Distributed control system

• US 5,553,003 A
• Filed: 03/11/1993
• Issued: 09/03/1996
• Est. Priority Date: 03/11/1992
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Saitou, Tadayoshi, Harada, Yasushi, Kokai, Yutaka, Tamura, Shigeru, Kawakami, Junzo, Fukui, Chihiro, Katayama, Yasunori
• Primary Examiner(s): Voeltz, Emanuel T.
• Assistant Examiner(s): Wachsman, Hal D.
• Application Number:
  US08/029,610
• Time in Patent Office: 1,272 Days
• Field of Search: 364/492, 364/493, 364/495, 364/138, 364/139, 364/132, 364/148, 395/903, 395/904, 395/906, 395/907, 395/914, 395/915, 395/918
• US Class Current: 700/286
• CPC Class Codes: H02J 3/06 Controlling transfer of power between connected networks; Controlling sharing of load between connected networks

Abstract

In a control system equipped with a plurality of subsystems and a supervising subsystem for supervising these subsystems, a subgoal achievement performance is calculated by the subsystem using its own knowledge and its own condition with respect to a subgoal defined by the supervising subsystem, and the supervising subsystem controls a control system by utilizing the knowledge and conditions of the respective subsystems by applying a subgoal execution instruction to the subsystem based upon the calculation result. Since not only the knowledge but also the condition of the subsystems, proper controls can be realized in not only such a case that the supervising goal is directed to a static temporal aspect, but also such a case that the supervising goal contains a temporal element.

Claims

1. A method for controlling a power generating system including a plurality of power generating equipments;

a supervising subsystem; and

communication means for establishing communication between said power generating equipment and said supervising subsystem, all of said plurality of power generating equipment having a condition detecting subsystem for detecting local knowledge related to self performance and self condition of respective ones of said plurality of power generating equipment, and also said supervising subsystem having a supervising goal as said power generating system and large area knowledge required to supervise said power generating system, said method for controlling a power generating system comprising the steps of;

(a) dividing the supervising goal into a plurality of subgoals in said supervising subsystem and transmitting one of said subgoals to all of said plurality of power generating equipment via said communication means;

(b) calculating subgoal achievement performance of the respective subsystem with respect to said one of said subgoals transmitted to all of said plurality of power generating equipment, based upon the self local knowledge regarding the self performance and self condition of respective ones of said plurality of power generating equipment in each of said plurality of subsystems which have received said one of said subgoals transmitted to all of said plurality of power generating equipment, the calculated subgoal achievement performance being transmitted to said supervising subsystem via said communication means from all of said plurality of power generating equipment;

(c) comparing and evaluating said subgoal achievement performance respectively transmitted from all of said plurality of power generating equipment in said supervising subsystem in response to said one of said subgoals transmitted to all of said plurality of power generating equipment;

(d) redividing said supervising goal into further subgoals in said supervising subsystem if said supervision subsystem judges that the supervising goal should be redivided as a result of the comparison and evaluation in step (c), and thereafter reexecuting said steps (a) to (c) with respect to one of the redivided further subgoals; and

(e) selecting, in said supervising subsystem a subsystem which has transmitted most preferable subgoal achievement performance in response to said one of said subgoals transmitted to all of said plurality of power generating equipment and sending a subgoal execution instruction to the selected subsystem if said supervising subsystem judges that the supervising subsystem should not be redivided as a result of the comparison and evaluation in step (c).

2. A method for controlling a power generating system as claimed in claim 1, wherein at least one of said plurality of power generating equipment includes a supervising goal as said control system and large area knowledge required to supervise said control system so that said at least one power generating equipment operates as said supervising subsystem.

3. A method for controlling a power generating system as claimed in claim 2, wherein as said condition in all of the power generating equipment, there is employed information containing a portion of a condensation water temperature, a vapor temperature, a burning condition of a boiler, and an operation condition of a draft system.

4. A method for controlling a power generating system as claimed in claim 1, wherein as said condition in all of the power generating equipment, there is employed information containing a portion of a condensation water temperature, a vapor temperature, a burning condition of a boiler, and an operation condition of a draft system.

5. A power distribution control system comprising:

a plurality of power generating stations each having at least one corresponding power generator;

a control station for supervising said plurality of power generating stations; and

communication means for connecting said plurality of power generating stations with said control station,

wherein;

each of said power generating stations includes means for detecting a condition of said at least one corresponding power generator related to power generation cost of said at least one corresponding power generating station, and local knowledge related to performance of said at least one corresponding power generator;

said control station has a goal of a power generation amount for an entire power distribution control system and global knowledge necessary for supervising said power distribution control system;

said control station divides said goal of power generation amount into a plurality of subgoals of fractional power generation amounts on the basis of said global knowledge, and transmits one of said subgoals to said plurality of power generating stations through said communication means to inquire power generation costs of said plurality of power generating stations;

each of said power generating stations calculates power generation cost assuming that said each power generating station has accomplished said transmitted subgoal by using said detected condition and said local knowledge, and transmits the power generation cost thus calculated to said control station through said communication means; and

said control station selects a power generating station which calculated lowest power generation cost among the power generation costs transmitted and issues a command related to said transmitted subgoal to the selected power generating station.

6. A power distribution control system according to claim 5, wherein, in each of said plurality of power generating stations, said means for detecting a condition of said at least one corresponding power generator detects at least one of a condensate water temperature of said at least one corresponding power generator, a vapor temperature, a burning condition of a boiler, and an operating condition of a draft system.

7. A power distribution control system according to claim 5, wherein at least one of said plurality of power generating stations includes a supervising goal as said control system and large area knowledge required to supervise said overall control system so that said at least one power generating equipment operates as said supervising subsystem.