Method and system for mitigating impact of malfunction in actual load determination on peak load management

• US 8,761,949 B2
• Filed: 05/31/2012
• Issued: 06/24/2014
• Est. Priority Date: 05/31/2012
• Status: Expired due to Fees

• Current Assignee: NantEnergy, Inc.
• Original Assignee: Sharp Laboratories of America Incorporated (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Mansfield, Carl
• Primary Examiner(s): Jarrett, Ryan
• Assistant Examiner(s): SCAPIN, MICHAEL JOSEPH
• Application Number:
  US13/484,633
• Publication Number:
  US 20130325198A1
• Time in Patent Office: 754 Days
• Field of Search: 700/291
• US Class Current: 700/291
• CPC Class Codes: H02J 2300/24 of photovoltaic origin
• CPC Class Codes: H02J 2310/12 The local stationary network supplying a household or a building
• CPC Class Codes: H02J 3/32 using batteries with converting means
• CPC Class Codes: H02J 3/381 Dispersed generators
• CPC Class Codes: Y02E 10/56 Power conversion systems, e.g. maximum power point trackers
• CPC Class Codes: Y02E 70/30 Systems combining energy storage with energy generation of non-fossil origin
• CPC Class Codes: Y02P 80/14 District level solutions, i.e. local energy networks

Abstract

Method and system for mitigating the impact on peak load management of a malfunction in determining actual load at a site by substituting a predicted load for actual load while the malfunction persists. Using a predicted load as a substitute for actual load during the malfunction period avoids use of a grossly overestimated or underestimated actual load that if used could cause suboptimal use of battery power and decimate cost savings from peak load management.

Claims

1. A peak load management system, comprising:

a battery system configured to store power and discharge stored power;

a measurement system configured to measure actual load; and

a peak load management controller operatively coupled with the battery system and the measurement system and configured to receive actual load data from the measurement system, detect malfunctions in determining actual load, compare an effective load and a target peak load and regulate a discharge of stored power from the battery system based at least in part on outcomes of comparisons of the effective load and the target peak load, wherein the management controller is further configured to use actual load as the effective load in first comparisons of the effective load and the target peak load and, in response to detecting a malfunction in determining actual load, substitute a predicted load for actual load as the effective load in second comparisons of the effective load and the target peak load, wherein the management controller is further configured to detect recoveries from malfunctions in determining actual load and, in response to detecting a recovery from the malfunction, substitute actual load for the predicted load as the effective load in third comparisons of the effective load and the target peak load.

2. The management system of claim 1, wherein the management controller is further configured to compute the predicted load based at least in part on past actual load.

3. The management system of claim 1, wherein the discharge of stored power from the battery system is regulated at least in part by discharging stored power from the battery system when actual load exceeds the target peak load.

4. The management system of claim 1, wherein the discharge of stored power from the battery system is regulated at least in part by discharging stored power from the battery when the predicted load exceeds the target peak load.

5. The management system of claim 1, wherein the malfunction comprises a malfunction of the measurement system.

6. The management system of claim 1, wherein the malfunction comprises a malfunction of a communication channel between the measurement system and the management controller.

7. The management system of claim 1, wherein the malfunction comprises a malfunction of the management controller.

8. The management system of claim 1, wherein the management controller is further configured to shed actual load in response to the malfunction.

9. The management system of claim 8, wherein the management controller is configured to use weather data to determine an amount of actual load that is shed.

10. The management system of claim 1, wherein actual load is a net load representing power consumed at a site reduced by power generated at the site.

11. A peak load management method, comprising the steps of:

measuring, by a peak load management system, actual load;

detecting, by the management system, a malfunction in determining actual load;

detecting, by the management system, a recovery from the malfunction in determining actual load;

comparing, by the management system, an effective load and a target peak load; and

regulating, by the management system, a discharge of stored battery power based at least in part on outcomes of comparisons of the effective load and the target peak load,

wherein the management system uses actual load as the effective load in first comparisons of the effective load and the target peak load and, in response to detecting the malfunction in determining actual load, substitutes a predicted load for actual load as the effective load in second comparisons of the effective load and the target peak load and, in response to detecting the recovery from the malfunction in determining actual load, substitutes actual load for the predicted load as the effective load in third comparisons of the effective load and the target peak load.

12. The management method of claim 11, further comprising the step of:

detecting, by the management system, recoveries from malfunctions in determining actual load,

wherein the management system detects a recovery from the malfunction and, in response to detecting the recovery, substitutes actual load for the predicted load as the effective load in third comparisons of the effective load and the target peak load.

13. The management method of claim 11, further comprising the step of computing, by the management system, the predicted load based at least in part on past actual load.

14. The management method of claim 11, wherein the predicted load is an expected load on a worst case day of a billing period.

15. The management method of claim 11, wherein the discharge of stored power from the battery system is regulated at least in part by discharging stored power from the battery system when actual load exceeds the target peak load.

16. The management method of claim 11, wherein the discharge of stored power from the battery system is regulated at least in part by discharging stored power from the battery when the predicted load exceeds the target peak load.

17. The management method of claim 11, wherein the malfunction comprises a malfunction of a measurement system.

18. The management method of claim 11, wherein the malfunction comprises a malfunction of a communication channel between a measurement system and a management controller.

19. The management method of claim 11, wherein the malfunction comprises a malfunction of a management controller.

20. The management method of claim 11, further comprising the step of shedding, by the management system, actual load in response to the malfunction.

21. The management method of claim 20, wherein an amount of actual load that is shed is determined by the management system using weather data.

22. The management method of claim 11, wherein actual load is a net load representing power consumed at a site reduced by power generated at the site.