MICROGRID ENERGY MANAGEMENT SYSTEM AND POWER STORAGE METHOD FOR ENERGY STORAGE SYSTEM

• US 20160190822A1
• Filed: 12/30/2014
• Published: 06/30/2016
• Est. Priority Date: 12/30/2014
• Status: Abandoned Application

• Current Assignee: LG CNS Company Limited (LG Corporation)
• Original Assignee: LG CNS Company Limited (LG Corporation)
• Inventors: PARK, Gun Dong, LEE, Hyunah, LEE, Jeong Hwan
• Application Number:
  US14/586,429
• Publication Number:
  US 20160190822A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H02J 3/003 Load forecast, e.g. methods or systems for forecasting future load demand
• CPC Class Codes: H02J 3/32 using batteries with converting means
• CPC Class Codes: H02J 9/06 with automatic change-over , e.g. UPS systems
• CPC Class Codes: Y04S 10/50 Systems or methods supporting the power network operation or management, involving a certain degree of interaction with the load-side end user applications

Abstract

A power storage method for an energy storage system (ESS) is provided. The method includes determining a total quantity of power currently available in a power supply and a quantity of power currently required by a plurality of loads, determining a quantity of residual power currently available based on the total quantity of power currently available and the quantity of power currently required, and charging an ESS of a load determined as having a highest priority with the total power currently available while charging other ESSs of other loads with the residual power currently available.

Claims

1. A power distribution method for an energy management system (EMS), the method comprising:

determining a total quantity of power currently available in a power supply;

determining a quantity of power currently required by a plurality of loads each associated an energy storage system (ESS) of a plurality of energy storage systems ESSs;

determining a quantity of residual power currently available based on the total quantity of power currently available and the quantity of power currently required; and

charging the ESS associated with one of the plurality of loads determined as having a highest priority with the total power currently available while charging other ESSs associated with the other of the plurality of loads with the residual power currently available.

2. The method of claim 1, wherein charging the other ESSs comprises:

determining an ESS associated with the other of the plurality of loads that has a state of charge (SoC) less than a minimum allowable SoC; and

charging the determined ESS first with the residual power currently available.

3. The method of claim 1, further comprising:

determining a priority for each of the plurality of loads; and

sequentially charging the ESS associated with each of the plurality of loads according to the determined priority.

4. The method of claim 3, wherein sequentially charging the ESS comprises:

charging a first ESS associated with a load of the plurality of loads determined as having a highest priority; and

charging the ESSs associated with the other loads of the plurality of loads determined as having lower priorities after a state of charge (SoC) of the first ESS reaches a predetermined minimum value.

5. The method of claim 3, wherein sequentially charging the ESS comprises:

charging an ESS associated with a load of the plurality of loads determined as having a highest priority with a higher percentage of the residual power currently available by allocating the residual power according to a fixed ratio.

6. The method of claim 5, wherein:

the plurality of loads consist of a high-priority load, a general load and a low-priority load; and

the fixed ratio allocates 50% of the residual power currently available to the high priority load, allocates 30% of the residual power currently available to the general load and allocates 20% of the residual power currently available to the low-priority load.

7. The method of claim 3, wherein sequentially charging the ESS comprises:

charging the ESS associated with a load of the plurality of loads determined as having a highest priority such that the ESS has a higher state of charge (SoC) than ESSs associated with the other of the plurality of loads.

8. The method of claim 1, wherein determining the quantity of residual power currently available comprises:

determining that the total quantity of power currently available exceeds the quantity of power currently required by at least a threshold value.

9. The method of claim 1, further comprising:

switching the plurality of ESSs to a discharge mode or maintaining the plurality of ESSs at a current charge level when it is determined that no quantity of residual power is currently available.

10. The method of claim 9, wherein the discharge mode comprises:

determining that a charge level of the ESS associated with one of the plurality of loads determined as having the highest priority is insufficient; and

allocating power of at least one ESS associated with another of the plurality of loads determined as having a lower priority to charge the ESS associated with the one of the plurality of loads determined as having the highest priority.

11. A microgrid energy measurement system comprising:

a power determination apparatus configured to determine a total quantity of power currently available in a power supply;

a power consumption determination apparatus configured to determine a quantity of power currently required by a plurality of loads each associated an energy storage system (ESS) of a plurality of energy storage systems ESSs;

a residual power determination apparatus configured to determine a quantity of residual power currently available based on the total quantity of power currently available and the quantity of power currently required; and

a control apparatus configured to charge the ESS associated with one of the plurality of loads determined as having a highest priority with the total power currently available while charging other ESSs associated with the other of the plurality of loads with the residual power currently available.

12. The energy management system of claim 11, further comprising:

a state of charge (SoC) apparatus configured to determine an ESS associated with the other of the plurality of loads that has an SoC less than a minimum allowable SoC,

wherein the control apparatus is further configured to charge the determined ESS first with the residual power currently available.

13. The energy management system of claim 11, wherein the control apparatus is further configured to:

determine a priority for each of the plurality of loads; and

sequentially charge the ESS associated with each of the plurality of loads according to the determined priority.

14. The energy management system of claim 13, wherein sequentially charging the ESS comprises:

charging a first ESS associated with a load of the plurality of loads determined as having a highest priority; and

charging the ESSs associated with the other loads of the plurality of loads determined as having lower priorities after a state of charge (SoC) of the first ESS reaches a predetermined minimum value.

15. The energy management system of claim 13, wherein sequentially charging the ESS comprises:

charging the ESS associated with a load of the plurality of loads determined as a highest priority with a higher percentage of the residual power currently available by dividing the residual power according to a fixed ratio.

16. The energy management system of claim 15, wherein:

the plurality of loads consist of a high-priority load, a general load and a low-priority load; and

the fixed ratio allocates 50% of the residual power currently available to the high priority load, allocates 30% of the residual power currently available to the general load and allocates 20% of the residual power currently available to the low-priority load.

17. The energy management system of claim 13, wherein sequentially charging the ESS comprises:

charging the ESS associated with a load of the plurality of loads determined as having a highest priority such that the ESS has a higher state of charge (SoC) than ESSs associated with the other of the plurality of loads.

18. The energy management system of claim 11, wherein determining the quantity of residual power currently available comprises:

determining that the total quantity of power currently available exceeds the quantity of power currently required by at least a threshold value.

19. The energy management system of claim 11, wherein the control apparatus is further configured to switch the plurality of ESSs to a discharge mode or maintain the plurality of ESSs at a current charge level when it is determined that no quantity of residual power is currently available.

20. The energy management system of claim 19, wherein the discharge mode comprises:

determining that a charge level a of the ESS associated with one of plurality of loads determined as having the highest priority is insufficient; and

allocating power of at least one ESS associated with another of the plurality of loads determined as having a lower priority to charge the ESS associated with the one of the plurality of loads determined as having the highest priority.