Add/shed load control using anticipatory processes

• US 4,916,328 A
• Filed: 12/08/1988
• Issued: 04/10/1990
• Est. Priority Date: 12/08/1988
• Status: Expired due to Term

• Current Assignee: Honeywell Incorporated (Honeywell International Inc.)
• Original Assignee: Honeywell Incorporated (Honeywell International Inc.)
• Inventors: Culp, Charles H. III
• Primary Examiner(s): Shoop, Jr., William M.
• Assistant Examiner(s): Logan, Sharon D.
• Application Number:
  US07/282,097
• Time in Patent Office: 488 Days
• Field of Search: 307/39, 307/38, 364/492, 364/493
• US Class Current: 307/39
• CPC Class Codes: H02J 2310/54 according to a pre-established time schedule
• CPC Class Codes: H02J 2310/60 Limiting power consumption in the network or in one section of the network, e.g. load shedding or peak shaving
• CPC Class Codes: H02J 3/14 by switching loads on to, or off from, network, e.g. progressively balanced loading
• 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

Abstract

There is disclosed an add/shed system and method for adding and shedding loads to maintain the power consumption of a building below the predetermined level. The system includes a plurality of loads and measures the present total power consumption of the building. Selected ones of the loads are reactively shed in response responsive to the measured total power consumption of the building to maintain the present power consumption of the building below the predetermined level. The anticipated future increase or decrease in power consumption of the building is determined and selected ones of the loads are added or shed in response responsive to the measured total power consumption of the building and the anticipated future increase or decrease in power consumption of the building for continuously maintaining the power consumption of the building below the predetermined level.

Claims

1. An add/shed system for adding/shedding loads to maintain the power consumption of a building below a predetermined level, said system comprising:

a plurality of loads;

measuring means for measuring the present total power consumption of said building;

first means for shedding selected ones of said loads responsive to said measured present total power consumption of said building to maintain the present power consumption of said building below said predetermined level; and

second means for determining the anticipated future increase or decrease in power consumption of said building and for adding/shedding selected ones of said loads responsive to said measured present total power consumption of said building and said anticipated future increase or decrease in power consumption of said building for continuously maintaining the power consumption of said building below said predetermined level, wherein said second means is arranged to determine the anticipated future increase or decrease in power consumption by determining which of said loads will be required on or off during a preselected time interval and by determining which of said loads will be requested on or off during a preselected time interval.

2. A system as defined in claim 1 wherein said system is arranged to shed loads when the power consumption of said building reaches a second predetermined level, said second predetermined level being less than said predetermined level.

3. A system as defined in claim 2 wherein said system is arranged to add loads when the power consumption of said building falls to a third predetermined level, said third predetermined level being less than said second predetermined level.

4. A system as defined in claim 1 wherein said system adds/sheds loads during each of a plurality of successive discrete time intervals.

5. A system as defined in claim 4 wherein said second means is arranged for reactively shedding loads based upon power consumption in a present time interval and for predictively adding/shedding loads in the next time interval based upon anticipated increases or decreases in power consumption determined in said present time interval.

6. A system as defined in claim 1 wherein said second means is arranged for delaying the adding of a given load until said given load can be added without the power consumption of said building exceeding said predetermined level.

7. A system as defined in claim 1 wherein each of said loads is assigned a priority with respect to each of the other loads and wherein said first and second means adds/sheds said loads in accordance with said priorities.

8. A system as defined in claim 7 wherein one or more of said loads are combined in a group of loads having a given priority and wherein each load of said group is assigned a priority with respect, to each other load of said group.

9. A system as defined in claim 1 wherein each said load is assigned to at least one of multiple types of add/shed sequences, each sequence controlling the adding/shedding of said loads in a different order, and wherein said system includes means for determining which type of the multiple types of add/shed sequence is assigned to each said load.

10. A system as defined in claim 9 wherein said second means is further arranged for adding/shedding each load according to its assigned sequence.

11. A system as defined in claim 1 wherein said system adds/sheds loads during each of a plurality of successive discreet time intervals, and wherein said second means is arranged to determine the anticipated future increase or decrease in power consumption by determining which of said loads will be required or requested on or off during a present time interval.

12. A system as defined in claim 11 wherein said second means is arranged for reactively shedding loads based upon power consumption in a present time interval and for adding/shedding loads during said present time interval based upon anticipated power consumption decreases or increases determined in said present time interval.

13. An add/shed system for adding loads by an ON command for each said load and shedding loads by an OFF command for each said load to maintain the energy consumption of a building below a predetermined level, each load being assigned to at least one of multiple types of add/shed routines, each routine controlling the adding and shedding of said loads in a different sequence, said system comprising:

a plurality of loads; and

processor means connected to said plurality of loads and adapted to be connected to a power meter for determining which of said plurality of loads should be added or shed to maintain the energy consumption of said building below said predetermined level and for determining which type of the multiple types of add/shed routines is assigned to each load, said processor means for adding or shedding each load according to its assigned routine, said processor means also including means for determining in advance of a load ON command for a given load when the adding of said given load will cause the energy consumption of said building to increase above said predetermined level.

14. A system as defined in claim 13 wherein said processor means is further adapted for determining the increase in energy consumption of said building represented by said given load in advance of said ON command for said given load and for shedding one or more of the other loads having a total energy consumption at least equal to the increase in energy consumption of said building represented by said given load prior to said ON command for said given load to eliminate said increase in energy consumption of said building represented by said given load when said given load is added.

15. A system as defined in claim 13 wherein said loads subject to said ON and OFF commands comprise controlled loads, wherein said system further includes non-controlled loads, and wherein said processor is further adapted to monitor the total energy consumption of said building for determining when one or more of said non-controlled loads cause the energy consumption demand of said building to exceed a predetermined level and for shedding one or more of said controlled loads to reduce the energy consumption demand of said building to below said predetermined level.

16. A system as defined in claim 13 wherein said processor is further adapted to delay the ON command for a given load to maintain the energy consumption of said building below said predetermined level.

17. A system as defined in claim 16 wherein said processor is arranged to delay the ON command of said given load until enough of the other loads have been shed to permit said given load to be added without increasing the energy consumption of said building to above said predetermined level.

18. A system as defined in claim 13 wherein said processor means is further arranged to provide a schedule of the ON and OFF command times for said loads and is further arranged for dynamically altering said ON and OFF command schedule in response to the energy consumption of said building.

24. A method as defined in claim 18 including the further step of delaying the adding of a given load until said given load can be added without the power consumption of said building exceeding said predetermined level.

25. A method as defined in claim 18 including the further steps of assigning a priority with to each said load with respect to each of the other loads and adding/shedding said loads in accordance with said priorities.

26. A method as defined in claim 24 including the further steps of combining one or more of said loads in a group of loads, assigning a given priority to said group of loads, and assigning to each load of said group of loads a priority with respect to each other load of said group.

27. A method as defined in claim 18 including the further steps of assigning to each said load at least one of multiple types of add/shed sequences, each sequence controlling the adding/shedding of said loads in a different order, and determining which type of the multiple types of add/shed sequence is assigned to each said load.

28. A method as defined in claim 26 including the further step of adding/shedding each load according to its assigned sequence.

29. A method as defined in claim 18 wherein said loads are added/shed during each of a plurality of successive discreet time intervals, and wherein the anticipated future increase or decrease in power consumption is determined by determining which of said loads will be required or requested on or off during a present time interval.

30. A method as defined in claim 28 wherein said loads are reactively shed based upon power consumption in a present time interval and wherein said loads are predictively shed/added during said present time interval based upon anticipated power consumption decreases or increases determined in said present time interval.

19. A method of adding/shedding selected ones of a plurality of loads to maintain the power consumption of a building below a predetermined level, said method including the steps of:

measuring the present total power consumption of said building;

reactively shedding selected ones of said loads responsive to said measured present total power consumption of said building to maintain the present power consumption of said building below said predetermined level;

determining the anticipated future increase or decrease in power consumption of said building by determining which of said loads will be required on or off during a preselected time interval and by determining which of said loads will be requested on or off during a preselected time interval; and

predictively adding/shedding selected ones of said loads responsive to said measured present total power consumption of said building and said anticipated future increase or decrease in power consumption of said building to continuously maintain the power consumption of said building below said predetermined level.

20. A method as defined in claim 19 wherein said loads are shed when the power consumption of said building reaches a second predetermined level, said second predetermined level being less than said predetermined level.

21. A method as defined in claim 19 wherein said loads are added when the power consumption of said building falls to a third predetermined level, said third predetermined level being less than said second predetermined level.

22. A method as defined in claim 19 wherein said loads are added or shed during each of a plurality of successive discreet time intervals, and wherein the anticipated future increase or decrease in power consumption is determined by determining which of said loads will be required or requested on or off during the next successive time interval.

23. A method as defined in claim 22 wherein said loads are reactively shed based upon power consumption in a present time interval and wherein said loads are predictively shed/added in the next time interval based upon anticipated decreases or increases in power consumption determined in said present time interval.

31. An add/shed system for adding/shedding loads to maintain the power consumption of a building below a predetermined level, said system comprising:

a plurality of loads;

measuring means for measuring the present total power consumption of said building;

first means for shedding selected ones of said loads responsive to said measured present total power consumption of said building to maintain the present power consumption of said building below said predetermined level;

a second plurality of loads;

control means for controlling the turning on and turning off of said second plurality of loads; and

second means for determining the anticipated future increase or decrease in power consumption of said building and for adding/shedding selected ones of said loads responsive to said measured present total power consumption of said building and said anticipated future increase or decrease in power consumption of said building for continuously maintaining the power consumption of said building below said predetermined level wherein said second means is further arranged to alter the control of said second plurality of loads by delaying the turning on of said second plurality of loads by said control means when the turning on of said second plurality of loads would cause the power consumption of said building to exceed said predetermined level.

32. A system as defined in claim 31 wherein said control means is arranged to transmit a request to said second means prior to the turning on or turning off of said second plurality of loads.