JPS60134105A - Flow controller for feedwater - 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 The present invention relates to a feed water flow rate control device, and more particularly to a feed water flow rate control device that can be applied to a pressurized water reactor (PWR) f-rant feed water control device and the like.

A conventional feed water control system for a steam generator of a PWRf runt will be explained with reference to FIG. In FIG. 1, a feed water control device 107 that performs a three-element control operation uses a feed water flow meter 101g, 101b, which is duplicated as a feed water flow rate signal, selected by a manual switch 104, and a steam flow rate signal 18. Duplicated steam flow meter J02a+10
2b selected by the manual switch 105, and steam generator water level gauge 103m, 103b converted to 2x as the steam generator water level signal, selected by the behavior switch 106. The opening degree of the main water supply valve 10B is adjusted according to the process signal so that it matches the desired water level.

The steam generated in the steam generator 109 joins the header line 110 together with the steam from other similarly configured Roogs, and becomes the inflow steam to the turbine 120.

The aforementioned detectors were duplicated and the operator judged which No. 48 was correct and switched manually, but this placed a heavy burden on the transfer staff in the event of a detector failure. Furthermore, there was a risk of malfunction due to misjudgment by the operator.

The present invention was proposed in view of the above circumstances, and its purpose is to provide a water supply flow rate control device that can automatically select a normal detector signal with a minimum equipment scale that takes into account the characteristics of the plant. There is something to do.

The feed water flow rate control device according to the present invention is capable of controlling the feed water flow rate of a plant having a plurality of heating medium circulation loops connected to the same heat supply source and a steam generator having a water supply chamber and a steam outlet, each of which is separately installed in the same heat supply source. In the apparatus, at least two feed water flow rate detectors are provided for each steam generator and are connected to a first automatic selection device; and at least three feed water flow rate detectors are provided for each steam generator and these are connected to a first automatic selection device. a water level detector connected to the selection device; at least two steam flow meters provided for each steam generator and connected to a third automatic selection device; a control device that controls a water supply control valve for each steam generator;
The third automatic selection device is characterized by comprising means for connecting the third automatic selection device to one of the steam flowmeters of the other loop to receive its output, and in a plurality of similar processes, the third automatic selection device is connected to one of the steam flowmeters of the other loop, By using signals in combination, automatic selection of signals can be performed with a minimum detector configuration, thereby solving the drawbacks of the prior art.

- An embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 2 is a block diagram showing the configuration of an embodiment of the present invention, and FIG. 3 is a diagram showing a detector failure diagnosis logic in the embodiment shown in FIG.

In Figure 2, 101m, 101b, 201m.

201b is water supply flow meter, 102m+102b, 202*
.

202b is a steam flow meter, 103a1103b1103c
.

2 (73B + 2 (7J b # 2 (7,3c
is steam generator water level gauge, 104.105,106,204
, 205.206 is a signal automatic selector, 107.207
is the control device, 108゜208 is the main water supply control valve, 109,
209 is a steam starter. The embodiment of the present invention shown in FIG. 2 is a case where the present invention is applied to a water supply flow control device for 2 loops, but the present invention can also be applied to a case of 3 loops or more. It is clear that it is applicable. Note that the loop here refers to the PWH coolant circulation system (C1osed 1loop), and the number of loops (
For example, 2 loops) corresponds to the number of steam generators (for example, 2).

The configuration of loop 1 shown in FIG. 2 will be explained below.
The same applies to loop 2. The feed water flow rate signal automatic selector 104 includes dual feed water flow meters 101m and 101b that detect the feed water flow rate.

and the three signals of the steam flow meter 102* in the same loop are used to automatically select a normal signal. In addition, the steam flow rate signal automatic selector 105 includes dual steam flowmeters 102m and 102 that detect the steam flow rate.
A normal signal is automatically selected using three signals from the steam flowmeter 202b and the steam flowmeter 202b of the other loop. The steam generator water level signal automatic selector 106 includes triplex steam generator water level gauges 103 a I" 103 b
*103c The control device 107 includes automatic signal selectors 104 and 105 to select a normal signal.

In response to the normal process signals selected by 106, such as a water supply flow rate signal, a steam flow rate signal, and a steam generator water level signal, a three-element control operation is performed to provide an opening signal for the main water supply valve 10B. ing.

The operation of the above embodiment of the present invention will be explained.

In the present invention, all the gross detectors are not triplexed, but other process detectors that generate a slightly duplicated detector signal and an equivalent process signal are used. Can be used during constant load operation where each process quantity does not vary much. Other valid detector signals for each process quantity of feedwater flow rate and steam flow rate are as follows.

(i) Water supply flow rate...During constant load operation, the water supply flow rate and steam flow rate are controlled to be balanced by I/'i three-element control. Also, the water supply flow meter used for control signals has malfunctioned. Since the influence on the steam flow rate of the same loop is small even if the steam flow rate signal of the same loop is used.

(2) Steam flow rate: If the steam flow rate needle used for the control signal fails, the water supply flow rate will change relatively quickly in the same direction as the failure direction of the steam flow meter due to the effect of three-element control. Therefore, the steam flow rate signals of other loops that are approximately the same during constant load operation are used.

Note that since there is no other equivalent process signal for the steam generator water level, the steam generator water level needle is tripled.

With the detector configuration described above, the normal signal selected by the automatic signal selector 104 is sent to the control device 101 using the three im numbers of the feed water flow meter 101 & +101b and the steam flow meter 1028 in the same loop as the feed water flow rate signal. A steam flow meter 102h, 1 is used as a water supply flow rate signal and a steam flow rate signal.
The normal steam flow rate signal selected by the signal automatic selector 105 by using the three signals of the steam flow rate needles of 02b and other loops, and the steam generator water level gauge 1 as the steam generator water level signal.
A normal steam generator water level signal selected by the automatic signal selector 106 is derived using the signals 3' of 03m, 103b, and 103c, and a control signal is generated based on these normal process signals to control the main water valve. Adjust.

Next, the signal selection method of the automatic signal selector will be explained with reference to FIG. 3, taking the water supply flow rate signal as an example.

The basic concept of the selection logic shown in FIG. 3 is as follows.

(1) Check whether the deviation between the outputs of the two water supply flow rate detectors (A1.2) is within the allowable value.

(2) If the deviation exceeds the allowable value, it is assumed that one of them is faulty.

(3) In order to determine which detector is malfunctioning, the output signal of the steam flow rate detector in the same loop is used as the reference signal.

(4) Signals close to the reference signal are considered normal, and signals far from the reference signal are considered faulty.

(5) If the currently selected signal is determined to be faulty, a switching signal is generated.

The explanation of the symbols in FIG. 3 is as follows (J=1.
2) S4. = Value of water supply flow rate detector created blade damage number (j = 1.2)
S, R = steam flow rate detector output signal (reference value) tl, g
2...Values determined from the amount of process variation and detection error, respectively. The part surrounded by a square shape is a judgment condition, and the part surrounded by a rectangle is a calculation formula.

According to the present invention, a normal detector signal can be automatically selected with the minimum equipment scale, and plant operation can be reliably continued without putting a burden on operators, thereby significantly improving the operating rate. It is possible to achieve excellent effects such as:

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a conventional example, FIG. 2 is a block diagram showing the configuration of an embodiment of the present invention, and FIG. 3 shows the detector failure diagnosis logic in the embodiment shown in FIG. It is a diagram. 111h, 101b, 201m, 201b - Water supply flowmeter, 102m+102b*202*, 202b - Steam flowmeter, 103a+103b, 103c, 203m+
203b. 203C...Steam generator water level needle, 104,105,1
06,204゜205.206...Signal automatic selector, 101.207...Control device, 109,209...
・Steam generator. Applicant's sub-agent, patent attorney Takehiko Suzue. Figure 1 M2 figure

Claims (1)

[Claims] In a ground water supply flow rate control device having a plurality of heating medium circulation loops connected to the same heat supply source and steam generators each provided separately in each loop and having a water supply pipe and a steam outlet pipe, at least two feed water flow rate detectors connected to a first automatic selection device; and at least three water level detectors for each steam generator connected to a second automatic selection device; , at least two steam flow meters provided for each of the steam generators and connected to a third automatic selection device; and a water supply control valve for each of the steam generators connected to each of the automatic selection devices. A water supply flow rate control device comprising: a control device for controlling the flow rate; and means for connecting the third automatic selection device to one of the other loose steam flow rate needles to receive the output thereof.