03-07-2014, 12:09 PM
SIZING OF ENERGY STORAGE FOR MICROGRID
[attachment=65581]
Introduction To Microgrid
What is Microgrid?
Small-Scale Power Supply Network to provide Power for a Small Community.
Local Power Generation for local loads.
Small Power Generating sources
Highly Flexible
Efficient.
The Need Of Microgrid
Microgrid could be the answer to our energy crisis.
Transmission losses gets highly reduced.
Microgrid results in substantial savings and cuts emissions without major changes to lifestyles.
Provide high quality and reliable energy supply to critical loads
Microgrid components
wind turbine
Microturbine
Photovoltaic system
Controller
Fuel cell
Energy storage system
Energy storage system
ESS include electrochemical battery, super capacitor, compressed air energy storage, super conducting energy storage, flywheel energy storage etc. .
Lithium ion is commonly used because best energy to weight ratio and slow loss of charge when not in use.
ESS store energy at the time of surplus and redispatch it when needed.
Microgrid Operating Modes
Island Mode:
Utility grid is not supplying power
Static switch is open.
Feeder A, B, C are being supplied
by Microsources.
Feeder D (not sensitive )
is dead.
ESS in islanded microgrid
Sizing of a suitable battery bank in terms of power and energy help in shaving the peak demand.
Stores excess renewable energy and supply load when renewable energy is low.
When ESS discharges its energy to power grid its generating positive real power
ESS in grid connected microgrid
The upstream grid can be treated as bidirectional generator which generate positive power when power is transferred from the MG and generate negative power when the power transferred from the MG to upstream grid.
The output of bidirectional generator is limited by the capacity of transmission line between the MG and upstream grid
Algorithm steps
1.Enter forecasting renewable power and load. Calculate minimum BESS capacity CEmin.
2.Set CEmax , ∆ CE and initialize the variables.
3.Solve the objective function for CE. Minimize the TC for islanded MG and maximize TB for grid connected MG.
4.If CE < CE max, update CE using the above equation . The algorithm will stop when
CE ≥ CEmax.
Conclusion
BESS for MG decrease the schedule cost of MG in islanded MG and increase benefit of MG.
As the size of BESS increases, the benefit increases.
The TCPD increases in a constant rate and when the size of BESS is greater than optimal size TC will increase in islanded MG and TB will reduce in grid connected MG
[attachment=65581]
Introduction To Microgrid
What is Microgrid?
Small-Scale Power Supply Network to provide Power for a Small Community.
Local Power Generation for local loads.
Small Power Generating sources
Highly Flexible
Efficient.
The Need Of Microgrid
Microgrid could be the answer to our energy crisis.
Transmission losses gets highly reduced.
Microgrid results in substantial savings and cuts emissions without major changes to lifestyles.
Provide high quality and reliable energy supply to critical loads
Microgrid components
wind turbine
Microturbine
Photovoltaic system
Controller
Fuel cell
Energy storage system
Energy storage system
ESS include electrochemical battery, super capacitor, compressed air energy storage, super conducting energy storage, flywheel energy storage etc. .
Lithium ion is commonly used because best energy to weight ratio and slow loss of charge when not in use.
ESS store energy at the time of surplus and redispatch it when needed.
Microgrid Operating Modes
Island Mode:
Utility grid is not supplying power
Static switch is open.
Feeder A, B, C are being supplied
by Microsources.
Feeder D (not sensitive )
is dead.
ESS in islanded microgrid
Sizing of a suitable battery bank in terms of power and energy help in shaving the peak demand.
Stores excess renewable energy and supply load when renewable energy is low.
When ESS discharges its energy to power grid its generating positive real power
ESS in grid connected microgrid
The upstream grid can be treated as bidirectional generator which generate positive power when power is transferred from the MG and generate negative power when the power transferred from the MG to upstream grid.
The output of bidirectional generator is limited by the capacity of transmission line between the MG and upstream grid
Algorithm steps
1.Enter forecasting renewable power and load. Calculate minimum BESS capacity CEmin.
2.Set CEmax , ∆ CE and initialize the variables.
3.Solve the objective function for CE. Minimize the TC for islanded MG and maximize TB for grid connected MG.
4.If CE < CE max, update CE using the above equation . The algorithm will stop when
CE ≥ CEmax.
Conclusion
BESS for MG decrease the schedule cost of MG in islanded MG and increase benefit of MG.
As the size of BESS increases, the benefit increases.
The TCPD increases in a constant rate and when the size of BESS is greater than optimal size TC will increase in islanded MG and TB will reduce in grid connected MG