www.smart-microgrid.ca project 1.4 operational strategies and storage technologies to address...

www.smart-microgrid.ca

Project 1.4Operational Strategies and Storage Technologies to Address Barriers for Very High Penetration of DG Units in Intelligent Microgrids Dr. Géza JoósStudent: Michael Ross


Purpose and Challenges• Create a general framework for energy

management of Microgrids with large amounts of renewables– Controlling a Microgrid with a high level of

uncertainty and variability (e.g., stochastic nature of renewable generation).

• The methodology will be implemented for different renewable energy portfolios and power system configurations– Developing an operation strategy that

maximizes economic considerations– Incorporating various DER


2011

•Identify barriers associated for large number of renewable DGs & research energy management strategies

2012

•Establish performance metrics considering cost optimization

2013

•Evaluate Storage technologies, modes of operation, ancillary service functions and values

2014

•Research and develop controlling strategies and algorithms

2015

•Evaluate performance of strategies


Enhancement for Canada’s future power system

Industrial experience

Cutting edge research


Project 1.4 Operational Strategies &

Storage Technologies for a large penetration of

renewable DGs

Projects 1.1 & 1.2Control, operation

and power management

Projects 2.2 & 2.4Energy & supply

security and Integration design

Projects 3.1 & 3.2Communication

infrastructure and Grid integration


Barriers for Large Number of Renewable DGs• Bi-Directional Power Flow• Protection Coordination• System Grounding Issues• Unintentional Islanding• Power Balancing• Ancillary Services


Bi-directional power flow• There may be times of high input

power and low consumption, and other times of high demand but low generation.– This is a problem since the voltage

regulation is difficult to control (voltage rise effect).

• Power can be exported as well as imported

• A fault on a lateral feeder can be “seen” on a healthy feeder, causing it to trip

Source: NRCan


Protection Coordination• Loss of coordination (fault currents can

be larger, which means that some protective equipment can trip simultaneously)

• Loss of sensitivity (if the fault is located downstream of the DG, the utility might not be able to detect that a fault occurred).

• Nuisance fuse blowing


Protection Coordination• Fault currents can vary widely based

on whether microgrids are connected to the grid, or disconnected– Protection equipment must know when

the microgrid is isolated or grid-connected


System Grounding Issues• Grounding issues of the DG and

interconnecting transformer can cause either overvoltages in a line-single to-ground fault, or it can increase the short circuit current by allowing a path for zero-sequence currents to flow


Unintentional Islanding• The DG can reconnect out of phase

with the utility• The DG can be damaged in a fault

condition• There is a risk to personnel who may

operate on an energized feeder• DGs may not have voltage or

frequency support


Power Balancing• Load following controls must be in

place when the DG is large enough such that many loads on the feeder are supplied with power from the DG, or when operating as a microgrid.

• This is particularly difficult with renewable DGs since the input power is intermittent.


Ancillary Services• The feeder cannot rely on generator

inertia (if interfaced through power-electronics) with dynamic changes in load– Must rely on other sources (energy

storage, for example) to ensure inertial frequency response for the initial energy balance when a new load comes online/offline


Current Interconnection Standards• IEEE 1547• Requirements for the Interconnection

of Distributed Generation to the Hydro-Quebec Medium-Voltage Distribution System

• BC Hydro Interconnection Requirements for Power Generators

• Hydro One Distributed Generation Technical Interconnection Requirements


Energy Management Strategies• Load curtailment – Demand response– Direct load control

• Generation curtailment – Including dump loads

• Energy Storage Systems– Batteries– Flywheels– Supercapacitors– Etc.


Gaps:- Other barriers for high

penetration renewable DGs?- Other interconnection

standards?- Energy management strategies?


Project 1.4 Operational Strategies and Storage Technologies to Address Barriers for Very High Penetration of DG Units in

Intelligent Microgrids

For further information contact:Michael Ross

[email protected]

www.smart-microgrid.ca project 1.4 operational strategies and storage technologies to address...

Documents

nrcan slide

grid integration slide

gridconnected slide

edge research slide

power management projects

power system configurations

michael ross slide

fault condition