e.g. load flow calculation, loss minimization and security analysis.
Operational features:
MicroSCADA provides:
• a picture-oriented operator technique
• on-screen function keys, dialogs and windows
• a reporting system that supports advanced calculation
• access to all process and system data, which is limited by user rights
• simultaneous supervision of several processes on one screen or several screen
• on-line programmability (i.e. user systems can be extended and adjusted during normal operation)
• Possibilities to simulate processes and control operation.
9. Time ripe for automation....
Distribution Automation is anytime a pragmatic solution for a prime distribution firm like NDPL to gratify its esteemed customers to fetch the sense of reliability from that side.
Existing distribution systems have certain inherent inefficiencies due to their legacy. For one, most systems are monitored manually. This results in
maintenance taking place only during breakdowns. The present system also does not ensure reliable and complete power system and usage information that can facilitate trend forecasting or help the utility in better analysis and planning.
At places, the billing systems are still unreliable. While the present system has intensive manpower requirement and over-dependence on experts, it is still a logistic nightmare to reach remote locations. Even trouble-shooting in case of breakdowns is based on the conventional call system through
telephone answering machines.
...but there are hurdles
Although many utilities are talking to distribution automation vendors, this has not taken off the way it should have. There are two reasons. First, the cost factor. The cost of a complete distribution automation system for a major city is Rs 30-50 crore.
Another limiting factor could be the quality of existing communications network. Distribution automation systems require reliable communication media from control centre to field equipment -- through telephone cable, microwave, optic fibre, etc. In the absence of efficient telecommunications infrastructure, the creation of a complete communication system may add up to around 30 per cent of the total project cost. This may be higher in case of an optic fibre network. The implementation of OFC broadband network by ASPs in different cities can help the utilities to use it for automating
distribution.
The future
There is an imperative need for solutions to optimize efficiencies within the existing system. Globally, distribution automation by utilities has shown that it pays for itself in a very short span of time.
Already, there is a growing realization in India that SCADA systems will have a significant impact on distribution control applications and the way enterprises manage, or will manage, their business to stay competitive.
Quite of few of the SEBs and most of the newly formed distribution
companies are increasingly looking at SCADA to provide solutions ensuring efficient distribution of power across their respective territories, despite financial and communications infrastructure constraints.
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