Control system and circuits for distributed electrical power generating stations

• US 5,734,255 A
• Filed: 03/13/1996
• Issued: 03/31/1998
• Est. Priority Date: 03/13/1996
• Status: Expired due to Fees

• Current Assignee: Alaska Science and Technology Foundation
• Original Assignee: Alaska Power Systems, Inc.
• Inventors: Thompson, Scott B., Thomson, William R.
• Primary Examiner(s): Stephan, Steven L.
• Assistant Examiner(s): Ponomarenko, Nicholas
• Application Number:
  US08/615,706
• Time in Patent Office: 748 Days
• Field of Search: 322/7, 322/25, 322/28, 290/2
• US Class Current: 322/7
• CPC Class Codes: H02J 3/38 Arrangements for parallely feeding a single network by two or more generators, converters or transformers

Abstract

A system (30) for providing electrical-power to remote communities (34) widely distributed over an extended geographical area (38) includes a generating station (32) located proximate each of the communities, each generating station supplying only that community to which it is proximate. The generating stations are in electronic communication with a central computer (40). Each generating station includes a plurality of generators (54-56). Each of the generators is controlled by a microprocessor based controller (64). Each controller is arranged to operate the generating station cooperatively with the other controllers associated with other generators in the station, and to assume a supervisory role in doing so by a mutual arbitration procedure among the controllers. Each controller is also arranged to monitor important generator operating parameters and to communicate these parameters to the central computer. Any controller may be reprogrammed by instructions communicated from the central computer, and functions of any controller may be overridden by instructions communicated from the central computer. The controllers include novel signal processing circuits (90 and 85) and logic for improved voltage and frequency regulation. The controllers also include novel circuits (92) and logic for monitoring generator fuel consumption and calculating generator fuel-efficiency therefrom.

Claims

1. An electrical-power generating station supplying a load connected with a user or community providing a varying demand on the load, the generating station comprising:

first, second, and third engine-driven electrical-power generators, each thereof connectable to and disconnectable from the load, such that said generators may be connected alone or in any combination thereof to the load;

first, second, and third programmable controllers, connected with respectively said first, second, and third generators, each of said controllers in electronic communication with the others;

each of said controllers programmed to operate the generator with which it is connected, to monitor the load demand, to monitor selected operating parameters of the generator with which it is connected, and to be able to assume a supervisory function in cooperatively operating any one or both of the other generators, via said controllers connected therewith;

each of said controllers programmed such that only one thereof may have said supervisory function at any instant, and programmed such that if a said controller having said supervisory function relinquishes said supervisory function, another of said controllers will automatically assume that supervisory function;

operational functions of each of said controllers including starting and stopping the generator with which it is associated, connecting that generator to and disconnecting that generator from the load, and controlling the output frequency and voltage of that generator;

monitoring functions of each of said controllers including the load demand; and

said supervisory function including determining which one or combination of said generators is connected to the load to most efficiently satisfy the load demand.

2. The electrical-power generating station of claim 1 further including means connected to said controllers for electronically communicating with a central computer geographically remotely located from the user or community.

3. The electrical-power generating station of claim 2, wherein said supervisory function further includes electronically communicating with active ones of said other controllers to determine said selected generator operating parameters therefrom, and communicating via said electronic communication means with said remote located computer for reporting said selected operating parameters of the generators thereto.

4. The system of claim 3 wherein said supervisory monitoring and operational functions are carried out in accordance with program instructions electronically stored in each of said controllers and wherein said program instructions may be changed in accordance with updating instructions communicated from said remote computer.