Automatic power supply load shedding techniques

• US 5,017,799 A
• Filed: 06/30/1989
• Issued: 05/21/1991
• Est. Priority Date: 06/30/1989
• Status: Expired due to Term

• Current Assignee: Avaya Incorporated
• Original Assignee: AT&T, Inc.
• Inventors: Fishman, David A.
• Primary Examiner(s): Scott, J. R.
• Assistant Examiner(s): Osborn, David
• Application Number:
  US07/374,674
• Time in Patent Office: 690 Days
• Field of Search: 307/2, 307/29, 307/31, 307/35, 307/38-41, 307/115, 307/130, 307/131, 307/33, 307/34, 379/2, 379/186, 379/307, 379/322-324, 379/412, 379/413, 340/310 A, 340/310 R, 340/825, 340/825.06, 340/825.07, 340/825.08, 340/825.16, 340/825.22, 364/138-142, 364/492, 364/493, 455/3, 455/4, 455/620, 375/36
• US Class Current: 307/34
• 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

Reducing the power consumption of loads fed by one or more power supplies is achieved by the use of apparatus which determines the power supply output and, upon the occurrence of a predetermined condition, generates a signal to the power-consuming loads. In response to this signal, the loads alter their mode of operation so as to reduce the overall demand on the power supply. Several implementations of this load-shedding technique, which is particularly suitable for use in a communications system, are disclosed.

Claims

1. Automatic power supply load shedding apparatus for reducing the power demand of a power supply of a communication system which feeds at least one load, said load including at least one communications device which is connected to said power supply via an interface circuit, the power consumption of said load varying with each of a plurality of operational modes, said apparatus comprising

means for determining the power output demand of said power supply by tracking the activity states of said communications device in said load, said activity states including on-hook and off-hook;

and

means in said load responsive to said determined demand for altering the operational mode of said load so as to reduce the power demand of said supply.

2. The apparatus of claim 1 wherein said altering means includes a processor which directs a battery feed circuit to alter current supplied to said communications device.

3. The apparatus of claim 1 wherein said determining means is a processor which monitors a battery feed circuit in said interface circuit and determines the power output demand therefrom.

4. The apparatus of claim 1 wherein said determining means includes a voltage detector which monitors an output voltage of said power supply.

5. The apparatus of claim 4 wherein said voltage detector is located in said interface circuit.

6. The apparatus of claim 1 wherein said determining means is a processor located in a central control complex of said communication system and is connected to said load via a bus.

7. The apparatus of claim 6 wherein said processor tracks the activity states of said communications device in said load.

8. The apparatus of claim 6 wherein said processor tracks an inoperative or unplugged activity state of said communications device in said load.

9. The apparatus of claim 1 wherein said determining means is responsive to an over-current signal coupled by said power supply.

10. A method of automatically shedding the output power demand of a power supply in a communication system which feeds at least one load, said load including at least one communications device which is connected to said power supply via an interface circuit, the power consumption of said load varying with each of a plurality of operational modes, said method comprising the steps of

determining the power output deman of said power supply by tracking the activity states of said communications device in said load, said activity states including on-hook and off-hook;

and

altering the operational mode of said load, in response to the determined demand, using apparatus internal to said load, said operational mode alteration reducing the power demand of said supply.