Method and system for judging and processing interruption of test mode of emergency diesel generator of nuclear power plant

Abstract

The invention belongs to the technical field of nuclear power, and particularly relates to a nuclear power plant emergency diesel generator test mode pause judgment processing method and system, and the method comprises the steps: S1, judging whether an EDG circuit breaker tripping signal Z1 exists in an EDG test mode or not, and if yes, generating an EDG outlet circuit breaker tripping signal, and transmitting the EDG outlet circuit breaker tripping signal to an EDG circuit breaker; s2, judging whether an emergency start EDG exists in the EDG test mode or not and keeping an emergency mode operation signal Z2, if yes, generating an EDG emergency start signal, keeping an EDG emergency start mode, and sending the EDG emergency start signal to an EDG control system; s3, after the EDG circuit breaker receives the signal Z1 for tripping off the EDG circuit breaker, the EDG circuit breaker is triggered to perform tripping action; and S4, the EDG control system triggers the EDG emergency starting action after receiving the emergency starting EDG and keeping the emergency mode operation signal Z2, and starts the EDG and keeps the emergency mode operation. According to the invention, the EDG of the nuclear power plant can cope with sudden working conditions during a periodic test, the test is stopped in time and the emergency mode is switched, thereby effectively ensuring the safety of the nuclear power plant.

Description

Technical Field

[0001] The invention belongs to the technical field of nuclear power, and in particular relates to a method and system for determining the termination of a test mode of an emergency diesel generator in a nuclear power plant. Background Art

[0002] Under normal operating conditions, the power supply outside the plant (grid) supplies power to the main transformer and plant transformer through the 500kV switch station, providing the preferred power supply for plant power (A1 / A3 / A4 combined, B1 / B3 / B4 combined), and supplies power to the standby transformer (also called auxiliary transformer) through the 220kV switch station, providing an alternative power supply for plant power (A2 divided, B2 divided), and the automatic or manual switching of plant power (A1 and A2 switching, B1 and B2 switching) is realized through the standby power switching device. During the operation of the reactor, the main generator transmits electric energy to the grid in parallel with the main transformer through the GCB, and also provides the preferred power supply for plant power.

[0003] The plant power system is divided into two parts: non-safety level and safety level, and is also set up in two columns. The non-safety level power system consists of off-site power supply, 500 / 220kV switch station, main transformer / plant transformer / standby transformer, main generator, non-safety level busbar A / B, alternative AC power supply (AAC), etc. The safety level power system consists of safety level busbar A / B and emergency diesel generator sets (EDG-A, EDG-B). The two columns of the safety level power system are called channel A and channel B.

[0004] If the nuclear power plant loses the off-site power supply (tripping of the 500kV side of the main transformer) during power operation, the steam turbine generator set will first enter the island operation mode, and the steam turbine generator set will shed load and continue to operate with the plant power supply while maintaining the rated speed and rated voltage. If it can be stabilized, the reactor and the steam turbine generator set will not be shut down, which is called successful island operation. If the island operation is unsuccessful, the reactor will be shut down, the generator will trip (GCB trips open), the plant transformer will trip (A1 and B1 trips open), and the power supply switch will be started at the same time (A2 and B2 are closed). The plant power supply is supplied by the standby transformer to maintain the residual heat discharge after the reactor is shut down. If the power supply switch fails, all off-site power supplies will be lost, the non-safety-level busbar and the safety-level busbar will all lose power, and EDG-A and EDG-B will automatically start and supply power to the safety-level busbar A / B separately (A4 / A6 is separated and A5 is closed, B4 / B6 is separated and B5 is closed), and the residual heat discharge after the reactor is shut down will continue to be maintained. If all EDGs fail, all power sources inside and outside the plant will be lost, which is called SBO (Station Blackout) condition. At this time, manually start the alternate AC source (AAC) and select channel A (A4 / A5 split and A6 combined) or channel B (B4 / B5 split and B6 combined) to supply power to continue to maintain the residual heat removal and continuous cooling after the reactor shutdown.

[0005] If a main system water loss accident (safety injection) or high-high pressure in the containment (safety spray) occurs during power operation of a nuclear power plant, the plant will be shut down and the reactor will be started, and dedicated safety facilities (such as high-pressure safety injection pumps, containment spray pumps, etc.) will be started to inject water into the main system and cool and reduce the pressure of the containment. At the same time, EDG-A and EDG-B will automatically start in emergency mode and maintain rated speed and rated voltage for no-load operation (on standby). If the safety-level bus loses power at the same time, EDG-A and EDG-B will automatically start in emergency mode and supply power to their respective buses separately. In emergency mode, EDG automatically locks unimportant protections (such as engine overcurrent, high diesel engine lubricating oil temperature, high diesel engine cooling water temperature, etc.), and only important protections (such as generator differential protection, diesel engine overspeed protection, etc.) can be exported for tripping and shutdown.

[0006] According to GB / T 20485-2018RK, during the power operation of a nuclear power plant, an EDG load test should be performed once a month to confirm its load capacity, and the load power should reach 90%-100% of its rated power. This test is usually carried out in a grid-connected manner. The EDG test is started manually, the working mode is the test mode, and both the important and unimportant protections of the unit are tripped or shut down.

[0007] However, if an emergency occurs during the regular grid-connected load test of EDG, the test should be automatically terminated according to the relevant standards. However, the relevant standards do not fully and specifically stipulate the entry conditions for terminating the test and the state of the plant power supply system. At the same time, domestic nuclear power plant EDGs generally do not have a comprehensive and complete automatic termination test function.

[0008] In view of the shortcomings of relevant standards and EDG of nuclear power plants, it is urgent to develop a determination and processing method and system for the termination of EDG test mode of nuclear power plants, which can be used by EDG of nuclear power plants to respond to sudden conditions during regular tests, terminate the test in time and switch to emergency mode to ensure the safety of nuclear power plants. Summary of the invention

[0009] The purpose of the present invention is to provide a method and system for determining the termination of the test mode of an emergency diesel generator in a nuclear power plant, which can ensure that the EDG of a nuclear power plant can respond to sudden operating conditions during regular tests, terminate the test in time and switch to emergency mode, thereby effectively ensuring the safety of the nuclear power plant.

[0010] The technical solution to achieve the purpose of the present invention is:

[0011] A method for determining the termination of a test mode of an emergency diesel generator in a nuclear power plant, the method comprising the following steps:

[0012] S1, determine whether there is an EDG circuit breaker tripping signal Z1 in the EDG test mode, if yes, generate an EDG outlet circuit breaker tripping signal and send it to the EDG circuit breaker;

[0013] S2, determine whether there is an emergency start EDG and maintain emergency mode operation signal Z2 in EDG test mode, if yes, generate EDG emergency start signal and maintain EDG emergency start mode, and send it to EDG control system;

[0014] S3, EDG circuit breaker receives EDG circuit breaker tripping signal Z1 and triggers EDG circuit breaker tripping action;

[0015] S4. After receiving the emergency start EDG and maintain emergency mode operation signal Z2, the EDG control system triggers the EDG emergency start action, starts the EDG and maintains the emergency mode operation.

[0016] Determine whether there is a tripping EDG circuit breaker signal Z1 in EDG test mode. Including: determine whether there is an abnormal plant power supply signal Y1 in EDG grid-connected mode, and a safety emergency signal Y2 of EDG in grid-connected mode; if there is an abnormal plant power supply signal Y1 in EDG grid-connected mode, or a safety emergency signal Y2 of EDG in grid-connected mode, it is determined that there is a tripping EDG circuit breaker signal Z1 in EDG test mode.

[0017] Determine whether there is an emergency start EDG in EDG test mode and keep the emergency mode operation signal Z2. Including: determine whether there is an abnormal plant power supply signal Y1 and a safety emergency signal X7 in EDG grid-connected mode; if there is an abnormal plant power supply signal Y1 in EDG grid-connected mode, or a safety emergency signal X7, then determine that there is an emergency start EDG in EDG test mode and keep the emergency mode operation signal Z2.

[0018] Determine whether there is an abnormal power supply signal Y1 in the EDG grid-connected mode. Including: determining whether there is an abnormal EDG electrical quantity signal X4, an off-site power supply loss signal X5, and a plant transformer protection tripping action signal X6; if there is an abnormal EDG electrical quantity signal X4, or an off-site power supply loss signal X5, or a plant transformer protection tripping action signal X6, it is determined that there is an abnormal power supply signal Y1 in the EDG grid-connected mode.

[0019] Determine whether there is a safety emergency signal Y2 of EDG in grid-connected mode. Including: determine whether there is an EDG circuit breaker closing signal, a safety-level bus incoming circuit breaker closing signal, and a safety emergency signal X7; if there is an EDG circuit breaker closing signal, a safety-level bus incoming circuit breaker closing signal, and a safety emergency signal X7 at the same time, it is determined that there is a safety emergency signal Y2 of EDG in grid-connected mode.

[0020] Determine whether there is a safety emergency signal X7. Including: determine whether there is a safety injection signal or a safety spraying signal; if there is a safety injection signal or a safety spraying signal, it is determined that there is a safety emergency signal X7.

[0021] Determine whether there is an EDG electrical quantity abnormal signal X4. Including: determine whether there is an abnormal power increase signal X1, an abnormal voltage decrease signal X2, and an abnormal frequency decrease signal X3; if there is an abnormal power increase signal X1, an abnormal voltage decrease signal X2, and an abnormal frequency decrease signal X3 at the same time, it is determined that there is an EDG electrical quantity abnormal signal X4.

[0022] Determine whether there is an off-site power loss signal X5. Including: determine whether there is a main transformer high-voltage side trip signal or a plant transformer high-voltage side trip signal. If there is a main transformer high-voltage side trip signal or a plant transformer high-voltage side trip signal, and it is self-maintained within the short delay of t1, it is determined that there is an off-site power loss signal X5.

[0023] Determine whether there is a plant transformer protection tripping action signal X6. Including: determine whether there is a plant transformer protection tripping signal, if there is a plant transformer protection tripping signal, and it is self-maintained within the short delay time t1, then determine that there is a plant transformer protection tripping action signal X6.

[0024] Determine whether there is an abnormal power increase signal X1. Specifically: determine whether there is an EDG power surge signal (power change rate dP / dt is greater than the set value) or an EDG overpower signal (forward power P is greater than the set value). If there is an EDG power surge signal (power change rate dP / dt is greater than the set value) or an EDG overpower signal (forward power P is greater than the set value), it is determined that there is an abnormal EDG power increase signal X1.

[0025] Determine whether there is an abnormal voltage reduction signal X2. Specifically: determine whether there is an EDG voltage sudden drop signal (negative voltage change rate dU / dt is less than the set value) or an EDG voltage reduction signal (voltage U is less than the set value). If there is an EDG voltage sudden drop signal (negative voltage change rate dU / dt is less than the set value) or an EDG voltage reduction signal (voltage U is less than the set value), it is determined that there is an abnormal EDG voltage reduction signal X2.

[0026] Determine whether there is an abnormal frequency reduction signal X3. Specifically: determine whether there is an EDG frequency sudden drop signal (negative frequency change rate df / dt is less than the set value) or an EDG frequency reduction signal (frequency f is less than the set value). If there is an EDG frequency sudden drop signal (negative frequency change rate df / dt is less than the set value) or an EDG frequency reduction signal (frequency f is less than the set value), it is determined that there is an EDG frequency abnormal reduction signal X3.

[0027] A nuclear power plant emergency diesel generator test mode termination determination processing system, the system comprising:

[0028] The generator power judgment module A is used to receive the generator power change rate and the generator forward power in the EDG comprehensive protection device, and judge the power signal output by the generator according to the generator power change rate and the generator forward power. If it is judged that the power signal output by the generator is abnormally increased, the abnormal power increase signal X1 is output, and the abnormal power increase signal X1 is sent to the electrical quantity judgment module D;

[0029] The generator voltage judgment module B is used to receive the generator voltage change rate and the generator voltage in the EDG comprehensive protection device, and judge the voltage signal output by the generator according to the generator voltage change rate and the generator voltage. If it is judged that the voltage signal output by the generator is abnormally reduced, the abnormal voltage reduction signal X2 is output, and the abnormal voltage reduction signal X2 is sent to the electrical quantity judgment module D;

[0030] The generator frequency judgment module C is used to receive the generator frequency change rate and the generator frequency in the EDG comprehensive protection device, and judge the frequency signal output by the generator according to the generator frequency change rate and the generator frequency. If it is judged that the frequency signal output by the generator is abnormally reduced, the abnormal frequency reduction signal X3 is output, and the abnormal frequency reduction signal X3 is sent to the electrical quantity judgment module D;

[0031] The electrical quantity judgment module D is used to receive the power abnormal increase signal X1 sent by the generator power judgment module A, the voltage abnormal decrease signal X2 sent by the generator voltage judgment module B, and the frequency abnormal decrease signal X3 sent by the generator frequency judgment module C, output the EDG electrical quantity abnormal signal X4, and send the EDG electrical quantity abnormal signal X4 to the plant power supply judgment module G in the EDG grid-connected mode;

[0032] The first delay module E is used to receive the main transformer high-voltage side tripping signal or the plant transformer high-voltage side tripping signal, and self-hold within the short delay time t1, output the external power loss signal X5, and send the external power loss signal X5 to the plant power judgment module G in the EDG grid-connected mode;

[0033] The second delay module F is used to receive the plant transformer protection tripping signal, and self-hold within the short delay time t1, output the plant transformer protection tripping action signal X6, and send the plant transformer protection tripping action signal X6 to the plant power supply judgment module G in the EDG grid-connected mode;

[0034] The plant power supply judgment module G in the EDG grid-connected mode is used to receive the EDG electrical quantity abnormality signal X4 sent by the electrical quantity judgment module D, the off-site power supply loss signal X5 sent by the first delay module E, and the plant transformer protection tripping action signal X6 sent by the second delay module F, output the plant power supply abnormality signal Y1 in the EDG grid-connected mode, and send the plant power supply abnormality signal Y1 in the EDG grid-connected mode to the EDG circuit breaker control module K and the emergency start EDG control module R;

[0035] The safety emergency judgment module H is used to receive the safety injection signal and the safety spraying signal, output the safety emergency signal X7, and send the safety emergency signal X7 to the safety emergency judgment module J of EDG in the grid-connected mode and the emergency start EDG control module R;

[0036] The safety emergency judgment module J of EDG in the grid-connected mode is used to receive the EDG circuit breaker closing signal, the safety-level bus incoming circuit breaker closing signal, and the safety emergency signal X7 sent by the safety emergency judgment module H, output the EDG safety emergency signal Y2 in the grid-connected mode, and send the EDG safety emergency signal Y2 in the grid-connected mode to the EDG circuit breaker control module K;

[0037] The EDG circuit breaker control module K is used to receive the abnormal power supply signal Y1 of the EDG grid-connected mode sent by the power supply judgment module G of the EDG grid-connected mode, and the safety emergency signal Y2 of the EDG grid-connected mode sent by the safety emergency judgment module J of the EDG grid-connected mode, output the EDG circuit breaker tripping signal Z1, and send the EDG circuit breaker tripping signal Z1 to the EDG circuit breaker;

[0038] The emergency start EDG control module R is used to receive the EDG grid-connected mode plant power abnormality signal Y1 sent by the plant power judgment module G and the safety emergency signal X7 sent by the safety emergency judgment module H, output the emergency start EDG and maintain the emergency mode operation signal Z2, and send the emergency start EDG and maintain the emergency mode operation signal Z2 to the EDG control system.

[0039] The generator power judgment module A judges that the power signal output by the generator increases abnormally. Specifically, if there is an EDG power surge signal (power change rate dP / dt is greater than a set value) or an EDG overpower signal (forward power P is greater than a set value), it is judged that the EDG power increases abnormally.

[0040] The generator voltage judgment module B judges that the voltage signal output by the generator is abnormally reduced. Specifically, if there is an EDG voltage sudden drop signal (negative voltage change rate dU / dt is less than a set value), or an EDG voltage reduction signal (voltage U is less than a set value), it is judged that the EDG voltage is abnormally reduced.

[0041] The generator frequency judgment module C judges that the frequency signal output by the generator is abnormally reduced. Specifically, if there is an EDG frequency sudden drop signal (negative frequency change rate df / dt is less than a set value), or an EDG frequency reduction signal (frequency f is less than a set value), it is judged that the EDG frequency is abnormally reduced.

[0042] The beneficial technical effects of the present invention are:

[0043] 1. A method and system for determining the termination of the test mode of an emergency diesel generator in a nuclear power plant provided by the present invention provides a method for terminating the EDG test mode and switching it to the emergency mode, which can ensure that the EDG of a nuclear power plant can respond to sudden operating conditions during regular tests, terminate the test in time and switch to the emergency mode, thereby effectively ensuring the safety of the nuclear power plant.

[0044] 2. The method and system for determining the termination of the test mode of an emergency diesel generator in a nuclear power plant provided by the present invention make up for the deficiencies in the design of the current EDG operation mode of a nuclear power plant, and effectively enhance the power supply reliability of the nuclear power plant in the EDG test mode.

[0045] 3. The method and system for determining the termination of the test mode of an emergency diesel generator in a nuclear power plant provided by the present invention have strong applicability and can be widely applied to the operation of EDG in existing nuclear power plants in China.

[0046] 4. The method and system for determining the termination of the test mode of an emergency diesel generator in a nuclear power plant provided by the present invention are not only applicable to the emergency diesel generator (EDG) of an active pressurized water reactor nuclear power plant, but also to the standby diesel generator set (SDG) of a heavy water reactor nuclear power plant and a passive pressurized water reactor nuclear power plant. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 Main electrical connections for nuclear power units Figure 1 In this figure, the GCB is connected between the main transformer and the plant transformer, and the voltage between the GCB and the plant transformer is usually 20-27kV;

[0048] Figure 2 Main electrical connections for nuclear power units Figure 2 In this figure, GCB is connected to the high voltage side of the main transformer, and the voltage levels of GCB, main transformer and plant transformer are all 500kV;

[0049] Figure 3 The present invention provides a block diagram of a nuclear power plant emergency diesel generator test mode termination determination processing system. DETAILED DESCRIPTION

[0050] The present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0051] In a method and system for determining the termination of a test mode of an emergency diesel generator in a nuclear power plant provided by the present invention, an emergency condition during an EDG grid-connected load test is determined as follows: a main transformer high voltage side trips (e.g. Figure 1 As shown) / Plant transformer high voltage side tripping (as shown) Figure 2 As shown), plant transformer protection tripping, main system water loss accident (safety injection), containment pressure high-high (safety blowout). Among them, the main transformer high-voltage side tripping (such as Figure 1 As shown) / Plant transformer high voltage side tripping (as shown) Figure 2 As shown in the figure), the plant transformer protection tripping is signaled by the nuclear power plant electrical relay protection device, and the main system loss of water accident (safe injection) and containment pressure high-high (safe blowout) are signaled by the nuclear power plant instrumentation and control reactor protection device.

[0052] During the period of power operation of the nuclear power plant, when the EDG is regularly connected to the grid and loaded, if the above-mentioned emergency occurs, the EDG test will be terminated, the EDG will be disconnected from the safety-grade busbar and placed in emergency mode to maintain the rated speed and rated voltage operation state.

[0053] The present invention provides a method for determining the termination of a test mode of an emergency diesel generator in a nuclear power plant, comprising the following steps:

[0054] S1, determine whether there is an EDG circuit breaker tripping signal Z1 in the EDG test mode, if yes, generate an EDG outlet circuit breaker tripping signal and send it to the EDG circuit breaker;

[0055] S2, determine whether there is an emergency start EDG and maintain emergency mode operation signal Z2 in EDG test mode, if yes, generate EDG emergency start signal and maintain EDG emergency start mode, and send it to EDG control system;

[0056] S3, EDG circuit breaker receives EDG circuit breaker tripping signal Z1 and triggers EDG circuit breaker tripping action;

[0057] S4. After receiving the emergency start EDG and maintain emergency mode operation signal Z2, the EDG control system triggers the EDG emergency start action, starts the EDG and maintains the emergency mode operation.

[0058] Determine whether there is a tripping EDG circuit breaker signal Z1 in EDG test mode. Including: determine whether there is an abnormal plant power supply signal Y1 in EDG grid-connected mode, and a safety emergency signal Y2 of EDG in grid-connected mode; if there is an abnormal plant power supply signal Y1 in EDG grid-connected mode, or a safety emergency signal Y2 of EDG in grid-connected mode, it is determined that there is a tripping EDG circuit breaker signal Z1 in EDG test mode.

[0059] Determine whether there is an emergency start EDG in EDG test mode and keep the emergency mode operation signal Z2. Including: determine whether there is an abnormal plant power supply signal Y1 and a safety emergency signal X7 in EDG grid-connected mode; if there is an abnormal plant power supply signal Y1 in EDG grid-connected mode, or a safety emergency signal X7, then determine that there is an emergency start EDG in EDG test mode and keep the emergency mode operation signal Z2.

[0060] Determine whether there is an abnormal power supply signal Y1 in the EDG grid-connected mode. Including: determining whether there is an abnormal EDG electrical quantity signal X4, an off-site power supply loss signal X5, and a plant transformer protection tripping action signal X6; if there is an abnormal EDG electrical quantity signal X4, or an off-site power supply loss signal X5, or a plant transformer protection tripping action signal X6, it is determined that there is an abnormal power supply signal Y1 in the EDG grid-connected mode.

[0061] Determine whether there is a safety emergency signal Y2 of EDG in grid-connected mode. Including: determine whether there is an EDG circuit breaker closing signal, a safety-level bus incoming circuit breaker closing signal, and a safety emergency signal X7; if there is an EDG circuit breaker closing signal, a safety-level bus incoming circuit breaker closing signal, and a safety emergency signal X7 at the same time, it is determined that there is a safety emergency signal Y2 of EDG in grid-connected mode.

[0062] Determine whether there is a safety emergency signal X7. Including: determine whether there is a safety injection signal or a safety spraying signal; if there is a safety injection signal or a safety spraying signal, it is determined that there is a safety emergency signal X7.

[0063] Determine whether there is an EDG electrical quantity abnormal signal X4. Including: determine whether there is an abnormal power increase signal X1, an abnormal voltage decrease signal X2, and an abnormal frequency decrease signal X3; if there is an abnormal power increase signal X1, an abnormal voltage decrease signal X2, and an abnormal frequency decrease signal X3 at the same time, it is determined that there is an EDG electrical quantity abnormal signal X4.

[0064] Determine whether there is an off-site power loss signal X5. Including: determine whether there is a main transformer high-voltage side trip signal or a plant transformer high-voltage side trip signal. If there is a main transformer high-voltage side trip signal or a plant transformer high-voltage side trip signal, and it is self-maintained within the short delay of t1, it is determined that there is an off-site power loss signal X5.

[0065] Determine whether there is a plant transformer protection tripping action signal X6. Including: determine whether there is a plant transformer protection tripping signal, if there is a plant transformer protection tripping signal, and it is self-maintained within the short delay time t1, then determine that there is a plant transformer protection tripping action signal X6.

[0066] Determine whether there is an abnormal power increase signal X1. Specifically: determine whether there is an EDG power surge signal (power change rate dP / dt is greater than the set value) or an EDG overpower signal (forward power P is greater than the set value). If there is an EDG power surge signal (power change rate dP / dt is greater than the set value) or an EDG overpower signal (forward power P is greater than the set value), it is determined that there is an abnormal EDG power increase signal X1.

[0067] Determine whether there is an abnormal voltage reduction signal X2. Specifically: determine whether there is an EDG voltage sudden drop signal (negative voltage change rate dU / dt is less than the set value) or an EDG voltage reduction signal (voltage U is less than the set value). If there is an EDG voltage sudden drop signal (negative voltage change rate dU / dt is less than the set value) or an EDG voltage reduction signal (voltage U is less than the set value), it is determined that there is an abnormal EDG voltage reduction signal X2.

[0068] Determine whether there is an abnormal frequency reduction signal X3. Specifically: determine whether there is an EDG frequency sudden drop signal (negative frequency change rate df / dt is less than the set value) or an EDG frequency reduction signal (frequency f is less than the set value). If there is an EDG frequency sudden drop signal (negative frequency change rate df / dt is less than the set value) or an EDG frequency reduction signal (frequency f is less than the set value), it is determined that there is an EDG frequency abnormal reduction signal X3. Figure 3 As shown, the present invention provides a nuclear power plant emergency diesel generator test mode termination determination processing system, comprising:

[0069] The generator power judgment module A is used to receive the generator power change rate and the generator forward power in the EDG comprehensive protection device, and judge the power signal output by the generator according to the generator power change rate and the generator forward power. If it is judged that the power signal output by the generator is abnormally increased, the abnormal power increase signal X1 is output, and the abnormal power increase signal X1 is sent to the electrical quantity judgment module D;

[0070] The generator voltage judgment module B is used to receive the generator voltage change rate and the generator voltage in the EDG comprehensive protection device, and judge the voltage signal output by the generator according to the generator voltage change rate and the generator voltage. If it is judged that the voltage signal output by the generator is abnormally reduced, the abnormal voltage reduction signal X2 is output, and the abnormal voltage reduction signal X2 is sent to the electrical quantity judgment module D;

[0071] The generator frequency judgment module C is used to receive the generator frequency change rate and the generator frequency in the EDG comprehensive protection device, and judge the frequency signal output by the generator according to the generator frequency change rate and the generator frequency. If it is judged that the frequency signal output by the generator is abnormally reduced, the abnormal frequency reduction signal X3 is output, and the abnormal frequency reduction signal X3 is sent to the electrical quantity judgment module D;

[0072] The electrical quantity judgment module D is used to receive the power abnormal increase signal X1 sent by the generator power judgment module A, the voltage abnormal decrease signal X2 sent by the generator voltage judgment module B, and the frequency abnormal decrease signal X3 sent by the generator frequency judgment module C, output the EDG electrical quantity abnormal signal X4, and send the EDG electrical quantity abnormal signal X4 to the plant power supply judgment module G in the EDG grid-connected mode;

[0073] The first delay module E is used to receive the main transformer high-voltage side tripping signal or the plant transformer high-voltage side tripping signal, and self-hold within the short delay time t1, output the external power loss signal X5, and send the external power loss signal X5 to the plant power judgment module G in the EDG grid-connected mode;

[0074] The second delay module F is used to receive the plant transformer protection tripping signal, and self-hold within the short delay time t1, output the plant transformer protection tripping action signal X6, and send the plant transformer protection tripping action signal X6 to the plant power supply judgment module G in the EDG grid-connected mode;

[0075] The plant power supply judgment module G in the EDG grid-connected mode is used to receive the EDG electrical quantity abnormality signal X4 sent by the electrical quantity judgment module D, the off-site power supply loss signal X5 sent by the first delay module E, and the plant transformer protection tripping action signal X6 sent by the second delay module F, output the plant power supply abnormality signal Y1 in the EDG grid-connected mode, and send the plant power supply abnormality signal Y1 in the EDG grid-connected mode to the EDG circuit breaker control module K and the emergency start EDG control module R;

[0076] The safety emergency judgment module H is used to receive the safety injection signal and the safety spraying signal, output the safety emergency signal X7, and send the safety emergency signal X7 to the safety emergency judgment module J of EDG in the grid-connected mode and the emergency start EDG control module R;

[0077] The safety emergency judgment module J of EDG in the grid-connected mode is used to receive the EDG circuit breaker closing signal, the safety-level bus incoming circuit breaker closing signal, and the safety emergency signal X7 sent by the safety emergency judgment module H, output the EDG safety emergency signal Y2 in the grid-connected mode, and send the EDG safety emergency signal Y2 in the grid-connected mode to the EDG circuit breaker control module K;

[0078] The EDG circuit breaker control module K is used to receive the abnormal power supply signal Y1 of the EDG grid-connected mode sent by the power supply judgment module G of the EDG grid-connected mode, and the safety emergency signal Y2 of the EDG grid-connected mode sent by the safety emergency judgment module J of the EDG grid-connected mode, output the EDG circuit breaker tripping signal Z1, and send the EDG circuit breaker tripping signal Z1 to the EDG circuit breaker;

[0079] The emergency start EDG control module R is used to receive the EDG grid-connected mode plant power abnormality signal Y1 sent by the plant power judgment module G and the safety emergency signal X7 sent by the safety emergency judgment module H, output the emergency start EDG and maintain the emergency mode operation signal Z2, and send the emergency start EDG and maintain the emergency mode operation signal Z2 to the EDG control system.

[0080] Example 1

[0081] The present invention provides a method for determining the termination of a test mode of an emergency diesel generator in a nuclear power plant, which specifically comprises the following steps:

[0082] S1, determine whether there is an EDG circuit breaker tripping signal Z1 in the EDG test mode, if yes, generate an EDG outlet circuit breaker tripping signal and send it to the EDG circuit breaker;

[0083] S2, determine whether there is an emergency start EDG and maintain emergency mode operation signal Z2 in EDG test mode, if yes, generate EDG emergency start signal and maintain EDG emergency start mode, and send it to EDG control system;

[0084] S3, EDG circuit breaker receives EDG circuit breaker tripping signal Z1 and triggers EDG circuit breaker tripping action;

[0085] S4. After receiving the emergency start EDG and maintain emergency mode operation signal Z2, the EDG control system triggers the EDG emergency start action, starts the EDG and maintains the emergency mode operation.

[0086] Among them, it is determined whether there is a tripping EDG circuit breaker signal Z1 in the EDG test mode and whether there is an emergency start EDG and maintain emergency mode operation signal Z2 in the EDG test mode. Specifically including:

[0087] The generator power judgment module A is used to receive the generator power change rate and the generator forward power in the EDG comprehensive protection device, and judge the power signal output by the generator according to the generator power change rate and the generator forward power. If it is judged that the power signal output by the generator is abnormally increased, the abnormal power increase signal X1 is output, and the abnormal power increase signal X1 is sent to the electrical quantity judgment module D;

[0088] The generator voltage judgment module B is used to receive the generator voltage change rate and the generator voltage in the EDG comprehensive protection device, and judge the voltage signal output by the generator according to the generator voltage change rate and the generator voltage. If it is judged that the voltage signal output by the generator is abnormally reduced, the abnormal voltage reduction signal X2 is output, and the abnormal voltage reduction signal X2 is sent to the electrical quantity judgment module D;

[0089] The generator frequency judgment module C is used to receive the generator frequency change rate and the generator frequency in the EDG comprehensive protection device, and judge the frequency signal output by the generator according to the generator frequency change rate and the generator frequency. If it is judged that the frequency signal output by the generator is abnormally reduced, the abnormal frequency reduction signal X3 is output, and the abnormal frequency reduction signal X3 is sent to the electrical quantity judgment module D;

[0090] The electrical quantity judgment module D is used to receive the power abnormal increase signal X1 sent by the generator power judgment module A, the voltage abnormal decrease signal X2 sent by the generator voltage judgment module B, and the frequency abnormal decrease signal X3 sent by the generator frequency judgment module C, output the EDG electrical quantity abnormal signal X4, and send the EDG electrical quantity abnormal signal X4 to the plant power supply judgment module G in the EDG grid-connected mode;

[0091] The first delay module E is used to receive the main transformer high-voltage side tripping signal or the plant transformer high-voltage side tripping signal, and self-hold within the short delay time t1, output the external power loss signal X5, and send the external power loss signal X5 to the plant power judgment module G in the EDG grid-connected mode;

[0092] The second delay module F is used to receive the plant transformer protection tripping signal, and self-hold within the short delay time t1, output the plant transformer protection tripping action signal X6, and send the plant transformer protection tripping action signal X6 to the plant power supply judgment module G in the EDG grid-connected mode;

[0093] The plant power supply judgment module G in the EDG grid-connected mode is used to receive the EDG electrical quantity abnormality signal X4 sent by the electrical quantity judgment module D, the off-site power supply loss signal X5 sent by the first delay module E, and the plant transformer protection tripping action signal X6 sent by the second delay module F, output the plant power supply abnormality signal Y1 in the EDG grid-connected mode, and send the plant power supply abnormality signal Y1 in the EDG grid-connected mode to the EDG circuit breaker control module K and the emergency start EDG control module R;

[0094] The safety emergency judgment module H is used to receive the safety injection signal and the safety spraying signal, output the safety emergency signal X7, and send the safety emergency signal X7 to the safety emergency judgment module J of EDG in the grid-connected mode and the emergency start EDG control module R;

[0095] The safety emergency judgment module J of EDG in the grid-connected mode is used to receive the EDG circuit breaker closing signal, the safety-level bus incoming circuit breaker closing signal, and the safety emergency signal X7 sent by the safety emergency judgment module H, output the EDG safety emergency signal Y2 in the grid-connected mode, and send the EDG safety emergency signal Y2 in the grid-connected mode to the EDG circuit breaker control module K;

[0096] The EDG circuit breaker control module K is used to receive the abnormal power supply signal Y1 of the EDG grid-connected mode sent by the power supply judgment module G of the EDG grid-connected mode, and the safety emergency signal Y2 of the EDG grid-connected mode sent by the safety emergency judgment module J of the EDG grid-connected mode, output the EDG circuit breaker tripping signal Z1, and send the EDG circuit breaker tripping signal Z1 to the EDG circuit breaker;

[0097] The emergency start EDG control module R is used to receive the EDG grid-connected mode plant power abnormality signal Y1 sent by the plant power judgment module G and the safety emergency signal X7 sent by the safety emergency judgment module H, output the emergency start EDG and maintain the emergency mode operation signal Z2, and send the emergency start EDG and maintain the emergency mode operation signal Z2 to the EDG control system.

[0098] The above output signals: abnormal power increase signal X1, abnormal voltage reduction signal X2, abnormal frequency reduction signal X3, abnormal EDG electrical quantity signal X4, external power supply loss signal X5, plant transformer protection tripping action signal X6, safety emergency signal X7, plant power supply abnormality signal Y1 in EDG grid-connected mode, safety emergency signal Y2 in EDG grid-connected mode, EDG circuit breaker tripping signal Z1, EDG emergency start in EDG test mode and maintaining emergency mode operation signal Z2, are all switching signals.

[0099] Example 2

[0100] The present invention provides a nuclear power plant emergency diesel generator test mode termination judgment processing method, which is used for the nuclear power plant EDG to deal with sudden working conditions during regular tests, terminate the test in time and switch to the emergency mode to ensure the safety of the nuclear power plant.

[0101] After the EDG test is terminated, if the safety-level bus loses power, according to the method of the present invention, the EDG automatically starts in emergency mode (it is already operating in emergency mode with rated speed and rated voltage), and at the same time, the reactor protection sends a load sweep signal to trip the safety-level bus incoming line and load circuit breaker, and delays for 10 seconds (waiting time for EDG to start successfully) to confirm that the EDG has started successfully, and then automatically closes the EDG circuit breaker, and automatically loads the emergency load to be started according to the set program.

[0102] The present invention is described in detail above in conjunction with the accompanying drawings and embodiments, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of ordinary technicians in the field without departing from the purpose of the present invention. Contents not described in detail in the present invention are all within the scope of the claims of the present invention.

Claims

1. A method for determining the termination of a test mode of an emergency diesel generator in a nuclear power plant, characterized in that: The method comprises the following steps: S1, determine whether there is an EDG circuit breaker tripping signal Z1 in the EDG test mode, if yes, generate an EDG outlet circuit breaker tripping signal and send it to the EDG circuit breaker; S2, determine whether there is an emergency start EDG and maintain emergency mode operation signal Z2 in EDG test mode, if yes, generate EDG emergency start signal and maintain EDG emergency start mode, and send it to EDG control system; S3, EDG circuit breaker receives EDG circuit breaker tripping signal Z1 and triggers EDG circuit breaker tripping action; S4. After receiving the emergency start EDG and maintain emergency mode operation signal Z2, the EDG control system triggers the EDG emergency start action, starts the EDG and maintains the emergency mode operation.

2. A method for determining the termination of a test mode of an emergency diesel generator in a nuclear power plant according to claim 1, characterized in that: Determining whether there is an EDG circuit breaker tripping signal Z1 in the EDG test mode includes: determining whether there is an abnormal plant power supply signal Y1 in the EDG grid-connected mode and a safety emergency signal Y2 of the EDG in the grid-connected mode; if there is an abnormal plant power supply signal Y1 in the EDG grid-connected mode, or there is a safety emergency signal Y2 of the EDG in the grid-connected mode, then it is determined that there is an EDG circuit breaker tripping signal Z1 in the EDG test mode.

3. A method for determining the termination of a test mode of an emergency diesel generator in a nuclear power plant according to claim 1, characterized in that: Determine whether there is an emergency start-up EDG in EDG test mode and maintain the emergency mode operation signal Z2, including: determine whether there is an abnormal plant power supply signal Y1 and a safety emergency signal X7 in EDG grid-connected mode; if there is an abnormal plant power supply signal Y1 in EDG grid-connected mode, or there is a safety emergency signal X7, then determine that there is an emergency start-up EDG in EDG test mode and maintain the emergency mode operation signal Z2.

4. A method for determining the termination of a test mode of an emergency diesel generator in a nuclear power plant according to claim 2 or 3, characterized in that: Determining whether there is an abnormal plant power supply signal Y1 in the EDG grid-connected mode includes: determining whether there is an abnormal EDG electrical quantity signal X4, an off-site power supply loss signal X5, and a plant transformer protection tripping action signal X6; if there is an abnormal EDG electrical quantity signal X4, or an off-site power supply loss signal X5, or a plant transformer protection tripping action signal X6, then it is determined that there is an abnormal plant power supply signal Y1 in the EDG grid-connected mode.

5. A method for determining the termination of a test mode of an emergency diesel generator in a nuclear power plant according to claim 2, characterized in that: Determining whether there is a safety emergency signal Y2 of EDG in grid-connected mode includes: determining whether there is an EDG circuit breaker closing signal, a safety-level bus incoming circuit breaker closing signal, and a safety emergency signal X7; if there are an EDG circuit breaker closing signal, a safety-level bus incoming circuit breaker closing signal, and a safety emergency signal X7 at the same time, it is determined that there is a safety emergency signal Y2 of EDG in grid-connected mode.

6. A method for determining the termination of a test mode of an emergency diesel generator in a nuclear power plant according to claim 5, characterized in that: Determining whether there is a safety emergency signal X7 includes: determining whether there is a safety injection signal or a safety spraying signal; if there is a safety injection signal or a safety spraying signal, it is determined that there is a safety emergency signal X7.

7. A method for determining the termination of a test mode of an emergency diesel generator in a nuclear power plant according to claim 4, characterized in that: Determining whether there is an EDG electrical quantity abnormal signal X4 includes: determining whether there is an abnormal power increase signal X1, an abnormal voltage decrease signal X2, and an abnormal frequency decrease signal X3; if there is an abnormal power increase signal X1, an abnormal voltage decrease signal X2, and an abnormal frequency decrease signal X3 at the same time, it is determined that there is an EDG electrical quantity abnormal signal X4.

8. A method for determining the termination of a test mode of an emergency diesel generator in a nuclear power plant according to claim 4, characterized in that: Determine whether there is an off-site power loss signal X5, including: determine whether there is a main transformer high-voltage side trip signal or a plant transformer high-voltage side trip signal. If there is a main transformer high-voltage side trip signal or a plant transformer high-voltage side trip signal, and it is self-maintained within the short delay time t1, it is determined that there is an off-site power loss signal X5.

9. A method for determining the termination of a test mode of an emergency diesel generator in a nuclear power plant according to claim 4, characterized in that: Determining whether there is a plant transformer protection tripping action signal X6 includes: determining whether there is a plant transformer protection tripping signal. If there is a plant transformer protection tripping signal and it is self-maintained within the short delay time t1, it is determined that there is a plant transformer protection tripping action signal X6.

10. A method for determining the termination of a test mode of an emergency diesel generator in a nuclear power plant according to claim 7, characterized in that: Determine whether there is an abnormal power increase signal X1, specifically: determine whether there is an EDG power sudden increase signal or an EDG over-power signal. If there is an EDG power sudden increase signal or an EDG over-power signal, it is determined that there is an abnormal EDG power increase signal X1.

11. A method for determining the termination of a test mode of an emergency diesel generator in a nuclear power plant according to claim 7, characterized in that: Determining whether there is an abnormal voltage reduction signal X2 specifically includes: determining whether there is an EDG voltage sudden drop signal or an EDG voltage reduction signal. If there is an EDG voltage sudden drop signal or an EDG voltage reduction signal, it is determined that there is an abnormal EDG voltage reduction signal X2.

12. A method for determining the termination of a test mode of an emergency diesel generator in a nuclear power plant according to claim 7, characterized in that: Determine whether there is an abnormal frequency reduction signal X3, specifically: determine whether there is an EDG frequency sudden drop signal or an EDG frequency reduction signal. If there is an EDG frequency sudden drop signal or an EDG frequency reduction signal, it is determined that there is an EDG frequency abnormal reduction signal X3.

13. A nuclear power plant emergency diesel generator test mode termination judgment processing system, characterized in that: The system comprises: The generator power judgment module A is used to receive the generator power change rate and the generator forward power in the EDG comprehensive protection device, and judge the power signal output by the generator according to the generator power change rate and the generator forward power. If it is judged that the power signal output by the generator is abnormally increased, the abnormal power increase signal X1 is output, and the abnormal power increase signal X1 is sent to the electrical quantity judgment module D; The generator voltage judgment module B is used to receive the generator voltage change rate and the generator voltage in the EDG comprehensive protection device, and judge the voltage signal output by the generator according to the generator voltage change rate and the generator voltage. If it is judged that the voltage signal output by the generator is abnormally reduced, the abnormal voltage reduction signal X2 is output, and the abnormal voltage reduction signal X2 is sent to the electrical quantity judgment module D; The generator frequency judgment module C is used to receive the generator frequency change rate and the generator frequency in the EDG comprehensive protection device, and judge the frequency signal output by the generator according to the generator frequency change rate and the generator frequency. If it is judged that the frequency signal output by the generator is abnormally reduced, the abnormal frequency reduction signal X3 is output, and the abnormal frequency reduction signal X3 is sent to the electrical quantity judgment module D; The electrical quantity judgment module D is used to receive the power abnormal increase signal X1 sent by the generator power judgment module A, the voltage abnormal decrease signal X2 sent by the generator voltage judgment module B, and the frequency abnormal decrease signal X3 sent by the generator frequency judgment module C, output the EDG electrical quantity abnormal signal X4, and send the EDG electrical quantity abnormal signal X4 to the plant power supply judgment module G in the EDG grid-connected mode; The first delay module E is used to receive the main transformer high-voltage side tripping signal or the plant transformer high-voltage side tripping signal, and self-hold within the short delay time t1, output the external power loss signal X5, and send the external power loss signal X5 to the plant power judgment module G in the EDG grid-connected mode; The second delay module F is used to receive the plant transformer protection tripping signal, and self-hold within the short delay time t1, output the plant transformer protection tripping action signal X6, and send the plant transformer protection tripping action signal X6 to the plant power supply judgment module G in the EDG grid-connected mode; The plant power supply judgment module G in the EDG grid-connected mode is used to receive the EDG electrical quantity abnormality signal X4 sent by the electrical quantity judgment module D, the off-site power supply loss signal X5 sent by the first delay module E, and the plant transformer protection tripping action signal X6 sent by the second delay module F, output the plant power supply abnormality signal Y1 in the EDG grid-connected mode, and send the plant power supply abnormality signal Y1 in the EDG grid-connected mode to the EDG circuit breaker control module K and the emergency start EDG control module R; The safety emergency judgment module H is used to receive the safety injection signal and the safety spraying signal, output the safety emergency signal X7, and send the safety emergency signal X7 to the safety emergency judgment module J of EDG in the grid-connected mode and the emergency start EDG control module R; The safety emergency judgment module J of EDG in the grid-connected mode is used to receive the EDG circuit breaker closing signal, the safety-level bus incoming circuit breaker closing signal, and the safety emergency signal X7 sent by the safety emergency judgment module H, output the EDG safety emergency signal Y2 in the grid-connected mode, and send the EDG safety emergency signal Y2 in the grid-connected mode to the EDG circuit breaker control module K; The EDG circuit breaker control module K is used to receive the abnormal power supply signal Y1 of the EDG grid-connected mode sent by the power supply judgment module G of the EDG grid-connected mode, and the safety emergency signal Y2 of the EDG grid-connected mode sent by the safety emergency judgment module J of the EDG grid-connected mode, output the EDG circuit breaker tripping signal Z1, and send the EDG circuit breaker tripping signal Z1 to the EDG circuit breaker; The emergency start EDG control module R is used to receive the EDG grid-connected mode plant power abnormality signal Y1 sent by the plant power judgment module G and the safety emergency signal X7 sent by the safety emergency judgment module H, output the emergency start EDG and maintain the emergency mode operation signal Z2, and send the emergency start EDG and maintain the emergency mode operation signal Z2 to the EDG control system.

14. A nuclear power plant emergency diesel generator test mode termination determination processing system according to claim 13, characterized in that: The generator power judgment module A judges that the power signal output by the generator increases abnormally. Specifically, if there is an EDG power surge signal or an EDG overpower signal, it is judged that the EDG power increases abnormally.

15. A nuclear power plant emergency diesel generator test mode termination determination processing system according to claim 13, characterized in that: The generator voltage judgment module B judges that the voltage signal output by the generator is abnormally reduced. Specifically, if there is an EDG voltage sudden drop signal or an EDG voltage reduction signal, it is judged that the EDG voltage is abnormally reduced.

16. A nuclear power plant emergency diesel generator test mode termination determination processing system according to claim 13, characterized in that: The generator frequency judgment module C judges that the frequency signal output by the generator is abnormally reduced. Specifically, if there is an EDG frequency sudden drop signal or an EDG frequency reduction signal, it is judged that the EDG frequency is abnormally reduced.

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