JPS61252404A - Controller for quantity of ventilation of superheater - 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 [Technical Field of the Invention] The present invention relates to a superheater ventilation rate control device for controlling the ventilation rate of a superheater disposed in a steam system piping of a fast breeder reactor.

[Technical background of the invention and its problems 1 Generally, a liquid metal-cooled fast breeder reactor plant consists of a primary cooling system that transfers the nuclear energy generated in the liquid metal-cooled fast breeder reactor to an intermediate heat exchanger, and an intermediate cooling system. The main part consists of a secondary cooling system that transfers energy from the heat exchanger to the evaporator, and a water/steam system that uses the energy obtained from the evaporator to drive the steam turbine.

Figure 5 shows an example of a liquid metal sodium cooled fast breeder reactor plant, which is one of such liquid metal cooled fast breeder reactor plants. System 2I3 and water/steam system 3
The main part is composed of.

The primary sodium pipe 1 is provided to transfer the nuclear energy generated in the reactor 4 to the intermediate heat exchanger 115 via liquid metal sodium, and the primary system piping 6 circulates the liquid metal sodium to the reactor 4. An intermediate heat exchanger 5 and a primary system pump 7 are provided in order from the upstream.

The secondary sodium system 2 is installed to transfer the energy obtained in the intermediate heat exchanger 5 to the superheater 8 via liquid metal sodium, and the secondary sodium system 2 is installed to transfer the energy obtained in the intermediate heat exchanger 5 to the superheater 8 through the liquid metal sodium. A superheater 8, an evaporator 1o, and a secondary pump 11 are provided in this order in a secondary system piping 9 that circulates liquid metal sodium.゛The water/steam system 3 is provided to drive the steam turbine 12 with the energy obtained from the superheater 8 and the evaporator 1o. The system piping 13 includes a steam turbine 12, a water supply pump 14,
Evaporator 1o and steam/water separator 15. is provided.

- That is, the steam heated to high temperature through heat exchange in the superheater 8 is guided to the steam turbine 12 through a pipe in which an isolation valve 16, a main steam stop valve 17, and a steam control valve 18 are installed, and drives the steam turbine 12. After that, the water is converted into condensate by the condenser 19, and is led to the feed water pump 14 through the condensate pump 20° and the low pressure feed water superheater 21 in this order.

In addition, a turbine bypass pipe 23 is arranged in the inlet side pipe of the steam turbine 12, which branches from the upstream side of the main steam stop valve 17, has one end connected to the condenser 19, and has a turbine bypass valve 22 inserted therein. ing.

The water led to the feed water pump 14 flows into the evaporator 10 through the high-pressure feed water superheater 24 and the feed water control valve 25, where it is turned into steam, and then flows into the steam water separator 15, where it enters the isolation valve. 26 and is led to the superheater 8.

Note that the superheater 8 is connected to the steam/water separator 15 via the isolation valve 26.
A superheater bypass pipe branched from the upstream side of the isolation valve 26 to a pipe leading to the pipe, one end of which is connected to the upstream side of the isolation valve 16 of the low temperature outlet side pipe of the superheater 8, and a superheater bypass valve 27 is inserted. 28 are arranged.

In the liquid metal sodium cooled fast breeder reactor plant configured as described above, the nuclear energy generated in the reactor 4 is transferred to the steam turbine via the primary sodium system 1, the secondary sodium system 2, and the water/steam system 3. It is used as energy to drive 12.

However, in a fast breeder reactor power plant configured as above, when increasing the ventilation amount of the superheater 8, it is done while maintaining the heat balance around the evaporator 10 in accordance with the addition of reactor thermal output jv. Conventionally, control has been carried out by keeping the sodium temperature at the outlet of the superheater at a predetermined value. Superheater 8 while maintaining heat balance around 810
It was extremely difficult to increase the amount of ventilation.

[Object of the invention] The present invention has been made in response to such conventional circumstances,
An object of the present invention is to provide a superheater ventilation amount control device that can stably increase the amount of ventilation in the superheater while maintaining the heat balance around the evaporator in accordance with the increase in heat output when increasing the amount of ventilation in the superheater. That is.

[Summary of the invention] That is, the present invention arranges an evaporator, a steam water separator, and a superheater in order from the upstream side in a steam system piping, and in the superheater and evaporator, the coolant and heat flowing through the secondary cooling system piping are disposed. In a superheater ventilation amount control device for controlling ventilation l of a superheater of a fast breeder reactor undergoing exchange, the superheater ventilation m from a flow meter disposed on the superheater exit side of the steam system piping, the secondary cooling Input the superheater inlet side coolant temperature from the temperature detector placed on the superheater inlet side of the system piping and the steam water separator pressure from the pressure gauge placed in the steam water separator, and This is a superheater ventilation amount control device characterized by operating a drain valve l11rtK disposed in a separator.

[Embodiment of the Invention] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

Figure 1 shows the superheater ventilation ffi! of the present invention. II shows the input/output relationship of the all device, and in the figure, reference numeral 13 indicates the water vapor system piping. In this water vapor system piping 13,
An evaporator 10, a steam separator 15, and a superheater 8 are arranged in this order from the upstream side. A drain pipe 29 is connected to the steam/water separator 15, and this drain pipe! ! A drain valve 30 is inserted in 29.

Further, a pressure gauge 31 for measuring the pressure inside the steam/water separator 15 is arranged in the steam/water separator 15 . On the downstream side of the superheater 8 in the steam system piping 13, there is a flow meter 32 for measuring the superheater ventilation amount.
is located.

In the figure, reference numeral 9 indicates a secondary cooling system piping through which a coolant, for example, liquid metal sodium, flows. After that, heat is exchanged with the water supplied from the steam system piping 13 in the evaporator 10.

In the figure, reference numeral 33 indicates a superheater air flow rate control device of the present invention, and this superheater air flow rate control device is configured to control the flow rate of the superheater from the flow meter 32 disposed on the exit side of the superheater 8 of the steam system piping 13. Airflow rate, superheater inlet side coolant temperature from temperature detector 34 placed on the superheater 8 population side of secondary cooling system piping 9, steam/water separation from pressure gauge 31 placed in steam/water separator 15 The opening degree of the drain valve 30 disposed in the steam/moisture vessel 15 is controlled by inputting the vessel pressure. Note that this superheater ventilation amount control device uses computer direct control (DDC) using a digital computer.

Figure 2 shows the details of the superheater ventilation rate control device. In this device, the superheater ventilation rate is set according to a predetermined program based on the input coolant temperature at the inlet of the superheater. The deviation between the airflow rate of the superheater and the airflow m of the superheater measured by the flowmeter 32 is determined, and this deviation signal is subjected to Pr calculation and output to the low value priority circuit (LVG). On the other hand, the deviation between the steam and water separator pressure input from the pressure gauge 31 of the steam and water separator 15 and the pressure setting value is calculated, and this deviation signal is subjected to PI calculation and then output to the low value priority circuit. . From the low value priority circuit, the lower value of the signal based on the superheater air flow rate or the signal based on the steam separator pressure is selected, and this value, after adding the nonlinear compensation fz (X) of the drain valve, is selected. The drain valve 30 of the steam/water separator 15 is operated n degrees.

Figure 3 is a graph showing the function f1(X) of the program shown in Figure 2, where the horizontal axis represents the coolant temperature at the inlet of the superheater, and the vertical axis represents the superheater ventilation rate. , curve a shows /+(X) in FIG.

FIG. 4 shows the flow rate or temperature at each position when the superheater ventilation m is controlled by the superheater ventilation amount control device configured as described above, and time is plotted on the horizontal axis. In other words, the curve in the figure represents the superheater airflow rate,
Curve C shows the coolant temperature on the inlet side of the superheater, curve d shows the coolant temperature on the outlet side of the superheater, and curve e shown by a broken line shows the drain valve flow rate of the steam-water separator 15. As is clear from the figure, the superheater ventilation rate is very well controlled according to the program song Jlla shown in FIG.

In other words, in the superheater ventilation control device configured as described above, the control to increase the superheater ventilation amount in accordance with the temperature rise of the coolant on the inlet side of the superheater is performed by direct computer control. The ventilation amount of the superheater 8 can be stably increased while maintaining the heat balance. Moreover, since it is directly controlled by a computer, nonlinear compensation of the drain valve 30 can be easily performed, and controllability can be improved.

In addition, in the embodiment described above, the computer directly 11Jtll
As a result, since the operator's labor can be reduced and malfunctions can be prevented, the reliability of the control device can be significantly improved compared to the conventional one.

[Effect of the invention 1 As described above, the superheater ventilation fft &lJ of the present invention
According to the III device, the superheater ventilation amount can be stably controlled without operator intervention, and controllability and economical efficiency can be improved. Furthermore, since the temperature of the coolant on the exit side of the superheater can be kept substantially constant, the health of the evaporator and the superheater can be improved.

[Brief explanation of the drawing]

FIG. 1 is a piping system diagram showing the input/output relationship of the superheater ventilation II IIdJ tin device of the present invention, FIG. 2 is a block diagram showing an embodiment of the superheater ventilation amount control device of the present invention, and FIG.
The figure is a graph showing the relationship between the superheater inlet side coolant temperature and the superheater ventilation rate used in the program in Figure 2, and Figure 4 is a graph showing the relationship between the superheater inlet side coolant temperature and the superheater ventilation rate used in the program in Figure 2. The graph showing the ventilation amount, FIG. 5, is a piping system diagram showing a conventional fast breeder reactor plant. 8... Superheater 9... Secondary cooling system piping 10... Evaporator 13... Steam system piping 15... Steam water separation Container 30... Drain valve 31... Pressure gauge 32... Flow meter 34... Temperature detector Patent attorney Suyama Sa - Figure 1 Figure 2

Claims (1)

[Claims] (1) A fast breeder reactor in which an evaporator, a steam separator, and a superheater are arranged in order from the upstream side in the steam system piping, and the superheater and evaporator exchange heat with the coolant flowing through the secondary cooling system piping. In the superheater ventilation rate control device that controls the ventilation rate of the superheater, the superheater ventilation rate from a flow meter disposed on the superheater outlet side of the steam system piping, and the superheater ventilation rate on the superheater inlet side of the secondary cooling system piping. The superheater inlet side coolant temperature from the temperature detector placed in the steam separator and the steam water separator pressure from the pressure gauge placed in the steam water separator are input, respectively, and A superheater ventilation amount control device characterized by controlling the opening degree of a valve.