JPH0733891B2 - Plant warming controller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a superheater for superheating steam generated in a steam generator in a fast breeder reactor power plant or the like, and an inlet pipe and an outlet of the superheater. The present invention relates to a warming control device for a plant that warms pipes and the like.

(Prior Art) A fast breeder reactor power plant generally has a reactor that uses liquid sodium as a coolant, and a primary cooling system that transfers the heat energy generated in the reactor to an intermediate heat exchanger through the primary coolant. And a secondary cooling system that transfers the secondary coolant that has undergone heat exchange with the primary heat exchanger in the intermediate heat exchanger to the steam generator, and water that transfers the steam generated in the steam generator to the power generation turbine.
It is composed of a steam system.

The water / steam system in such a fast breeder reactor power plant is designed so that the steam generated in the steam generator is superheated by the superheater and then sent to the power generation turbine, and the steam from the steam generator is superheated. If it is suddenly introduced into the superheater, excessive thermal stress is generated in the superheater and its inlet and outlet pipes. Therefore, conventionally, the superheater is warmed at the time of starting the plant to reduce the thermal stress. For this warming, the low temperature steam of the auxiliary boiler is usually used, and the operator monitors the inlet temperature and outlet temperature of the superheater and the temperature rise rate, etc., and operates the warming adjustment valve to control the amount of low temperature steam to the superheater. Is being adjusted.

However, such warming operation not only requires the experience of skilled operators, but also increases the number of operators and the burden on the operators. There was a possibility that excessive thermal stress would be applied to the outlet piping and the integrity of the plant.

(Problems to be Solved by the Invention) As described above, conventionally, the operator operates the valve opening of the superheater warming adjustment valve while monitoring the inlet temperature and the outlet temperature of the superheater, the temperature increase rate, and the like. Therefore, a skilled operator's experience is required, which further increases the number of operators and the burden on the operators. In addition, the operator's operation error may cause excessive thermal stress on the superheater and its inlet pipe and outlet pipe, which may impair the soundness of the plant.

The present invention has been made based on such circumstances,
The purpose is to be able to perform warming of the superheater and its inlet pipe and outlet pipe automatically without operator's hand, which can reduce the number of operators and the burden, and the reliability of the plant. It is an object of the present invention to provide a warming control device for a plant, which can be improved.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention provides a superheater inlet temperature detector for detecting the inlet temperature of a superheater for superheating steam, and Superheater outlet temperature detector for detecting the outlet temperature, warming auxiliary steam pipe for supplying auxiliary steam for warming to the superheater, auxiliary steam flow for warming provided in this auxiliary steam pipe for warming Adjusting valve, the superheater inlet temperature detected by the superheater inlet temperature detector and the superheater outlet temperature detected by the superheater outlet temperature detector are respectively compared with the set value, and the higher deviation value is set. The temperature deviation signal is used as a temperature deviation signal, the rate of change of the superheater inlet temperature and the superheater outlet temperature are respectively compared with set values, and the value with the smaller deviation is used as the temperature change rate deviation integral signal, and the temperature deviation signal and the temperature change It compares the deviation integral signal is obtained by including a low rather a valve opening control unit which controls a signal proportional integral to the valve opening degree of the warming auxiliary steam flow rate adjustment valve for its value.

(Operation) The warming control device according to the present invention detects the inlet temperature and the outlet temperature of the superheater by the temperature detectors respectively, compares the signals from these temperature detectors with a predetermined set value, and deviates them. The higher value of is used as the temperature deviation signal, the temperature change rates of the inlet temperature and the outlet temperature of the superheater are compared with the set values, respectively, and the lower value is used as the temperature change rate deviation integrated signal. The deviation signal and the temperature change rate deviation integration signal are compared with each other, and a signal having a low value is proportionally integrated to obtain a valve opening control signal of the auxiliary steam flow rate adjusting valve for warming.

(Example) Hereinafter, one example of the present invention will be described with reference to the drawings.

FIG. 1 shows an embodiment of the present invention and shows the configuration of a warming control device in a fast breeder reactor power plant. In the figure, reference numeral 1 is a water supply pipe for supplying water to the steam generator 2, and the water supply supplied from the water supply pipe 1 is vaporized by the steam generator 2. Then, the feed water vaporized by the steam generator 2 is introduced into the superheater 4 through the superheater inlet pipe 3, becomes superheated steam in the superheater 4, and becomes the superheater outlet pipe 5
And is sent to a power generation turbine (not shown). Liquid sodium piping 6 of the secondary cooling system is connected to the heating sides of the steam generator 2 and the superheater 3, respectively.

A warming auxiliary steam pipe 7 is connected to the superheater inlet pipe 3. The warming auxiliary steam pipe 7 is provided with a warming auxiliary steam flow rate adjusting valve 8, and the flow rate adjusting valve 8 adjusts the flow rate of the warming auxiliary steam. The auxiliary steam for warming is supplied from an auxiliary boiler (not shown), and its temperature is about 200 ° C. Also, the superheater inlet pipe 3
Further, temperature detectors 9 and 10 are provided in the superheater outlet pipe 5, respectively. Signal T from these temperature detectors 9, 10
1, T2 are input to the valve opening control device 11, and the valve opening control of the auxiliary steam flow rate adjusting valve 8 for warming is performed by a control signal output from the valve opening control device 11. There is.

FIG. 2 shows the configuration of the valve opening control device 11. Signals T1 and T2 from the temperature detectors 9 and 10 are the same as those of the valve opening control device 1.
The comparators 12 and 13 of 1 are respectively compared with the inlet temperature set value S1 and the outlet temperature set value S2. Then, the higher value selection circuit 14 selects the value with the higher deviation as the temperature deviation signal S.

Further, the signals T1 and T2 from the temperature detectors 9 and 10 are respectively converted into temperature change rates by the differentiating circuits 15 and 16 of the valve opening control device 11, and then the inlet temperature change rates are respectively changed by the comparators 17 and 18. After being compared with the set value L1 and the outlet temperature change rate set value L2, and further integrated by the integrating circuits 19 and 20, the lower value selecting circuit 21 selects the lower integrated value as the temperature change rate deviation integrated signal L. To be done. The temperature deviation signal S output from the high value selection circuit 14 and the temperature change rate deviation integration signal L output from the low value selection circuit 21 are input to the proportional integration circuit 23 via the low value selection circuit 22, The output signal of the proportional-plus-integral circuit 23 is supplied to the warming auxiliary steam flow rate adjusting valve 8.

In such a configuration, the superheater 4 and its inlet pipe 3
For the warming of the outlet pipe 5, the auxiliary steam for warming is introduced from the auxiliary steam pipe 7 for warming, and warming is performed in the order of the inlet pipe 3, the superheater 4, and the outlet pipe 5. When steam is rapidly introduced, thermal stress may occur in the superheater 4 and the inlet pipe 3 to the outlet pipe 5, so it is necessary to perform warming at a certain temperature change rate. Here, at the start of warming, the signals T1 and T2 from the temperature detectors 9 and 10 are
Is close to room temperature, whereas the superheater inlet temperature set value S1 and the superheater outlet temperature set value S2 are high temperature settings matched with the operation of the superheater 4. Therefore, at the start of warming, the temperature deviation signal S output from the high value selection circuit 14 has a large positive value, and as a result, the proportional integration circuit 23 operates the auxiliary steam flow rate adjusting valve 8 for warming to "open". The control signal is output.

In this way, when the warming auxiliary steam flow rate adjusting valve 8 is opened and the warming auxiliary steam is introduced from the warming auxiliary steam pipe 7 to the superheater inlet pipe 3, the inlet temperature detection signal T1 or the outlet detection signal is detected. The temperature signal T2 sharply rises beyond the inlet temperature change rate set value L1 or the outlet temperature change rate set value L2. At this time, the temperature change rate deviation integrated signal L output from the low value selection circuit 21 has a negative value, and the proportional integration circuit 23 outputs a control signal for operating the warming auxiliary steam flow rate adjusting valve 8 to "open". To be done. At this time, the latter is selected as a low value between the positive temperature deviation signal S and the temperature change rate deviation integrated signal L near zero, so that the inlet temperature and the outlet temperature of the superheater 4 are set to the inlet temperature change rate set value L1 and The temperature is raised within a range that does not exceed the outlet temperature change rate set value L2.

Next, when the warming is sufficiently performed and the superheater inlet temperature T1 detected by the temperature detector 9 approaches the inlet temperature set value S1, the high value selection circuit 14 causes the temperature deviation signal from the comparator 13, that is, the superheater outlet. Select the deviation between the temperature T2 and the outlet temperature set value S2. At this time, since the temperature rise rates of the inlet temperature T1 and the outlet temperature T2 are close to zero, the low value selection circuit 21
The signal output from is higher than the signal output from the high value selection circuit 14.

Therefore, when the superheater inlet temperature T1 approaches the inlet temperature set value S1, the low value selection circuit 22 should select the signal from the high value selection circuit 14 (deviation between the superheater outlet temperature T2 and the outlet temperature set value S2). Therefore, it is possible to raise the inlet temperature and the outlet temperature of the superheater 4 to the set temperatures almost at the same time while keeping the temperature rise rate below the limit value at which thermal stress does not occur.

[Effects of the Invention] As described above, the present invention includes a superheater inlet temperature detector that detects an inlet temperature of a superheater that superheats steam, and a superheater outlet temperature detector that detects an outlet temperature of the superheater. The warming auxiliary steam pipe for supplying the warming auxiliary steam to the superheater, the warming auxiliary steam flow rate adjusting valve provided in the warming auxiliary steam pipe, and the superheater inlet temperature detector The detected superheater inlet temperature and the superheater outlet temperature are compared with the set values detected by the superheater outlet temperature, and the higher deviation value is used as the temperature deviation signal. The rate of change of the outlet temperature is compared with the set value, and the value with the smaller deviation is used as the temperature change rate deviation integrated signal, and the temperature deviation signal and the temperature change rate deviation integrated signal are compared to obtain the lower value. Since it is equipped with a valve opening control device for controlling the valve opening of the warming auxiliary steam flow rate adjusting valve by proportionally integrating the signal of the above, when warming the superheater and its inlet pipe and outlet pipe, It is possible to raise the inlet temperature and the outlet temperature of the superheater to the set temperature almost at the same time while keeping the temperature rise rate below the limit value at which thermal stress does not occur.

[Brief description of drawings]

1 and 2 show an embodiment of the present invention. FIG. 1 is a block diagram of a warming controller, and FIG. 2 is a block diagram of a valve opening controller. 1 ... Water supply pipe, 2 ... Steam generator, 3 ... Superheater inlet pipe, 4 ... Superheater, 5 ... Superheater outlet pipe, 6 ... Liquid sodium pipe, 7 ... Auxiliary steam for warming Piping, 8 ... Auxiliary steam flow control valve for warming, 9 ...
Superheater inlet temperature detector, 10 ... Superheater outlet temperature detector,
11 …… Valve opening control device.

Claims (1)

[Claims] 1. A superheater inlet temperature detector for detecting an inlet temperature of a superheater for superheating steam, a superheater outlet temperature detector for detecting an outlet temperature of the superheater, and a warming auxiliary for the superheater. Auxiliary steam piping for warming that supplies steam, an auxiliary steam flow rate adjusting valve for warming provided in this auxiliary steam piping for warming, the superheater inlet temperature detected by the superheater inlet temperature detector, and the above The superheater outlet temperature detected by the superheater outlet temperature detector is compared with the set value, and the higher deviation value is used as the temperature deviation signal, and the change rates of the superheater inlet temperature and the superheater outlet temperature are set respectively. The value having the smaller deviation from the value is used as the temperature change rate deviation integrated signal, the temperature deviation signal and the temperature change rate deviation integrated signal are compared, and the signal having the lower value is proportionally integrated to obtain the w A warming control device for a plant, comprising: a valve opening control device for controlling a valve opening of an auxiliary steam flow rate adjusting valve for warming.