JPS5924102A - Controller for internal water level of steam generator - 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] related to the equipment used.

A steam generator is supplied with water (feed water) that turns into steam. The system uses an appropriate heating source to heat the feed water to evaporate and boil it to obtain steam, but if the water level changes, the internal thermal conditions will change.

This may lead to various problems. This reservoir water level must be properly controlled.

FIG. 1 is a Bronnok diagram of a conventional water level control device, where oi is a steam generator including a feed water flow rate control valve, 02 is a steam flow rate detector, 03 is a water level detector, 04 is a water level setting device, and 0
5 is a subtracter, 06 is a water supply flow rate detector, 07 is a proportional integral regulator, 08.

09 is a subtracter, and 010 is a proportional-integral adjuster.

Such conventional systems have drawbacks such as disturbances in water level fluctuations when one disturbance is applied, noise, etc., and the differential operation cannot be utilized.

The present invention has been made to eliminate the conventional drawbacks, and details thereof will be explained based on illustrated embodiments.

In FIG. 2, the steam generator 1 includes a main body of the steam generator, as well as related devices such as a water supply pipe, a water supply flow rate control valve, and a main steam pipe.

The water level detector 3, water level setting device 5, and subtractor 7 of the steam generator 1 are connected to output a water level deviation signal. The water level deviation signal is continuously input to the main controller, ie, the proportional-integral action regulator 9, and the output of the proportional-integral action regulator 9 is input to the adder 11.

The water supply flow rate signal output from the water supply flow rate detector 13 provided in the water supply pipe enters the subtractor 15 and also enters the arithmetic unit 17 .

The arithmetic unit 17 will be described later.

Steam flow rate detector 1 installed in the main steam pipe of the steam generator 1
The steam flow rate signal output from 9 enters a subtracter 15 and a calculator 17.

In the subtractor 15, the feed water flow rate signal and the steam flow rate signal are subtracted, and a flow rate difference signal is output.

The subtracter 21 is entered.

The computing unit 17 incorporates a dynamic characteristic model of the steam generator l. The dynamic characteristic model is expressed by equation (1).

However, ■ = specific volume of liquid part of steam generator 1 (+n3/Kv) A: surface area of liquid part of steam generator 1 (m2)
/h) X: steam flow rate (Kg/h) t: time (h) 4t): water level (m)
Calculations are performed in real time based on equation (1), and a signal corresponding to the differential value of the water level is output.

The signal corresponding to the differential value passes through the proportional action regulator 23, is multiplied by the proportional gain, and enters the adder 11.

In the adder 11, the output of the proportional-integral action regulator 9 and the output of the proportional action regulator 23 are summed.

It enters a subtracter 21 and is subtracted from the flow rate difference signal.

The output of the subtractor 21 enters the sub-controller, that is, the proportional-integral action regulator 25, and finally becomes the valve opening signal of the flow control valve, which is applied to the flow control valve to control the flow rate of water supplied to the steam generator 1. be done. In this way, the water level inside the steam generator 1 is suitably maintained.

According to the embodiment described above, since the differential operation is added without differentiating the water level, the water supply flow rate control valve is operated after understanding the future behavior of the water level.
Control performance is improved.

The dynamic characteristic model incorporated into the arithmetic unit 17 is as follows.

(It is not limited to Equation 11, but can be made into a more detailed model depending on the required accuracy. For example, when the primary coolant of the nuclear reactor is used as the heating source for the steam generator l, the secondary coolant flow rate is , temperature and the internal pressure of the steam generator 1 can also be used as inputs in addition to the two flow rate signals.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a conventional device, and FIG. 2 is a block diagram of an embodiment of the present invention. ■...Steam generator, 3...Water level detector, 5...Water level setter, 9...Proportional-integral operation regulator, 13... ...Water supply flow rate detector, 17.
......Arithmetic unit, 25...Proportional-integral action regulator

Claims (1)

[Claims] In a device that controls the water supply level in a steam generator connected to a water supply pipe having a flow rate control valve, there is a main controller that receives a water level deviation signal, a main controller that receives a water level deviation signal, and a main controller that receives a difference between the water supply flow rate signal and the steam flow rate signal. a subtractor that receives the output of the main limiter; a sub-controller that receives the output of the subtractor and applies a valve opening signal to the flow rate control valve; and a sub-controller that receives the feed water flow rate signal and the steam flow rate signal. An internal water level of a steam generator, characterized in that the steam generator has an arithmetic unit that outputs a signal corresponding to a differential value of the water level, and applies the signal corresponding to the differential value to the subtracter together with the output of the main feed suppressor. Control device.