Dynamic ventilation control for a building

Patent metadata

Field	Value
Publication number	US-11846440-B2
Application number	US-202217570978-A
Country	US
Kind code	B2
Filing date	Jan 7, 2022
Priority date	Jan 14, 2021
Publication date	Dec 19, 2023
Grant date	Dec 19, 2023

Abstract

Appropriate ventilation for a building space while maintaining building comfort includes tracking one or more interior environmental conditions within the building space and one or more exterior environmental conditions outside of the building space during operation of the HVAC system. An environmental model for the building space is learned over time based at least in part on these tracked environmental conditions, where the environmental model predicts an environmental state of the building space in response to operation of the HVAC system under various interior and exterior environmental conditions. A maximum allowed ventilation rate that can be achieved without causing the HVAC system to compromise on any of one or more comfort conditions of the building space is predicted using the environmental model. The outdoor air ventilation damper of the HVAC system is then controlled to provide an appropriate ventilation up to or at the predicted maximum allowed ventilation rate.

First claim

What is claimed is:

1. A method for providing up to a maximum ventilation for a building space while not compromising on one or more comfort conditions in the building space using a Heating, Ventilating and/or Air Conditioning (HVAC) system that includes an outdoor air ventilation damper, the HVAC system including a heating and/or cooling capacity, the method comprising:
tracking one or more interior environmental conditions within the building space and one or more exterior environmental conditions outside of the building space during operation of the HVAC system;
learning an environmental model for the building space over time based at least in part on the tracked one or more interior environmental conditions within the building space and the one or more exterior environmental conditions outside of the building space during operation of the HVAC system, wherein the environmental model predicts an environmental state of the building space in response to operation of the HVAC system under various interior and exterior environmental conditions;
predicting a current maximum allowed ventilation rate of outside air having the one or more exterior environmental conditions that can be conditioned by the HVAC system without exceeding the heating and/or cooling capacity of the HVAC system and without causing the HVAC system to compromise on any of the one or more comfort conditions of the building space, wherein predicting the current maximum allowed ventilation rate comprises inputting to the environmental model of the building space one or more comfort parameters associated with the one or more comfort conditions of the building space, one or more current interior environmental conditions and one or more current exterior environmental conditions; and
controlling the outdoor air ventilation damper of the HVAC system to provide ventilation up to or at the current maximum allowed ventilation rate.

2. The method of claim 1 , wherein the one or more interior environmental conditions include one or more of indoor air temperature, indoor humidity and concentrations of one or more indoor pollutants.

3. The method of claim 1 , wherein the one or more exterior environmental conditions include one or more of outdoor temperature, outdoor humidity and one or more outdoor pollutants.

4. The method of claim 1 , further comprising:
tracking occupancy of the building space over time;
tracking how one or more interior environmental conditions change in conjunction with changes in occupancy; and
learning the environmental model for the building space over time based at least in part on the tracked occupancy of the building space and how the one or more interior environmental conditions changes in conjunction with changes in occupancy.

5. The method of claim 4 , wherein tracking occupancy of the building space over time comprises using one or more of video analytics to analyze one or more video streams to ascertain occupancy of the building space, using sensors to detect occupancy within a zone of the building space, and using sensors to detect individuals entering and/or exiting a zone of the building space.

6. The method of claim 1 , further comprises using the environmental model for the building space to predict how the one or more comfort conditions in the building space is expected to respond to a change in a ventilation rate when predicting the current maximum allowed ventilation rate that can be achieved without exceeding the heating and/or cooling capacity of the HVAC system and without causing the HVAC system to compromise on any of the one or more comfort conditions of the building space.

7. The method of claim 6 , wherein predicting the current maximum allowed ventilation rate comprises inputting to the environmental model one or more of:
a temperature setpoint schedule;
a current humidity setpoint;
a current temperature within the building space;
a current fan status of a fan of the HVAC system;
a current valve status of a valve of the HVAC system;
a current heating and/or cooling load on the HVAC system; and

wherein the current maximum allowed ventilation rate includes a built-in heating and/or cooling capacity margin.

8. The method of claim 1 , further comprising initiating a purge period in which the HVAC system provides a ventilation rate that is above the current maximum allowed ventilation rate for a period of time.

9. The method of claim 8 , wherein the HVAC system is allowed to compromise on one or more of the one or more comfort conditions of the building space during at least part of the purge period.

10. The method of claim 8 , wherein the purge period ends at a time prior to a start of a proscribed period of time sufficient to permit the HVAC system to condition the building space and reach the one or more comfort conditions prior to the start of the proscribed period of time.

11. The method of claim 1 , wherein the environmental model determines a current unused heating and/or cooling capacity of the HVAC system, and wherein the environmental model uses the determined current unused heating and/or cooling capacity of the HVAC system to predict the current maximum allowed ventilation rate that can be achieved without exceeding the heating and/or cooling capacity of the HVAC system and without causing the HVAC system to compromise on any of the one or more comfort conditions of the building space.

12. The method of claim 11 , wherein the environmental model determines a current heating and/or cooling load on the HVAC system, and wherein the environmental model uses the determined current heating and/or cooling load and the determined unused heating and/or cooling capacity of the HVAC system to predict the current maximum allowed ventilation rate that can be achieved without causing the HVAC system to exceed the heating and/or cooling capacity of the HVAC system and without causing the HVAC system to compromise on any of the one or more comfort conditions of the building space.

13. A method for providing a dynamic ventilation rate for a building space using a Heating, Ventilating and/or Air Conditioning (HVAC) system that includes an outdoor air ventilation damper, the method comprising:
tracking over time one or more interior environmental conditions within the building space and one or more exterior environmental conditions outside of the building space during operation of the HVAC system;
learning an environmental model for the building space over time based at least in part on the tracked one or more interior environmental conditions within the building space and the one or more exterior environmental conditions outside of the building space during operation of the HVAC system, wherein the environmental model predicts an environmental state of the building space in response to operation of the HVAC system under various interior and exterior environmental conditions;
determining a dynamic ventilation rate for the HVAC system of the building space based at least in part on inputting to the environmental model of the building space one or more interior environmental conditions and one or more exterior environmental conditions, wherein the determined dynamic ventilation rate is capped at a dynamic maximum allowed ventilation rate that is determined based at least in part on the one or more exterior environmental conditions such that outside air drawn in through the outdoor air ventilation damper at the maximum allowed ventilation rate with the one or more exterior environmental conditions can be conditioned by the HVAC system without exceeding a heating and/or cooling capacity of the HVAC system while maintaining one or more comfort conditions in the

Assignees

• Honeywell Int Inc

Inventors

• Gupta Bhavesh
• Sharma Manish
• Ranjan Prabhat

Classifications

• F24F11/65 Primary

  for selecting an operating mode · CPC title

• F24D19/1048 Primary

  Counting of energy consumption · CPC title

• F24F11/0001

  for ventilation (F24F11/30 takes precedence) · CPC title

• F24F11/47

  Responding to energy costs · CPC title

• G05B19/042

  using digital processors (G05B19/05 takes precedence) · CPC title