JPS61211605A - Controller for water level of water separator - 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 Industrial Application] The present invention relates to a water setter/master tank water level control device that can correct 247 minutes of water setter/fourth tank water level control based on male rill pressure.

[Conventional technology]

FIG. 3 is a system diagram of a conventional water senoyrator water level control valve. In Fig. 3, when the boiler is started and the wet operation is accelerated, the steam from the furnace outlet 1 is separated into steam and water by the water separator, the steam flows to the primary superheater 3, and the drain reaches its high water level set value 2H or higher. In the case of , the water separator drain level control valve 6 is recovered via the water separator drain level control valve 4 (hereinafter referred to as WD valve). (hereinafter referred to as WL) and is collected in the condenser 5.

Furthermore, if the water level of the water mono 4 regulator 2 is higher than the low water level set value of 2L, it is recovered to the deaerator 9 via the water cenosolator bypass control valve & (hereinafter referred to as WLB valve). be done.

Water level control is performed by the WD valve 4, the WL valve 6, and the WLBLaO2 split range so that the r-len water level of the water monomer 2 is maintained at a specified water level.

In addition, the drain that passes through the WL valve 6 and the main valve 8 is arranged to pass through the additional heater 1o, and this additional heater 10 is connected to the water tank/main heater 2 to 9.
The water is heated by the high-pressure feed water heater 1, and the water is heated by the energy saver 12.
Make sure to supply water to the area.

On the other hand, FIG. 4 is a water level control system diagram of a conventional variable pressure monotube boiler. In this FIG.
The output 14, which has been corrected for its specific gravity, is also added to the adder 15.

Adder 15 receives these outputs 131 and 14 . The subtractor 16 adds the quarter and regulator water level measurement signals 15a.
- Output to 18.

Each of the subtractors 16 to 18 receives a high water level setting signal 19Har19 from the IC generator 19 and 19M and 19L, respectively.
Mm, 19La are added.

Accordingly, in the subtracters 16 to 18, the water level measurement signal 15
m, high water level setting signal 19Hm, medium water level setting signal 19M*
, and the low water level setting signal 19L*, and output signals 115 @ * 17 a + 18 sharp corresponding to the deviation thereof to the controllers 20 to 22, respectively.

Outputs 20 to 22m of controllers 20 to 22 are respectively WD
Valve operator 2B, WL valve operator 24, WLB valve operator 25
These WD valve operator 23, WL valve operator 2
4. The output of the WLB valve operating device 25 is used as a control signal to control the closing of the WD valve 4-wire WL valve 6 and wLBLaO2 shown in FIG.

[Problem that the invention seeks to solve]

The water separator water level is controlled by the control system shown in Figure 4 without any problems from the time the ♂ is started to when the ♂ is in operation. When migrating to
At the B signal (FUEL CUT BACK), fuel, water supply, air, etc. are rapidly shut down, and the boiler operation changes from dry operation to wet operation.

At this time, the water level control of quarter 7 and regulator is performed by WL valve 6,
WLBLaO2 water level control is performed, but the pressure at the input is maintained at 170K during Fe2, which is higher than 85K during normal wet operation.

Therefore, if the control gain of quarter 7 and grate water level control is high, WL valve 6 and WLBLaO2 are turned on and water supply II? The water level in Rator 2 causes a hunting phenomenon. This causes pressure fluctuations in the male boiler, which further expands as a disturbance to the boiler water supply control.

In this way, when entering station isolated operation (PCB operation) from boiler high load (dry operation), quarter 7/chillator water level control is controlled by boiler pressure because the control gain changes depending on boiler pressure. It is necessary to correct the gain.

This invention is a ninth attempt to eliminate the above-mentioned conventional drawbacks, and is capable of correcting the control gain due to the irrigating pressure, preventing the notching phenomenon of the water level of the quarter-seven/quarter regulator, and preventing disturbances in the stop-in water supply control. It is an object of the present invention to provide a water level control device for a quarter tank and a water tank that can prevent the expansion of water and provide stable water level control.

[Means for solving problems]

The quarter seiler water level control device of the present invention measures the water level of the quarter seiler, determines the deviations between the measured value and the high water level set value, medium water level set value, and low water level set value, and calculates each deviation. A quarter separator/four-lator water level control device that controls the water level of the water separator/#lator by controlling the opening degree of the quarter seven- and -lator drain valves, the water senorator drain seven-level valve, and the water separator level pipe/fourth valve based on the deviation. , each of the control signals obtained from the respective deviations between the measured value and the medium water level set value and the low water level set value? This circuit is equipped with a circuit that corrects the input pressure setting signal using a control gain signal obtained by a function generator.

[Effect]

This invention uses a function generator in a water tank 4-register water level control device. ), the control gain signal is determined based on the y-in pressure setting signal, and the deviations between the measured water level of the water separator and the medium water level setting value and the low water level setting value are calculated respectively, and the control is calculated from each of these deviations. Each of the signals is corrected with a control gain signal.

〔Example〕

Embodiments of the water separator water level control device of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a control system of one embodiment. In FIG. 1, the same parts as in FIGS. 3 and 4 will be described with the same reference numerals. The output 13th of the water senor f regulator water level transmitter 3 is added to the adder 15, and the output 14a obtained by correcting the specific gravity of the output of the water senor arm pressure transmitter 14 is added to the adder 15. This adder 15 outputs 13h and 1
4a and outputs a water separator water level measurement signal 15h to subtractors 16-18.

Each of the subtracters 16 to 18 includes a signal generator i9H,
A high water level setting signal 19Ha, a middle water level setting signal 19Mm, and a low water level setting value -1% 19 La are input from 19M and 19L, respectively.

As a result, the subtractors 16 to 18 are used for the water level measurement signal 15a, the high water level setting signal 19Hm, and the medium water level setting signal 19, respectively.
Mm and the low water level setting signal 19La are compared, and the deviation signals 16a to 18m are output to the water level controllers 20 to 22.

Each of the water level controllers 20 to 22 corrects the deviation signals 161 to 18 & obtained by the subtractors 16 to 18, and
From 0, a correction signal 20h is output to the WD valve operator 23,
Due to the output of this WD valve operating device 23, as shown in FIG.
The D valve 4 is controlled to collect the drain from the water separator 2 into the condenser 5. The configuration and operation described above are the same as in the conventional case shown in FIGS. 3 and 4.

However, this invention differs from the conventional art in the following points, which are the features of this invention.

That is, in the present invention, the modified signals 21m and 22h modified by the water level controllers 21 and 22 are sent to the multipliers 26 and 22, respectively.
It is scheduled to be sent out on the 27th. These multipliers 2
Control gain signals 2B& and 29* are also input to 6.27 from function generators 28 and 29, respectively.

The function generator 28.29 generates a pressure-based control gain signal 2 based on the pressure setting signal 30 as shown in FIG.
Generates 8m, 29h.

Accordingly, the multipliers 26 and 27 are respectively connected to the water level controller 2.
Modified signal 21a from 1.22.

221 and the control gain signals 211* and 29*,
The calculation results are output to control valve controllers 31 and 32.

The control valve controllers 31.32 each correspond to this multiplier 26.2.
7 is received and output to the WL valve operator 24 and the WLB valve operator 25. The WL valve controller 24 and the WLB valve controller 25 respectively control the WL valve 6 and the WLB valve 8 shown in FIG. Furthermore, when the WLB valve 8 is opened, the drain from the water separator 2 is collected into the deaerator 9.

In this way, what is the water separator water level in response to rapid changes due to isolated operation within the plant from high load? Stable water level control is possible without being affected by inlet pressure.

Therefore, the present invention is effective when applied to a water level control device for a monotube water separator.

〔Effect of the invention〕

As described above, according to the water separator water level control device of the present invention, the control gain signal is obtained by the function generator based on the sibiin pressure setting signal, and the measured value of the water separator water level and the intermediate water level setting value are determined by the function generator. The deviation from the low water level set value is determined, and the control signal determined from each of these deviations is corrected using the control gain signal.
Is it possible to prevent the water level of the water tank/IP regulator from causing hunting phenomenon, and increase the disturbance of the gain pressure fluctuation and in-water supply control? This can be prevented and stable water level control can be performed.

[Brief explanation of drawings]

Fig. 1 is a block diagram of an embodiment of the water separator water level control device of the present invention, and Fig. 2 is a block diagram of an embodiment of the water separator water level control device of the present invention. Figure 3 is a system diagram of the water senor arm water level control valve in a conventional water separator water level control device, and Figure 4 is a water level control system in a conventional water separator water level control device. It is a diagram. 13...Water tank f-rate water level transmitter, 14...
・Water set/4 router pressure transmitter, 15...Adder, 16-18...Subtractor, 19H, 19Vi, 19
L-゛. Signal generator, 20-22... Water level controller, 23...
WD valve operator, 24...WL valve operator, 25...W
LB valve operator, 26.27... Multiplier, 28.29.
...Function generator, 31.32...Control valve controller.

Claims (1)

[Claims] Measure the water level in the water separator, find the deviations between the measured value and the high water level set value, medium water level set value, and low water level set value, and then adjust the water separator drain valve and water separator drain level valve based on each deviation. and a water separator water level control device that controls the water level of the water separator by controlling the opening degree of a water separator level bypass valve, the control determined from the respective deviations between the measured value and the medium water level set value and the low water level set value. A water separator water level control device characterized by incorporating a circuit that corrects each signal using a control gain signal obtained from a boiler pressure setting signal using a function generator.