a*star funded ieds project - microgrid energy management...
TRANSCRIPT
A*STAR Funded IEDS Project -Microgrid Energy Management System
by
H B GOOI
4 Aug 2009
Outline
● Introduction - Distributed Generators and Microgrids
● Proposed Microgrid Energy Management System (MEMS)
● MEMS at Lab for Clean Energy Research (LaCER), NTU
● Possible IES Project Idea - Integrating Thermal & Electrical Energy System
Centralized Generation● Usually very large capacity generators over hundreds of MWs
● Usually located far away from load centers
● Waste heat discharged into rivers or sea
●● Low energy conversion efficiency: 30 - 40%
Distributed Generation●●●●●●●● Usually very small capacity generators: a few kWs to a few MWs
●●●● Usually located at load centers - can avoid T&D cost & losses
●●●● Waste heat can be recovered for heating & cooling
●●●● High energy conversion efficiency: over 80% with CCHP
●●●● Emerging: renewables such as solar, wind, marine, etc
Microgrids
● Microgrids are low voltage networks, which include loads, energy
storage systems, and several small distributed modular generation systems, providing both power and heat
● Microgrids can operate in isolated or interconnected mode
Benefits
● Improve efficiency by combined heat and power (CHP)● Improve efficiency by combined heat and power (CHP)
● Enhance local reliability, improve power quality, and provide
lower costs of energy supply, etc
Other potential societal benefits
● Protect vital public utilities
● Offer a place for integrating small-scale renewables (reduce
emissions)
Singapore Power System
●●●● High voltage network 66 kV and above
●●●● Medium voltage network 22
kV and 6.6 kV
●●●● Low voltage network 400 V
●●●● Energy Management System
(EMS) manages 66-kV, 230-
kV and 400-kV generation
and transmission system
●●●● Distribution Management
System manages 22-kV and
6.6-kV distribution system
Singapore Market Operation
Key players
●●●● Regulator (EMA)
●●●● Power system operator (PSO)
●●●● Market operator (EMC)
●●●● Electricity retailers
●●●● Gencos
Transco (SP PowerGrid)●●●● Transco (SP PowerGrid)
●●●● Market support services
●●●● Wholesale electricity traders
●●●● Contestable consumers
●●●● Non-contestable consumers
MEMS would enable non-contestable consumers to participate in the market as a single entity.
Is Singapore Ready for Microgrid?
● Government support and its national policy framework
● Energy research at institutions and universities
● Global cry on CO2 emission and demand for energy efficiency
● Deregulated power market and its promotion by the government
● Advanced telecommunication infrastructures
● Software and hardware capabilities● Software and hardware capabilities
● More firms choose to own DGs in the form of trigeneration (CCHP), e.g. pharmaceutical plants of Pfizer and Schering Plough
● Industrial parks, science parks, HDB residential blocks could serve as launching pads
What MEMS Can Offer?
–– All loads in district are All loads in district are aggregated aggregated
–– Renewable and Renewable and traditional generation traditional generation systems CHP, CCHPsystems CHP, CCHP
–– Central control of heat Central control of heat and air conditioningand air conditioningand air conditioningand air conditioning
–– MEMS would collect MEMS would collect data and make data and make decisions for control & decisions for control & optimizationoptimization
What MEMS can offer?
Features
– The MEMS will be responsible for decisions
• When to commit and dispatch each generator
• When to store energy
• Purchase and sale with upstream networks
• Manage load priority and security of microgrid• Manage load priority and security of microgrid
– Incorporate renewable sources and control DERs
– Combined electricity, hot water and air conditioner (district cooling) loads
– Handle offers/bids submitted by DGs and price responsive elastic loads
– Participate in the wholesale energy and reserve market.
Microgrid Energy Management System (MEMS)
Advantages
– Open up scope for new services and new opportunities
– Improve energy efficiency as a single entity
– Potential thermal energy utilization
– Responsive to changes in market
– Power management at district (distribution) level
– Process optimization and improve reliability
– Could offer islanding operation and enhance power quality
Smart Meters for MEMS
● Features of smart meters– Time-of-the-day pricing
– Daily reading of consumption periods
– Daily retail settlement
●●●● What it can offer for MEMS– Collect information and help to
make collective decision
– Optimize the use of installed DERs, elastic loads, storages,
Singapore EMA and PA are working out smart meters (based
on wireless technology) which could be exploited for MEMS
– Daily retail settlement
– Daily wholesale settlement
– Innovative pricing and service packaging
– Consumers can plan their consumption
• Interruptible and elastic loads
– Consumers can choose to buy/sell electricity when they have storage or own generation
DERs, elastic loads, storages, heating and cooling
– Allow consumers to plan their consumption or MEMS to take control
– MEMS can take decision to generate own electricity when the market prices are high with its storages or own generation
A*STAR Intelligent Energy Distribution System (IEDS) Projects at NTU
● Power Converter & Grid Architectural Design for Future Intelligent Energy Distribution Networks (S$0.96 million),
PI: Andrew Loh.
● Microgrid Energy Management System (S0.96 million),
PI: Gooi HB.
● Open Architecture for Intelligent Power Quality Monitoring & ● Open Architecture for Intelligent Power Quality Monitoring & Evaluation System (S$0.6 million), PI: Choi SS.
● Design of a Voltage Collapse Monitoring Instrument using Local Information (S$0.48 million), PI: Haque MH.
● Intelligent Trading/Metering/Billing System for Future Smart Distribution System (S$0.48 million), PI: Wang P.
Total Grant is S$3.48 million.
MEMS OBJECTIVES
� To design software algorithms and control schemes for minimizing schedule cost or maximizing revenue of MEMS while ensuring its secure operation.
⇒⇒⇒⇒ Economic aspect: Predict total customer loads and perform
economic scheduling of distributed energy resources
(DERs).
⇒⇒⇒⇒ Security aspect: Monitor & control MEMS.⇒⇒⇒⇒ Security aspect: Monitor & control MEMS.
� To design hardware controllers and demonstrate how proposed prototype can coordinate and schedule one or more DERs and price-sensitive loads.
� To develop a web-based GUI and incorporate sensing and communication devices for interfacing with local DERs and loads, distribution networks and market operators.
MEMS SCOPE
� Support interconnected or islanding operation mode.
� Design load forecasting algorithms, e.g. ANN, for predicting total load.
� Engage Unit Commitment (UC) in economic scheduling of DERs.
� Optimal Power Flow (OPF) recommends maximum customer loads to connect and tap positions of on-line tap changers.loads to connect and tap positions of on-line tap changers.
� Implement recommended tap positions, MW shedding, Var switching and interruptible loads via active management.
� Perform on-line probabilistic security assessment based on normal operation or sudden disconnection from MV network.
� Design DC-DC and DC-AC converters for DERs.
� Implement web-based communication and control for various components of MEMS.
Integrated MicrogridIntegrated Microgrid
DC
ACDSO
IES
IES
SM
IES
1 MVA
22/0.4 kV
Transformer
HDB Housing Load
ConverterMV: Medium Voltage
LV: Low Voltage
MV
LV
Circuit Breaker
X
5 kWp
PV
AC Grid 3 phase 400V
Converter
5 kW
Wind Turbine
DSO: Distribution System Operator
MEMS: Microgrid Energy Management System
IES: Intelligent Energy Sensor
SM: Smart Meter
X
X X
X DCAC
AC
IES
IES
DC
AC
`
SM
SM
DC
AC
IES
Commercial
Load
Industrial
Load
Energy
Storage
(Battery, Super-
Capacitor or
Flywheel)
IESX X
X
MEMS
AC Grid: 3-phase 400V
IES
5 kW
Fuel Cell
Converter
X
X
X
XX
XConverter
© School of EEE, NTU, 2008
Microgrid on Microgrid on PPower ower MManagement anagement SSoftwareoftware
MonitoringProgramming
Measurements
State
Short Term Load
Forecasting
Unit Commitment
Actual Devices
PMS
State
EstimatorOptimal Power Flow
System Security
MIC
MCCB
ELR
MIC
MIC
MIC
MCCB
ELR
MIC
MIC
MIC
MCCB
ELR
MIC
MIC
MIC
MCCB
ELR
MIC
MIC
MIC
MCCB
ELR
MIC
MIC
MIC
MCCB
ELR
MIC
MIC
MIC
MCCB
ELR
MIC
MIC
MIC
MCCB
ELR
MIC
MIC
MIC
MCCB
ELR
MIC
MIC
Tap-out
Box at
ab
Bench
Tap-out
Box on
Wall
Tap-out
Box at
Lab
Bench
Tap-out
Box on
Wall
Tap-out
Box at
Lab
Bench
Tap-out
Box on
Wall
Tap-out
Box at
Lab
Bench
Tap-out
Box on
Wall
Tap-out
Box at
Lab
Bench
Tap-out
Box on
Wall
Tap-out
Box at
Lab
Bench
Tap-out
Box on
Wall
Tap-out
Box at
Lab
Bench
Tap-out
Box on
Wall
Tap-out
Box at
Lab
Bench
Tap-out
Box on
Wall
Tap-out
Box at
Lab
Bench
Tap-out
Box on
Wall
Level B8Impedance
BankImpedance
Bank
Impedance
Bank
Impedance
BankImpedance
Bank
Impedance
BankLoadLoadLoad
MIC
MCCB
ELR MIC
MCCB
ELR MIC
MCCB
ELR MIC
MCCB
ELR MIC
MCCB
ELR MIC
MCCB
ELR MIC
MCCB
ELR MIC
MCCB
ELR MIC
MCCB
ELR
Level B7
Microgrid Network Control Centre
MIC
×××× ST
ELR
×××× ×××× ××××
Bench 2
Junction box
MIC ×××× ×××× ××××
××××32A
Motorized
MCCB ST
ELR
×××× ×××× ××××
Bench 1
Junction box
32A
Motorized
MCCB
×××× ×××× ××××MIC
2A
2A
MIC
2A
2A
×××× ×××× ××××
100 A Selector
Switch
100A selector
switch
25mm2 (90A)
×××× ×××× ××××
18 kVAPowerSource
Details of Network Control Panel
A Sustainable and Efficient Electrical & Thermal Energy System
- Thermal energy is captured through solar thermal energy
collectors coupled with waste heat recovered from DGs.
- Solid state magnetocaloric nanomaterials which possess
special magnetic and thermal characteristics can be used in
enhancing the efficiency of cooling systems.
- An integrated solution which manages cooling/heating, hot
water and power in a micro grid via low cost communication water and power in a micro grid via low cost communication
networks.
- Design and develop an EV energy management system.
- Implement metering and billing by landlord and energy sale
and purchase by tenants.
Gooi HB, Vilathgamuwa DM, Low KS of EEE, Wong TN, Duan F of MAE and Ramanujan
RV of MSE
Proposed by:
A Sustainable and Efficient Electrical & Thermal Energy System - Contd
Solar Thermal
Energy Collector
Renewable Energy
Sources and Energy
Storage
Micro Grid Energy Magnetocaloric
Interruptible
Loads
A*STAR MEMS
Micro-turbines
Micro Grid Energy
Management
System
Upstream
Networks
Magnetocaloric
Thermal Manage-
ment System
EV Energy
Conversion
Energy flow
Control and/or
Communication
Other Related Power Projects
● National Research Foundation (NRF) Project, ‘Zero Energy’ Green Water Production and Recycling System Using Membrane Distillation (MD) and Membrane Distillation Bioreactor (MDBR) powered by solar energy (S$10 million), PI: Choo FH(S$10 million), PI: Choo FH
● Atlantis Resources Corporation & NTU Joint Project - An Efficient System for Underwater Power Generation (S$0.6 million), PI: Tseng KJ.
Q & A Session
Low Voltage PanelLow Voltage Panel
LV System
Max. Power: 30 kVA
Rated Voltage: 400 V, 3 Phase SystemLV Brain Cards
Solar battery charging and grid interfacing inverter system
1. Day time battery is charged from excess energy in solar panel
2. In the night time battery is discharged to supply the load demand
3. Local controlling using dspace DS1103
4. Power management and high level controlling using ION Power Management Software
Demonstration systems solar battery charger and grid interface • Solar 160-230 V 1.1 kW
• Battery bank 100 V, 128 Ah
• Simulated grid 220 V rms L-L
• 3-kW variable load bank
Power converter
Battery bank
Fuel Cell System
• Acquiring of hydrogen supply to power the 5-KW fuel cell system
• Design high boost converter topologies for interface
Four new families of ZSI are proposed with extended boosting capability particularly for Fuel cell systems
– Diode assisted
– Capacitor assisted
– Continuous current
– Discontinuous current
5-kW Fuel Cell Proposed Hydrogen Storage at S2-B7
– Discontinuous current
Diode assisted continuous current qZSI
( )( ) DC
SS
SV
DDv
−−=
121
1ˆ
2
ˆˆ S
x
vMv =
Capacitor assisted discontinuous current qZSI
( ) DC
S
SV
Dv
31
1ˆ
−=
Wind EnergyWind Energy
Wind Turbine
Rated Power: 2.4 kW
Wind Energy Simulator
Rated Power: 7.5 kW