TTodays electric grid odays electric grid was designed to was designed to operate as operate as aa
vertical structure consisting of generation, trans vertical structure consisting of generation, trans and dist.
and dist.
Supported with controls and devices to maintainSupported with controls and devices to maintain
reliability ,stability and efficiency reliability ,stability and efficiency
Now operators facing challenges including theNow operators facing challenges including the
penetration of RER , rapid technological changes penetration of RER , rapid technological changes and different types of market players and end
and different types of market players and end users
The next iteration smart grid will The next iteration smart grid will be equippedbe equipped
with communication support schemes on real with communication support schemes on real time measurement techniques to enhance
time measurement techniques to enhance resiliency and
resiliency and forecasting.forecasting.
Protection against internal and Protection against internal and externalexternal
threats. threats.
Framework: based on Framework: based on unbundling andunbundling and
restructuring the power sector and restructuring the power sector and optimizing its assets
New grid: capable ofNew grid: capable of
◦
◦ Handling uncertainties in schedules and powerHandling uncertainties in schedules and power
transfers across regions transfers across regions ◦
◦ Accommodating renewablesAccommodating renewables
◦
◦ Optimizing the transfer capacity of transmissionOptimizing the transfer capacity of transmission
and distribution networks and meeting the demand and distribution networks and meeting the demand for increased quality and reliable supply
for increased quality and reliable supply ◦
◦ Managing and resolving unpredictable events andManaging and resolving unpredictable events and
uncertainties in operations and planning uncertainties in operations and planning
Active consumer Active consumer participation participation Consumers are Consumers are uninformed and do uninformed and do not participate not participate Informed, involved Informed, involved consumers; demand consumers; demand response and response and distributed energy distributed energy resources resources Accommodation of all Accommodation of all generation and generation and storage option storage option Dominated by central Dominated by central generation; many generation; many obstacles exists for obstacles exists for distributed energy distributed energy resources resources interconnection interconnection Many distributed Many distributed
energy resources with energy resources with plug and play- focus plug and play- focus on renewables
on renewables
New products services New products services and markets and markets Limited , poorly Limited , poorly integrated wholesale integrated wholesale markets: limited markets: limited opportunities for opportunities for consumers consumers Mature, well Mature, well integrated wholesale integrated wholesale markets.
markets. Growth Growth ofof new electricity new electricity markets for markets for consumers consumers Provision of power
Provision of power Focus on outages-Focus on outages- Power qualityPower quality –– a a haracteristics
There are many smart There are many smart grid definitions, somegrid definitions, some
functional, some technological, and some functional, some technological, and some benefits-oriented.
benefits-oriented.
A common element to most definitions is theA common element to most definitions is the
application of digital processing and application of digital processing and
communications to the power grid, making communications to the power grid, making data flow and
data flow and information managemeinformation managementnt central to the smart grid.
AA
that uses
that uses information and communicationsinformation and communications
technology
technology to gather and act on information, to gather and act on information, such as information about the
such as information about the behaviors ofbehaviors of suppliers and consumers, in an
suppliers and consumers, in an automatedautomated fashion to improve
fashion to improve the efficiency, reliability,the efficiency, reliability, economics, and sustainability of the
economics, and sustainability of the
production and distribution of electricity production and distribution of electricity
smart grid
Advanced metering infrastructureAdvanced metering infrastructure
Outage management systemOutage management system
Power quality managementPower quality management
Demand responseDemand response
Renewable integrationRenewable integration ––microgridmicrogrid
Smart home energy managementSmart home energy management
Energy storageEnergy storage
facilitates monitoring and facilitates monitoring and measuremeasurement ofment of
consumer information through Smart Meters consumer information through Smart Meters installed at customer premises. The
installed at customer premises. The
information is transferred to utility control information is transferred to utility control centre through communication mode such centre through communication mode such GPRS / PLC / RF. Smart meters will also
GPRS / PLC / RF. Smart meters will also enable Time of Day (TOD)
enable Time of Day (TOD) and Critical Peakand Critical Peak pricing (CPP)/Real Time Pricing (RTP)
pricing (CPP)/Real Time Pricing (RTP) raterate metering and monitoring based on energy metering and monitoring based on energy consumption.
Recording energy consumption data for consumer and Recording energy consumption data for consumer and utilityutility
(kWh, kVARh voltage, pf, max demand
(kWh, kVARh voltage, pf, max demand etc.)etc.)
Automatically send the consumption data to the utility at pre-Automatically send the consumption data to the utility at
pre-defined intervals. defined intervals.
Time-based pricing signal for Demand Response.Time-based pricing signal for Demand Response.
Bi-directional communication ability.Bi-directional communication ability.
Net metering to facilitate integration of Distributed Generation inNet metering to facilitate integration of Distributed Generation in
the form of Roof Top Solar etc. the form of Roof Top Solar etc.
Loss of power (and restoration) event notification.Loss of power (and restoration) event notification.
Remote Load limiting for Peak Load management.Remote Load limiting for Peak Load management.
Remote connection and disconnection of individual supply.Remote connection and disconnection of individual supply.
Energy prepayment.Energy prepayment.
Reporting meter tampering in real time to the utility.Reporting meter tampering in real time to the utility.
Communications with other intelligent devices in the home.Communications with other intelligent devices in the home.
outages of distribution
outages of distribution infrastructure likeinfrastructure like Distribution Transformers (DTs), HT/LT Distribution Transformers (DTs), HT/LT feeders etc. It collect and coordinates feeders etc. It collect and coordinates information about outages including information about outages including
customer calls and report the operator for customer calls and report the operator for taking corrective actions through crew
taking corrective actions through crew manageme
management and nt and remote control enablingremote control enabling customer satisfaction, improve System
customer satisfaction, improve System Availability and
Availability and Reliability.Reliability. OMS
address events like address events like
Voltage flickering (Sags/Swells), unbalanced Voltage flickering (Sags/Swells), unbalanced phases voltages and harmonic
phases voltages and harmonic
distorted/contaminated supply etc. This will distorted/contaminated supply etc. This will facilitate efficient and reliable operation of the facilitate efficient and reliable operation of the power system, reduce losses, improve customer power system, reduce losses, improve customer satisfaction and reduced equipment
satisfaction and reduced equipment
(utility/consumer) failures. Power Quality (utility/consumer) failures. Power Quality management shall include voltage / VAR
management shall include voltage / VAR Control,Control,
Load balancing, Harmonics Controller etc. Load balancing, Harmonics Controller etc. Power Quality Management
The DR application collects The DR application collects information frominformation from
various systems like the
various systems like the load forecast,load forecast,
SCADA, and MDM sub systems. Based on SCADA, and MDM sub systems. Based on these inputs power demand-supply is
these inputs power demand-supply is determined for prese
determined for present and the nt and the next timenext time block and the
block and the deficit/surplus is workedeficit/surplus is worked out.d out. Based on the deficit/surplus demand
Based on the deficit/surplus demand response signa
response signals are sent out to ls are sent out to thethe consumers.
Demand Side ManagemeDemand Side Management solution hnt solution helps toelps to
make the electric grid much more efficient make the electric grid much more efficient and balanced by assisting the consumers and balanced by assisting the consumers
reduce their overall electric demand, and/or reduce their overall electric demand, and/or shifts the time period when they
shifts the time period when they use theiruse their
electricity, and/or prioritizes the way they use electricity, and/or prioritizes the way they use electricity, and in so doing,
electricity, and in so doing, reduces theirreduces their overall energy costs. It also helps utility overall energy costs. It also helps utility inin deferring additional investment in
deferring additional investment in capacitycapacity addition, reductions of AT&C losses.
Demand response (DR) mechanism shallDemand response (DR) mechanism shall
create an understanding among consumers create an understanding among consumers that pricing of
that pricing of electricity varies significantlyelectricity varies significantly during the day, facilitating consumer for
during the day, facilitating consumer for wiser use of electricity. Demand response wiser use of electricity. Demand response includes turning off non essential loads & includes turning off non essential loads &
shifting energy intensive activities to off peak shifting energy intensive activities to off peak hours.
A Microgrid is an integrated energy A Microgrid is an integrated energy andand communication system consisting of
communication system consisting of
interconnected loads and Distributed Energy interconnected loads and Distributed Energy Resources (DER) which mainly operates in
Resources (DER) which mainly operates in standalone mode or in parallel with
standalone mode or in parallel with the gridthe grid
(macro grid) in case of
(macro grid) in case of emergency. Microgridemergency. Microgrid generation resources include Micro turbines, generation resources include Micro turbines, wind, solar, fuel cells or other
wind, solar, fuel cells or other energy sources.energy sources. The multiple dispersed generation sources and The multiple dispersed generation sources and ability to isolate the microgrid from a larger
ability to isolate the microgrid from a larger
network provides highly reliable electric power to network provides highly reliable electric power to its consumers.
TheThe will will
enable the end user to
enable the end user to monitor energymonitor energy consumption & cost
consumption & cost of electricity, optimiseof electricity, optimise energy usage, control appliances and other energy usage, control appliances and other devices, make informed decisions under
devices, make informed decisions under variable pricing structure, participate in variable pricing structure, participate in demand response programs empowering demand response programs empowering consumer involvement in energy
consumer involvement in energy management process.
management process.
Home Energy Management System Home Energy Management System
Growing Electrical power needs for the spaceGrowing Electrical power needs for the space
craft systems-Megawatt range craft systems-Megawatt range
Existing DC based power systems hasExisting DC based power systems has
limitations
limitations –– excessive copper cable weight to excessive copper cable weight to compensate for the losses
compensate for the losses
Early AC power distribution employees solarEarly AC power distribution employees solar
arrays and brayton generator has power arrays and brayton generator has power sources
sources
Rotary transformer Rotary transformer and and series series resonantresonant
inverter to generate high
Capgemini’s Vision:Capgemini’s Vision:
Capgemini believes that in Capgemini believes that in order to makeorder to make
meaningful progress toward addressing the meaningful progress toward addressing the current grid challenges and delivering on the current grid challenges and delivering on the future grid characteristics, utilities should
future grid characteristics, utilities should focus on four main
1.Gather data: Data should be collected 1.Gather data: Data should be collected from many sources onfrom many sources on
the grid. the grid.
2. Analysis/forecasting: The data that is gathered should be 2. Analysis/forecasting: The data that is gathered should be ana-
ana-
lyzed—lyzed—for operational and business purposes.for operational and business purposes.
3. Monitor/manage/act: In the operational world, data that3. Monitor/manage/act: In the operational world, data that
comes from the grid hardware will trigger a predefined process comes from the grid hardware will trigger a predefined process that will inform, log or take action.
that will inform, log or take action.
4. Rebuilding the grid to support bi-directional power flow and4. Rebuilding the grid to support bi-directional power flow and
transfer of power from substation to substation: This is to enabletransfer of power from substation to substation: This is to enable
IBM believes that the smart grid will beIBM believes that the smart grid will be
manifested by a steady progression toward a manifested by a steady progression toward a ―Participatory Network,‖ a t
―Participatory Network,‖ a technologyechnology ecosystem comprising a wide variety of ecosystem comprising a wide variety of intelligent network-connected devices, intelligent network-connected devices, distributed generation, and consumer
distributed generation, and consumer energyenergy manageme
Preparing for an environment in which Preparing for an environment in which customers are more activecustomers are more active
participants.participants.
Capitalizing on new sources of real-time customer andCapitalizing on new sources of real-time customer and
operational information, and deciding which role(s) to play in the operational information, and deciding which role(s) to play in the industry’s evolving value chain.
industry’s evolving value chain.
Better understanding and serving an increasingly heterogeneousBetter understanding and serving an increasingly heterogeneous
customer base.customer base.
To make these improvements, IBM believes that utilities will de-To make these improvements, IBM believes that utilities will
de-ploy advanced energy technologies such as smart metering, ploy advanced energy technologies such as smart metering, sensors and distributed generation.
sensors and distributed generation.
They believe that these technologies respond to the followingThey believe that these technologies respond to the following
interests: interests:
The combination of energy price The combination of energy price increases and consumers’ inincreases and consumers’ in-
-creased sense of responsibility for the impact of
creased sense of responsibility for the impact of their energy usagetheir energy usage on the environment.
on the environment.
The frequency and extent of The frequency and extent of blackouts are driving consumers, poli-blackouts are driving consumers,
poli-ticians and regulators alike to demand assessment and upgrade of ticians and regulators alike to demand assessment and upgrade of the industry’s aging
the industry’s aging network infrastructure.network infrastructure.
Climate change concerns have invigorated research and capacityClimate change concerns have invigorated research and capacity
investments in small, clean
investments in small, clean generating technologies.generating technologies.
Technology costs have generally decreased as lower-cost commu-Technology costs have generally decreased as lower-cost
commu-nications, more cost-effective computing and open standards have nications, more cost-effective computing and open standards have become more prevalent.
For utility executivesFor utility executives——GE believes the potential forGE believes the potential for
dramatic energy productivity gains could improve dramatic energy productivity gains could improve service,
service, control control costs costs and and strengthen reliability.strengthen reliability.
For operations managersFor operations managers——GE anticipates a reductionGE anticipates a reduction
in the frequency and impact of
in the frequency and impact of outages withoutages with improved real-time knowledge of grid status. improved real-time knowledge of grid status.
For chief information technology officersFor chief information technology officers——GE seesGE sees
the smart grid the smart grid
as based on open-standard software andas based on open-standard software and
communication protocols, easing systems integration communication protocols, easing systems integration and support.
For maintenance and For maintenance and engineering professengineering professionals- GE ionals- GE believes morebelieves more
can be done with less, and focuses resources on improving service,can be done with less, and focuses resources on improving service,
instead of simply maintaining it.instead of simply maintaining it.
Accurate, real-time and actionable knowledge of grid status enables a Accurate, real-time and actionable knowledge of grid status enables a
shift from time-based to need-based maintenance. It also allows for a shift from time-based to need-based maintenance. It also allows for a more timely response to
more timely response to outages, speeding power restoration.outages, speeding power restoration.
For customer service (call center) For customer service (call center) functionsfunctions——Calls can be anticipat-Calls can be anticipat-
ed when an outage has occurred, making systems more responsiveed when an outage has occurred, making systems more responsive
to customers. Armed with answers, calls can be resolved faster,to customers. Armed with answers, calls can be resolved faster,
allowing delivery of accurate information and a reduction of call-allowing delivery of accurate information and a reduction of call-
Some major elements GE believes will beSome major elements GE believes will be included are:
included are:
Distributed generation working seamlessly withDistributed generation working seamlessly with current assets.
current assets.
Smart homes that make savings practical andSmart homes that make savings practical and ease facets of every-day life.
ease facets of every-day life.
Demand response that really knows demand andDemand response that really knows demand and optimizes response.
Thermal issues are generally related to Thermal issues are generally related to thermal limits caused, thermal limits caused, change in thechange in the network configuration. In a meshed power system, there can occur a situation network configuration. In a meshed power system, there can occur a situation
where a low impedance line carries much more power than originally designed for, where a low impedance line carries much more power than originally designed for, while parallel paths are underutilized.
while parallel paths are underutilized.
In the future when, among others, private companies will operate In the future when, among others, private companies will operate
transmission lines and sell energy to interested parties, the load flow will transmission lines and sell energy to interested parties, the load flow will have to be controlled. One possibility is to use HVDC lines; another
have to be controlled. One possibility is to use HVDC lines; another possibility is load flow control using FACTS devices in an AC network; possibility is load flow control using FACTS devices in an AC network;
• Voltage and reactive power control issues—• Voltage and reactive power control issues—low voltage at heavily loadedlow voltage at heavily loaded transmission lines as well high voltage at lightly loaded lines are
transmission lines as well high voltage at lightly loaded lines are undesirable occurrences in transmission lines.
undesirable occurrences in transmission lines.
The first can be a limiting factor responsiblThe first can be a limiting factor responsible for reduced value of the transmittede for reduced value of the transmitted power and the second can cause equipment damage.
power and the second can cause equipment damage.
The corrective actions with utilization of selected FACTS devices include correctingThe corrective actions with utilization of selected FACTS devices include correcting the power factor and compensating reactive losses in lines by supplying reactive the power factor and compensating reactive losses in lines by supplying reactive power;
Loss reduction— Loss reduction—generally, total losses in agenerally, total losses in a system cannot be reduced to such an extent
system cannot be reduced to such an extent thatthat
the installation of power flow controllers is the installation of power flow controllers is justified.
justified.
Only the losses due to reactive Only the losses due to reactive power flow, whichpower flow, which usually are quite small, are easily avoidable. A
usually are quite small, are easily avoidable. A reduction of the losses due to active power flow reduction of the losses due to active power flow
would require a decrease of the
would require a decrease of the line resistances.line resistances. However, loss reduction in a
However, loss reduction in a particular area ofparticular area of the system is a relevant issue.
Power transfers from one point to another willPower transfers from one point to another will
physically flow on a number of parallel paths and physically flow on a number of parallel paths and thereby impel losses on lines that might belong to thereby impel losses on lines that might belong to another utility, thus causing increased costs for
another utility, thus causing increased costs for thatthat company. If the latter utility cannot accept these
company. If the latter utility cannot accept these losses, power flow control can be a solution;
losses, power flow control can be a solution;
Transient and dynamic stability control issuesTransient and dynamic stability control issues——
transient stability describes the ability of the power transient stability describes the ability of the power system to survive after a major
system to survive after a major disturbance, whiledisturbance, while dynamic stability describes sustained or growing dynamic stability describes sustained or growing power swing oscillations between generators or a power swing oscillations between generators or a
group of generators initiated by a disturbance (fault, group of generators initiated by a disturbance (fault,
The first phenomenon can be improved byThe first phenomenon can be improved by
synchronizing power flow between sending synchronizing power flow between sending
and receiving ends. and receiving ends.
A solution for the second phenomenon lies in A solution for the second phenomenon lies in the use of equipment that
the use of equipment that permits dynamicpermits dynamic damping of such oscillations.
damping of such oscillations.
In the first as well as the secondIn the first as well as the second
situation, active power flow control can be a situation, active power flow control can be a solution.
Delivery of power at multi kHz Delivery of power at multi kHz frequency viafrequency via
electric cables electric cables
◦
◦ Flexibility to meet loads at different voltage levelsFlexibility to meet loads at different voltage levels
◦
◦ Ease of electrical isolation using compact high freqEase of electrical isolation using compact high freq
transformers transformers ◦
◦ Savings in component and system integrationSavings in component and system integration
◦
◦ Improves the dynamic response of the systemImproves the dynamic response of the system
◦
◦ Reduces acoustic noiseReduces acoustic noise
Development in high frequency cable and
Development in high frequency cable and magneticmagnetic materials ,resonant power converter technologies materials ,resonant power converter technologies Advanced Soft Switching schemes
High frequency operationHigh frequency operation –– higher EMI and higher EMI and
higher cross talk higher cross talk
Design of power cables that carry highDesign of power cables that carry high
frequency current without significant skin and frequency current without significant skin and proximity effect losses
proximity effect losses
Cable must also have low inductive reactanceCable must also have low inductive reactance
to minimize voltage drop and
to minimize voltage drop and radiatedradiated magnetic fields
HFAC system for space application proposedHFAC system for space application proposed
by Sood and Lipo by Sood and Lipo
Pulse density modulation called areaPulse density modulation called area
comparison pulse density modulation to comparison pulse density modulation to control the amplitude of the power output control the amplitude of the power output
This refers to minimization of voltThis refers to minimization of volt –– time time
area, difference between the reference signal area, difference between the reference signal and the synthesized output signal
and the synthesized output signal
The circuit aims to produce the correctThe circuit aims to produce the correct
proportion of positive and negative half cycle proportion of positive and negative half cycle pulses
High brid or double tuned resonant inverterHigh brid or double tuned resonant inverter
was developed. was developed.
Aims to meet the steady state operatingAims to meet the steady state operating
requireme
requirement of a nt of a power source for thepower source for the
international space station mobile servicing international space station mobile servicing system
system
The key requirements are high efficiency atThe key requirements are high efficiency at
varying load, good voltage regulation and low varying load, good voltage regulation and low harmonic distortion
Present power distributionPresent power distribution –– DC domain DC domain
Higher power Higher power requirementrequirements s - - HigherHigher
complexity
complexity –– higher reliability higher reliability –– compactness compactness –– challenges for DC distributions challenges for DC distributions
Two types of power distributionTwo types of power distribution –– centralized centralized
DC / DC and distributed DC/DC DC / DC and distributed DC/DC
The first method simple to The first method simple to implementimplement –– for a for a
single DC/DC converter
single DC/DC converter, converting 48 , converting 48 VoltsVolts battery input to
battery input to different voltagedifferent voltagess
The current to be distributed in bus bar isThe current to be distributed in bus bar is
very high very high
Results in Results in larger larger conductors conductors - - Excessive Excessive heatheat
–– voltage drop voltage drop
