Cascaded systems and methods for controlling energy use during a demand limiting period

Patent metadata

Field	Value
Publication number	US-11099526-B2
Application number	US-201916284895-A
Country	US
Kind code	B2
Filing date	Feb 25, 2019
Priority date	Sep 30, 2011
Publication date	Aug 24, 2021
Grant date	Aug 24, 2021

Abstract

A cascaded control system is configured to control power consumption of a building during a demand limiting period. The cascaded control system includes an energy use setpoint generator and a feedback controller. The energy use setpoint generator is configured to use energy pricing data and measurements of a variable condition within the building to generate an energy use setpoint during the demand limiting period. The feedback controller is configured to use a difference between the energy use setpoint and a measured energy use to generate a control signal for building equipment that operate to affect the variable condition within the building during the demand limiting period.

First claim

What is claimed is:

1. A system comprising:
a processing circuit configured to:
generate an energy use setpoint based on energy price data and subject to a constraint defining a comfort threshold, wherein the processing circuit is configured to estimate a value for the energy use setpoint that will result in a variable condition within a building reaching the comfort threshold; and
generate a control signal for equipment based on a difference between the energy use setpoint and a measured energy use.

2. The system of claim 1 , wherein the equipment is configured to serve a plurality of buildings.

3. The system of claim 1 , wherein the processing circuit is configured to use a demand limiting technique to generate the energy use setpoint subject to the constraint.

4. The system of claim 1 , wherein the comfort threshold comprises a maximum temperature.

5. The system of claim 1 , wherein the processing circuit is configured to use a history of values for the energy use setpoint from a previous demand limiting period and a history of measurements of the variable condition from the previous demand limiting period to estimate the value of the variable condition at an end of a current demand limiting period.

6. The system of claim 1 , wherein the processing circuit is configured to:
determine a probability that the energy use setpoint is successful in maintaining the variable condition within an acceptable range of values; and
generate the energy use setpoint subject to a constraint defining a probability threshold such that the determined probability is greater than or equal to the probability threshold.

7. The system of claim 1 , wherein the processing circuit is configured to calculate an expected cost resulting from the energy use setpoint.

8. The system of claim 1 , wherein the processing circuit is configured to calculate the energy use setpoint by optimizing an objective function.

9. The system of claim 1 , wherein the processing circuit is located remotely relative to the equipment.

10. The system of claim 1 , wherein the processing circuit is configured to cause the system to engage in a financial incentive program of a utility company.

11. A system comprising:
a processing circuit configured to:
generate an energy use setpoint subject to a constraint defining a comfort threshold such that the energy use setpoint is estimated to result in a variable condition reaching the comfort threshold at an end of a time period; and
generate a device setpoint based on a difference between the energy use setpoint and a measured energy use; and

a controller configured to operate a device to achieve the device setpoint.

12. The system of claim 11 , wherein the processing circuit is configured to use a demand limiting technique to generate the energy use setpoint subject to the constraint.

13. The system of claim 11 , wherein the processing circuit is configured to calculate an expected cost resulting from the energy use setpoint.

14. The system of claim 11 , wherein the processing circuit is configured to:
determine a demand limiting period; and
generate the energy use setpoint such that load is shifted away from the demand limiting period.

15. The system of claim 11 , wherein the device comprises an HVAC device and the time period is a demand limiting period.

16. The system of claim 11 , comprising a remote server located remotely from the device and comprising the processing circuit.

17. The system of claim 16 , wherein the remote server is configured to provide an automated measurement and validation protocol.

18. A method comprising:
generating an energy use setpoint estimated to result in a variable condition within a building reaching a comfort threshold at an end of a time period;
generating a control signal for equipment based on a difference between the energy use setpoint and a measured energy use; and
causing the equipment to operate in accordance with the control signal.

19. The method of claim 18 , wherein the equipment operates to affect the variable condition, wherein the variable condition is a zone temperature for the building.

20. The method of claim 18 , wherein generating the energy use setpoint comprises using a demand limiting technique.

21. The method of claim 18 , wherein the time period is a demand limiting period corresponding to a demand response event.

22. The method of claim 18 , further comprising calculating an expected cost resulting from the energy use setpoint.

23. The method of claim 18 , further comprising determining a demand response event that defines the time period;
wherein the energy use setpoint is generated such that load is shifted away from the time period.

24. The method of claim 18 , wherein the equipment comprises HVAC equipment, and wherein the method comprises receiving communications from one or more smart meters.

25. The method of claim 18 , wherein the energy use setpoint is estimated to result in the variable condition trending toward the comfort threshold during the time period.

26. The method of claim 18 , wherein the equipment comprises cooling equipment, the comfort threshold is a maximum allowed temperature threshold, and the energy use setpoint is estimated to allow a zone temperature to increase toward the maximum allowed temperature threshold during the time period.

27. The method of claim 18 , wherein generating the energy use setpoint is performed subject to a first constraint based on the comfort threshold and a second constraint based on a second comfort threshold.

Assignees

• Johnson Controls Tech Co

Inventors

• Wenzel Michael J
• Drees Kirk H

Classifications

• F24F2120/00

  Control inputs relating to users or occupants · CPC title

• F24F11/63

  Electronic processing · CPC title

• F24F11/58

  using Internet communication · CPC title

• F24F11/38

  Failure diagnosis · CPC title

• F24F11/47

  Responding to energy costs · CPC title