Systems and methods for controlling operations of a heating and cooling system

Patent metadata

Field	Value
Publication number	US-10247436-B2
Application number	US-201615258905-A
Country	US
Kind code	B2
Filing date	Sep 7, 2016
Priority date	Sep 7, 2016
Publication date	Apr 2, 2019
Grant date	Apr 2, 2019

Abstract

Techniques for controlling a heating, ventilation and air conditioning (HVAC) system at a site are disclosed. A disclosed method includes obtaining or calculating a net load at the site and obtaining a temperature of the site during a time period. The method further includes comparing the net load to a threshold load value and comparing the temperature to a lower threshold temperature or an upper threshold temperature. The method also includes determining one or more operation parameter values for the HVAC system based at least in part on the comparison of the net load to the threshold load value and the comparison of the temperature to the lower threshold temperature or the upper threshold temperature, and setting the HVAC system based on the one or more operation parameter values.

First claim

What is claimed is:

1. A method of controlling a heating, ventilation and air conditioning (HVAC) system at a site having an energy generation (EG) system, the method comprising:
obtaining one or more operation parameter values for the HVAC system;
obtaining a net load at the site during a time period, the net load indicating a difference between a gross electric load at the site and an output of the EG system at the site, wherein the EG system includes a photovoltaic system;
obtaining a temperature of the site during the time period;
comparing, with a processor, the net load to a threshold load value;
comparing, with the processor, the temperature to at least one of a lower threshold temperature or an upper threshold temperature of the one or more operation parameter values;
determining one or more new operation parameter values for the HVAC system based, at least in part, on the comparison of the net load to the threshold load value and the comparison of the temperature to the lower threshold temperature or the upper threshold temperature; and
controlling the HVAC system based on the determined one or more new operation parameter values.

2. The method of claim 1 , wherein determining the one or more new operation parameter values for the HVAC system includes:
when the net load is below the threshold load value, determining the one or more new operation parameter values for the HVAC system to increase a power consumption of the HVAC system; or
when the net load is at or above the threshold load value, determining the one or more new operation parameter values for the HVAC system based on at least one of a predicted future net load or information regarding a current energy price and a future energy price.

3. The method of claim 2 , wherein increasing the power consumption of the HVAC system includes at least one of:
setting the HVAC system to a high power mode;
setting the HVAC system to a low power mode;
decreasing a temperature set point of the HVAC system; or
increasing a speed of a fan of the HVAC system.

4. The method of claim 2 , wherein increasing the power consumption of the HVAC system includes:
determining whether a high power mode of the HVAC system can be supported while keeping the net load below the threshold load value; and
performing one of
setting the HVAC system to the high power mode when the high power mode of the HVAC system can be supported while keeping the net load below the threshold load value; and
setting the HVAC system to a low power mode when the high power mode of the HVAC system cannot be supported while keeping the net load below the threshold load value.

5. The method of claim 2 , further comprising:
predicting a future gross electric load and a future output of the EG system based on at least one of historical data or weather forecast; and
determining the predicted future net load based on the predicted future gross electric load and the predicted future output of the EG system.

6. The method of claim 2 , wherein determining the one or more new operation parameter values for the HVAC system based on at least one of the predicted future net load or the information regarding the current energy price and the future energy price includes:
determining the one or more new operation parameter values for the HVAC system to decrease the power consumption of the HVAC system when the predicted future net load is below the threshold load value, or when the future energy price is lower than the current energy price.

7. The method of claim 6 , wherein decreasing the power consumption of the HVAC system includes at least one of:
setting the HVAC to a low power mode;
increasing a temperature set point of the HVAC system;
decreasing a speed of a fan of the HVAC system; or
turning off a compressor of the HVAC system and increasing the speed of the fan of the HVAC system.

8. The method of claim 1 , wherein determining the one or more new operation parameter values for the HVAC system includes one of:
when the temperature is below the lower threshold temperature, determining the one or more new operation parameter values for the HVAC system to turn off the HVAC system;
when the temperature is above the upper threshold temperature, determining the one or more new operation parameter values for the HVAC system to increase a power consumption of the HVAC system; and
when the temperature is between the lower threshold temperature and the upper threshold temperature, determining the one or more new operation parameter values for the HVAC system based on the net load of the site.

9. The method of claim 8 , wherein increasing the power consumption of the HVAC system includes at least one of:
setting the HVAC system to a high power mode;
setting the HVAC system to a low power mode;
decreasing a temperature set point of the HVAC system; or
increasing a speed of a fan of the HVAC system.

10. The method of claim 8 , wherein determining the one or more new operation parameter values for the HVAC system based on the net load of the site includes:
when the net load is below the threshold load value, selecting the one or more new operation parameter values for the HVAC system to decrease the temperature; or
when the net load is at or above the threshold load value, determining the one or more new operation parameter values for the HVAC system based on at least one of a predicted future net load or information regarding a current energy price and a future energy price.

11. The method of claim 10 , wherein determining the one or more new operation parameter values for the HVAC system based on at least one of the predicted future net load or the information regarding the current energy price and the future energy price includes:
determining the one or more new operation parameter values for the HVAC system to decrease the power consumption of the HVAC system when the predicted future net load is below the threshold load value, or when the future energy price is lower than the current energy price.

12. The method of claim 11 , wherein decreasing the power consumption of the HVAC system includes at least one of:
setting the HVAC to a low power mode;
increasing a temperature set point of the HVAC system;
decreasing a speed of a fan of the HVAC system; or
turning off a compressor of the HVAC system and increasing the speed of the fan of the HVAC system.

13. The method of claim 1 , wherein the one or more new operation parameter values include at least one of:
a temperature set point;
a fan speed;
a temperature cycle time; or
a high power mode or a low power mode.

14. The method of claim 1 , wherein determining the one or more new operation parameter values for the HVAC system is further based on an upper limit of energy cost of the site in a billing cycle.

15. The method of claim 1 , wherein the one or more new operation parameter values for the HVAC system include operation parameters for an air conditioner of the HVAC system or operation parameters for a heater of the HVAC system.

16. The method of claim 1 , wherein obtaining the net load at the site includes at least one of:
obtaining the net load from a meter; or
calculating the net load based on a measured gross electric load and a measured actual output of the EG system at the site.

17. A control system for controlling a heating, ventilation and air conditioning (HVAC) system at a site having an energy generation (EG) system, the control system comprising:
a processor;
a memory communicatively coupled to the processor, the memory including instructions

Assignees

• Solarcity Corp

Inventors

• Carlson Eric Daniel
• Zimmerly Brian L

Classifications

• F24F2140/50

  Load · CPC title

• G05B13/026

  using a predictor · CPC title

• F24F11/30 Primary

  for purposes related to the operation of the system, e.g. for safety or monitoring · CPC title

• F24F2140/60

  Energy consumption · CPC title

• F24F2130/00

  Control inputs relating to environmental factors not covered by group F24F2110/00 · CPC title