Reactor protection method and device for high-temperature gas cooled reactor without off-plant power supply working condition

Abstract

The invention relates to the technical field of operation control of a high-temperature gas cooled reactor unit, and discloses a reactor protection method and device for a high-temperature gas cooled reactor without an off-plant power supply working condition, and the method comprises the steps: detecting the pressure difference of an emergency bus incoming switch, a main helium fan switch and a main water supply orifice plate flowmeter of the high-temperature gas cooled reactor unit; judging whether an emergency bus incoming switch tripping signal, a main helium fan tripping signal and a main water supply pore plate reverse pressure difference signal are generated or not; determining whether an off-plant power supply protection losing signal is generated or not based on the generation conditions of the emergency bus incoming switch tripping signal, the main helium fan tripping signal and the main water supply pore plate reverse pressure difference signal; and controlling the high-temperature gas cooled reactor unit to execute a preset reactor shutdown standard action based on the off-plant power supply loss protection signal, so that the reactor can be quickly shut down under the working condition that the high-temperature gas cooled reactor loses the off-plant power supply, and the safety of the reactor and equipment is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of operation control of high-temperature gas-cooled reactor units, and particularly relates to a reactor protection method and device for a high-temperature gas-cooled reactor under the condition of loss of off-site power supply. Background Art

[0002] The demonstration of high-temperature gas-cooled reactors, as a fourth-generation nuclear power technology, has attracted much attention in the industry due to its good safety and high thermal efficiency. The primary loop of its reactor uses helium as the cooling medium, which is driven by the main helium blower. The heat transfer between the primary and secondary loops is carried out by a once-through steam generator, and the superheated steam generated enters the steam turbine generator for energy conversion.

[0003] The settings of the main equipment and protection signals of high-temperature gas-cooled reactors are quite different from those of traditional pressurized water reactors. There are special equipment such as electromagnetic bearing type main helium blowers and once-through helical coil steam generators, and special protections for the mass flow ratio of the primary and secondary loops are set. Among them, the mass flow ratio signal of the primary and secondary loops is mainly a protection set for the load mismatch between the primary and secondary loops. This signal automatically takes effect when the reactor power is greater than 30% of the reactor rated power (Reactor Full Power, RFP), and is automatically blocked when it is less than 30% RFP. Its protection setting values are triggered both for the high limit and the low limit, and the operating median value is related to the power. During normal operation, it is necessary to control the helium flow rate in the primary loop and the feed water flow rate in the secondary loop to ensure that the mass flow ratio of the primary and secondary loops is within the operating limit range.

[0004] When the unit experiences a loss of off-site power (Station Black-Out, SBO) condition below 30% RFP, the mass flow ratio protection signal of the primary and secondary loops does not work, and only the single cold helium temperature can be used for protection, with a relatively long triggering time, which may be up to several hours or more. The reactor cannot be quickly shut down. At this time, equipment such as the main helium blower and the main feed water pump of the medium-pressure equipment have already stopped operating, but the control rods have not dropped and the feed water isolation valve has not been closed, seriously threatening the safety of the reactor and equipment. When the unit experiences a loss of off-site power condition above 30% RFP, both the main helium blower and the main feed water pump lose power and stop operating, but their flow coast-down is a gradually decreasing process. During this process, the mass flow ratio signal of the primary and secondary loops will also be triggered for about ten seconds, which is also not conducive to the safety of the reactor and the steam generator.

[0005] Therefore, the high-temperature reactor requires a protection method that can quickly shut down the reactor under the condition of loss of off-site power, drop the control rods, and achieve rapid isolation of the primary and secondary loops to ensure the safety of the reactor and equipment. Summary of the Invention

[0006] In view of this, the present invention provides a reactor protection method and device for a high-temperature gas-cooled reactor under the condition of loss of off-site power to solve the technical problem that the protection action of the high-temperature gas-cooled reactor is not timely enough under the condition of loss of off-site power, resulting in the reactor not being able to quickly shut down.

[0007] In a first aspect, the present invention provides a method for protecting a reactor under the condition of loss of off-site power in a high-temperature gas-cooled reactor, including: detecting the emergency bus incoming switch, the main helium blower switch, and the differential pressure of the main feedwater orifice flowmeter of the high-temperature gas-cooled reactor unit to determine whether an emergency bus incoming switch trip signal, a main helium blower trip signal, and a reverse differential pressure signal of the main feedwater orifice are generated; based on the generation of the emergency bus incoming switch trip signal, the main helium blower trip signal, and the reverse differential pressure signal of the main feedwater orifice, determining whether to generate a loss of off-site power protection signal; and based on the loss of off-site power protection signal, controlling the high-temperature gas-cooled reactor unit to perform a pre-set standard reactor shutdown action.

[0008] By detecting the emergency bus incoming switch, the main helium blower switch, and the differential pressure of the main feedwater orifice flowmeter of the high-temperature gas-cooled reactor unit, the present invention determines whether an emergency bus incoming switch trip signal, a main helium blower trip signal, and a reverse differential pressure signal of the main feedwater orifice are generated. Based on the generation of these signals, it determines whether to generate a loss of off-site power protection signal. And based on the loss of off-site power protection signal, it controls the high-temperature gas-cooled reactor unit to perform a pre-set standard reactor shutdown action. When the condition of loss of off-site power in the high-temperature gas-cooled reactor occurs, it can promptly detect this condition, and then perform the standard reactor shutdown action to protect the reactor, enabling the reactor to quickly shut down and protecting the high-temperature gas-cooled reactor unit.

[0009] Optionally, based on the generation of the emergency bus incoming switch trip signal, the main helium blower trip signal, and the reverse differential pressure signal of the main feedwater orifice, determining whether to generate a loss of off-site power protection signal includes: performing logical analysis based on the generation of the emergency bus incoming switch trip signal, the main helium blower trip signal, and the reverse differential pressure signal of the main feedwater orifice; if at the same time as the emergency bus incoming switch trip signal is generated, at least one of the main helium blower trip signal or the reverse differential pressure signal of the main feedwater orifice is also generated, then a loss of off-site power protection signal is generated.

[0010] In this method, by logically analyzing the combination of the emergency bus incoming switch trip signal, the main helium blower trip signal, and the reverse differential pressure signal of the main feedwater orifice, it avoids mis-triggering by a single signal, can more accurately identify the condition of loss of off-site power, optimizes the protection strategy, and reduces unnecessary reactor shutdowns.

[0011] Optionally, the emergency bus incoming switch, the main helium blower switch, and the differential pressure of the main feedwater orifice plate flowmeter of the high-temperature gas-cooled reactor unit are detected to determine whether an emergency bus incoming switch trip signal, a main helium blower trip signal, and a reverse differential pressure signal of the main feedwater orifice plate are generated, including: detecting the trip signal of the under-voltage relay of the emergency bus incoming switch of the high-temperature gas-cooled reactor unit, and generating an emergency bus incoming switch trip signal when the trip signals of the under-voltage relays reach or exceed the first preset quantity; detecting the trip signal of the circuit breaker of the main helium blower of the high-temperature gas-cooled reactor unit, and generating a main helium blower trip signal when the trip signals of the circuit breakers reach or exceed the second preset quantity; detecting the differential pressure of the main feedwater orifice plate flowmeter of the high-temperature gas-cooled reactor unit, and generating a reverse differential pressure signal of the main feedwater orifice plate when the values of the differential pressures of the main feedwater orifice plate flowmeters reach or exceed the third preset quantity and are less than zero.

[0012] In this method, the abnormal conditions of the under-voltage relay, the circuit breaker, and the differential pressure of the flowmeter are quantitatively judged, which can avoid misjudgment caused by accidental failures of individual devices and improve the stability and reliability of the protection system.

[0013] Optionally, the standard reactor shutdown actions include closing the main steam isolation valve after a 30-second delay; correspondingly, after controlling the high-temperature gas-cooled reactor unit to perform the preset standard reactor shutdown actions, it includes: outputting a signal to open the main steam isolation valve after an interval of the first preset time; detecting the decrease amplitude of the main steam pressure, and closing the main steam isolation valve again when the main steam pressure drops by more than the set differential pressure value, and the set differential pressure value is 1 Mpa - 3 Mpa.

[0014] In this method, the step-by-step control method can avoid too large a steam drop amplitude, reduce the impact on equipment caused by too large a change in the main steam pressure, and ensure the safe operation of the steam generator.

[0015] Optionally, the standard reactor shutdown actions further include controlling the safety rod and the regulating rod to drop, stopping the main helium blower, closing the main helium blower baffle, stopping the main feedwater pump, and closing the main feedwater isolation valve.

[0016] In this method, the reactor can be quickly shut down through the above protection actions.

[0017] Optionally, after controlling the high-temperature gas-cooled reactor unit to perform the preset standard reactor shutdown actions, it further includes: controlling the main steam drain valve to close.

[0018] In this method, by closing the main steam drain valve, the residual high-temperature and high-pressure steam in the main steam pipeline can be used to continue supplying shaft seal steam.

[0019] In a second aspect, the present invention provides a reactor protection device for a high-temperature gas-cooled reactor under the condition of loss of off-site power supply, including: an initial signal detection module, configured to detect the emergency bus incoming switch, the main helium blower, and the differential pressure of the main feedwater orifice flowmeter of the high-temperature gas-cooled reactor unit, and determine whether an emergency bus incoming switch trip signal, a main helium blower trip signal, and a reverse differential pressure signal of the main feedwater orifice are generated; a power loss signal generation module, configured to determine whether to generate an off-site power loss protection signal based on the generation conditions of the emergency bus incoming switch trip signal, the main helium blower trip signal, and the reverse differential pressure signal of the main feedwater orifice; an action execution module, configured to control the high-temperature gas-cooled reactor unit to execute a pre-set standard reactor shutdown action based on the off-site power loss protection signal.

[0020] In a third aspect, the present invention provides a computer device, including: a memory and a processor, which are communicatively connected to each other. The memory stores computer instructions, and the processor executes the computer instructions to execute the reactor protection method for a high-temperature gas-cooled reactor under the condition of loss of off-site power supply according to the first aspect or any corresponding embodiment thereof.

[0021] In a fourth aspect, the present invention provides a computer-readable storage medium, on which computer instructions are stored, and the computer instructions are used to cause a computer to execute the reactor protection method for a high-temperature gas-cooled reactor under the condition of loss of off-site power supply according to the first aspect or any corresponding embodiment thereof.

[0022] In a fifth aspect, the present invention provides a computer program product, including computer instructions, and the computer instructions are used to cause a computer to execute the reactor protection method for a high-temperature gas-cooled reactor under the condition of loss of off-site power supply according to the first aspect or any corresponding embodiment thereof. Description of the Drawings

[0023] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0024] Figure 1 is a schematic flow chart of a reactor protection method for a high-temperature gas-cooled reactor under the condition of loss of off-site power supply according to an embodiment of the present invention;

[0025] Figure 2 is a schematic flow chart of another reactor protection method for a high-temperature gas-cooled reactor under the condition of loss of off-site power supply according to an embodiment of the present invention;

[0026] Figure 3 is a schematic diagram of the mass flow ratio of the primary and secondary circuits according to an embodiment of the present invention;

[0027] Figure 4 It is the structural block diagram of the reactor protection device under the condition of loss of off-site power in the high-temperature gas-cooled reactor of the embodiment of the present invention;

[0028] Figure 5 It is the schematic diagram of the hardware structure of the computer device of the embodiment of the present invention. Specific embodiments

[0029] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts shall fall within the protection scope of the present invention.

[0030] At present, the setting of the main equipment protection signal of the high-temperature gas-cooled reactor mainly uses the mass flow ratio signal of the primary and secondary loops for protection.

[0031] The setting value g of the mass flow ratio of the primary and secondary loops 1 The calculation formula is:

[0032]

[0033] Among them, G 1 (n) is the flow rate of the primary loop, G 2 (n) is the flow rate of the secondary loop, P is the relative power, and k 0 is an adjustable coefficient. The high setting value is g 1 +1, and the low setting value is g 1 -1. In addition, in order to avoid false triggering, delay filtering is added. The schematic diagram of the mass flow ratio of the primary and secondary loops is as Figure 3 shown.

[0034] When the unit loses off-site power below 30% RFP, this protection signal does not work. When the unit loses off-site power above 30% RFP, the main helium blower stops running, and the coast-down time of the speed is about 2 min (to 5% speed), and the coast-down time of the main feed water pump is about 1 min (to 5% speed). The flow rate changes and the coast-down conditions of the speeds of the two are similar. The mass flow ratio of the primary and secondary loops will not reach the trigger setting value in a short time. Coupled with the existence of delay filtering, the trigger time will exceed 10 s. Therefore, when the unit is in a high-power condition and loses off-site power, the reactor cannot quickly shut down automatically, and the safety risk is relatively high.

[0035] In view of this, the present invention provides a reactor protection method for a high-temperature gas-cooled reactor under the condition of loss of off-site power supply, so as to solve the technical problem that the reactor cannot be quickly shut down due to untimely protection action of the high-temperature gas-cooled reactor under the condition of loss of off-site power supply.

[0036] According to an embodiment of the present invention, there is provided an embodiment of a reactor protection method for a high-temperature gas-cooled reactor under the condition of loss of off-site power supply. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although the logical order is shown in the flowchart, in some cases, the steps shown or described herein can be executed in a different order.

[0037] In this embodiment, a reactor protection method for a high-temperature gas-cooled reactor under the condition of loss of off-site power supply is provided, which can be used for an intelligent control terminal, such as Figure 1 As shown, the process includes the following steps:

[0038] Step S101, detect the emergency bus incoming switch, the main helium blower switch and the differential pressure of the main feedwater orifice flowmeter of the high-temperature gas-cooled reactor unit, and determine whether an emergency bus incoming switch trip signal, a main helium blower trip signal and a main feedwater orifice reverse differential pressure signal are generated.

[0039] Under the condition of loss of off-site power supply, important equipment such as the main helium blower, the main feedwater pump, and the steam turbine trip, but the reactor control rods and the main isolation valves of the secondary circuit are all powered by the safety bus, and there are standby batteries, so there is no power loss for a short time under the condition of loss of off-site power supply. Therefore, it is necessary to generate a new reactor protection signal to automatically trigger the reactor protection shutdown and avoid manual intervention by the operator.

[0040] Specifically, during normal operation, the emergency bus incoming switch is in the closed state and will open under the condition of loss of off-site power supply, which has good representativeness. At the same time, this device is also a safety-class device, and the switch quantity feedback of its relay can be used as one of the protection trigger signals. The emergency bus incoming switch trip signal is generally used as the start signal of the emergency diesel generator and is also the representative signal of the loss of power of the emergency bus, that is, the typical signal of the power loss condition.

[0041] The trip signal of the primary helium blower selects the digital quantity of the safety-class medium-voltage circuit breaker as one of the trigger signals. From the perspective of economy, the circuit breaker of the primary helium blower in the high-temperature reactor is composed of two series-connected medium-voltage circuit breakers. Therefore, the one-out-of-two principle is adopted, that is, the trip of any medium-voltage circuit breaker generates the trip signal of the primary helium blower. As a typical power-loss shutdown signal of the equipment unique to the high-temperature reactor, when the high-temperature gas-cooled reactor shuts down, the primary helium blower needs to be shut down immediately, so that the primary loop circulation stops quickly. Under the power-loss condition, the switch of the medium-voltage bus of the primary helium blower trips, and the primary helium blower coasts to a stop. However, at this time, the reactor may not have triggered the protection signal yet. Therefore, the trip signal of the primary helium blower is selected as the trigger signal. Compared with the traditional pressurized water reactor, the trip signal of the primary helium blower is a signal unique to the high-temperature reactor.

[0042] The reverse pressure difference signal of the main feedwater orifice plate refers to the atypical signal when the pressure difference of the main feedwater orifice plate flowmeter < 0, which is a signal of a specific power-loss condition. During normal operation, the pressure difference of the orifice plate of the main feedwater flowmeter ≥ 0, which is converted into a 4 mA - 20 mA current signal, and through calculation, a secondary loop flow signal is generated to participate in the control and protection of the unit. When the off-site power supply is lost, because the closing time of the main steam valve and regulating valve of the steam turbine is less than the opening time of the steam turbine bypass valve, and the power supply switch of the main feedwater pump has been disconnected under the power-loss condition, there is a lack of power source, and the sudden rapid shutdown at the end will cause the phenomenon of reverse pressure difference in the orifice plate. Therefore, the reverse pressure difference signal of the main feedwater orifice plate is selected as the trigger signal for unconventional means.

[0043] Step S102: Based on the generation conditions of the emergency bus incoming switch trip signal, the primary helium blower trip signal, and the reverse pressure difference signal of the main feedwater orifice plate, determine whether to generate the off-site power loss protection signal.

[0044] Specifically, when the off-site power loss condition occurs, generally, the emergency bus incoming switch trip signal, the primary helium blower trip signal, and the reverse pressure difference signal of the main feedwater orifice plate will be generated simultaneously. In order to achieve signal redundancy and avoid judgment errors that are likely to occur when detecting whether the off-site power loss condition occurs through a single signal, a composite logic operation is performed by combining the emergency bus incoming switch trip signal, the primary helium blower trip signal, and the reverse pressure difference signal of the main feedwater orifice plate to determine whether the off-site power loss condition occurs.

[0045] For example, when at least one signal or at least two signals of the emergency bus incoming switch trip signal, the primary helium blower trip signal, and the reverse pressure difference signal of the main feedwater orifice plate occur simultaneously, it is determined that the off-site power loss condition occurs, and then the off-site power loss protection signal is generated.

[0046] Step S103: Based on the off-site power loss protection signal, control the high-temperature gas-cooled reactor unit to execute the preset standard actions for reactor shutdown.

[0047] The standard reactor shutdown actions are pre-set shutdown actions for the condition of loss of off-site power, based on the safety settings of the unit. Through the above protection actions, the reactor can be quickly shut down under the condition of loss of off-site power.

[0048] Specifically, the process of the high-temperature reactor experiencing a loss of off-site power is as follows (in chronological order):

[0049] The entire plant loses power, the steam turbine generator trips, and the generator outlet circuit breaker opens (0.5 ms); the 6 kV bus loses power, and medium-voltage loads such as the main helium blower, main feed water pump, condensate pump, and circulating water pump trip (1 s); the emergency bus incoming switch trips, and the emergency diesel generator starts automatically (1 s); a loss of off-site power protection signal is generated and triggers reactor protection shutdown. As Figure 2 shown, the standard reactor shutdown actions are as follows:

[0050] 1. Control the safety rods and regulating rods to drop

[0051] The safety rods are used for reactor safety protection. It has a strong neutron absorption capacity. During normal reactor operation, the safety rods are withdrawn from the reactor. When an emergency or accident occurs in the reactor, the safety rods fall by their own weight to stop the nuclear fission reaction.

[0052] The regulating rods are used to adjust the reactor power level. When increasing the reactor power, some regulating rods are withdrawn, and conversely, when reducing the reactor power, some regulating rods are inserted. During an emergency reactor shutdown, they will also all drop.

[0053] 2. Stop the main helium blower

[0054] The primary coolant circuit medium of the high-temperature gas-cooled reactor is helium, which is driven in a cycle by the main helium blower. After an emergency shutdown, the purpose of stopping the main helium blower is to quickly terminate the primary coolant circuit cycle. The shorter the time for the forced circulation of the primary coolant circuit to stop, the smaller the temperature and pressure rise of the coolant during this period, which is more beneficial for controlling the pressure rise in the primary coolant circuit, reducing the possibility of the primary coolant circuit safety valve opening, and maintaining the integrity of the pressure vessel.

[0055] 3. Close the main helium blower damper

[0056] The main helium blower damper is located at the outlet of the main helium blower. Closing the main helium blower damper can better cut off the primary coolant circuit cycle.

[0057] 4. Stop the main feed water pump

[0058] The function of stopping the main feed water pump is to terminate the secondary coolant circuit cycle and prevent cold water from entering the high-temperature steam generator, affecting the temperature of the primary coolant circuit and the safety of the steam generator.

[0059] 5. Close the main feed water isolation valve

[0060] The function of closing the main feed water isolation valve is to isolate the feed water side of the secondary circuit from the nuclear island side.

[0061] 6. Close the main steam isolation valve after a 30 - second delay

[0062] The main steam isolation valve is located at the outlet of the steam generator. Closing the main steam isolation valve also serves to isolate the steam side of the secondary circuit. The purpose of the 30 - second delay is to prevent the high - temperature helium gas in the primary circuit from heating the main steam through the steam generator, which may lead to phenomena such as over - pressure of the main steam pressure and actuation of the safety valve. Delayed closing can reduce the amplitude of the rise in the main steam pressure.

[0063] After the emergency diesel generator starts (within 20 s), important loads are loaded in accordance with the load - carrying sequence. The reactor maintains the shutdown state, and the primary and secondary circuits are isolated (for 1 min). The residual heat of the reactor is removed by the passive residual heat removal system (long - term). Restore the power supply, and the load of the emergency busbar power supply is switched to the normal operation power supply mode. The primary and secondary circuit systems are restored, and the conditions for restart are met.

[0064] In the embodiment of the present invention, by detecting the emergency busbar incoming switch, the main helium blower switch, and the differential pressure of the main feed water orifice plate flowmeter of the high - temperature gas - cooled reactor unit, it is judged whether an emergency busbar incoming switch trip signal, a main helium blower trip signal, and a reverse differential pressure signal of the main feed water orifice plate are generated. Based on the generation conditions of the emergency busbar incoming switch trip signal, the main helium blower trip signal, and the reverse differential pressure signal of the main feed water orifice plate, it is determined whether to generate a loss - of - off - site - power protection signal. Based on the loss - of - off - site - power protection signal, the high - temperature gas - cooled reactor unit is controlled to execute the preset reactor shutdown standard actions. When the loss - of - off - site - power condition of the high - temperature gas - cooled reactor occurs, this condition can be detected in time, and then the reactor shutdown standard actions are executed to protect the reactor, enabling the reactor to quickly shut down and protecting the high - temperature gas - cooled reactor unit.

[0065] The selected emergency busbar incoming switch trip signal, main helium blower trip signal, and reverse differential pressure signal of the main feed water orifice plate in the embodiment of the present invention are all safety - class equipment signals on the nuclear island side, and both the emergency busbar incoming switch trip signal and the main helium blower trip signal belong to electrical switch quantities. Combining the three for judging the loss - of - off - site - power condition can improve the reliability and accuracy of the condition judgment result.

[0066] In some embodiments, step S102, based on the generation conditions of the emergency busbar incoming switch trip signal, the main helium blower trip signal, and the reverse differential pressure signal of the main feed water orifice plate, determining whether to generate a loss - of - off - site - power protection signal includes:

[0067] Step S1021, perform logical analysis based on the generation conditions of the emergency busbar incoming switch trip signal, the main helium blower trip signal, and the reverse differential pressure signal of the main feed water orifice plate.

[0068] Step S1022, if, while generating the tripping signal of the emergency bus incoming switch, at least one of the main helium blower tripping signal or the reverse differential pressure signal of the main feedwater orifice plate is also generated, then generate the off-site power loss protection signal.

[0069] Specifically, when the logical judgment satisfies the tripping signal of the emergency bus incoming switch and (the main helium blower tripping signal or the reverse differential pressure signal of the main feedwater orifice plate), generate the off-site power loss protection signal to avoid false triggering by a single signal.

[0070] In some embodiments, in step S101, detect the emergency bus incoming switch, the main helium blower, and the differential pressure of the main feedwater orifice plate flowmeter of the high-temperature gas-cooled reactor unit, and determine whether the tripping signal of the emergency bus incoming switch, the main helium blower tripping signal, and the reverse differential pressure signal of the main feedwater orifice plate are generated, including:

[0071] Step S1011, detect the tripping signal of the under-voltage relay of the emergency bus incoming switch of the high-temperature gas-cooled reactor unit. When the tripping signals of more than the first preset number of under-voltage relays appear, generate the tripping signal of the emergency bus incoming switch.

[0072] In an example, the two-out-of-three principle is adopted, that is, the first preset number is two, and the total number of under-voltage relays of the emergency bus incoming switch is three. Then, when two or more under-voltage relays trip, generate the tripping signal of the emergency bus switch.

[0073] For example, the emergency bus incoming switch is 400V and is provided with three under-voltage relays, which are also safety-class. When the off-site power loss condition occurs, the 6KV medium-voltage bus loses power, and the downstream 400V emergency bus also quickly loses power. When two or more of the three under-voltage relays trip, generate the tripping signal of the emergency bus incoming switch, and this signal is also used as the starting signal of the emergency diesel generator.

[0074] Step S1012, detect the tripping signal of the circuit breaker of the main helium blower of the high-temperature gas-cooled reactor unit. When the tripping signals of the second preset number or more of circuit breakers appear, generate the main helium blower tripping signal.

[0075] Exemplarily, the one-out-of-two principle is adopted, that is, the second preset number is one, and the circuit breaker of the main helium blower is composed of two safety-class medium-voltage circuit breakers in series. If any one of them trips, the main helium blower will lose power and stop operating.

[0076] Step S1013, detect the differential pressure of the main feedwater orifice plate flowmeter of the high-temperature gas-cooled reactor unit. When the values of the differential pressure of the third preset number or more of the main feedwater orifice plate flowmeters are less than zero, generate the reverse differential pressure signal of the main feedwater orifice plate.

[0077] Exemplarily, the principle of taking two out of four is adopted, that is, the third preset quantity is two, and four main feedwater orifice plate flowmeters are provided. When the differential pressure of two or more main feedwater flowmeter orifice plates is less than zero, a reverse differential pressure signal of the main feedwater orifice plate is generated.

[0078] In this method, through the logic of taking multiple or taking one out of multiple, the abnormal conditions of the loss-of-pressure relay, circuit breaker, and flowmeter differential pressure are quantitatively judged, which can avoid misjudgment caused by accidental failures of individual devices and improve the stability and reliability of the protection system.

[0079] In some embodiments, the standard action for reactor shutdown includes closing the main steam isolation valve after a 30-second delay; correspondingly, in step S103, after controlling the high-temperature gas-cooled reactor unit to perform the preset standard action for reactor shutdown, it includes:

[0080] Step S104, output a signal to open the main steam isolation valve after an interval of the first preset time, and open the main steam isolation valve based on the main steam isolation valve signal.

[0081] Step S105, detect the decreasing amplitude of the main steam pressure. When the main steam pressure drops by more than the set differential pressure value, close the main steam isolation valve again, and the set differential pressure value is 1 Mpa - 3 Mpa.

[0082] Specifically, the first preset time can be 5 s, 10 s, 20 s, etc. Send a signal to open the main steam isolation valve again, aiming to utilize the steam in the steam generator and the main steam pipeline to supply high-temperature and high-pressure shaft seal steam. At this time, what needs to be concerned about is the decreasing amplitude of the main steam pressure. In order to ensure the safe operation of the steam generator and avoid too large a decreasing amplitude of the steam, when the pressure drops by more than the set differential pressure value ΔP, the main steam isolation valve is closed again. During this process, the shaft seal steam can be switched to the auxiliary electric boiler for supply, or operations such as breaking the vacuum can be taken.

[0083] Among them, the set differential pressure value ΔP can be 1 Mpa, 2 Mpa, 3 Mpa, etc. The specific value can be set according to the actual working conditions.

[0084] In this method, adopting a step-by-step control method can avoid too large a decreasing amplitude of the steam, reduce the impact on the equipment caused by too large a change in the main steam pressure, and ensure the safe operation of the steam generator.

[0085] In some embodiments, after controlling the high-temperature gas-cooled reactor unit to perform the preset standard action for reactor shutdown, it further includes:

[0086] Step S106, control the main steam drain valve to close.

[0087] Specifically, when the off-site power supply loss condition is detected in the embodiments of the present invention, on the basis of the standard reactor shutdown operation, the action of closing the main steam drain valve is added. The purpose is to use the residual high-temperature and high-pressure steam in the main steam pipeline to continue supplying shaft seal steam, and then close it after a set time, such as 1 minute. In general power plants, after the steam turbine is shut down, the main steam pipeline drain valve will be interlocked to open to prevent water accumulation in the pipeline due to steam condensation, which may affect the next unit startup (water accumulation will cause pipeline vibration, water hammer and other phenomena).

[0088] In this way, by closing the main steam drain valve, the residual high-temperature and high-pressure steam in the main steam pipeline can be used to continue supplying shaft seal steam.

[0089] The reactor protection method for the loss of off-site power supply condition of the high-temperature gas-cooled reactor in the embodiments of the present invention detects the emergency bus incoming switch, the main helium blower switch and the differential pressure of the main feed water orifice plate flowmeter of the high-temperature gas-cooled reactor unit to determine whether an emergency bus incoming switch trip signal, a main helium blower trip signal and a reverse differential pressure signal of the main feed water orifice plate are generated. Based on the generation of the emergency bus incoming switch trip signal, the main helium blower trip signal and the reverse differential pressure signal of the main feed water orifice plate, it is determined whether a loss of off-site power supply protection signal is generated. Based on the loss of off-site power supply protection signal, the high-temperature gas-cooled reactor unit is controlled to perform the pre-set standard reactor shutdown operation. When the loss of off-site power supply condition of the high-temperature gas-cooled reactor occurs, this condition can be detected in time, and then the standard reactor shutdown operation is executed to protect the reactor, so that the reactor can be quickly shut down, the control rods can be dropped, and the primary and secondary circuits can be isolated. It solves the problem that when the off-site power supply is lost below 30% RFP power, the mass flow ratio of the primary and secondary circuits is not effective and the reactor cannot be quickly shut down. At the same time, it also solves the problem that when the off-site power supply is lost above 30% RFP, the flows of the primary and secondary circuits coast down simultaneously, the mass flow ratio of the primary and secondary circuits is triggered slowly, and the reactor cannot be quickly shut down.

[0090] The selected emergency bus incoming switch trip signal, the main helium blower trip signal and the reverse differential pressure signal of the main feed water orifice plate are all safety-class equipment signals on the nuclear island side, and both the emergency bus incoming switch trip signal and the main helium blower trip signal belong to electrical switch quantities. Combining the three to judge the off-site power supply loss condition can improve the reliability and accuracy of the condition judgment result. At the same time, the condition judgment logic adopts a composite logic, which can avoid signal mis-triggering.

[0091] After detecting the off-site power supply loss condition and after performing the standard reactor shutdown operation, the decrease amplitude of the main steam pressure is also detected. When the main steam pressure drops by more than 1 - 3 MPa, the main steam isolation valve is closed again, and in addition, controlling the closing of the main steam drain valve can reduce the impact of excessive main steam pressure change on the equipment, ensure the safe operation of the steam generator, and can provide targeted protection for the reactor when the off-site power supply is lost.

[0092] An embodiment of the present invention also provides a reactor protection device for the high-temperature gas-cooled reactor under the condition of loss of off-site power supply, as Figure 4 shown. The device includes:

[0093] An initial signal detection module 401, configured to detect the emergency bus incoming switch, the main helium blower, and the differential pressure of the main feedwater orifice flowmeter of the high-temperature gas-cooled reactor unit, and determine whether an emergency bus incoming switch trip signal, a main helium blower trip signal, and a main feedwater orifice reverse differential pressure signal are generated;

[0094] A power loss signal generation module 402, configured to determine whether to generate an off-site power supply loss protection signal based on the generation conditions of the emergency bus incoming switch trip signal, the main helium blower trip signal, and the main feedwater orifice reverse differential pressure signal;

[0095] An action execution module 403, configured to control the high-temperature gas-cooled reactor unit to execute a preset reactor shutdown standard action based on the off-site power supply loss protection signal.

[0096] The reactor protection device for the high-temperature gas-cooled reactor under the condition of loss of off-site power supply in the embodiment of the present invention detects the emergency bus incoming switch, the main helium blower switch, and the differential pressure of the main feedwater orifice flowmeter of the high-temperature gas-cooled reactor unit, determines whether an emergency bus incoming switch trip signal, a main helium blower trip signal, and a main feedwater orifice reverse differential pressure signal are generated, determines whether to generate an off-site power supply loss protection signal based on the generation conditions of the emergency bus incoming switch trip signal, the main helium blower trip signal, and the main feedwater orifice reverse differential pressure signal, and controls the high-temperature gas-cooled reactor unit to execute a preset reactor shutdown standard action based on the off-site power supply loss protection signal. When the off-site power supply loss condition occurs in the high-temperature gas-cooled reactor, this condition can be detected in time, and then the reactor shutdown standard action is executed to protect the reactor, so that the reactor shuts down quickly, the control rods drop, and the primary and secondary circuits are isolated, solving the problem that when the off-site power supply loss condition occurs below 30% of the RFP power, the mass flow ratio of the primary and secondary circuits is not effective and the reactor cannot shut down quickly. At the same time, it can also solve the problem that when the off-site power supply loss condition occurs above 30% of the RFP power, the flows of the primary and secondary circuits coast down simultaneously, the mass flow ratio of the primary and secondary circuits is triggered slowly, and the reactor cannot shut down quickly.

[0097] The selected emergency bus incoming switch trip signal, main helium blower trip signal, and main feedwater orifice reverse differential pressure signal are all nuclear island side safety-class equipment electrical signals, and both the emergency bus incoming switch trip signal and the main helium blower trip signal are digital signals. Combining the three to judge the off-site power supply loss condition can improve the reliability and accuracy of the condition judgment result.

[0098] Further, the power loss signal generation module 402 includes:

[0099] A logic analysis module for performing logic analysis based on the generation of an emergency bus incoming switch trip signal, a main helium blower trip signal, and a reverse differential pressure signal of the main feedwater orifice plate;

[0100] A logic execution module for generating a loss of off-site power protection signal if at least one of the main helium blower trip signal or the reverse differential pressure signal of the main feedwater orifice plate is generated while the emergency bus incoming switch trip signal is generated.

[0101] Furthermore, the initial signal detection module 401 includes:

[0102] An emergency bus detection module for detecting the trip signal of the under-voltage relay of the emergency bus incoming switch of the high-temperature gas-cooled reactor unit, and generating an emergency bus incoming switch trip signal when the trip signals of the under-voltage relays reach the first preset quantity or more;

[0103] A main helium blower detection module for detecting the trip signal of the circuit breaker of the main helium blower of the high-temperature gas-cooled reactor unit, and generating a main helium blower trip signal when the trip signals of the circuit breakers reach the second preset quantity or more;

[0104] A main feedwater orifice plate detection module for detecting the differential pressure of the main feedwater orifice plate flowmeter of the high-temperature gas-cooled reactor unit, and generating a reverse differential pressure signal of the main feedwater orifice plate when the values of the differential pressures of the main feedwater orifice plate flowmeters reach the third preset quantity or more and are less than zero.

[0105] Furthermore, the standard reactor trip actions include closing the main steam isolation valve after a 30-second delay; correspondingly, the reactor protection device for the high-temperature gas-cooled reactor in the loss of off-site power condition further includes:

[0106] A main steam isolation valve opening module for outputting a main steam isolation valve opening signal after an interval of the first preset time, and opening the main steam isolation valve based on the main steam isolation valve signal;

[0107] A pressure detection module for detecting the decrease amplitude of the main steam pressure, and closing the main steam isolation valve again when the main steam pressure drops by more than the set differential pressure value, and the set differential pressure value is 1 Mpa - 3 Mpa.

[0108] Furthermore, the standard reactor trip actions also include controlling the safety rods and regulating rods to drop, stopping the main helium blower, closing the main helium blower baffle, stopping the main feedwater pump, and closing the main feedwater isolation valve.

[0109] Furthermore, after controlling the high-temperature gas-cooled reactor unit to perform the preset standard reactor trip actions, the reactor protection device for the high-temperature gas-cooled reactor in the loss of off-site power condition further includes:

[0110] A drain valve closing module for controlling the main steam drain valve to close.

[0111] An embodiment of the present invention also provides a schematic structural diagram of a computer device, as Figure 5 shown. The computer device includes: one or more processors 10, a memory 20, and interfaces for connecting various components, including a high-speed interface and a low-speed interface. Each component communicates with each other using different buses and can be installed on a common motherboard or installed in other ways as needed. The processor can process instructions executed within the computer device, including instructions stored in the memory or on the memory to display graphical information of the GUI on an external input / output device (such as a display device coupled to the interface). In some alternative embodiments, if necessary, multiple processors and / or multiple buses can be used together with multiple memories and multiple memories. Similarly, multiple computer devices can be connected, and each device provides some necessary operations (for example, as a server array, a set of blade servers, or a multi-processor system). Figure 5 In

[0112] FIG. 4, one processor 10 is taken as an example.

[0113] The processor 10 may be a central processing unit, a network processor, or a combination thereof. Among them, the processor 10 may further include a hardware chip. The above hardware chip may be an application-specific integrated circuit, a programmable logic device, or a combination thereof. The above programmable logic device may be a complex programmable logic device, a field programmable gate array, a generic array logic, or any combination thereof.

[0114] The memory 20 stores instructions executable by at least one processor 10, so that at least one processor 10 executes the method shown in the above embodiments.

[0115] The memory 20 may include a storage program area and a storage data area. Among them, the storage program area may store an operating system and application programs required for at least one function; the storage data area may store data created according to the use of the computer device. In addition, the memory 20 may include a high-speed random access memory and may also include a non-transitory memory, such as at least one disk storage device, a flash memory device, or other non-transitory solid-state storage devices. In some alternative embodiments, the memory 20 may optionally include a memory remotely set relative to the processor 10, and these remote memories may be connected to the computer device through a network. Examples of the above network include but are not limited to the Internet, an enterprise intranet, a local area network, a mobile communication network, and a combination thereof.

[0116] The computer device further includes an input device 30 and an output device 40. The processor 10, the memory 20, the input device 30, and the output device 40 may be connected through a bus or other means. Figure 5 Take the connection through the bus as an example.

[0117] The input device 30 can receive input digital or character information, and generate key signal inputs related to the user settings and function controls of the computer device, such as a touch screen, a keypad, a mouse, a trackpad, a touchpad, a pointing stick, one or more mouse buttons, a trackball, a joystick, etc. The output device 40 may include a display device, an auxiliary lighting device (e.g., an LED), and a haptic feedback device (e.g., a vibration motor), etc. The above display device includes, but is not limited to, a liquid crystal display, a light-emitting diode, a display, and a plasma display. In some alternative embodiments, the display device may be a touch screen.

[0118] The embodiment of the present invention also provides a computer-readable storage medium. The method according to the embodiment of the present invention can be implemented in hardware, firmware, or be implemented as computer code that can be recorded on a storage medium, or be implemented as computer code that is originally stored in a remote storage medium or a non-transitory machine-readable storage medium and downloaded through a network and will be stored in a local storage medium, so that the method described herein can be stored in such software processing on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only memory, a random access memory, a flash memory, a hard disk, or a solid-state drive, etc.; further, the storage medium can also include a combination of the above types of memories. It can be understood that a computer, a processor, a microprocessor controller, or programmable hardware includes a storage component that can store or receive software or computer code, and when the software or computer code is accessed and executed by the computer, the processor, or the hardware, the method shown in the above embodiment is implemented.

[0119] A part of the present invention can be applied as a computer program product, such as computer program instructions, which when executed by a computer, can call or provide the method and / or technical solution according to the present invention through the operation of the computer. Those skilled in the art should be able to understand that the forms of existence of computer program instructions in a computer-readable medium include, but are not limited to, source files, executable files, installation package files, etc. Correspondingly, the ways in which computer program instructions are executed by a computer include, but are not limited to: the computer directly executes the instruction, or the computer compiles the instruction and then executes the corresponding compiled program, or the computer reads and executes the instruction, or the computer reads and installs the instruction and then executes the corresponding installed program. Here, the computer-readable medium can be any available computer-readable storage medium or communication medium accessible by the computer.

[0120] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations fall within the scope of protection.

Claims

1. A method for protecting a high temperature gas-cooled reactor when the reactor loses external power supply, characterized in that: include: Detect the pressure difference of the emergency busbar inlet switch, main helium fan switch and main feed water orifice flowmeter of the high temperature gas-cooled reactor unit to determine whether the emergency busbar inlet switch trip signal, main helium fan trip signal and main feed water orifice reverse pressure difference signal are generated; Determine whether to generate a loss of off-site power supply protection signal based on the generation of the emergency busbar incoming line switch trip signal, the main helium blower trip signal and the main feedwater orifice reverse pressure difference signal; Based on the loss of external power protection signal, the high temperature gas-cooled reactor unit is controlled to execute a preset reactor shutdown standard action.

2. The method for protecting a high temperature gas-cooled reactor in the event of loss of external power supply according to claim 1, characterized in that: The determining whether to generate a loss of off-site power supply protection signal based on the generation of the emergency busbar incoming line switch trip signal, the main helium blower trip signal and the main feedwater orifice reverse pressure difference signal comprises: Performing logic analysis based on the generation of the emergency busbar incoming line switch trip signal, the main helium blower trip signal and the main feedwater orifice reverse pressure difference signal; If at least one of the main helium blower trip signal or the main feedwater orifice reverse pressure differential signal is generated simultaneously with the emergency busbar incoming switch trip signal, a power outage protection signal is generated.

3. The method for protecting a high temperature gas-cooled reactor in the event of loss of external power supply according to claim 1, characterized in that: The method of detecting the pressure difference of the emergency busbar inlet switch, the main helium fan switch and the main feed water orifice flowmeter of the high temperature gas-cooled reactor unit to determine whether a trip signal of the emergency busbar inlet switch, a trip signal of the main helium fan and a reverse pressure difference signal of the main feed water orifice is generated includes: Detecting the tripping signal of the pressure loss relay of the emergency bus incoming switch of the high temperature gas-cooled reactor unit, and generating the emergency bus incoming switch tripping signal when a first preset number or more of the pressure loss relays have tripping signals; Detecting a trip signal of a circuit breaker of a main helium blower of a high temperature gas-cooled reactor unit, and generating a main helium blower trip signal when a second preset number or more of circuit breakers have trip signals; The pressure difference of the main feed water orifice flow meter of the high temperature gas-cooled reactor unit is detected. When the value of the pressure difference of the main feed water orifice flow meter of the third preset number or more is less than zero, a main feed water orifice reverse pressure difference signal is generated.

4. The method for protecting a high temperature gas-cooled reactor in the event of loss of external power supply according to claim 3, characterized in that: The reactor shutdown standard action includes closing the main steam isolation valve after a delay of 30 seconds; Correspondingly, after controlling the high temperature gas-cooled reactor unit to execute the preset reactor shutdown standard action, it includes: After a first preset time interval, a signal for opening the main steam isolation valve is output; Detect the drop in main steam pressure. When the drop in main steam pressure exceeds the set pressure difference value, close the main steam isolation valve again. The set pressure difference value is 1Mpa-3Mpa.

5. The method for protecting a high temperature gas-cooled reactor in the event of loss of external power supply according to claim 4, characterized in that: The reactor shutdown standard actions also include controlling the safety rod and the regulating rod to fall, shutting down the main helium blower, closing the main helium blower damper, shutting down the main feed water pump and closing the main feed water isolation valve.

6. The method for protecting a high temperature gas-cooled reactor in the event of loss of external power supply according to claim 1, characterized in that: After controlling the high temperature gas-cooled reactor unit to execute the preset reactor shutdown standard action, it also includes: Control the main steam trap to close.

7. A reactor protection device for a high temperature gas-cooled reactor in the event of loss of external power supply, characterized in that: include: The initial signal detection module is used to detect the pressure difference of the emergency busbar incoming line switch, the main helium fan switch and the main feed water orifice flow meter of the high temperature gas-cooled reactor unit, and determine whether the emergency busbar incoming line switch trip signal, the main helium fan trip signal and the main feed water orifice reverse pressure difference signal are generated; A power failure signal generating module, used to determine whether to generate a power failure protection signal based on the generation of the emergency busbar incoming line switch trip signal, the main helium blower trip signal and the main water supply orifice reverse pressure difference signal; The action execution module is used to control the high temperature gas-cooled reactor unit to execute a preset reactor shutdown standard action based on the loss of external power protection signal.

8. A computer device, characterized in that: include: A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the reactor protection method for a high-temperature gas-cooled reactor in the condition of losing off-site power supply according to any one of claims 1 to 6 by executing the computer instructions.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a computer to execute the reactor protection method for a high-temperature gas-cooled reactor in the condition of loss of external power supply according to any one of claims 1 to 6.

10. A computer program product, characterized in that It includes computer instructions, and the computer instructions are used to enable a computer to execute the reactor protection method for a high-temperature gas-cooled reactor in the condition of losing external power supply as described in any one of claims 1 to 6.

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