CN202205469U

CN202205469U - System for detecting rod position of nuclear power plant

Info

Publication number: CN202205469U
Application number: CN2011203002301U
Authority: CN
Inventors: 刘爱青; 唐崟; 张斌; 王冠峰; 华明俊
Original assignee: State Nuclear Power Automation System Engineering Co Ltd
Current assignee: State Nuclear Power Automation System Engineering Co Ltd
Priority date: 2011-08-18
Filing date: 2011-08-18
Publication date: 2012-04-25
Anticipated expiration: 2021-08-18

Abstract

The utility model discloses a system for detecting a rod position of a nuclear power plant, which comprises a position detecting device and a control rod group located in a pressure container; the position detecting device is installed on the outer surface of a stroke cover; the position detecting device is connected with the control rod group by a control rod driving mechanism, wherein the position detecting device comprises a plurality of continuous control units; each control unit comprises sensor coils and rod dropping test coils; the plurality of sensor coils are driven by one transformer T1; and the rod dropping testing coils of each control unit are connected from the head to tail to form two leading ends for testing induced voltage. The system for detecting a rod position of a nuclear power plant provided by the utility model is provided with rod dropping test coils. The rod dropping time curve can be acquired by the voltage induced from the rod dropping test coils in the rapid dropping process of control rod. Therefore, the free rod dropping time can be tested conveniently and the test reliability is further improved.

Description

Nuclear power station rod position detecting system

Technical field

The utility model relates to a kind of control rod detection system, relates in particular to a kind of nuclear power station rod position detecting system.

Background technology

The excellent position detecting system of nuclear power station utilizes the control rod positional detecting device, uses coil-induced principle, demonstrates the position of control rod at reactor core.When outage, the control rod assembly falls into reactor core fast by deadweight, the shutdown of realization response heap, and rely on the voltage that in control rod positional detecting device coil, induces in the control rod landing process fast this moment, obtains the rod drop time curve.

In the nuclear reactor of pressurized-water reactor nuclear power plant; The control rod assembly is in the pressure vessel of HTHP, the position reaction of control rod in reactor core the operating mode of reactor, but its position can only be measured indirectly; The control rod position detecting device is mounted in the outside of control rod stroke case (pressure-containing member); Utilize the principle of electromagnetic induction, convert the mechanical shift of control rod to electric signal and handle, be used to keep watch on the physical location of control rod at reactor core; In the emergency shut-down operating mode, the control rod assembly falls into reactor core fast by deadweight, and the shutdown of realization response heap utilizes the induced voltage signal in the coil to keep watch on the control rod rod drop time this moment, realizes the detection to shutdown condition.See also Fig. 1; Nuclear power station rod position detecting system comprises positional detecting device 1 and the control rod group of being located in the pressure vessel 43; Said positional detecting device 1 is installed in the outside of stroke case 7; Said positional detecting device 1 links to each other with CRDM 2, and said CRDM comprises hook parts, magnetic inversion line coil assembly, pressure-containing member and drive-rod part, and said drive-rod part links to each other with control rod group 3.

The control rod position detecting device of reactor is a principle of utilizing electromagnetic induction, measures the physical location of control rod at reactor core.U.S.'s Westinghouse Electrical Corp. is 98805005.6 at application number; The utility model name is called the apparatus and method of having described command bundle rods for nuclear reactors free-fall time in " measuring the command bundle rods for nuclear reactors apparatus and method of free-fall time "; As shown in Figure 2, used a plurality of cell windings 32 that are provided with along the series connection of control rod transmission housing, the laminate patch of cell winding 32 is divided into two group A that sandwich each other and group B; Link to each other with the scrambler 34 of group A, the scrambler 36 of group B respectively; Each cell winding 32 has two exits, and one of them exit connects together and links to each other with common wire 42, like the A1 among Fig. 3 ... A24.The other end of each coil connects together after the Lo of transformer T1 one side is passed three resistance R 1, R2 and R3, and R1 is a coil resistance, and R2 is the resistance from coil to excellent position indication electronic housing cable, and R3 is the output impedance of encoder plate.The sensor that a plurality of cell windings are formed is supplied power by single transformer T1.In excellent drop test, the short circuit of transformer T1 primary coils.The testing procedure of its control rod free-fall time comprises: break off the transformer main from power supply; Make transformer T1 short circuit; And the voltage that in impedance on the common transmission line, forms during through a plurality of cell winding when measuring control rod and falling, impedance is shown in R4 among Fig. 3 on the common transmission line.The test of this control rod free-fall insertion time is with the primary short of transformer when needing a relay that power supply is cut off; Relay contact 52 like short circuit transformer T1 main; With the secondary short circuited of transformer, obtain the rod drop time curve through the variation that detects the voltage on the common transmission cable 42 then simultaneously, and resistance R on the common wire 42 4 is very little and the consistance of a plurality of clusters of very difficult assurance; The rod test that falls of emergency shut-down during the very difficult realization response stack operation; Therefore, be necessary further to improve nuclear power station rod position detecting system, make test convenient reliable.

Summary of the invention

The utility model technical matters to be solved provides a kind of nuclear power station rod position detecting system; The free-fall insertion time when being more convenient for measuring the control rod free-falling; And fall the simultaneously free-fall insertion time test of rod of a plurality of clusters that emergency shut-down causes in the energy measurement reactor operation, further improve the reliability of test.

The utility model is to solve the problems of the technologies described above the technical scheme that adopts to provide a kind of nuclear power station rod position detecting system; Comprise positional detecting device and the control rod group of being located in the pressure vessel; Said positional detecting device is installed in the outside of stroke case; Said positional detecting device links to each other with CRDM, and said CRDM comprises hook parts, magnetic inversion line coil assembly, pressure-containing member and drive-rod part, and said drive-rod part links to each other with the control rod group; Wherein, Said positional detecting device comprises a plurality of successive control unit, and said control module is divided into two groups of A, B alternately, and each control module comprises cell winding and falls two kinds of coils of excellent test coil; A plurality of cell windings are supplied power by a transformer T1, the end to end exit that is formed with two test induced voltages of the excellent test coil that falls of each control module.

The utility model contrast prior art has following beneficial effect: the nuclear power station rod position detecting system that the utility model provides; Through being provided with excellent test coil; Utilize the control rod voltage of in the excellent test coil that falls, responding in the process that hurtles down to obtain the rod drop time curve; Test process does not receive the influence of supply transformer, is convenient to test the free-fall insertion time, further improves the reliability of test.

Description of drawings

Fig. 1 is a nuclear power station rod position detecting system structural representation;

Fig. 2 is magnetic test coil structural representation in the existing excellent position detecting system;

Fig. 3 is the circuit theory synoptic diagram that has the rod test now;

Fig. 4 is the existing transformer short circuit synoptic diagram during rod test that falls;

Fig. 5 is a magnetic test coil structural representation in the utility model rod position detecting system;

Fig. 6 is the excellent circuit theory synoptic diagram of testing for the utility model falls.

Among the figure:

1 positional detecting device, 2 CRDMs, 3 control rod groups

4 pressure vessels, 6 high-temperature high pressure waters, 7 stroke cases

8 cell windings 9 excellent test coil 32 coils that fall

Scrambler 42 common wires of 36 groups of B of scrambler of 34 groups of A

The relay contact of 52 short circuit transformer T1 mains.

Embodiment

Below in conjunction with accompanying drawing and embodiment the utility model is done further to describe.

Fig. 5 is a magnetic test coil structural representation in the utility model rod position detecting system.

See also Fig. 1 and Fig. 5; The utility model rod position detecting system comprises positional detecting device 1 and the control rod group of being located in the pressure vessel 43; Said positional detecting device 1 is installed in the outside of stroke case 7, and said positional detecting device 1 links to each other with CRDM 2, and said CRDM comprises hook parts, magnetic inversion line coil assembly, pressure-containing member and drive-rod part; Said drive-rod part links to each other with control rod group 3; Wherein, said positional detecting device 1 comprises a plurality of successive control unit, and said control module is divided into two groups of A, B alternately; Each control module comprises cell winding 8 and falls 9 two kinds of coils of excellent test coil; The cell winding 8 of each control module has two exits, and one of them exit connects together and links to each other with common wire 42, the excellent test coil 9 end to end exits that are formed with two test induced voltages that fall of each control module.

The cell winding 8 of the said sniffer control module of the utility model is identical with cell winding 32 shown in Figure 2; When an alternating current passes through coil; Produce exchange flux, when the control rod of ferromagnetic material passed through this coil position, the impedance of coil will change; Change in voltage that this impedance variations of digital coding circuit collection causes handle can controlled rod position signalling, detail no longer one by one at this.But can find out from Fig. 5; The positional detecting device of the utility model has increased the excellent test coil that falls; The excellent test coil that falls of each control module divides into groups to carry out end to end and forms two exits; This excellent test coil that falls is exclusively used in the test of control rod free-fall insertion time, therefore, and the free-fall insertion time when being more convenient for measuring the control rod free-falling; And fall the simultaneously free-fall insertion time test of rod of a plurality of clusters that emergency shut-down causes in the energy measurement reactor operation, further improve the reliability of test.

Please continue referring to Fig. 6, free-fall insertion time test method is following in the above-mentioned nuclear power station rod position detecting system:

A) open when test rod of falling before the heap, break off the power supply of transformer T1, control rod leans on deadweight to fall, and tests the induced voltage curve on 9 two exits of excellent test coil that fall in this process, promptly obtains the rod drop time curve;

B) run duration; Adopt the power supply of the signal controlling transformer T1 of shutdown isolating switch, when emergency shut-down occurring, the signal of said shutdown isolating switch cuts off power supply; A plurality of control clusters fall by deadweight simultaneously; Through testing the induced voltage curve on two exits of excellent test coil, obtain the rod drop time curve in this process, can gather the free-fall insertion time of a plurality of clusters simultaneously.

Can know from Fig. 4; During the test of existing control rod free-fall insertion time the 115V power supply of transformer T1 is broken off; And make main, the secondary short circuited of transformer T1, so that transformer T1 removes, record excellent test curve from public wiring 42 then from the excellent test loop that falls.And the test of the control rod free-fall insertion time of the utility model; Test excellent test curve from the excellent test coil 9 of falling of special use; Needn't consider the influence of transformer T1, because transformer T1 is original just not in this test loop, so the test of free-fall insertion time is convenient reliable.

In sum, it is very important to the safety of guaranteeing nuclear reactor accurately to record control rod group 3 free-fall insertion time when the reactor shutdown.But can know that from Fig. 1 the control rod assembly is positioned at pressure vessel 4 inside of sealing in the presurized water reactor, in the high-temperature high pressure water 6 of band radiation, it is very difficult directly testing its position.Therefore; Control rod positional detecting device 1 has adopted the principle of electromagnetic induction; Positional detecting device 1 is installed in the outside of control rod stroke case 7, and the coil that utilizes control rod group 3 to insert, pass control rod positional detecting device 1 causes that the variation of coil impedance detects the position of control rod group 3.The control rod positional detecting device 1 that the utility model provides comprises cell winding 8 and falls excellent test coil 9; Cell winding 8 wherein is used for realizing detecting the position of control rod group 3 at reactor core; And the excellent test coil 9 that falls is exclusively used in the detection of control rod free-fall insertion time; When the rod that falls detects, detect the free-fall insertion time of control rod group 3 accurately through magnetic induction voltage in the excellent test coil 9 that falls.

Though the utility model discloses as above with preferred embodiment; Right its is not in order to limit the utility model; Any those skilled in the art; In spirit that does not break away from the utility model and scope, when can doing a little modification and perfect, so the protection domain of the utility model is when being as the criterion with what claims defined.

Claims

1. nuclear power station rod position detecting system; Comprise positional detecting device (1) and be located at the control rod group (3) in the pressure vessel (4); Said positional detecting device (1) is installed in the outside of stroke case (7); Said positional detecting device (1) links to each other with CRDM (2), and said CRDM comprises hook parts, magnetic inversion line coil assembly, pressure-containing member and drive-rod part, and said drive-rod part links to each other with control rod group (3); It is characterized in that; Said positional detecting device (1) comprises a plurality of successive control unit, and said control module is divided into two groups of A, B alternately, and each control module comprises cell winding (8) and falls (9) two kinds of coils of excellent test coil; A plurality of cell windings are supplied power by a transformer T1, the end to end exit that is formed with two test induced voltages of the excellent test coil (9) that falls of each control module.