Peak demand limiter and sequencer

• US 5,581,132 A
• Filed: 08/04/1995
• Issued: 12/03/1996
• Est. Priority Date: 08/04/1995
• Status: Expired due to Fees

• Current Assignee: Jon D. Chadwick
• Original Assignee: Jon D. Chadwick
• Inventors: Chadwick, Jon D.
• Primary Examiner(s): Shoop, Jr., William M.
• Assistant Examiner(s): PALADINI, ALBERT WILLIAM
• Application Number:
  US08/511,708
• Time in Patent Office: 487 Days
• Field of Search: 307/11, 307/38, 307/39, 307/141, 361/94, 361/62, 361/63, 340/664, 364/492, 315/209 R
• US Class Current: 307/38
• 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

An electrical control system for sensing instantaneous total electrical power consumption being delivered into a facility and for interrupting selected electrical current consuming loads within the facility when the total incoming current consumption exceeds one or more preselected maximum level for a continuous first preselected time period. The system utilizes existing power transmission lines within the facility to sequentially transmit at least two pulsed digital shut down signals on each of at least two phases or legs of transmission lines within the facility to one or more remote shut down units at the end of the continuous time period. Each remote unit then interrupts electrical power to at least one electrical load within the building for a second preselected time period, after which power is restored to the electrical load until the total current consumption again exceeds one of the preselected maximum load levels continuously for the first time period. Where there are numerous electrical loads to be interrupted, each remote unit then sequentially reestablishes electrical power to each electrical load so as to avoid excessive current surge into the facility. The system also includes a fail safe circuit for resetting all remote units in the event of a power outage.

Claims

1. A system for monitoring incoming electric power being consumed in a facility and for interrupting the flow of electric power within the facility to selected power consuming loads when a preselected peak incoming power load is exceeded for a first preselected time period comprising:

first means for producing a power load signal proportional to the instantaneous total incoming amperage flowing into the facility;

a peak demand limiter including;

second means for receiving said power load signal and for providing a load shed control signal after said first preselected time period during which said power load signal has exceeded said preselected peak load;

third means for receiving said load shed control signal and for then sequentially transmitting independent first and second equipment shut-off signals each of short pulsed duration through a first and second phase power transmission line, respectively, of a multi-phase power line within the facility supplying electrical current to an electrical circuit breaker panel within the facility;

said third means also for repeating the sequential transmittal of said first and second shut-off signals through the first and second phase power transmission line;

a remote receiver connected between the circuit breaker panel and a first power consuming load including;

fourth means for receiving each said shut-off signal and for opening a first relay of the first power consuming load to interrupt electrical power being supplied from the circuit breaker panel to the first power consuming load;

fifth means for closing said first relay to restore electrical power to the first power consuming load after a second preselected time period.

2. A system as set forth in claim 1, wherein:

said second means is also for selectively providing an alternate load shed control signal occurring during a different preselected time of day than that of said first load shed control signal and after said first preselected time period during which said power load signal has continuously exceeded an alternate preselected peak load.

3. A system as set forth in claim 2, wherein:

said third means is also for producing a continuous test signal similar to said first and second equipment turn on signals being received by said remote receiver, said test signal for set-up and testing of said system.

4. A system as set forth in claim 1, wherein:

said third means sequentially transmits said first and second shut-off signals and includes means for repeating the sequential signal transmission.

5. A system as set forth in claim 4, wherein:

said third means is also for providing a reset signal to each said remote receiver immediately upon restoration of the incoming electrical power after a power outage.

6. A system for monitoring incoming electric power being consumed in a facility and for interrupting the flow of electric power within the facility to selected power consuming loads when a preselected peak incoming power load is exceeded for a first preselected time period comprising:

first means for producing a power load signal proportional to the instantaneous total incoming amperage flowing into the facility;

second means for receiving said power load signal and for providing a load shed control signal after said first preselected time period during which said power load signal has continuously exceeded said preselected peak load;

third means for receiving said load shed control signal and for then transmitting independent first and second equipment shut-off signals each of short pulsed duration through a first and second phase power transmission line, respectively, of a multi-phase power line within the facility supplying electrical current to an electrical circuit breaker panel within the facility;

said third means also for repeating the sequential transmittal of said first and second shut-off signals through the first and second phase power transmission line;

fourth means connected between the circuit breaker panel and a power consuming load for receiving each said shut-off signal and for opening a first relay of the first power consuming load to interrupt electrical power being supplied from the circuit breaker panel to the first power consuming load;

fifth means for closing said first relay to restore electrical power to the first power consuming load after a second preselected time period.

7. A system for monitoring incoming electric power being consumed in a facility and for interrupting the flow of electric power within the facility to selected power consuming loads when a preselected peak incoming power load is exceeded for a first preselected time period comprising:

first means for producing a power load signal proportional to the instantaneous total incoming amperage flowing into the facility;

a peak demand limiter including;

second means for receiving said power load signal and for providing a load shed control signal after said first preselected time period during which said power load signal has continuously exceeded said preselected peak load;

third means for receiving said load shed control signal and for then transmitting first and second equipment shut-off signals one immediately following the other and each of short pulsed duration through a power transmission line within the facility supplying electrical current to an electrical circuit breaker panel within the facility;

said third means also for repeating the sequential transmittal of said first and second shut-off signals through the first and second phase power transmission line;

a remote receiver connected between the circuit breaker panel and a first power consuming load including;

fourth means for receiving each said shut-off signal and for opening a first relay of the first power consuming load to interrupt electrical power being supplied from the circuit breaker panel to the first power consuming load;

fifth means for closing said first relay to restore electrical power to the first power consuming load after a second preselected time period.