Systems and methods for detecting changes in energy usage in a building

• US 10,261,485 B2
• Filed: 10/23/2015
• Issued: 04/16/2019
• Est. Priority Date: 06/22/2009
• Status: Active Grant

• Current Assignee: Johnson Controls Technology Company (Johnson Controls International plc)
• Original Assignee: Johnson Controls Technology Company (Johnson Controls International plc)
• Inventors: Drees, Kirk H., Wenzel, Michael J.
• Primary Examiner(s): Dalbo, Michael J
• Application Number:
  US14/921,889
• Publication Number:
  US 20160041541A1
• Time in Patent Office: 1,271 Days
• CPC Class Codes: G01R 21/133 by using digital technique
• CPC Class Codes: G05B 15/02 electric
• CPC Class Codes: G05B 17/02 electric
• CPC Class Codes: G05B 2219/2642 Domotique, domestic, home control, automation, smart house
• CPC Class Codes: G06Q 10/0637 Strategic management or analysis, e.g. setting a goal or target of an organisation; Planning actions based on goals; Analysis or evaluation of effectiveness of goals
• CPC Class Codes: G06Q 50/06 Energy or water supply
• CPC Class Codes: G06Q 50/163 Real estate management
• CPC Class Codes: H02J 13/00001 characterised by the display of information or by user interaction, e.g. supervisory control and data acquisition systems [SCADA] or graphical user interfaces [GUI]
• CPC Class Codes: H02J 13/00004 characterised by the power network being locally controlled
• CPC Class Codes: H02J 13/00006 characterised by information or instructions transport means between the monitoring, controlling or managing units and monitored, controlled or operated power network element or electrical equipment
• CPC Class Codes: H02J 13/00016 using a wired telecommunication network or a data transmission bus
• CPC Class Codes: H02J 2203/20 Simulating, e g planning, reliability check, modelling or computer assisted design [CAD]
• CPC Class Codes: H02J 2310/12 The local stationary network supplying a household or a building
• CPC Class Codes: Y02B 70/30 Systems integrating technologies related to power network operation and communication or information technologies for improving the carbon footprint of the management of residential or tertiary loads, i.e. smart grids as climate change mitigation technology in the buildings sector, including also the last stages of power distribution and the control, monitoring or operating management systems at local level
• CPC Class Codes: Y02B 70/3225 Demand response systems, e.g. load shedding, peak shaving
• CPC Class Codes: Y02B 90/20 Smart grids as enabling technology in buildings sector smart grids supporting the management or operation of end-user stationary applications in general, or like technologies with no associated climate change mitigation effect Y04S20/00
• CPC Class Codes: Y02E 60/00 Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
• CPC Class Codes: Y04S 20/00 Management or operation of end-user stationary applications or the last stages of power distribution; Controlling, monitoring or operating thereof
• CPC Class Codes: Y04S 20/20 End-user application control systems
• CPC Class Codes: Y04S 20/221 General power management systems
• CPC Class Codes: Y04S 20/222 : Demand response systems, e.g. load shedding, peak shaving
• CPC Class Codes: Y04S 40/12 : characterised by data transport means between the monitoring, controlling or managing units and monitored, controlled or operated electrical equipment
• CPC Class Codes: Y04S 40/124 : using wired telecommunication networks or data transmission busses
• CPC Class Codes: Y04S 40/20 : Information technology specific aspects, e.g. CAD, simulation, modelling, system security

Abstract

A computer system for use with a building management system for a building includes a processing circuit configured to automatically identify a change in a building'"'"'s energy usage model based on data received from the building management system. The processing circuit may be configured to communicate the identified change in the static factor to at least one of (a) a module for alerting a user to the identified change and (b) a module for initiating an adjustment to the energy model for a building in response to the identified change.

Claims

1. A building management system comprising:

a plurality of sensors measuring a physical state or condition of a building and generating sensor data indicating the physical state or condition measured by the plurality of sensors; and

a controller that uses first sensor data from the plurality of sensors collected during a first time period to generate one or more first model coefficients for an energy usage model for the building;

wherein the controller uses second sensor data from the plurality of sensors collected during a second time period to generate one or more second model coefficients for the energy usage model;

wherein the controller calculates a difference between the first model coefficients and the second model coefficients, generates a test statistic based on the difference, and compares the test statistic with a critical value;

wherein the controller automatically identifies a change in the building'"'"'s energy usage and updates the energy usage model by replacing the first model coefficients with the second model coefficients in response to the test statistic exceeding the critical value;

wherein the controller uses the energy usage model with the second model coefficients to generate and transmit control signals to building equipment that operate to affect the physical state or condition of the building in response to replacing the first model coefficients with the second model coefficients.

2. The building management system of claim 1, wherein:

the first and second model coefficients are regression coefficients; and

the controller generates the first and second model coefficients by performing regression processes using the first and second sensor data.

3. The building management system of claim 1, wherein the test statistic represents at least one of:

the difference between the first and second model coefficients;

an F-statistic that is related to the difference between the first and second model coefficients; and

a Z-statistic that is formed by standardizing the F-statistic.

4. The building management system of claim 1, wherein the controller generates a different set of model coefficients for each of a plurality of windows of time, calculates a test statistic for each different set of model coefficients, determines an autocorrelation of a plurality of the test statistics for the plurality of windows of time, and uses the autocorrelation to determine whether the energy usage model with each different set of model coefficients has changed in a way that affects energy usage.

5. The building management system of claim 1, wherein the first time period is prior to implementing an energy conservation measure and the second time period is after implementing the energy conservation measure.

6. The building management system of claim 1, wherein the controller:

determines an additional cost or savings attributable to the identified change in the building'"'"'s energy usage model; and

uses the additional cost or savings to adjust the energy usage model with the second model coefficients to provide an accurate calculation of savings attributable to an energy conservation measure.

7. A building management system comprising:

a controller that uses first data from the building management system collected during a first time period to generate a first energy usage model for a building;

wherein the controller uses second data from the building management system collected during a second time period to generate a second energy usage model for the building;

wherein the controller compares coefficients of the first energy usage model with coefficients of the second energy usage model, calculates a difference between the coefficients of the first energy usage model and the coefficients of the second energy usage model, and determines that a change affecting the building'"'"'s energy usage has occurred and replaces the first energy usage model with the second energy usage model based on the difference;

wherein the controller uses the second energy usage model to generate and transmit control signals to building equipment that operate to affect a physical state or condition of the building in response to replacing the first energy usage model with the second energy usage model.

8. The building management system of claim 7, wherein:

the coefficients of the first and second energy usage models are regression coefficients; and

the controller generates the coefficients of the first and second energy usage models by performing regression processes using the first and second data from the building management system.

9. The building management system of claim 7, wherein the controller:

gathers third data from the building management system in response to a determination that a change affecting the building'"'"'s energy usage has occurred; and

uses the third data gathered after the change has occurred to generate a third energy usage model for the building.

10. The building management system of claim 9, wherein the controller uses the third energy usage model to generate and transmit updated control signals for the building equipment.

11. The building management system of claim 7, wherein comparing coefficients of the first and second energy usage models comprises generating a test statistic representing at least one of:

a difference between the coefficients of the first energy usage model and the coefficients of the second energy usage model;

an F-statistic that is related to the difference between the coefficients of the first energy usage model and the coefficients of the second energy usage model; and

a Z-statistic that is formed by standardizing the F-statistic.

12. The building management system of claim 11, wherein the controller determines an autocorrelation of a plurality of test statistics for varying windows of time and uses the autocorrelation to determine whether a change that affects energy usage has occurred.

13. The building management system of claim 7, wherein the first time period is prior to implementing an energy conservation measure and the second time period is after implementing the energy conservation measure.

14. The building management system of claim 7, wherein the controller:

determines an additional cost or savings attributable to the identified change in the building'"'"'s first or second energy usage model; and

uses the additional cost or savings to adjust at least one of the first energy usage model and the second energy usage model to provide an accurate calculation of savings attributable to an energy conservation measure.

15. A building management system comprising:

a controller that uses first data from the building management system collected during a first time period to generate a first resource consumption model for a building;

wherein the controller uses second data from the building management system collected during a second time period to generate a second resource consumption model for the building;

wherein the controller compares coefficients of the first resource consumption model with coefficients of the second resource consumption model, calculates a difference between the coefficients of the first resource consumption model and the coefficients of the second resource consumption model, and determines that a change affecting the building'"'"'s resource consumption has occurred and replaces the first resource consumption model with the second resource consumption model based on the difference;

wherein the controller uses the second resource consumption model to generate and transmit control signals to building equipment that operate to affect a physical state or condition of the building in response to replacing the first resource consumption model with the second resource consumption model.

16. The building management system of claim 15, wherein the resource consumption model corresponds to at least one of water usage, gas usage, and electrical energy usage.

17. The building management system of claim 15, wherein:

the coefficients of the first and second resource consumption models are regression coefficients; and

the controller generates the coefficients of the first and second resource consumption models by performing regression processes using the first and second data from the building management system.

18. The building management system of claim 15, wherein the controller:

gathers third data from the building management system in response to a determination that a change affecting the building'"'"'s resource consumption has occurred; and

uses the third data gathered after the change has occurred to generate a third resource consumption model for the building.

19. The building management system of claim 18, wherein the controller uses the third resource consumption model to generate updated control signals for the building equipment.

20. The building management system of claim 15, wherein comparing coefficients of the first and second resource consumption models comprises generating a test statistic representing at least one of:

a difference between the coefficients of the first resource consumption model and the coefficients of the second resource consumption model;

an F-statistic that is related to the difference between the coefficients of the first resource consumption model and the coefficients of the second resource consumption model; and

a Z-statistic that is formed by standardizing the F-statistic.