Reactor power control system and method

Abstract

The present invention discloses a system and method for reactor power control, the system comprising a control rod module (1) and a fluid supply module (2); wherein a reactor comprises a plurality of control rod modules (1), and the plurality of control rod modules (1) share a set of fluid supply modules (2). The method of the present invention replaces the original adjustment of slender rod-shaped solid control rods with adjustment of liquid, which makes the adjustment more precise; by filling and draining liquid, the current installation and removal of the slender rod-shaped solid control rods is replaced, and the installation, operation, repair and maintenance are convenient, and the defects of the slender rod-shaped solid control rods being easy to break and bend are overcome.

Description

Technical Field

[0001] The present invention belongs to the technical field of nuclear power, and in particular relates to a system and method for reactor power control. Background Art

[0002] Currently, reactor power control is mainly achieved by inserting and lifting control rods. This method has the following main shortcomings:

[0003] (1) The control rod is a long, thin rod-shaped structure, which takes up a lot of space and is difficult to lift in and out.

[0004] (2) Rod jamming and rod ejection accidents often occur during operation, threatening the safety of unit operation;

[0005] (3) During the commissioning phase of the high-temperature gas-cooled reactor, rod jamming occurred frequently and has not yet been completely resolved;

[0006] (4) The control rod material requirements are high and manufacturing is difficult;

[0007] (5) The control rods have poor precision in regulating reactor power. Summary of the Invention

[0008] The purpose of the present invention is to provide a system and method for reactor power control in response to the problems existing in current reactor power control.

[0009] To achieve the above object, the present invention adopts the following technical solutions:

[0010] A reactor power control system includes a control rod module and a fluid supply module. A reactor includes multiple control rod modules, and the multiple control rod modules share a set of fluid supply modules.

[0011] A further improvement of the present invention is that the control rod module includes an upper fluid box, a lower fluid box, a connecting straight pipe, an electric control slide valve, a relief valve, an isolation slide valve and a sealing slide valve; wherein,

[0012] The connecting straight pipe connects the upper fluid box and the lower fluid box arranged from top to bottom. The sealing slide valve is arranged in the lower fluid box and can slide up and down in the upper fluid box. The isolation slide valve is arranged in the connecting straight pipe and can slide up and down in the connecting straight pipe. The lower fluid box forms a circulation loop with the fluid supply module through the electronically controlled slide valve and the discharge valve.

[0013] A further improvement of the present invention is that the fluid supply module includes a pressure fluid box, a fluid return box, a pressure regulating pump and a system pressure control valve; wherein,

[0014] The outlet of the fluid return tank is connected to the inlet of the pressure-stabilizing pump, the outlet of the pressure-stabilizing pump is connected to the inlet of the pressure fluid tank, the first outlet of the pressure fluid tank is connected to the first inlet of the fluid return tank through the system pressure control valve; the second outlet of the pressure fluid tank is connected to the first inlet of the electric control slide valve, the first outlet of the lower fluid tank is connected to the second inlet of the electric control slide valve, the second outlet of the lower fluid tank is connected to the second inlet of the fluid return tank through the drain valve, the first outlet of the electric control slide valve is connected to the third inlet of the fluid return tank, and the second outlet of the electric control slide valve is connected to the inlet of the lower fluid tank.

[0015] A further improvement of the present invention is that an isolated space can be formed above and below the sealing slide valve in the upper fluid box, and the sealing slide valve can slide upward under the push of the fluid below the sealing slide valve. After the pressure of the fluid below the sealing slide valve is reduced, the sealing slide valve can slide downward under the action of gravity.

[0016] A further improvement of the present invention is that an isolated space can be formed above and below the isolation slide valve in the connecting straight pipe, and the isolation slide valve can slide upward under the push of the fluid below the isolation slide valve. After the pressure of the fluid below the isolation slide valve is reduced, the isolation slide valve can slide downward under the action of gravity.

[0017] A further improvement of the present invention is that the relief valve has a quick-opening function requirement, and after the relief valve receives a quick-opening instruction, it can quickly discharge the fluid in the lower fluid box back into the fluid return box.

[0018] A further improvement of the present invention is that the electronically controlled slide valve can accurately control the amount of fluid flowing from the pressure fluid tank to the lower fluid tank according to instructions; the electronically controlled slide valve can accurately control the amount of fluid flowing out of the lower fluid tank to the fluid return tank according to instructions.

[0019] A further improvement of the present invention is that the combined action of the pressure stabilizing pump and the system pressure control valve can ensure that the pressure of the pressure fluid box and its connected pipeline is stabilized to pressure C, which is sufficient to push the isolation slide valve to the top of the straight pipe.

[0020] A further improvement of the present invention is that the volume of the fluid return box meets the requirement that after all the fluid in the lower pipe of the isolation slide valve, the lower fluid box, and the pressure fluid box flows back to the fluid return box, the liquid level is not higher than the maximum liquid level; the volume of the fluid return box meets the requirement that after the lower pipe of the isolation slide valve, the lower fluid box, and the pressure fluid box are filled with fluid, the liquid level is not lower than the minimum liquid level.

[0021] A method for controlling reactor power, and a system for controlling reactor power according to the method, comprising the following steps:

[0022] Fluid A with neutron absorption capability is filled into the upper pipe of the isolation slide valve and the upper fluid tank. The amount of fluid A is greater than that when the isolation slide valve slides to the bottom of the connecting straight pipe, the liquid level of the upper fluid tank is higher than the lowest liquid level of the upper fluid tank. The amount of fluid A is less than that when the isolation slide valve slides to the top of the connecting straight pipe, the liquid level of the upper fluid tank is lower than the highest liquid level of the upper fluid tank. The sealing slide valve slides up and down with the change of the liquid level of the upper fluid tank, isolating the upper fluid from the surrounding environment.

[0023] Filling the fluid reflux box with fluid B that has no neutron absorption capability;

[0024] Start the pressure-stabilizing pump and fill the pressure fluid tank, lower fluid tank, and the lower pipe of the isolation slide valve with fluid B. Use the system pressure control valve to adjust the pressure of the pressure fluid tank to stabilize it at pressure C, which is sufficient to push the isolation slide valve to the top of the straight pipe.

[0025] When the reactor needs to increase its load, the electronically controlled slide valve is adjusted to increase the fluid B in the lower fluid tank. The fluid pushes the isolation slide valve upward, increasing the fluid B in the connecting straight pipe and reducing the fluid A. This weakens the control rod module's ability to absorb neutrons, and increases the reactor power.

[0026] When the reactor needs to reduce load, the electronically controlled slide valve is adjusted to reduce the fluid B in the lower fluid tank. The fluid pushes the isolation slide valve downward, increasing the fluid A in the connecting straight pipe and reducing the fluid B. This increases the neutron absorption capacity of the control rod module and reduces the reactor power.

[0027] When the reactor protection is activated, the relief valve opens quickly, the fluid B in the lower fluid tank is quickly discharged back into the fluid reflux tank, the connecting straight pipe is filled with fluid A, and the reactor power is reduced to zero.

[0028] Compared with the prior art, the present invention has the following advantages:

[0029] The present invention provides a reactor power control system, which has the following obvious advantages over currently used systems:

[0030] The present invention provides a reactor power control system that uses multiple control rod modules in conjunction with a set of fluid supply modules to replace slender rods that require frequent and precise movement, reducing the failure rate of rod jams and rod ejections, and making reactor operation safer.

[0031] Furthermore, the control rod module uses liquid control rods with neutron absorption capability. By adjusting the composition of the neutron-absorbing liquid, the reactivity value of the control rods can be easily adjusted, which facilitates the design of the reactor and makes the manufacturing of the control rods easier.

[0032] Furthermore, when the isolation slide valve slides to the bottom of the connecting straight tube, it is equivalent to the control rod module being fully inserted into the reactor. When the isolation slide valve slides to the top of the connecting straight tube, it is equivalent to the control rod module being fully pulled out of the reactor. The ratio of the difference between the effective proliferation coefficients of the reactor before and after the control rod module is inserted into the reactor to the effective proliferation coefficient of the reactor before insertion is called the reactivity value of the control rod module. The reactivity value of the control rod module 1 formed by fluid A should meet the requirements of reactor control.

[0033] The present invention provides a method for reactor power control, which has the following advantages:

[0034] The present invention changes the original adjustment of slender rod-shaped solid control rods to adjustment of liquid, which makes the adjustment more precise; by filling and draining liquid, it replaces the current installation and removal of slender rod-shaped solid control rods, making installation, operation, repair and maintenance convenient, and also overcomes the defects of slender rod-shaped solid control rods that are easy to break and bend; therefore, the present invention provides more reactor control methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a structural block diagram of a reactor power control system according to the present invention.

[0036] Description of reference numerals:

[0037] 1-Control rod module, 2-Fluid supply module, 3-Upper fluid box, 4-Connecting straight pipe, 5-Lower fluid box, 6-Electronic control slide valve, 7-Relief valve, 8-Isolation slide valve, 9-Sealing slide valve, 10-Pressure fluid box, 11-Fluid return box, 12-Pressure regulating pump, 13-System pressure control valve. DETAILED DESCRIPTION

[0038] The present invention is further described below with reference to the accompanying drawings.

[0039] like Figure 1 As shown, the present invention provides a reactor power control system, comprising a control rod module 1 and a fluid supply module 2; wherein, a reactor comprises a plurality of control rod modules 1, and the plurality of control rod modules 1 share a set of fluid supply modules 2.

[0040] The control rod module 1 includes an upper fluid tank 3, a lower fluid tank 5, a connecting straight pipe 4, an electrically controlled slide valve 6, a relief valve 7, an isolation slide valve 8, and a sealing slide valve 9. The connecting straight pipe 4 connects the upper fluid tank 3 and the lower fluid tank 5, which are arranged from top to bottom. The sealing slide valve 9 is arranged in the lower fluid tank 3 and can slide up and down in the upper fluid tank 3. The isolation slide valve 8 is arranged in the connecting straight pipe 4 and can slide up and down in the connecting straight pipe 4. The lower fluid tank 5 forms a circulation loop with the fluid supply module 2 through the electrically controlled slide valve 6 and the relief valve 7.

[0041] The fluid supply module 2 includes a pressure fluid box 10, a fluid return box 11, a pressure-stabilizing pump 12 and a system pressure control valve 13; wherein, the outlet of the fluid return box 11 is connected to the inlet of the pressure-stabilizing pump 12, the outlet of the pressure-stabilizing pump 12 is connected to the inlet of the pressure fluid box 10, and the first outlet of the pressure fluid box 10 is connected to the first inlet of the fluid return box 11 through the system pressure control valve 13; the second outlet of the pressure fluid box 10 is connected to the first inlet of the electric-controlled slide valve 6, the first outlet of the lower fluid box 5 is connected to the second inlet of the electric-controlled slide valve 6, the second outlet of the lower fluid box 5 is connected to the second inlet of the fluid return box 11 through the drain valve 7, the first outlet of the electric-controlled slide valve 6 is connected to the third inlet of the fluid return box 11, and the second outlet of the electric-controlled slide valve 6 is connected to the inlet of the lower fluid box 5.

[0042] The sealing slide valve 9 has certain sealing performance requirements, allowing an isolated space to be formed above and below the sealing slide valve 9; it also has certain weight requirements, allowing it to slide upward under the push of the fluid below the sealing slide valve 9, and then slide downward under the action of gravity after the pressure of the fluid below the sealing slide valve 9 decreases. The isolation slide valve 8 also has certain sealing performance requirements, allowing an isolated space to be formed above and below the isolation slide valve 8; it also has certain weight requirements, allowing it to slide upward under the push of the fluid below the isolation slide valve 8, and then slide downward under the action of gravity after the pressure of the fluid below the isolation slide valve 8 decreases.

[0043] Furthermore, the relief valve 7 has a quick-opening function. Upon receiving a quick-opening command, it can rapidly discharge the fluid from the lower fluid tank 5 back into the fluid return tank 11. The electrically controlled slide valve 6 precisely controls the amount of fluid flowing from the pressure fluid tank 10 into the lower fluid tank 5, and precisely controls the amount of fluid flowing from the lower fluid tank 5 into the fluid return tank 11, based on the command. The combined action of the pressure-stabilizing pump 12 and the system pressure control valve 13 ensures that the pressure in the pressure fluid tank 10 and its connected pipelines remains stable at pressure C, which is sufficient to push the isolation slide valve 8 to the top of the straight pipe 4.

[0044] The volume of the fluid return box 11 should meet the requirement that after all the fluid in the lower pipe of the isolation slide valve 8, the lower fluid tank 5, and the pressure fluid tank 10 flows back to the fluid return box 11, the liquid level is not higher than the maximum liquid level; the volume of the fluid return box 11 should meet the requirement that after the lower pipe of the isolation slide valve 8, the lower fluid tank 5, and the pressure fluid tank 10 are filled with fluid, the liquid level is not lower than the minimum liquid level.

[0045] The present invention provides a method for controlling reactor power, which specifically includes the following steps:

[0046] Fluid A with strong neutron absorption is filled into the upper pipe of the isolation slide valve 8 and the upper fluid tank 3. The amount of fluid A should be greater than when the isolation slide valve 8 slides to the bottom of the connecting straight pipe 4, when the liquid level in the upper fluid tank 3 is above the lowest level in the upper fluid tank 3, and less than when the isolation slide valve 8 slides to the top of the connecting straight pipe 4, when the liquid level in the upper fluid tank 3 is below the highest level in the upper fluid tank 3. The sealing slide valve 9 slides up and down with the change in the liquid level in the upper fluid tank 3, isolating the upper fluid from the surrounding environment. When the isolation slide valve 8 slides to the bottom of the connecting straight pipe 4, the control rod module 1 is fully inserted into the reactor. When the isolation slide valve 8 slides to the top of the connecting straight pipe 4, the control rod module 1 is fully removed from the reactor. The ratio of the difference in the effective proliferation coefficient of the reactor before and after the control rod module 1 is inserted into the reactor to the effective proliferation coefficient before insertion is called the reactivity value of the control rod module 1. The reactivity value of the control rod module 1 formed by fluid A should meet reactor control requirements.

[0047] Fill the fluid return box 11 with fluid B having weak neutron absorption capability;

[0048] Start the pressure-stabilizing pump 12 to fill the pressure fluid tank 10, the lower fluid tank 5, and the lower pipeline of the isolation slide valve 8 with fluid B. Use the system pressure control valve 13 to adjust the pressure of the pressure fluid tank 10 to stabilize it at C.

[0049] When the reactor needs to increase its load, the electrically controlled slide valve 6 is adjusted to increase the fluid B in the lower fluid tank 5. This fluid pushes the isolation slide valve 8 upward, increasing the fluid B in the connecting straight pipe 4 and reducing the fluid A. This weakens the neutron absorption capability of the control rod module 1 and increases the reactor power.

[0050] When the reactor needs to reduce its load, the electrically controlled slide valve 6 is adjusted to reduce the amount of fluid B in the lower fluid tank 5. This fluid pushes the isolation slide valve 8 downward, increasing the amount of fluid A in the connecting straight pipe 4 and reducing the amount of fluid B. This increases the neutron absorption capacity of the control rod module 1 and reduces the reactor power.

[0051] When the reactor protection is activated, the relief valve 7 opens quickly, the fluid B in the lower fluid tank 5 is quickly discharged back into the fluid return tank 11, the connecting straight pipe 4 is filled with fluid A, and the reactor power is reduced to zero.

Claims

1. A method for reactor power control, characterized in that: The method is based on a reactor power control system, which includes a control rod module (1) and a fluid supply module (2); wherein, A reactor includes a plurality of control rod modules (1), and the plurality of control rod modules (1) share a set of fluid supply modules (2); the control rod modules (1) use liquid control rods with neutron absorption capability, and include an upper fluid box (3), a lower fluid box (5), a connecting straight pipe (4), an electric control slide valve (6), a relief valve (7), an isolation slide valve (8), and a sealing slide valve (9); wherein the connecting straight pipe (4) connects the upper fluid box (3) and the lower fluid box (5) arranged from top to bottom, the sealing slide valve (9) is arranged in the lower fluid box (3) and can slide up and down in the upper fluid box (3), the isolation slide valve (8) is arranged in the connecting straight pipe (4) and can slide up and down in the connecting straight pipe (4), and the lower fluid box (5) forms a circulation loop with the fluid supply module (2) through the electric control slide valve (6) and the relief valve (7); The fluid supply module (2) comprises a pressure fluid box (10), a fluid return box (11), a pressure stabilizing pump (12) and a system pressure control valve (13); wherein the outlet of the fluid return box (11) is connected to the inlet of the pressure stabilizing pump (12), the outlet of the pressure stabilizing pump (12) is connected to the inlet of the pressure fluid box (10), the first outlet of the pressure fluid box (10) is connected to the first inlet of the fluid return box (11) through the system pressure control valve (13); the second outlet of the pressure fluid box (10) is connected to the first inlet of the electric control slide valve (6), the first outlet of the lower fluid box (5) is connected to the second inlet of the electric control slide valve (6), the second outlet of the lower fluid box (5) is connected to the second inlet of the fluid return box (11) through the drain valve (7), the first outlet of the electric control slide valve (6) is connected to the third inlet of the fluid return box (11), and the second outlet of the electric control slide valve (6) is connected to the inlet of the lower fluid box (5); An isolated space can be formed above and below the sealing slide valve (9) in the upper fluid box (3), and can slide upward under the push of the fluid below the sealing slide valve (9), and can slide downward under the action of gravity after the pressure of the fluid below the sealing slide valve (9) decreases; an isolated space can be formed above and below the isolation slide valve (8) in the connecting straight pipe (4), and can slide upward under the push of the fluid below the isolation slide valve (8), and can slide downward under the action of gravity after the pressure of the fluid below the isolation slide valve (8) decreases; The method comprises the following steps: A fluid A having neutron absorption capability is filled into the upper pipe of the isolation slide valve (8) and the upper fluid tank (3), wherein the amount of the fluid A is greater than the minimum liquid level of the upper fluid tank (3) when the isolation slide valve (8) slides to the bottom of the connecting straight pipe (4), and the amount of the fluid A is less than the maximum liquid level of the upper fluid tank (3) when the isolation slide valve (8) slides to the top of the connecting straight pipe (4), and the sealing slide valve (9) slides up and down as the liquid level of the upper fluid tank (3) changes, thereby isolating the upper fluid from the surrounding environment; Filling the fluid reflux box (11) with fluid B having no neutron absorption capability; Start the pressure stabilizing pump (12) to fill the pressure fluid tank (10), the lower fluid tank (5), and the lower pipe of the isolation slide valve (8) with fluid B, and use the system pressure control valve (13) to adjust the pressure of the pressure fluid tank (10) to stabilize it to pressure C, which is sufficient to push the isolation slide valve (8) to the top of the straight pipe (4); When the reactor needs to increase the load, the electronically controlled slide valve (6) is adjusted so that the fluid B in the lower fluid box (5) increases, and the fluid pushes the isolation slide valve (8) to move upward, the fluid B in the connecting straight pipe (4) increases, and the fluid A decreases, the neutron absorption ability of the control rod module (1) decreases, and the reactor power increases; When the reactor needs to reduce its load, the electronically controlled slide valve (6) is adjusted to reduce the fluid B in the lower fluid box (5). The fluid pushes the isolation slide valve (8) downward, and the fluid A in the connecting straight pipe (4) increases and the fluid B decreases. The neutron absorption capability of the control rod module (1) is enhanced, and the reactor power is reduced. When the reactor protection is activated, the discharge valve (7) opens quickly, the fluid B in the lower fluid box (5) is quickly discharged back into the fluid return box (11), the connecting straight pipe (4) is filled with fluid A, and the reactor power is reduced to zero.

2. A method for reactor power control according to claim 1, characterized in that: The discharge valve (7) has a quick-opening function requirement. After the discharge valve (7) receives a quick-opening instruction, it can quickly discharge the fluid in the lower fluid box (5) back into the fluid return box (11).

3. The method for reactor power control according to claim 1, wherein: The electrically controlled slide valve (6) can accurately control the amount of fluid flowing from the pressure fluid tank (10) into the lower fluid tank (5) according to instructions; the electrically controlled slide valve (6) can accurately control the amount of fluid flowing out of the lower fluid tank (5) into the fluid return tank (11) according to instructions.

4. The method for reactor power control according to claim 1, wherein: The combined action of the pressure stabilizing pump (12) and the system pressure control valve (13) can ensure that the pressure of the pressure fluid box (10) and its connected pipelines is stabilized to a pressure C, which is sufficient to push the isolation slide valve (8) to the top of the straight pipe (4).

5. The method for reactor power control according to claim 1, wherein: The volume of the fluid return box (11) is such that after all the fluid in the lower pipe of the isolation slide valve (8), the lower fluid box (5), and the pressure fluid box (10) flows back into the fluid return box (11), the liquid level thereof is not higher than the maximum liquid level thereof; and the volume of the fluid return box (11) is such that after the lower pipe of the isolation slide valve (8), the lower fluid box (5), and the pressure fluid box (10) are filled with fluid, the liquid level thereof is not lower than the minimum liquid level thereof.

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