JPH0232298A - Nuclear reactor water feed controller - Google Patents

Abstract

PURPOSE:To automate pressure equalizing operation by stopping a signal for increasing the speed of a pump which is driven by a turbine when the pressure difference between the upstream and downstream sides of a valve installed on the downstream side of the pump becomes smaller than a set value. CONSTITUTION:An exit valve 43 is installed on the downstream side of the turbine-driven water feed pump 40 and the pressure 46 at an exist 45 and the pressure 50 of an exist header 49 are detected 44 and 48 respectively to output pressure signals 47 and 51. A computing element 52 calculates the difference between the signals 51 and 47 and outputs a deviation signal 53. A pulse generator 59 inputs the signal 53 and keeps on outputting a pulse signal 61 until the signal 53 is cased, so that a relay 62 for pump controller output setter operation turns on and off repeatedly. A comparator 54 compares the signals 47 and 51 with each other. When the signal 53 becomes smaller than the set value set by the comparator 54, a relay 55 is put in operation to break a contact 58, thereby stopping the output of the generator 59. At the same time, a contact 56 is made to turn on an exit valve opening permission lamp 57, thereby indicating that the opening conditions of the valve 43 are satisfied. Therefore, the equalizing operation is securely performed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a nuclear reactor water supply control device for controlling water supply to a 17;f sub-reactor.

(Prior Art) Water level control in a nuclear reactor is performed by controlling water supply to the reactor. Water is supplied by driving a water pump. In modern plants, water pumps are driven by turbines, e.g.
It consists of two 0% capacity turbine-driven reactor feed water pumps. Furthermore, two motor-driven reactor feed water pumps with a capacity of 25% are installed as auxiliary water pumps.

At the time of reactor startup, the steam pressure is also low, so water is supplied using an electric motor-driven reactor feed water pump.

Then, in order to reach the rated output, the system will be gradually switched to a turbine-driven reactor feed water pump.

The process from starting the turbine-driven nuclear reactor feed water pump to opening the turbine-driven reactor feed water pump outlet valve will be described with reference to FIG. FIG. 3 is a block diagram of a turbine-driven reactor feed water pump control section of a conventional reactor feed water control system. In order to increase the speed of a water supply pump driving turbine (not shown), a speed command signal 2 is outputted from a start-up speed setting device 3 by turning on a speed increasing contact 1. This start-up speed setting device 3 sets the speed increase rate when speeding up the water supply pump driving turbine. The speed command signal 2 is inputted to the start-up lead/lag controller 5 via the speed-up completion contact 4. The start-up lead/lag controller 5 controls the speed of the water pump driving turbine until the water pump driving turbine completes speeding up. The start-up lead/lag controller 5 calculates the speed command signal 2 and the actual speed signal 7 output from the water supply pump driving turbine speed detector 6, and outputs a deviation signal as a lead/lag signal 8. This lead/lag signal 8 is input to a low value selector 9. The low value selector 9 compares the lead/lag signal 8 with the lead/lag signal 11 output from the lead/lag controller 10 for water supply control, and outputs a low value. A signal 12 output from the low value selector 9 is input to a power amplifier 13. This power amplifier 13 is
The signal 12 is converted into a current signal, and the signal is output to an electro-hydraulic converter 14.

When the water supply pump driving turbine speed detected by the water supply pump driving turbine speed detector 6 reaches the set speed, the speed increase completion contact 4 is closed, and the start-up circuit is disconnected to become a water supply control circuit.

The outlet pressure of the turbine-driven reactor feed water pump (not shown) when the set speed is reached is:
It is lower than the outlet header pressure on the bank. Therefore, operators should adjust the pressure at the outlet of the turbine-driven reactor feedwater pump and the header pressure at the reactor feedwater pump so that the outlet pressure of the turbine-driven reactor feedwater pump is approximately -1 to Okg/ffl lower than the header pressure at the outlet of the reactor feedwater pump. Perform pressure equalization operation. An operator operates the turbine-driven nuclear reactor feedwater pump controller output setting device 15, and a water supply command signal 16 is output. This water supply command signal 16 is input to a low value selector 18 via a turbine driven reactor feed water pump controller manual/automatic switching contact 17. This low value selector 18 compares the water supply command signal 16 and the runout setting device output 20 from the runout setting device 19, and outputs the one with the lower signal level. The runout setting device 19 limits the water supply command signal to the turbine-driven reactor feedwater pump so that the flow rate of the turbine-driven reactor feedwater pump does not exceed the runout flow rate. A water supply command signal 21 output from the low value selector 18 is input to a function generator 22 . This function generator 22 is
A water supply command signal 21 is converted into a speed command signal 23 to a turbine-driven reactor feed water pump. This speed command signal 2
3 is input to the adder 25 via the limiter 24, and is calculated with the water supply start bias 27 from the water supply start bias setting device 26, and its output 28 is input to the lead/lag controller 10 for water supply control. . The feed water output start bias setting device 26 is configured to set the lead/lag signal 8 of the drive lead/lag controller 5 and the lead/lag signal 11 of the water supply control lead/lag controller 10 when the feed water pump driving turbine completes speed increase. The bias signal output to the water supply control lead/lag controller 10 is set so that the values are the same. The output 28 input to the water supply control lead/lag controller 10 is output to the low value selector 9. The signal is transmitted to the electro-hydraulic converter 14 via the power amplifier 13. This increases the speed of the feed water pump driving turbine and increases the outlet pressure of the turbine driven reactor feed water pump.

Then, the pressure equalization operation is completed when the deviation from the reactor feed water pump outlet header pressure becomes approximately -1 to 0 kg/cd, and the reactor feed water pump outlet valve for turbine drive (not shown) is
The condition for opening is satisfied. After opening of the turbine-driven reactor feedwater pump outlet valve, reactor injection of feedwater by the turbine-driven reactor feedwater pump begins.

In FIG. 3, reference numeral 28 is a manual operation relay for a turbine-driven nuclear reactor feed water pump controller output/setting device, and reference numeral 29 is a main water supply controller. This main water supply controller 29 outputs a water supply command signal to lower controllers (turbine-driven nuclear reactor feed water pump controller, motor-driven reactor feed water pump controller) of the main water supply controller 29.

(Problem to be solved by the invention) When the pressure equalization operation is performed manually, the turbine-driven reactor feed water pump outlet valve force may be higher than the reactor feed water pump outlet header pressure due to operator error or judgment error. If the outlet valve of the turbine-driven reactor feed water pump is opened under such conditions, water will be incorrectly supplied to the reactor, causing fluctuations in the water level. On the other hand, if the outlet pressure of the turbine-driven reactor feed water pump is too low, the start of water supply from the turbine-driven reactor feed water pump will be delayed and the pump switching time will be longer. When switching pumps,
Since the water level is controlled by two pumps with different characteristics, the control system is vulnerable to disturbances, so the shorter the switching time, the better. Furthermore, from the start of the turbine-driven reactor feedwater pump to the turbine-driven reactor feedwater pump outlet valve-related operations, other than pressure equalization, only the 0N10FF control switch is used, and all other operations are automatically performed by computer. Therefore, only the pressure equalization operation is a manual operation in a series of automation, which is not easy to use and increases the burden on the operator.

The purpose of the present invention is to provide a reactor water supply control system that can reduce the burden on operators by automatically performing pressure equalization operations, prevent erroneous operations, and improve reactor safety. be.

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above object, in the present invention, a first pump that supplies coolant to a reactor pressure vessel and is driven by an electric motor, and a a second wafer pump that supplies water and is driven by a turbine; a valve installed downstream of this second pump; and a valve installed between this valve and the second pump that receives a first pressure signal. a first pressure detector that outputs an output; a second pressure detector installed downstream of the valve that outputs a second pressure signal; and a signal generating means that outputs a signal that increases the speed of the second pump. and signal comparison means for stopping the signal output from the signal generation means when the difference in value between the first pressure signal and the second pressure signal falls within a set value. Provides a nuclear reactor water supply control system.

(Function) In the device configured in this way, the speed of the second pump driven by the turbine is increased by the signal output from the signal generating means, thereby increasing the value of the first pressure signal. Then, when the difference between the values of the first and second pressure signals becomes within a preset value, the signal comparison means stops the signal output from the signal generation means, so that the pressure equalization operation is automatically performed. It is possible to do so.

(Embodiment) Hereinafter, an embodiment of the reactor feed water control device according to the present invention will be described with reference to FIGS. 1 and 2.

FIG. 1 is a configuration diagram of one embodiment. The turbine-driven nuclear reactor feed water pump 40 is driven by a feed water pump driving turbine 41 . This water supply pump driving turbine 41 receives a water supply pump driving turbine drive signal 42 as input. On the downstream side of the turbine-driven reactor feed water pump 40,
A turbine-driven reactor feedwater pump outlet valve 43 is installed. Turbine driven reactor feed water pump outlet pressure detector 4
4 inputs the turbine-driven reactor feed water pump outlet pressure 46 of the turbine-driven reactor feed water pump outlet 45 and outputs a turbine-driven reactor feed water pump outlet pressure signal 47.

The reactor feed water pump outlet header pressure detector 48 inputs the reactor feed water pump outlet header pressure 50 of the reactor feed water pump outlet header 49 and outputs a reactor feed water pump outlet header pressure signal 51. The computing unit 52 subtracts the reactor feed water pump outlet header pressure signal 51 and the turbine-driven reactor feed water pump outlet pressure signal 47 to obtain a pressure deviation signal (Δ
P)53 is output. The pulse generator 59 generates ΔP
(53) is input through the contact 58 and the speed-up completion contact 60,
The pulse signal 61 continues to be output until ΔP (53) disappears. This pulse signal 61 causes the turbine-driven reactor feedwater pump controller output setting device operation relay 62 to go to 0N1.
Repeat 0FF. Signal comparator 54 compares turbine-driven reactor feedwater pump outlet pressure signal 47 and reactor feedwater pump outlet header pressure signal 51 . The outlet valve open permission relay 55 has a signal comparator 54 whose ΔP (53) is
When the value is within the set value set in , it is energized and contact 5
6 is turned on to light the exit permission lamp 57, and at the same time, the contact 58 is cut to stop the output of the pulse generator 59.

Next, the operation of this embodiment will be explained with reference to FIG.

To start the turbine-driven reactor feedwater pump 40 of FIG. 1, the speed-up contact 70 is turned on. When the speed increase contact 70 is turned on, a speed command signal 71 is outputted from the startup waiting speed setter 72. A six-speed command signal 71 is inputted to the startup lead/lag controller 73 via the speed increase completion contact 60. The start-up lead/lag controller 73 uses the speed command signal 71 and the actual speed signal 7 output from the water supply pump driving turbine speed detector 74.
5 and outputs a deviation signal as a lead/lag signal 76. This lead/lag signal 76 is input to a low value selector 77. The low value selector 77 selects the lead/lag signal 76 and the lead/lag signal 79 output from the lead/lag controller 78 for water supply control.
Compare with and output the lowest value. A signal 80 output from the low value selector 77 is input to a power amplifier 81. This power amplifier 81 converts the signal 80 into a current signal,
A signal is output to the electro-hydraulic converter 82 to speed up the water supply pump driving turbine 41 shown in FIG. When the water supply pump drive turbine speed detected by the water supply pump drive turbine speed detector 74 reaches the set speed, the speed increase completion contact 6
0 is input, the start-up circuit is disconnected and becomes the water supply control circuit.

Next, a description will be given with reference to FIG. When the speed-up completion contact 60 is closed, ΔP (53) is input to the pulse generator 59. Here, for example, if the turbine-driven reactor feed water pump outlet pressure 46 after completion of speed increase is 65 kg/cd, and the reactor feed water pump outlet header pressure 50 is 70 kg/aJ,
The calculator 52 calculates the reactor feed water pump outlet header pressure signal 51 - the turbine-driven reactor feed water pump outlet pressure signal 47, and calculates ΔF (53
) is input to the pulse generator (59). The pulse generator 59 generates a pulse signal 61 until ΔP (53) disappears.
Continue to produce. The pulse signal 61 turns on the turbine-driven reactor feed water pump controller output setting device operation relay 62.
/ Repeat OFF.

In FIG. 2, the turbine-driven reactor feed water pump controller output setter 83 increases and outputs the water supply command signal 84 when the turbine-driven reactor feed water pump controller output setter operation relay 62 is turned on, and outputs an increased water supply command signal 84 when it is turned off. Preserve output. The water supply command signal 84 is input to a low value selector 86 via a turbine driven reactor feed water pump controller manual automatic switching contact 85. This low value selector 86 compares the water supply command signal 84 and the runout setter output 88 from the runout setter 87, and outputs the one with the lower signal level. Low value selector 8
The water supply command signal 89 output from the function generator 90
and is converted into a speed command signal 91. This speed command signal 91 is input to an adder 93 via a limiter 92, and is calculated with a feed water start bias 95 from a feed water start bias setting device 94, and its output 96 is sent to a lead/lag controller 78 for water feed control. is input. The output 96 input to the water supply control lead/lag controller 78 is a low value selector 77;
The signal is transmitted to the electro-hydraulic converter 82 via the power amplifier 81, and becomes the turbine drive signal 42 for driving the water supply pump shown in FIG.

In addition, the reference numeral 97 in FIG. 2 is a manual operation relay for the turbine-driven reactor feed water pump controller output setting device, and the reference numeral 98 is
is the water supply main controller.

In FIG. 1, a turbine drive signal 4 for driving a water supply pump is shown.
2 increases the speed of the water pump driving turbine 41. As the speed of the feed water pump driving turbine 41 increases, the turbine driven nuclear reactor feed water pump outlet pressure 46 also increases,
ΔP (53) gradually decreases.

When ΔP (53) is less than the set value set by the signal comparator 54 (-1 to Okg/cd), the outlet valve opening permission relay 55 is activated, the contact 58 is cut off, and the pulse generator 59 is activated. Stop output. At the same time, the contact 56 is closed and the outlet valve opening permission lamp 57 lights up, indicating to the operator that the conditions for opening the outlet valve have been met.

In this example, since the pressure equalization operation is automated, the pressure equalization operation is performed reliably, and when the outlet valve of the turbine-driven reactor feed water pump is opened, incorrect water supply to the reactor due to excessive pressure increase, insufficient pressure increase, etc. This can prevent the delay in the start of water supply from the turbine-driven nuclear reactor feed water pump due to this. Moreover, the electric motor/turbine switching time can be shortened. Furthermore, it is possible to prevent water level disturbance when adding the second port of the turbine-driven nuclear reactor feed water pump.

Since the outlet valve opening permission lamp is installed, it is possible to prevent the operator from accidentally opening the outlet valve.

Note that the present invention can be applied even when the electric motor/turbine switching operation is not automated by a computer, and even in that case, the pressure equalization operation can be performed automatically, so the burden on the operator can be reduced.

〔Effect of the invention〕

According to the present invention, since the pressure equalization operation can be performed automatically, the burden of N transposition can be reduced, erroneous operations can be reduced, and the safety of the nuclear reactor can be improved.

[Brief explanation of the drawing]

1 and 2 show an embodiment of the reactor feed water control device according to the present invention, FIG. 1 is a configuration diagram thereof, FIG. 2 is a block diagram of a turbine-driven reactor feed water pump control section, and FIG. The figure is a block diagram of a conventional turbine-driven nuclear reactor feed water pump control section. 40... Turbine-driven reactor feed water pump 43... Turbine-driven reactor feed water pump outlet valve 44... Turbine-driven reactor feed water pump outlet pressure detector 47... Turbine-driven reactor feed water pump outlet pressure signal 48 ... Reactor feed water pump outlet header pressure detector 51
...Reactor feed water pump outlet header pressure signal 52...
Arithmetic unit 54...Signal comparator 55...Outlet valve opening permission relay 58...Contact 59...Pulse generator 63...Turbine drive reactor feed water pump controller output setter operation relay 83. ...Turbine-driven reactor feed water pump controller output setting device Representative Patent attorney Noriyuki Ken Yudo Daishimaru Ken Figure 2 Figure 1

Claims (1)

[Claims] a first pump that supplies coolant to the reactor pressure vessel and is driven by an electric motor; a second pump that supplies coolant to the reactor pressure vessel and is driven by a turbine; and a downstream pump of the second pump. a first pressure sensor installed between the valve and the second pump to output a first pressure signal; and a first pressure detector installed downstream of the valve to output a second pressure signal. a second pressure detector that outputs a signal, a signal generating means that outputs a signal that increases the speed of the second pump, and a set value that is a difference between the values of the first pressure signal and the second pressure signal. 1. A nuclear reactor feed water control device comprising: signal comparing means for stopping the signal output from the signal generating means when the signal becomes less than or equal to the signal generating means.