Power control systems and processes

• US 6,157,874 A
• Filed: 10/31/1997
• Issued: 12/05/2000
• Est. Priority Date: 10/31/1997
• Status: Expired due to Term

• Current Assignee: Luminant Generation Company LLC (Vistra Corp.)
• Original Assignee: Basic Resources, Inc (Sempra)
• Inventors: Carlson, John, Tucker, Donald, Cumpton, Ray, Cooley, Edwin Martin
• Primary Examiner(s): Grant, William
• Assistant Examiner(s): Bahta, Kidest
• Application Number:
  US08/962,309
• Time in Patent Office: 1,131 Days
• Field of Search: 700/22, 700/286, 700/295
• US Class Current: 700/295
• CPC Class Codes: H02J 2310/58 The condition being electrical
• CPC Class Codes: H02J 3/144 Demand-response operation of the power transmission or distribution network
• 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

A control system comprises a utility power line; a first meter, a first generator, a second meter and a programmable logic controller. The utility power line provides power. The first meter is positioned to measure power provided by a utility company via the utility power line. The first generator generates additional power. The second meter is positioned to measure power generated by the first generator. The programmable logic controller is in communication with the first meter and the second meter to receive input information. The programmable logic controller is also in communication with the first generator to selectively control the first generator in response to the input information. The programmable logic controller controls the first generator to keep power provided by the utility company via the utility power line below a first amount at a first time. The programmable logic controller also controls load bearing equipment that consumes the power provided via the utility power line and from the first generator. A process of managing power usage of a plant comprises receiving energy pulses; determining actual kWh being delivered by a utility company, during a demand interval; comparing the actual kWh to a preset kWh amount to determine whether actual kWh is greater than the preset kWh amount; and, if the actual kWh is greater than the preset kWh amount, then reducing the amount of power consumed by load bearing equipment. Also, if the actual kWh is greater than the preset kWh amount, then the process increases power generated a generator.

Claims

1. A power control system, comprising:

a utility power line operable to supply electrical power to a local load;

a first meter operable to measure the electrical power supplied by the utility power line to the local load;

a first generator operable to generate electrical power and supply electrical power to the local load;

a second meter operable to measure the electrical power generated by the first generator and supplied to the local load; and

a programmable logic controller operable to receive input information from the first meter and the second meter and to vary the electrical power generated by the first generator based on the input information.

2. The power control system of claim 1, wherein the programmable logic controller is operable to vary the electrical power generated by the first generator to keep the electrical power supplied by the utility power line below a first power level.

3. The power control system of claim 1, wherein the programmable logic controller is operable to vary the electrical power generated by the first generator to keep the electrical power supplied by the utility power line below a first power level during a time interval.

4. The power control system of claim 1, further comprising:

a variable electrical load operable to receive electrical power from the utility power line and the first generator, the programmable logic controller operable to receive input information from the variable electrical load and to vary the variable electrical load based on the input information.

5. The power control system of claim 4, wherein the programmable logic controller is operable to vary the variable electrical load to keep the electrical power supplied by the utility power line below a first power level.

6. The power control system of claim 4, wherein the programmable logic controller is operable to vary the variable electrical load and to vary the electrical power generated by the first generator to keep the electrical power supplied by the utility power line below a first power level during a first time interval.

7. The power control system of claim 6, wherein the programmable logic controller is operable to vary the variable electrical load and to vary the electrical power generated by the first generator to keep the electrical power supplied by the utility power line below a second power level during a second time interval.

8. The power control system of claim 5, wherein the programmable logic controller is operable to vary the variable electrical load to keep the electrical power supplied by the utility power line below a second power level during a time interval.

9. The power control system of claim 4, wherein the variable electrical load is selected from a group consisting of induction furnace, equipment powered by an A.C. motor with an electronic adjustable speed drive, variable speed drive or variable frequency drive, equipment powered by a D.C. motor with electronic adjustable speed drive, variable speed drive with or without engine-generators, and a variable electrical load.

10. A power control device, comprising:

a first meter input operable to receive information on the amount of electrical power supplied by a utility power line to a local load;

a second meter input operable to receive information on the amount of electrical power generated by a first generator and supplied to the local load; and

a programmable logic controller operable to receive input information from the first meter input and the second meter input and to vary the electrical power generated by the first generator based on the input information.

11. The power control device of claim 10, wherein the programmable logic controller is operable to vary the electrical power generated by the first generator to keep the electrical power supplied by the utility power line below a first power level.

12. The power control device of claim 10, wherein the programmable logic controller is operable to vary the electrical power generated by the first generator to keep the electrical power supplied by the utility power line below a first power level during a time interval.

13. The power control device of claim 10, further comprising:

a variable electrical load input operable to receive information on the amount of electrical power supplied to a variable electrical load from the utility power line and the first generator, the programmable logic controller operable to receive input information from the variable electrical load input and to vary the variable electrical load based on the input information.

14. The power control device of claim 13, wherein the programmable logic controller is operable to vary the variable electrical load to keep the electrical power supplied by the utility power line below a first power level.

15. The power control device of claim 13, wherein the programmable logic controller is operable to vary the variable electrical load to keep the electrical power supplied by the utility power line below a second power level during a time interval.

16. The power control device of claim 13, wherein the programmable logic controller is operable to vary the variable electrical load and to vary the electrical power generated by the first generator to keep the electrical power supplied by the utility power line below a first power level during a first time interval.

17. The power control device of claim 16, wherein the programmable logic controller is operable to vary the variable electrical load and to vary the electrical power generated by the first generator to keep the electrical power supplied by the utility power line below a second power level during a second time interval.

18. The power control device of claim 13, wherein the variable electrical load is selected from a group consisting of induction furnace, equipment powered by an A.C. motor with an electronic adjustable speed drive, variable speed drive or variable frequency drive, equipment powered by a D.C. motor with electronic adjustable speed drive, variable speed drive with or without engine-generators, and a variable electrical load.