JPS60197126A - Sole operating method in station - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to the isolated operation of a steam power generation plant, and in particular to a method of isolated operation of a steam power generation plant using a substation of a plant that is composed of several steam power generation units. Regarding.

[Background of the invention]

We will describe the method of independent operation within the plant with the plant configuration shown in the figure. The power generated by the generator 20 is passed through the unit breaker 22 and sent to the Schnitt auxiliary machine via the unit bus 23! At the same time, power is supplied to the grid 32 via the breaker 11, and the breaker 12 and the substation B bus 1
7, and substation B bus 1 via circuit breakers 7, 8.9.
Power is also supplied to other systems 33 through 6. Furthermore, it is also supplied to a station bus 19 which supplies power to the common auxiliary equipment of each unit through circuit breakers 13 and 16.

In such a power generation plant, if an accident occurs in the system 32, the circuit breakers 10, 11 and 12 are opened, and fuel and water supply, etc., are rapidly reduced using only the unit auxiliary power source of the power generation unit 20, and the unit is turned off. Operates independently within the facility. However, in places such as underdeveloped countries where the reliability of the grid is low, an accident in one system instantly spreads to the entire system, often resulting in the loss of all external power sources connected to the power generation plan.

In this case, each unit will be operated independently within the plant, but if the common power supply equipment includes air conditioning equipment, compressor equipment, and cooling water equipment necessary for continued operation of the units,
Power is supplied from the unit bus 22 to the station bus 19 via the breaker 28 to ensure its operation.

However, according to this operating method, the unit lance has a large capacity considering the common power supply, and is extremely uneconomical. Furthermore, since the generators are operated in parallel in a low load region, even if there is an error of 2 to 3%, no-load operation may occur, which affects the life of the turbine.

[Purpose of the invention]

An object of the present invention is to provide an economical and highly reliable in-plant isolated operation method in a power generation plant.

[Summary of the invention]

The key point of the present invention is that when a power generation plant loses external power, a low-frequency relay installed in the substation selects one of the units to be transferred to the plant independently, and The objective is to provide an economical and reliable method of independent operation within a station, which simultaneously maintains the common power source of the station.

[Embodiments of the invention]

In the present invention, isolated operation within the station when external power is lost is performed as follows.

Figure 1 shows a power supply system diagram for the substation of a power plant. In the event that all external power is lost due to an accident on the system side, all circuit breakers 1, 2, 4, 5 connected to the external system will be disconnected. ,10
, 11, 13, and 14. For example, if the generator 20 is automatically selected as the unit that supplies power to the common auxiliary equipment, the generator breaker 12 remains closed and other frost generators Open the circuit breaker 15. In order to operate the breaker at this substation, by supplying the main power from the generator 20 to the system station bus 19 as quickly as possible, the air conditioning equipment, compression equipment, and cooling water equipment necessary for continued operation of the unit will be operated. Since the selection circuit specifies that the unit carries a common percentage source, the fuel amount, water supply amount, and speed load setter values close to the actual negative M( Since it can be done in advance, a good boiler 2 and turbine control 1 can be obtained in isolated operation within the plant.In the figure, 3゜6 is a breaker, 21.25 is a unit transformer,
18.27 is a bus bar, 24 is a generator, 26 is a unit breaker, 29 is a station communication breaker, 30.31 is a power supply system, and 34 is a low frequency relay.

〔Effect of the invention〕

According to the present invention, the station as a whole can perform safe long-term independent operation within the station. No-load operation that affects turbine life can be prevented, and the unit that carries the common equipment load can be specified by the selection circuit, so it is possible to set the required amount of fuel, water supply, and speed load setting device according to the load. Therefore, the boiler/turbine system 1 can be carried out successfully.

[Brief explanation of the drawing]

The figure is a diagram of the power supply system around the substation at the power station where the present invention was developed. 10... Grid breaker, 11.12... Post-power generation breaker, 20... Generator, 21... Unit transformer, 22... Unit breaker, 23... Unit bus bar, 28... ...Station contact breaker, 30...
Power system, 34...Low frequency relay. Agent Patent Attorney Akio Takahashi C) S1 [

Claims (1)

[Claims] 1. In a steam power generation plant that operates independently within the plant, when external power is lost, a substation is used to secure a common load power source for each unit to a selected one generation unit. A method of independent operation within a facility.