JPS5817397A - Fast breeder power 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 The present invention relates to a fast breeder reactor power plant, particularly a fast breeder reactor power plant having primary and secondary coolant loops.

A fast breeder reactor that uses liquid metal as a coolant, has a nuclear reactor, an intermediate heat exchanger, a 0fllK primary coolant loop, and a secondary coolant loop between the intermediate heat exchanger and the steam generator. In a power plant, the plant output (electrical output) is affected by fluctuations in the main steam conditions, so rounding is done to avoid this, and the main steam conditions are controlled to be constant pressure and temperature.

Therefore, the steam temperature at the outlet of the steam generator is constant regardless of the plant output, and the secondary coolant loop,
As shown in FIG. 1, the temperature of the liquid metal (e.g., 9 um) at the reactor outlet, which is linked via the primary coolant loop, remains approximately constant regardless of the plant output. The horizontal axis of this figure,
The vertical axis shows plant output (electricity output) and temperature, respectively, with 1 indicating the sodium temperature at the reactor outlet and 2 indicating the steam temperature at the steam generator outlet.

K, which performs such control to keep the reactor outlet sodium temperature constant with respect to the plant output, adjusts the coolant flow rate of each of the primary and secondary systems to the reactor thermal output. needs to be controlled proportionally. On the other hand, since the reactor thermal output and the plant output are approximately proportional, the primary system and secondary system coolant flow rates are expressed as shown in Figure 3, at the plant outlet KP.
1 means proportional control. The horizontal and vertical axes of this figure show the plant output (modifications to the rated value), respectively.

The flow rate (value relative to the rated value) is taken, and 3.4 indicates the primary system coolant flow rate and the secondary system coolant flow rate, respectively.

Figure 3 shows such a plant that uses liquid metal as a coolant, has primary and secondary coolant loops, and has a plant output KFtf.
FIG. 2 is a system diagram of a conventional coolant flow rate control system for a fast breeder reactor power plant that performs flow rate control in proportion to f. In this figure, %11 is the reactor, 12 is the intermediate heat exchanger, 1B is the primary coolant loop, 14 is the main circulation system, and 1B is 1
Secondary pump drive AC motor, 16 is primary system flow rate needle, 17
#i Primary system flow rate signal, 18 is primary system flow rate program signal, 19 is primary system flow rate control/% 110 is primary system frequency command signal, 111 is primary system variable frequency power supply, 112 is primary system variable frequency The power is shown, 121 is the superheater', 22
is an evaporator, 23 is a secondary system coolant loop, 24 is a secondary system main circulation pump, 26 is a secondary system pump driving AC motor, 26
is the secondary system flow rate needle, 27 is the secondary system flow rate signal, 2B is the secondary system flow rate Goodaram signal, 29 is the secondary system flow rate controller, 21G
211 represents a secondary system frequency command signal, 211 represents a secondary system variable frequency power source, and 211 represents a primary system variable frequency power source.

The flow rate of the coolant in the primary system cooling loop 13 that circulates between the reactor 11 and the intermediate heat exchanger 1112 is measured by the primary system flow meter 16, converted to a primary system flow rate signal 17, and transmitted to the primary system. The flow rate program signal 18 is input to the primary system flow rate controller 19 . The primary system flow rate controller 19q, the primary system flow rate program signal 18, the primary system flow rate signal 17, and K, which have a relationship as shown in straight line 3 in FIG. A primary system frequency command signal 110 that matches the control request is input to a primary system variable frequency power supply 111. The primary system variable frequency power supply 111 receives the primary system frequency command signal 11G, generates the primary system variable frequency power 112, and supplies it to the primary system pump drive AC motor 15. The primary system pump driving AC motor 15 is connected to the primary system main circulation pump 14, and is controlled by the primary system variable frequency power 112, and the primary system refrigerant flow rate control characteristic matches the primary system refrigerant flow rate control characteristics. Get the flow rate.

The flow rate of the coolant in the secondary coolant loop 23 that circulates between the intermediate heat exchanger 12, the superheater 21, and the evaporator 22 is controlled in exactly the same way as the flow rate control of the coolant in the primary coolant loop. be exposed.

In this way, in a conventional fast breeder reactor power generation platform, the control of the coolant flow rates in the primary and secondary systems is rounded, and a total of two units are used, one each for the primary and secondary coolant loops. Since variable frequency power supplies are installed, there is room for improvement from an operational and maintenance standpoint and from an economic standpoint. In such a case, it would not work as a heat transport system for a fast breeder reactor power plant*, so there would be little necessity to install two units.

The present invention eliminates these problems, and from the viewpoints of operation and maintainability, economy, and reliability, it is possible to improve the speed by controlling the coolant flow rate. This system enables the provision of a breeder reactor power plant, and has nine coolant circulation pumps installed between the nuclear reactor and the intermediate heat exchanger, and between the intermediate heat exchanger and the steam generator. The AC motor that drives the secondary coolant loop, the secondary coolant loop, and the coolant circulation pump is controlled so that the coolant flow rate of the primary and secondary coolant loops changes according to their respective flow control characteristics. In the fast breeder reactor power plant, the coolant flow rate control means controls the AC motor that drives the coolant circulation pump to the primary and secondary cooling loops. The high frequency power supply device operates according to the flow control characteristics of the coolant loop of one of the systems, and the difference between the primary system flow control characteristics and the secondary system flow control characteristics is determined, and based on that #, It is characterized by comprising a control device that causes an AC motor that drives a coolant circulation pump of a coolant loop of another system in the secondary system to match the flow rate control characteristics of the other system.

In the present invention, the primary system flow control characteristics and the secondary system flow control characteristics with respect to the plant output are such that even if the plant output KsI is low in the primary system, securing a large flow rate is a safety concern for the reactor. In the secondary system, even at a low i plant output, the temperature difference between the steam generator inlet and outlet becomes large. This variable frequency power supply was designed with the focus on its ability to serve as a power source for the pump-driving AC motors of the primary and secondary coolant loops, and is a comprehensive heat transport system for fast water enrichment reactor power plants. It is possible to improve the operational maintainability, economy, and reliability of the system.

Examples will be described below.

FIG. 4 is a system diagram of a coolant flow rate control system O for a fast breeder reactor power plant according to one embodiment. In this figure, the same parts as in FIG.
Reference numeral 2 indicates a variable frequency power, 33 a correction calculator, 34 a line flow rate correction signal, 35 an AC motor attached control device, and 36 an AC motor correction control signal.

In this embodiment, the variable frequency power supply device 31 serves as a shared power source for the primary system pump drive AC motor 1B and the secondary system pump drive AC motor 2s, and its frequency control is made to match the primary system flow rate control characteristics. This control line is exactly the same as in the conventional case, and the flow rate of the primary system coolant loop matches the primary system flow rate control characteristic. On the other hand, in the secondary coolant loop, the 91st system flow rate signal 17 and the secondary system flow rate signal 27 are obtained by the primary system flowmeter 16 and the secondary system flowmeter 26, respectively.
and a computation unit 33 that corrects the secondary system flow rate tool ram signal 28.
is input, the difference between the primary system flow rate control characteristic and the secondary system flow rate control characteristic is corrected, and a flow rate correction signal 34 matching the secondary system flow rate control characteristic is output. The AC motor accessory control device 35 receives the flow correction signal 34 and provides an AC motor correction control signal 36 to the secondary pump drive AC motor 24 .

Therefore, although the frequency characteristic of the variable frequency power supply device 310 is a primary system flow rate control characteristic, the coolant flow rate of the secondary system coolant loop 23 is rounded and corrected by the AC motor attached control device 35, and the coolant flow rate of the secondary system coolant loop 23 is a secondary system flow rate control characteristic. Matches the system flow control characteristics. FIG. S shows a specific example of FIG. 4, and the same parts as in FIG. 4 are given the same reference numerals. In this specific example, there are 4 electric motors in the variable frequency power supply! A fluid coupling variable frequency power supply device 44 consisting of a fluid coupling 42 and an alternating current generator 43 is used, a fluid coupling scoop pipe drive device 45 is used as a flow rate controller, and a secondary pump driving AC electric I! As a control device attached to 25, an alternating motor secondary resistance control device 46 is used.

In this way, the large-capacity variable frequency power supply device of Jin's embodiment can use a fluid coupling variable frequency power supply device that has already been put into practical use for light water-cooled nuclear reactor power plants. 2 attached to the secondary pump drive AC motor
Since it is possible in the range of 7G-Zoo% of the rotation speed control box of the resistance control device, it is applicable to fast breeder reactor power plants.

In this way, in the fast breeder reactor power plant of the example, the variable frequency power supply device, which was conventionally installed in each coolant loop of the primary system and the secondary system, is shared. Self-operation maintainability is improved by reducing maintenance.

(9) By sharing the variable frequency power source, the total cost of the flow control system can be reduced and performance performance can be improved. This creates more space for variable frequency power supply. As a comprehensive heat transport system, reliability is improved and efficient operation is achieved.

In addition, in the example, the case where the frequency control of the variable frequency power supply device is made to match the flow rate control characteristics of the primary system will be explained. Flow rate control is performed by calculating the difference between the primary system flow rate control characteristics and the secondary system flow rate control characteristics using a correction calculator, and using this flow rate correction signal, a control device attached to the primary system pump drive AC motor is operated. , may be made to match the primary system flow rate control characteristics, and in this case also works in the same manner as in the above case,
You can get the same effect.

As described above, the fast breeder reactor power plant of the present invention can control the coolant flow rate with improved reliability in terms of operation and maintenance, economy, and industrial efficiency. The effect is great.

[Brief explanation of drawings]

Figure 1 is a diagram showing the relationship between plant output (electrical output), reactor output sodium temperature f, and steam generator outlet steam temperature in a fast breeder reactor power plant, and Figure 2 is a diagram showing the relationship between plant output and 1 A diagram showing the relationship between the secondary system cooling reed flow rate and the secondary system coolant flow rate. Fig. 3 is a system diagram of the coolant flow control system of a conventional fast breeder reactor power plant. Fig. 4 is a diagram showing the relationship between the secondary system coolant flow rate and the secondary system coolant flow rate. The system diagram of the coolant flow control system of one embodiment of a fast breeder reactor power plant, Figure 5, is also 1!
It is a system diagram showing a specific example of the department. 11... Nuclear reactor, 12... Intermediate heat exchanger, 13...
Primary system coolant loop, 14-... Primary system main pump,
15--Primary system pump driving AC motor, 16--Primary system flow meter, 19--Flow rate controller, 22--Evaporator, 2
3...Secondary system coolant loop, 24...Secondary system main circulation pump, 21-Secondary system pump drive AC motor, 26...
・Secondary system flowmeter, 31...Variable frequency power supply, 33...
・Correction calculator, 35...AC motor attached control device')F
1 Figure 7 ° phosphorus/-, ttt etc. lt Ka Figure 2 γ Run Li: Force (tsr fJ/[) calculation δ
figure

Claims (1)

[Claims] L A primary coolant loop having a coolant circulation pump, which is provided between the nuclear reactor and the intermediate heat exchanger, and between the intermediate heat exchanger and the steam generator, and 2
means for controlling an AC motor that drives a secondary coolant loop and the coolant circulation pump so that the coolant flow rate of the primary coolant loop and the secondary coolant loop varies according to their respective flow rate control characteristics; fast breeder reactor power generation plan)
k-The coolant flow rate control means controls the AC motor that drives the coolant circulation pump of the primary system and secondary system coolant loop to one of the primary system and secondary system. The high frequency power supply device operates according to the flow control characteristics of the OSO coolant loop, and the difference between the primary system flow control characteristics and the secondary system flow control characteristics is determined, and based on the IIK, the difference between the primary system and secondary system flow control characteristics is determined. Connect the AC motor that drives the coolant circulation pump of the coolant loop of the other system to the flow rate side of the other system.
A fast breeder reactor observation plant characterized by a control device for matching characteristics.