Rule-based load shedding algorithm for building energy management

• US 10,436,470 B2
• Filed: 07/18/2017
• Issued: 10/08/2019
• Est. Priority Date: 07/18/2017
• Status: Active Grant

• Current Assignee: ABB Schweiz AG (ABB Limited)
• Original Assignee: ABB Schweiz AG (ABB Limited)
• Inventors: Brissette, Alexander, Carr, Joseph A
• Primary Examiner(s): Lee, Thomas C
• Assistant Examiner(s): Collins, Gary
• Application Number:
  US15/653,478
• Publication Number:
  US 20190024918A1
• Time in Patent Office: 812 Days
• CPC Class Codes: F24F 11/30 for purposes related to the operation of the system, e.g. for safety or monitoring
• CPC Class Codes: F24F 11/46 Improving electric energy efficiency or saving
• CPC Class Codes: F24F 11/54 using one central controller connected to several sub-controllers
• CPC Class Codes: F24F 11/62 characterised by the type of control or by internal processing, e.g. using fuzzy logic, adaptive control or estimation of values
• CPC Class Codes: F24F 11/65 for selecting an operating mode
• CPC Class Codes: F24F 2110/10 Temperature
• CPC Class Codes: F24F 2140/50 Load
• CPC Class Codes: F24F 2140/60 Energy consumption
• CPC Class Codes: F24H 9/0005 for water heaters
• CPC Class Codes: G05B 15/02 electric
• CPC Class Codes: G05B 2219/2642 Domotique, domestic, home control, automation, smart house
• CPC Class Codes: H02J 2310/14 The load or loads being home appliances
• CPC Class Codes: H02J 3/14 by switching loads on to, or off from, network, e.g. progressively balanced loading
• CPC Class Codes: H04W 4/33 for indoor environments, e.g. buildings
• CPC Class Codes: H04W 4/38 for collecting sensor information
• CPC Class Codes: H05B 47/11 by determining the brightness or colour temperature of ambient light
• CPC Class Codes: H05B 47/115 by determining the presence or movement of objects or living beings
• CPC Class Codes: H05B 47/165 following a pre-assigned programmed sequence; Logic control [LC]
• CPC Class Codes: Y02B 20/40 Control techniques providing energy savings, e.g. smart controller or presence detection
• CPC Class Codes: Y02B 30/70 Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating
• 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: Y04S 20/222 : Demand response systems, e.g. load shedding, peak shaving
• CPC Class Codes: Y04S 20/244 : the home appliances being or involving heating ventilating and air conditioning [HVAC] units
• CPC Class Codes: Y04S 20/246 : the system involving the remote operation of lamps or lighting equipment

Abstract

Unique systems, methods, techniques and apparatuses of building power management are disclosed herein. One exemplary embodiment is a system comprising a load management controller and a power circuit interrupter. The load management controller is configured to repeatedly perform a first test wherein a time rate of change of temperature of building regions is determined, repeatedly perform a second test wherein a lighting controller is operated to rank a plurality of lighting loads according to ambient light of building regions associated with the plurality of lighting loads, assign the plurality of HVACR loads and lighting loads to a plurality of load shed groups, and reduce power consumption by the plurality of HVACR loads and the plurality of lighting loads in order of the ranked load shed groups effective to minimize occupant perceptibility of the power consumption reduction while implementing the operator specified priority criteria.

Claims

1. A power management system comprising:

a power circuit interrupter operatively coupled with a first subset of a metered plurality of electrical loads, the power circuit interrupter configured to interrupt power to the first subset of the metered plurality of electrical loads in response to a load shed signal; and

a load management controller operatively coupled with a second subset of the metered plurality of electrical loads, the second subset comprising a plurality of building lighting loads and a plurality of building HVACR loads, in operative communication with the power circuit interrupter, and configured to;

repeatedly perform an evaluation of net power consumption of the metered plurality of electrical loads relative to a power consumption criterion,

repeatedly perform a first test wherein operation of the plurality of HVACR loads is suspended and a time rate of change of temperature of building regions associated with respective ones of the plurality of HVACR loads is determined effective to dynamically rank load shedding priority of the plurality of HVACR loads according to their respective time rate of change of temperature,

repeatedly perform a second test wherein a lighting controller is operated to rank a plurality of lighting loads according to ambient light of building regions associated with the plurality of lighting loads, effective to dynamically rank load shedding priority of the plurality of lighting loads according to ambient light of their associated building regions,

assign the plurality of HVACR loads and the plurality of lighting loads to a plurality of load shed groups according to operator specified priority criteria,

rank the plurality of load shed groups using the load shedding priority rank of the plurality of HVACR loads and the load shedding priority rank of the plurality of light loads assigned to each of the plurality of load shed groups, and

generate the load shed signal so as to reduce power consumption by the plurality of HVACR loads and the plurality of lighting loads according to the ranked load shed groups effective to minimize occupant perceptibility of the power consumption reduction while implementing the operator specified priority criteria.

2. The system of claim 1 wherein the second subset includes one or more building water heater loads, and wherein the second load management controller is configured to rank load shedding priority of the plurality of building water heater loads and assign the plurality of building water heater loads to the plurality of load shed groups according to operator specified priority criteria.

3. The system of claim 1 wherein the load management controller is configured to determine an occupancy status for each building region associated with respective ones of the plurality of HVACR loads, and wherein dynamically ranking load shedding priority of the plurality of HVACR loads includes evaluating each determined occupancy status.

4. The system of claim 3 wherein the load management controller determines the occupancy status for each building region associated with respective ones of the plurality of HVACR loads using a motion sensor.

5. The system of claim 1 wherein the load management controller is configured to determine an occupancy status for each building region associated with the plurality of lighting loads, and wherein dynamically ranking load shedding priority of the plurality of lighting loads includes evaluating each determined occupancy status.

6. The system of claim 1 wherein the load management controller is configured to initialize the plurality of load shed groups by using the operator specified priority criterion to assign the plurality of HVACR loads and the plurality of lighting loads initially to one of the plurality of load shed groups.

7. The system of claim 1 wherein the load management controller is configured to increase power consumption of the plurality of HVACR loads and the plurality of lighting loads in reverse order of the ranked load shed groups in response the evaluation of net power consumption of the metered plurality of electrical loads relative to the power consumption criterion.

8. A building power management system comprising:

a building power controller configured to measure power consumption of a building, periodically receive a power consumption target value, and transmit a load shed signal in response to determining the measured power consumption is greater than the power consumption target value,

a power interruption device structured to receive the load shed signal from the building power controller and interrupt the flow of power to a building load in response to receiving the load shed signal from the building power controller,

a load shed controller in communication with the building power controller and a plurality of controllable building loads including at least one of a plurality of HVACR loads each corresponding to one of a plurality of HVACR zones, and a plurality of lighting loads each corresponding to one of a plurality of lighting zones, the controller being configured to;

operate each of the plurality of HVACR loads in a testing mode during which the HVACR load is turned off, the change in temperature of the corresponding HVACR zone between a first time and a second time of a testing time period is measured, and the length of time between the first and the second time is measured,

calculate a rate of temperature change for each of the plurality of HVACR zones using the testing time period length measurement and the change in temperature measurement,

dynamically rank the plurality of HVACR loads according to an occupancy status of each of the plurality of HVACR zones and the calculated rate of temperature change,

dynamically rank the plurality of lighting loads according to an occupancy status of each of the plurality of lighting zones and ambient light conditions,

assign each of the plurality of HVACR loads and each of the lighting loads to at least one of a plurality of ranked shed groups including a first ranked shed group and a second ranked shed group using the rankings of the plurality of HVACR loads, the rankings of the plurality of lighting loads, and operator specified business rules,

reduce power consumption of the building in response to receiving the load shed signal by adjusting an HVACR set point of each of the plurality of HVACR loads assigned to the first ranked shed group and adjusting a lighting set point of each of the plurality of lighting loads assigned to the first ranked shed group, and

further reduce power consumption of the building in response to receiving the load shed signal by adjusting the HVACR set point of each of the plurality of HVACR loads assigned to the second ranked shed group and adjusting the lighting set point of each of the plurality of lighting loads assigned to the second ranked shed group.

9. The system of claim 8 wherein the power consumption target value is received from a utility grid system operator as part of a demand response program.

10. The system of claim 8 wherein the load shed controller adjusts the HVACR set points and lighting set points associated with the second ranked shed group in response to determining the measured power consumption still exceeds the target power consumption value following adjusting the HVACR set points and lighting set points associated with the first ranked shed group.

11. The system of claim 8 wherein the plurality of controllable building loads includes a thermal storage device and the load shed controller is configured to assign the thermal storage device to the first ranked shed group and wherein reducing the power consumption of the building in response to receiving the load shed signal includes reducing the set point of the thermal storage device.

12. The system of claim 8 wherein the building power controller is structured to transmit a load activation command in response to comparing the measured power consumption and a target power restoration value, and wherein the load controller is configured to increase power consumption of the second ranked load shed group in response to the load activation command, and increasing the power consumption of the first ranked load shed group in response to determining the target power restoration value is greater than the measured power consumption following increasing the power consumption of the second ranked load shed group.

13. The system of claim 8 wherein the magnitude of each adjustment to HVACR set points and lighting set points is set using operator specified values.

14. The system of claim 8 wherein each of the plurality of HVAC loads corresponding to an unoccupied HVACR zone is assigned to the first ranked load shed group and each of the plurality of lighting loads corresponding to an unoccupied lighting zone is assigned to the first ranked load shed group.

15. The system of claim 8 wherein the load shed controller is configured to operate each of the HVAC loads in a testing mode and update the calculated rate of temperature change for each of the plurality of HVACR zones periodically.

16. A method for reducing power consumption in a building comprising:

operating a first load management controller configured to perform an evaluation of net power consumption of a metered plurality of electrical loads relative to a power consumption criterion and to send a load shed signal responsive to the evaluation;

operating a power circuit interrupter in operative communication with the first load management controller and operatively coupled with a first subset of the metered plurality of electrical loads, the power circuit interrupter configured to interrupt power to the first subset of the metered plurality of electrical loads in response to the load shed signal; and

operating a second load management controller in operative communication with the first load management controller and operatively coupled with a second subset of the metered plurality of electrical loads, the second subset comprising at least two of a plurality of building lighting loads, a plurality of building HVACR loads, and a plurality of thermal storage loads;

repeatedly performing, with the second load management controller, a first test wherein operation of the plurality of HVACR loads is suspended and a time rate of change of temperature of building regions associated with respective ones of the plurality of HVACR loads is determined effective to automatically and dynamically rank load shedding priority of the plurality of HVACR loads according to their respective time rate of change of temperature;

repeatedly performing, with the second load management controller, a second test wherein a lighting controller is operated to rank a plurality of lighting loads according to ambient light of building regions associated with the plurality of lighting loads, effective to automatically and dynamically rank load shedding priority of the plurality of lighting loads according to ambient light of their associated building regions;

assigning, with the second load management controller, the plurality of HVACR loads and the plurality of lighting loads to a plurality of load shed groups according to operator specified priority criteria;

ranking, with the second load management controller, the plurality of load shed groups using the load shedding priority rank of the plurality of HVACR loads and the load shedding priority rank of the plurality of light loads assigned to each of the plurality of load shed groups, and

reducing, with the second load management controller, power consumption by the plurality of HVACR loads and the plurality of lighting loads in order of the ranked load shed groups effective to minimize occupant perceptibility of the power consumption reduction while implementing the operator specified priority criteria in response to the load shed signal.

17. The method of claim 16 wherein assigning includes determining whether each of the building regions associated with each of the plurality of HVACR loads is occupied, and assigning each of the plurality of HVACR loads associated with an unoccupied building region to the lowest priority load shed group.

18. The method of claim 16 wherein reducing includes adjusting a set point of each HVACR load, lighting load, or thermal storage load associated with the load shed group by an operator specified value.

19. The method of claim 16 wherein the evaluation of net power consumption of the metered plurality of electrical loads relative to the power consumption criterion is performed in real-time.

20. The method of claim 19 wherein the power consumption criterion is modified in response to a demand response signal received from a system operator.