JPS6395393A - Output controller for nuclear power plant - Google Patents

Abstract

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

Description

[Detailed description of the invention] [Object of the invention] (Industrial application field) The present invention relates to an output control device for a nuclear power plant.

(Prior art) When the number of power outages in the power system increases due to the effects of a typhoon, etc., the load in the power system decreases, the system frequency increases, and power plants trip one after another. Conversely, a phenomenon of power shortage may occur.

In order to avoid such a situation, the central power dispatch center within the power system rapidly reduces the power generation output of a specific power plant.

Conventionally, nuclear power plants deploy a 100% turbine bypass system to suppress reactor thermal output through selective control rod insertion and recirculation pump tripping, while directly restoring main steam through a large-capacity turbine bypass valve. This reduction in power generation output is achieved by discharging the water into the water container.

In addition, in general nuclear power plants that are not equipped with a 100z turbine bypass system, such a reduction in generator output is not normally performed, but if the reactor is scrammed, such a reduction in power generation output can be avoided. It is possible to achieve this.

(Problems to be solved by the invention) However, nuclear power plants equipped with a 100x turbine bypass system have the problem of high construction costs. Once scrammed, there is a problem in that it takes time to start generating power again.

The present invention was made in response to such conventional circumstances, and
To provide an output control device for a nuclear power plant that does not require a 100x turbine bypass system and can rapidly reduce the generator output to a low f in response to a request from a central power dispatch center without requiring a reactor scram. It is something.

In addition to requests from the central power dispatch center, the same applies to load shedding signals generated by plant interlocks when a power system failure occurs.

[Structure of the Invention] (Means for Solving the Problems) That is, the output control device for a nuclear power plant of the present invention includes an output reduction request sending device that sends an output reduction request signal from a central power dispatch center; A request receiving device receives a request signal at a nuclear power plant and outputs a selected control rod insertion signal, a recirculation pump runback signal, a turbine bypass valve open signal, and a relief safety valve open signal in response to the output reduction request signal. There is.

(Function) In the output control device for a nuclear power plant of the present invention, the request receiving device receives an output reduction request signal output from the output reduction request sending device, and the recirculation pump is sent from the request receiving device according to the amount of the output reduction. A planback signal and a selective control rod insertion signal are output to reduce the reactor thermal output, and a turbine bypass valve open signal and relief safety valve open signal are output to activate the response valve and rapidly reduce the main steam flow rate. to rapidly reduce generator output.

(Example) The details of the present invention will be described below with reference to an example shown in the drawings.

The figure shows a nuclear power plant equipped with an output control device for a nuclear power plant according to an embodiment of the present invention, in which a nuclear reactor 1 is housed in a reactor containment vessel 3 equipped with a suppression pool 2. , its output is controlled by adjusting the recirculation flow rate by a recirculation pump 4 and by a control rod 5 inserted from below.
This is done by the operation of

In addition, the reactor 1 is equipped with a plurality of relief safety valves 6 that open when the pressure inside the reactor 1 exceeds a certain level and release the steam inside the reactor 1 into the suppression pool 2. suppress pressure rise.

Steam generated in the reactor 1 is guided to a turbine 9 through a main steam pipe 8 inserted with a main steam control valve 7, and generates electricity a1.
After rotating the water, it is returned to water in the condenser 11 and introduced into the reactor 1 again by the water supply pump 12.

Further, a turbine bypass valve 13 is inserted on the upstream side of the main steam control valve 7 in the main steam piping 8, and a turbine bypass piping 14 bypasses the turbine 9 and directly leads steam from the main steam piping 8 to the condenser 11. is connected, and its bypass capacity is normally 25%.

This nuclear power plant includes an output reduction request sending device 15 which is placed in the central power dispatch center and which sends out an output reduction request signal by operating the operation panel 15a, and which receives this output reduction request signal and outputs A nuclear power plant system comprising a request receiving device 16 that outputs a recirculation pump runback signal, a selective control rod insertion signal, a turbine bypass valve opening signal, and a relief safety valve opening signal according to the amount of reduction, and a valve closing command device 17. An output control device is arranged.

In the output control device for a nuclear power plant having the above configuration, when the operation panel 15a is operated at the central power dispatch center and an output reduction request signal is sent from the output reduction request sending device 15, this signal is transmitted to the nuclear power plant. request receiving device 1
Received at 6. The request receiving device 16 that has received the output reduction request signal determines the amount of output reduction and whether it is rapid or urgent, and
If it is rapid, a recirculation pump runback signal and a predetermined selective control rod insertion signal corresponding to the amount of output reduction are output to reduce the reactor thermal output.

In addition, if the output reduction is urgent, a turbine bypass valve open signal and a relief safety valve open signal are output simultaneously with the above-mentioned recirculation pump runback signal and selected control rod insertion signal to open each valve. The amount of these openings is determined from the required amount of output reduction, and the opening order is such that the turbine bypass valve 13 is opened first, and then the relief safety valve 6 is opened.

In a 110OHWe class nuclear power plant, there are 18 safety relief valves 6, and the capacity of the relief valves is approximately 5χ of the main steam flow rate. In addition, since the capacity of the turbine bypass valve 15 is 25X, for example, if a 25g output reduction request is required, the turbine bypass valve 13 is opened, and if a 50% output reduction request is required, the turbine bypass valve 13 is opened and the relief valve is opened. Five safety valves 6 are opened.

In this way, when the turbine bypass valve 13 and the relief safety valve 6 are opened, steam is released outside the reactor 1, so the pressure inside the reactor 1 drops momentarily, but the pressure control system is activated. The main steam M control valve 7 is closed, a predetermined pressure is maintained, the steam supplied to the turbine 9 is reduced, and the power generation output is reduced.

Although FIG. 1 shows an example of an output reduction request, it is of course possible to make more detailed divisions as necessary.

Then, the valve closing command device 17 controls the turbine bypass valve 13
Since it is difficult to measure the turbine steam flow rate when the is open, APRM (
Evaluate the difference between the reactor heat output signal (average output monitor) signal plus a first-order delay and the target output level, and if this becomes smaller than the amount of steam released by the relief safety valve, the request receiving device 16 The relief safety valves 6 are closed one by one. Moreover, after all the relief safety valves 6 are closed,
The opening degree of the turbine bypass valve 13 is adjusted so that steam corresponding to the difference between the target output and the reactor thermal output flows into the turbine bypass valve 13.

When the reactor output signal stops changing, the reactor output is in a steady state, so the bypass valve is fully closed.

After the turbine bypass valve 13 is fully closed,
Adjust the recirculation flow rate to maintain reactor thermal power at the target power level.

In addition, in the case of a rapid output reduction, the relief safety valve 6 is not used, and only the turbine bypass valve 13 is operated to reduce the target output somewhat slowly.Also, in the case of a rapid output reduction, the reactor thermal output is lowered to the target. Once down to the power level, the recirculation flow rate is adjusted to maintain the reactor thermal power at the target power level.

In other words, the nuclear power plant output control device of this embodiment can respond to requests from the central power dispatch center without scramming the reactor 1, even in a normal nuclear power plant that is not equipped with a 100% turbine bypass system. Therefore, the generator output can be rapidly reduced.

Effects of the Invention In other words, in the output control device for a nuclear power plant of the present invention, an output reduction request signal is sent from the output reduction request sending device of the central power dispatch center, and this output reduction request signal is sent to the request receiving device of the nuclear power plant. and outputs a recirculation pump runback signal and a selective control rod insertion signal according to the amount of output reduction to reduce the reactor thermal output, and responds by outputting a turbine bypass valve open signal and a relief safety valve open signal. and rapidly reduce the main steam flow rate, allowing the generator output to be rapidly reduced without requiring a 10oz turbine bypass system and without scramming the reactor.

[Brief explanation of the drawing]

The figure is a configuration diagram showing a nuclear power plant equipped with an output control device for a nuclear power plant according to an embodiment of the present invention. 1...Reactor 4...Recirculation pump 5...Control rod 6...Relief safety valve 13... Turbine bypass valve 15...
...Output reduction request sending device 16...
・Request receiving device procedure ``A1 (formula) February 1988, 13EJ 2, Name of invention Nuclear power plant output control device 3, Relationship with the person making the amendment case ・Patent applicant Japan Atomic Energy Corporation Toshiba Corporation 4, Agent 2-1-5 Kanda Tamachi, Chiyoda-ku, Tokyo Date of amendment order January 21, 1986 (shipment date) 6. Brief explanation of the drawings in the amended specification Column and drawing “Figure 1 is”
and correct it. (2) Amend the drawing as shown in the attached sheet. Father-in-law 1 figure

Claims (2)

[Claims] (1) An output reduction request sending device that sends an output reduction request signal from a central power dispatch center, and a nuclear power plant that receives the output reduction request signal and generates a selective control rod insertion signal and recirculation in response to the output reduction request signal. An output control device for a nuclear power plant, comprising a request receiving device that outputs a pump runback signal, a turbine bypass valve control signal, and a relief safety valve control signal. (2) The output control device for a nuclear power plant according to claim 1, wherein a load shedding signal that occurs when a power system fails is used as the output reduction request signal.