JPS63241389A - Monitor for state of plant - 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 [Purpose of the Invention (Industrial Field of Application) The present invention relates to a plant condition monitoring device for monitoring the operating condition of a plant including a steam generator such as a nuclear power plant.

(Prior Art) Steam is generally used as a driving fluid for power generation turbines in nuclear power plants and the like. In a plant that uses a fast breeder reactor as a heat source for the steam, high-temperature liquid sodium is introduced into the primary side of the steam generator 1 through the secondary sodium system piping 2, as shown in Figure 3. By introducing water through the water supply pipe 3 to the side, steam is generated by the heat of liquid sodium.

The steam generated in the steam generator 1 in this manner is sent to the turbine 5 through the steam pipe 4, drives the turbine 5, and is then condensed in the condenser 6. Then, the steam condensed in the water covering device 6 becomes condensed water, and after being preheated in the feed water heater 7,
The water is introduced into the secondary side of the steam generator 1 again through the water supply pipe 3 by the water supply pump 8 . In addition, the liquid sodium flowing out from the steam generator 1 was introduced into the secondary side of an intermediate heat exchanger (not shown) by the sodium pump 9, and exchanged heat with the high-temperature liquid sodium flowing on the primary side of the intermediate heat exchanger. After that, connect the primary side secondary sodium system piping 2 of the steam generator 1 again.
will be introduced in

By the way, in such a plant, the feed water flow rate or the density wave pattern varies depending on the operating conditions, which vary depending on the operating parameters such as the feed water flow rate of the steam generator 1, the primary side inlet temperature, the steam pressure, and the flow rate ratio between the feed water flow rate and the liquid sodium meteor. may generate vibrations. If such an unstable phenomenon occurs, it may have an adverse effect on the heat transfer tubes in the steam generator 1 through which high-temperature liquid sodium flows, and the health of the plant may be impaired. In this case, it has been found that vibrations in the feed water in occur as a result of the pressure difference between the secondary side inlet pressure and the secondary side outlet pressure of the steam generator 1, that is, an increase in the amount of pressure loss. As shown in the figure, a differential pressure gauge 10 is installed between the water supply piping 3 and the steam piping 4 to measure the secondary side pressure loss of the steam generator 1, and the measured value corresponds to the stability limit pressure root base curve A shown in Figure 4. The plant is operated by changing each operating parameter so as not to exceed the limit.

Note that FIG. 4 is a curve diagram showing the relationship between the amount of pressure loss on the secondary side of the steam generator and the flow rate of feed water, and shows that the flow rate of feed water increases as the amount of pressure loss increases.

(Problem to be solved by the invention) However, as mentioned above, the plant operating parameters include the feed water flow rate, primary side inlet temperature, steam pressure, primary side and secondary side.
There is a flow rate ratio with the next side, etc., and the current situation is that the operator's experience is the key to determining the stability of each operating parameter and what kind of operating state will result when changing which operating parameter and how much. It is. For this reason, in the past, all plant operations were based on the operator's experience, which increased the burden on the operator and could potentially damage the health of the plant due to operator errors in judgment. .

As mentioned above, in the past, predicting the stability of each plant operating parameter relied on the operator's experience, which resulted in an increased burden on the operator and also resulted in damage to the health of the plant due to operator errors in judgment. there is a possibility.

The present invention was made based on these circumstances, and its purpose is to improve the stable state of a plant having a steam generator.
It is an object of the present invention to provide a plant status monitoring device that improves the operational reliability and operability of a plant by monitoring with 7 displays.

[Structure of the Invention] (Means for Solving the Problems) The plant condition monitoring device of the present invention includes a high temperature fluid flow rate detector that detects the flow rate of high temperature fluid flowing through the primary side of a steam generator, and a high temperature fluid flow rate detector that detects the flow rate of high temperature fluid flowing through the primary side of a steam generator. a feed water flow rate detector that detects the feed water flow rate introduced into the secondary side of the generator; a steam pressure detector that detects the steam pressure derived from the secondary side of the steam generator; A differential pressure detector that detects the pressure difference between the next side inlet pressure and the second side outlet pressure, and the logarithm of the pressure drop on the secondary side of the steam generator and the logarithm of the feed water flow rate based on the detection signals from each of these detectors. The present invention is characterized by displaying a graph representing the above on the CRT, and displaying a straight line indicating the stable limit pressure base and the current plant status on the graph.

(Function) The plant condition monitoring device according to the present invention monitors the stable condition of the steam generator using the CR7 display based on the relationship between the water side pressure loss of the steam generator and the feed water flow rate.

By checking this CR7 display, it is possible to improve the operational reliability and operability of the plant.

(Example) An example of a plant condition monitoring device according to the present invention will be described with reference to FIG.

Reference numeral 1 in FIG. 1 indicates a steam generator, and high-temperature liquid sodium that has flowed through a secondary sodium system pipe 2 flows through the primary side of the steam generator 1. Water introduced into the secondary side of the steam generator 1 through the water supply pipe 3 is vaporized by the heat of the liquid sodium, and is sent to the turbine 5 through the steam pipe 4 and the steam control valve 11, and after driving the turbine 5. It is condensed in the condenser 6. Then, the steam condensed in the condenser 6 becomes condensate, and after being preheated in the feed water preheater 7, the steam is passed through the water supply pipe 3 via the feed water flow rate adjustment valve 12 by the feed water pump 8, and is returned to the 2 of the steam generator 1. It is designed to be introduced on the next side. On the other hand, the liquid sodium flowing out from the steam generator 1 was introduced into the secondary side of an intermediate heat exchanger (not shown) by the sodium pump 9, and exchanged heat with the high-temperature liquid sodium flowing on the primary side of the intermediate heat exchanger. After, 2
The sodium is introduced into the primary side of the steam generator 1 again through the sodium system piping 2.

1 of the steam generator 1 is provided on the upstream side of the sodium pump 9.
A sodium flow rate detector 13 is provided to detect the flow rate W2 of liquid sodium flowing on the next side.

Further, a feed water flow rate detector 14 for detecting the feed water flow u W 2 introduced into the secondary side of the steam generator 1 is provided on the downstream side of the feed water flow rate adjustment valve 12 . A steam pressure detector 15 for detecting the steam pressure P derived from the secondary side of the steam generator 1 is provided on the upstream side of the steam generator 1 .

The sodium flow rate detection signal W1 outputted from the sodium flow rate detector 13, the water meteor detection signal W2 outputted from the feed water flow rate detector 14, and the steam pressure detection signal P outputted from the steam pressure detector 15 are used for plant state monitoring. device 20
is input.

In addition, the reference numeral 10 in the figure is a differential pressure detector for detecting the pressure difference ΔP between the secondary side inlet pressure and the secondary side outlet pressure of the steam generator 1, and the differential pressure detector 10 outputs the pressure difference ΔP. The secondary side pressure loss detection signal is supplied to a plant-like B monitoring device 20.

The plant condition monitoring device 20 is composed of an input section 20a, an arithmetic control section 20b, and a CRT 20c.
The detection signals of 3.14.15.16 are input to the calculation control section 20b via the input section 20a. This arithmetic control unit 20b calculates the stability of the plant based on the input signal.
is calculated, and if the calculated stability F deviates from the operation limit value ε determined from the plant operation, the CRT20
c to issue an alarm.

Next, regarding an example of the operation of a device configured in this way,
This will be explained with reference to an example displayed on the CRT 20c shown in FIG.

The safe limit pressure drop amount Δp max of the steam generator 1 is generally approximated by an exponential function of a linear function of the logarithm of the feed water flow rate W2, and ΔP nax and W2 have the following relationship.

I n△PIllaX +a HI nW2+b =O
``...'' (1) (However, a: a constant with a negative value, b = a constant.) The straight line La indicating the safe limit pressure loss based on this relationship is the secondary of the steam generator 1 displayed on the CRT 20C. Graph 30 showing the logarithm of the side pressure drop and the logarithm of the water supply flow rate
The current plant state Sa is plotted on the graph 30 from the input Δp and w2. In this case, when Sa is in the region above the straight line La, it is stable, and when it is in the region above the straight line La, it is unstable.

In other words, when the pressure drop ΔP on the secondary side of the generator 1 is equal to or less than ΔPmax, the stability of the plant is ensured, so the stability F of the plant can be defined as follows,
It can be said that the smaller the value, the better the stability of the plant.

F=In△P+a −I nW2 +b−・−・・・・
(2) Therefore, the calculation control unit 20 of the operating state monitoring device 20
In a, the secondary side pressure loss ΔP of the steam generator 1 and the feed water flow rate W2 are read, and the stability F of the plant defined by equation (2) is calculated.

Next, the calculated stability F is compared with a preset operating limit value ε, and if F deviates from ε, an alarm stability deterioration Aa is displayed on the CRT 20C.

At this time, the operation limit value ε may be a function of the feed water flow rate W2 or other plant conditions.The secondary side pressure drop ΔP of the steam generator 1 and the feed water flow Ek W 2 are generally approximated by the following relational expression. Ru.

In△P+f (P, W+ /W2 > ・I nW2
+g (P, W+ /W2) = O... (3) Here, the relationship between the logarithm of ΔP and the logarithm of W2 is expressed by a linear equation, and the coefficient is the steam pressure P and the primary side It is expressed as a function of the meteor ratio of the meteor W1 and the secondary flow rate W2. From P and W determined from the input process amount, /W2, f (
P , W+ /W2 ), and g (P, W+ /W
2), and the straight line Lb 1c based on the relationship of equation (3)
Draw on the graph 30 of RT20c.

This Lb shows the transition of the stable state when ΔP or W2 is changed by driving operation while keeping the current P and W 1/W 2 constant.

In the embodiment described above, the secondary side pressure loss ΔP of the steam generator 1
It is possible to judge the printing safety at a glance from the graph 30 on the CRT2Oc showing the relationship between the water supply flow rate W2 and the water supply flow rate W2.

Also, under constant P and W, /W2, 8P.

The stable state transition when changing W2 also shows that CRT2
This can be predicted from the graph 30 on the OC.

[Effects of the Invention] According to the present invention, the stability of the operating state of a plant can be
It is possible to provide a plant condition monitoring device that can be confirmed more reliably and significantly improve the reliability of the plant.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of a plant status monitoring device showing an embodiment of the present invention, Fig. 2 is an operating state diagram showing an example of the CRT display in Fig. 1, and Fig. 3 is a diagram of a conventional fast breeder reactor power plant. FIG. 4 is a system diagram showing the turbine system from the steam generator. FIG. 4 is a diagram showing the relationship between the secondary pressure loss of the steam generator and the feed water flow rate in FIG. 3. 1...Steam generator 13...Sodium flow rate detector 14...
......Water supply flow rate detector 15...
Steam pressure detector 16...Differential pressure detector 20...Plant condition monitoring device 20a.
... Input section 20b ... Arithmetic control section 20C ... CRT Agent Patent attorney Rule Chika Ken Yutong Wang Hou Hongwen jb Fig. 1 Fig. 2 謔水龜i Fig. 4

Claims (1)

[Claims] (1) a high-temperature fluid flow rate detector that detects the flow rate of high-temperature fluid flowing through the primary side of the steam generator; and a water supply flow rate detector that detects the flow rate of feed water introduced into the secondary side of the steam generator;
a steam pressure detector that detects the steam pressure derived from the secondary side of the steam generator; and a differential pressure detector that detects the pressure difference between the secondary side inlet pressure and the secondary side outlet pressure of the steam generator. and,
A plant condition monitoring device characterized by comprising means for displaying a stable condition of the plant on a CRT based on detection signals from each of these detectors.