Discharge test method and device for nuclear power station storage battery

Abstract

The invention relates to a discharge test method and device for a storage battery of a nuclear power station. The discharge test method comprises the following steps: executing test preparation work before a discharge test of a storage battery pack; after the test preparation work is completed, determining discharge test parameters; the discharge test parameters comprise target discharge time and target discharge current; executing a discharge test of the storage battery pack according to the target discharge time and the target discharge current; in the discharge test process, test parameters of the storage battery pack are monitored in real time, and real-time discharge parameters are obtained; and performing quality evaluation on the storage battery pack according to the real-time discharge parameters. By adjusting and setting the discharge time and the discharge current, the discharge test current is reduced, the capacity requirement of the discharge loop equipment is reduced, the fire risk is reduced, the discharge test duration is shortened, the key path of unit overhaul cannot be prolonged in the storage battery discharge test of the nuclear power station, and the generating capacity of the nuclear power station is effectively ensured.

Description

Technical Field

[0001] This invention relates to the field of testing nuclear power plant batteries, and more specifically, to a method and apparatus for discharging nuclear power plant batteries. Background Technology

[0002] The DC system batteries in nuclear power plants are the last emergency power source after the loss of AC power. The batteries are designed to discharge for 1 hour, meaning that after the loss of AC power, the batteries can supply power to downstream loads for at least 1 hour. Batteries are crucial for emergency response after nuclear power plant accidents. During the overhaul of each unit, the batteries need to be discharged to verify their ability to supply power to downstream loads for 1 hour under emergency conditions.

[0003] Currently, the periodic discharge tests of the DC system batteries in nuclear power plants are mainly conducted using the following two methods: Method 1: Conduct an operational test by discharging for 1 hour at the downstream maximum load current Id. Method 2: Conduct a performance test by discharging for 10 hours at the battery's rated 10-hour discharge rate (I10).

[0004] As nuclear power plants become increasingly digitized, the DC load required by control systems such as DCS is gradually increasing, with downstream loads approaching 1000A. If Method 1 is used for discharge testing, the configuration parameters of discharge circuit equipment, such as discharge switchgear, cable selection, and mobile discharge trolley devices, are demanding, occupying significant plant space and generating substantial heat during discharge, posing a fire hazard. If Method 2 is used, the discharge current is smaller, but the formal discharge test lasts for 10 hours. Every hour, data such as voltage and electrolyte specific gravity need to be recorded. Adding the preparation time and post-test cleanup, the continuous on-site working time exceeds 12 hours, resulting in a heavy workload for on-site personnel. Furthermore, Method 2 prolongs the nuclear power plant's overhaul time, reducing its power generation. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a discharge test method and apparatus for nuclear power plant batteries, addressing the problems existing in the prior art.

[0006] The technical solution adopted by this invention to solve its technical problem is: to construct a discharge test method for a nuclear power plant battery, comprising the following steps: Preparations for conducting a discharge test on the battery pack; After completing the test preparation work, determine the discharge test parameters; the discharge test parameters include: target discharge time and target discharge current; Perform a discharge test on the battery pack according to the target discharge time and target discharge current; During the discharge test, the test parameters of the battery pack are monitored in real time to obtain the real-time discharge parameters; The battery pack is evaluated for quality based on the real-time discharge parameters.

[0007] In the discharge test method for nuclear power plant batteries described in this invention, determining the discharge test parameters includes: Obtain the factory data of the battery pack; The target discharge time, plate aging rate, initial fully charged battery pack terminal voltage, final fully charged battery pack terminal voltage, and discharge cutoff voltage are determined based on the factory data of the battery pack. Determine the corresponding discharge test current based on the target discharge time; The target discharge current is obtained by calculating based on the discharge test current, the plate aging rate, the terminal voltage of the fully charged battery pack at the beginning of its service life, the terminal voltage of the fully charged battery pack at the end of its service life, and the discharge cutoff voltage.

[0008] In the discharge test method for nuclear power plant batteries according to the present invention, the step of calculating the target discharge current based on the discharge test current, the plate aging rate, the terminal voltage of the fully charged battery pack at the beginning of its service life, the terminal voltage of the fully charged battery pack at the end of its service life, and the discharge cutoff voltage includes: The terminal voltage influence rate is calculated based on the terminal voltage of the fully charged battery pack at the beginning of its service life, the terminal voltage of the fully charged battery pack at the end of its service life, and the discharge cutoff voltage. The target discharge current is obtained by calculating based on the terminal voltage influence rate, the plate aging rate, and the discharge test current.

[0009] In the discharge test method for nuclear power plant batteries described in this invention, the target discharge current is calculated using the following formula: =A A = Lr(A) × [Lr(A) - Lr(U)]; Where Lr(A) is the plate aging rate; Lr(U) is the terminal voltage influence rate, Lr(U)=(U0-U1) / (U0-1.8), U0 is the terminal voltage of the fully charged battery pack at the beginning of its service life, U1 is the terminal voltage of the fully charged battery pack at the end of its service life, and 1.8 is the discharge cutoff voltage.

[0010] In the discharge test method for nuclear power plant batteries described in this invention, the real-time discharge parameters include: the real-time discharge voltage of a single cell. The quality assessment of the battery pack based on the real-time discharge parameters includes: The average voltage of a single battery cell is obtained by averaging the real-time discharge voltage of the single battery cell. The minimum voltage of a single battery cell is obtained by filtering based on its real-time discharge voltage. The quality of the battery pack is assessed based on the average voltage and the minimum voltage of each individual cell.

[0011] In the discharge test method for nuclear power plant batteries according to the present invention, the quality assessment of the battery pack based on the average voltage and the minimum voltage of the individual cells includes: Determine whether the average voltage and the minimum voltage of the single cell are both greater than a set value. If so, continue discharging until the target discharge time is reached, and determine that the battery pack is in good condition. If the average voltage of a single battery cell or the minimum voltage of a single battery cell is less than the set value, and the real-time discharge time is less than the target discharge time, then the discharge test is stopped, and the battery pack is deemed unqualified.

[0012] In the discharge test method for nuclear power plant batteries described in this invention, the method further includes: Obtain the real-time discharge time and actual discharge capacity of the battery pack; Determine whether the real-time discharge time of the battery pack has reached the minimum required discharge time, and whether the real-time discharge capacity is greater than or equal to the theoretical discharge capacity. If so, then stop the discharge test.

[0013] In the discharge test method for nuclear power plant batteries described in this invention, the method further includes: Obtain the real-time discharge time and actual discharge capacity of the battery pack at the current temperature; Determine whether the real-time discharge time of the battery pack at the current temperature is greater than or equal to 0.8 times the theoretical reserve time, and whether the actual discharge capacity is greater than or equal to 0.8 times the theoretical discharge capacity; If so, then stop the discharge test.

[0014] In the discharge test method for nuclear power plant batteries described in this invention, the test preparation work before performing the discharge test of the battery pack includes: Perform a discharge test environment inspection; Perform a visual inspection of the battery pack; Measure basic data before the battery pack discharge test.

[0015] The present invention also provides a discharge test apparatus for nuclear power plant batteries, comprising: The pre-test preparation unit is used to perform pre-test preparation work before the discharge test of the battery pack. The test parameter determination unit is used to determine the discharge test parameters after the test preparation work is completed; the discharge test parameters include: target discharge time and target discharge current; A discharge test execution unit is used to perform a discharge test on the battery pack according to the target discharge time and target discharge current. The discharge parameter monitoring unit is used to monitor the test parameters of the battery pack in real time during the discharge test and obtain the real-time discharge parameters. A battery quality assessment unit is used to assess the quality of the battery pack based on the real-time discharge parameters.

[0016] The discharge test method and apparatus for nuclear power plant batteries of the present invention have the following beneficial effects: The method includes the following steps: performing test preparation work before the discharge test of the battery pack; determining the discharge test parameters after completing the test preparation work; the discharge test parameters include: target discharge time and target discharge current; performing the discharge test of the battery pack according to the target discharge time and target discharge current; during the discharge test, monitoring the test parameters of the battery pack in real time to obtain real-time discharge parameters; and conducting a quality assessment of the battery pack based on the real-time discharge parameters. By adjusting the discharge time and discharge current, the present invention reduces the discharge test current, reduces the capacity requirements of the discharge circuit equipment, reduces the fire risk, and reduces the duration of the discharge test, thus preventing the nuclear power plant battery discharge test from extending the critical path of unit overhaul and effectively ensuring the power generation of the nuclear power plant. Attached Figure Description

[0017] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings: Figure 1 This is a schematic flowchart of the discharge test method for nuclear power plant batteries provided in an embodiment of the present invention; Figure 2 This is a logic block diagram of the discharge test device for nuclear power plant batteries provided in an embodiment of the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] To address the problems existing in the current discharge test methods used for nuclear power plant batteries, this invention provides a discharge test method for nuclear power plant batteries. This discharge test method modifies the discharge test time and discharge test current, thereby reducing the discharge test current, reducing the capacity requirements of the discharge circuit equipment, reducing the fire risk, and reducing the duration of the discharge test. This ensures that the battery discharge test does not prolong the critical path of unit overhaul and does not affect the unit's power generation.

[0020] The "Regular Testing and Supervision Outline for Safety-Related Systems and Equipment in Nuclear Power Plant Units" requires verification that the battery pack capacity of the DC power supply system LBA is ≥80% of the manufacturer's rated value: Battery pack capacity ≥80% of manufacturer's rated value (54 months; 36 months when the battery pack reaches 85% of its expected lifespan and capacity ≥100% of the manufacturer's rated value; 18 months when the battery pack shows signs of aging, or reaches 85% of its expected lifespan and capacity <100% of the manufacturer's rated value). A discharge test is conducted at the required discharge current value to verify that the LBA battery pack discharge time and battery pack terminal voltage meet the requirements: Discharge time meets requirements; final battery voltage ≥108V; voltage of each battery cell ≥1.80V. (18-month cycle) Battery discharge begins: LBA008KA: Correct trigger voltage low; LBA002KA\AA: Correct trigger. If the above test fails or the inspection results are unqualified, the executor must immediately report to the shift leader and project manager. Reference Figure 1 In one embodiment, the discharge test method for the nuclear power plant battery includes the following steps: Step S10: Perform test preparation work before the discharge test of the battery pack.

[0021] Optionally, in this embodiment of the invention, the test preparation work before performing the discharge test of the battery pack includes: performing a discharge test environment check; performing a battery pack appearance check; and measuring the basic data of the battery pack before the discharge test.

[0022] Specifically, the discharge test environment inspection includes: checking that the charger 380VAC incoming circuit breaker LKE304 is closed and the outgoing circuit breaker LBA003JA is closed; checking that the charger 380VAC AC circuit breaker LLA202 is closed and the outgoing circuit breaker LBA004JA is closed; checking that PFM118JA in the LBA002RD diesel engine application power supply PFM102CR is disconnected and isolated; checking that the battery outgoing circuit breaker LBA005JA is closed; checking that the battery pack discharge test outgoing circuit breaker LBA006JA is in the open position; placing the battery discharge test vehicle near LYS007CR, setting up the work area, and hanging signs and warning tapes; checking that the battery room ventilation system is operating normally; measuring the battery room temperature and recording it in the attached table.

[0023] The specific visual inspection of the battery pack includes: no signs of overheating; and no cracks or damage to battery accessories (anti-acid plugs, level indicators, etc.).

[0024] The basic data to be measured before the battery pack discharge test includes: measuring the float charge voltage and float charge current of the battery pack and recording them in the attached table; measuring the terminal voltage of each battery cell and recording it in the attached table; measuring the battery specific gravity: selecting five batteries with low voltage as monitoring batteries, measuring the electrolyte temperature of these five batteries, calculating the current average temperature θ based on this, and recording it in the table; calculating the standard electrolyte specific gravity at the current average temperature according to the following formula and recording it in the report page: d(θ)= d(20℃)-0.0007 d(θ-20℃); d(20℃)=1.24±0.01g / m 3 ; Measure and record the specific gravity of the electrolyte in each battery cell; compare the specific gravity of the battery electrolyte with the calculated standard electrolyte value d(θ) at the current average temperature; if it is not qualified, adjust the specific gravity; record the test results in the maintenance report and confirm that each parameter is qualified. Test the discharge test circuit, which must meet the following requirements: use a megohmmeter at the 500V range to measure the insulation between the positive and negative terminals and to ground of the LYS circuit, and record the results in the attached table; use a megohmmeter at the 100V range to measure the insulation between the positive and negative grounding wires of the discharge trolley and record the results in the attached table. Verify that the LYS007CR switch is in the open position; connect the discharge trolley cable to the LYS007CR, ensure the polarity connection is correct, and preheat the discharge trolley; connect the battery discharge recorder and clamp meter to the battery terminals and circuit, confirm that the wiring is reliable, the battery measurement lines of each section are securely fixed, and the instrument display is normal.

[0025] Step S20: After completing the test preparation work, determine the discharge test parameters; the discharge test parameters include: target discharge time and target discharge current.

[0026] Optionally, in this embodiment of the invention, determining the discharge test parameters includes: acquiring the factory data of the battery pack; determining the target discharge time, plate aging rate, initial fully charged battery pack terminal voltage at the beginning of its lifespan, final fully charged battery pack terminal voltage at the end of its lifespan, and discharge cutoff voltage based on the factory data of the battery pack; determining the corresponding discharge test current based on the target discharge time; and calculating the target discharge current based on the discharge test current, plate aging rate, initial fully charged battery pack terminal voltage at the beginning of its lifespan, final fully charged battery pack terminal voltage at the end of its lifespan, and discharge cutoff voltage. Specifically, calculating the target discharge current based on the discharge test current, plate aging rate, initial fully charged battery pack terminal voltage at the beginning of its lifespan, final fully charged battery pack terminal voltage at the end of its lifespan, and discharge cutoff voltage includes: calculating the terminal voltage influence rate based on the initial fully charged battery pack terminal voltage at the beginning of its lifespan, final fully charged battery pack terminal voltage at the end of its lifespan, and discharge cutoff voltage; and calculating the target discharge current based on the terminal voltage influence rate, plate aging rate, and discharge test current.

[0027] Preferably, the target discharge current is calculated using the following formula: =A A = Lr(A) × [Lr(A) - Lr(U)]; Where Lr(A) is the plate aging rate; Lr(U) is the terminal voltage influence rate, Lr(U)=(U0-U1) / (U0-1.8), U0 is the terminal voltage of the fully charged battery pack at the beginning of its service life, U1 is the terminal voltage of the fully charged battery pack at the end of its service life, and 1.8 is the discharge cutoff voltage.

[0028] Preferably, in this embodiment of the invention, the target discharge time is 3 hours or 5 hours. Taking a 3-hour discharge test as an example, the target discharge current can be calculated from the discharge current (i.e., the discharge test current) that can be continuously discharged at different discharge times at the beginning of the battery's life, provided by the battery manufacturer. The discharge currents that can be continuously discharged at different discharge times at the beginning of the battery's life are shown in the table below: As shown in the table above, the discharge test current for 3 hours is I 3. As the battery ages, the [problem] gradually increases. I 10 / I 3. Calculate the standard 3-hour discharge value at the end of the battery's lifespan (when the discharge capacity reaches 80% of the initial capacity after 10 hours). . =A× I 3 (Since the effects of battery aging on 3-hour and 10-hour discharges are different, A≠1), A=Lr(A) ×[Lr(A)-Lr(U)], and the parameters in the formula are defined as follows: Lr(U) = (U0 - U1) / (U0 - 1.8) represents the terminal voltage influence rate, Lr(A) = 0.8 represents the plate aging rate, U0 is the terminal voltage of a fully charged battery at the beginning of its lifespan, U1 is the terminal voltage of a fully charged battery at the end of its lifespan, and 1.8 is the discharge cutoff voltage. This is the target discharge current.

[0029] Step S30: Perform a discharge test on the battery pack according to the target discharge time and target discharge current.

[0030] After determining the target discharge current, the discharge test can be arranged. Specifically: First, notify the main control; then, disconnect the 380VAC incoming circuit breaker LKE304 of charger LBA001RD; open the cabinet door of LBA002RD and confirm that terminals #1 and #2 of X12 of 001BN at the bottom of LBA002RD cabinet are short-circuited; switch charger LBA002RD to equalization charging mode; confirm that the charger is in equalization charging state; measure the equalization charging voltage from the battery pack terminals and record the data in the attached table.

[0031] Monitor the terminal voltage of the battery pack; the voltage and temperature of the monitored battery, etc.

[0032] Step S40: During the discharge test, the test parameters of the battery pack are monitored in real time to obtain the real-time discharge parameters.

[0033] Step S50: Evaluate the quality of the battery pack based on real-time discharge parameters.

[0034] Optionally, in this embodiment of the invention, the real-time discharge parameters include: the real-time discharge voltage of a single cell; the quality assessment of the battery pack based on the real-time discharge parameters includes: calculating the average voltage of a single cell based on the average real-time discharge voltage of the single cell; filtering based on the real-time discharge voltage of the single cell to obtain the minimum voltage of a single cell; and assessing the quality of the battery pack based on the average voltage and the minimum voltage of a single cell. Specifically, assessing the quality of the battery pack based on the average voltage and the minimum voltage of a single cell includes: determining whether both the average voltage and the minimum voltage of a single cell are greater than a set value; if so, continuing discharge until the target discharge time is reached, and determining that the battery pack is qualified; if the average voltage or the minimum voltage of a single cell is less than the set value, and the real-time discharge time is less than the target discharge time, stopping the discharge test, and determining that the battery pack is unqualified. Preferably, the set value is 1.8V.

[0035] Furthermore, the discharge test method for the nuclear power plant's batteries also includes: obtaining the real-time discharge time and actual discharge capacity of the battery pack; determining whether the real-time discharge time of the battery pack has reached the minimum discharge time (td) and whether the real-time discharge capacity is greater than or equal to the theoretical discharge capacity; if so, the discharge test is stopped.

[0036] Furthermore, the discharge test method for the nuclear power plant's batteries also includes: obtaining the real-time discharge time and actual discharge capacity of the battery pack at the current temperature; determining whether the real-time discharge time of the battery pack at the current temperature is greater than or equal to 0.8 times the theoretical reserve time, and whether the actual discharge capacity is greater than or equal to 0.8 times the theoretical discharge capacity; if so, the discharge test is stopped.

[0037] Specifically, this invention can calculate the theoretical minimum discharge time td of the battery at 100% capacity when converted to 25°C at the current temperature using the following formula. The capacity conversion formula is: CT = C × [1 + K × (θ - 25℃)]; In the formula, C is the theoretical discharge capacity; CT is the actual discharge capacity; K is the temperature coefficient, taken as 0.006 / ℃; θ is the current temperature. The capacity of LBA battery C10 is 2500Ah, which corresponds to a capacity of 1738Ah at a 4-hour discharge rate. The theoretical minimum discharge capacity is calculated as: CT=C×[1+0.006×(θ-25)], where C is taken as the theoretical value of 100% capacity, 1738Ah; θ is taken as the average electrolyte temperature of the five monitored batteries; the CT result is rounded to two decimal places. The theoretical minimum discharge time is calculated as: td = CT / 434.5.

[0038] When the battery discharge time reaches td and the actual discharge capacity is greater than or equal to the theoretical discharge capacity, or the battery pack terminal voltage is ≤108V, or the minimum voltage of a single cell is ≤1.8V, or the discharge time at the current temperature is ≥0.8 times the theoretical reserve time and the actual discharge capacity is ≥0.8 times the theoretical discharge capacity, then a stop discharge test is performed.

[0039] The discharge test method for nuclear power plant batteries of the present invention modifies the discharge test time (i.e., the target discharge time) to 3 hours or 5 hours, and at the same time modifies the discharge test current (i.e., the target discharge current). This reduces the discharge test current, the capacity requirements of the discharge circuit equipment, and the risk of fire, while also reducing the duration of the discharge test. This ensures that the battery discharge test does not prolong the critical path of unit overhaul and does not affect the unit's power generation.

[0040] refer to Figure 2 The present invention also provides a discharge test device for nuclear power plant batteries.

[0041] Specifically, such as Figure 2As shown, the discharge test apparatus for the nuclear power plant's batteries includes: The pre-test preparation unit 201 is used to perform pre-test preparation work before the discharge test of the battery pack.

[0042] The test parameter determination unit 202 is used to determine the discharge test parameters after the test preparation work is completed; the discharge test parameters include: target discharge time and target discharge current.

[0043] The discharge test execution unit 203 is used to perform a discharge test on the battery pack according to the target discharge time and target discharge current.

[0044] The discharge parameter monitoring unit 204 is used to monitor the test parameters of the battery pack in real time during the discharge test and obtain the real-time discharge parameters.

[0045] The battery quality assessment unit 205 is used to assess the quality of the battery pack based on real-time discharge parameters.

[0046] Specifically, the specific coordination and operation process between the various units in the discharge test device for nuclear power plant batteries can be referred to the discharge test method for nuclear power plant batteries mentioned above, and will not be repeated here.

[0047] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0048] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0049] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be implemented directly by hardware, a software module executed by a processor, or a combination of both. The software module can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0050] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They do not limit the scope of protection of the present invention. All equivalent changes and modifications made within the scope of the claims of the present invention should fall within the scope of the claims of the present invention.

Claims

1. A discharge test method for a nuclear power plant battery, characterized in that, Includes the following steps: Preparations for conducting a discharge test on the battery pack; After completing the test preparation work, determine the discharge test parameters; The discharge test parameters include: target discharge time and target discharge current; Perform a discharge test on the battery pack according to the target discharge time and target discharge current; During the discharge test, the test parameters of the battery pack are monitored in real time to obtain the real-time discharge parameters; The battery pack is evaluated for quality based on the real-time discharge parameters.

2. The discharge test method for nuclear power plant batteries according to claim 1, characterized in that, The determination of discharge test parameters includes: Obtain the factory data of the battery pack; The target discharge time, plate aging rate, initial fully charged battery pack terminal voltage, final fully charged battery pack terminal voltage, and discharge cutoff voltage are determined based on the factory data of the battery pack. Determine the corresponding discharge test current based on the target discharge time; The target discharge current is obtained by calculating based on the discharge test current, the plate aging rate, the terminal voltage of the fully charged battery pack at the beginning of its service life, the terminal voltage of the fully charged battery pack at the end of its service life, and the discharge cutoff voltage.

3. The discharge test method for nuclear power plant batteries according to claim 2, characterized in that, The calculation of the target discharge current based on the discharge test current, the plate aging rate, the terminal voltage of the fully charged battery pack at the beginning of its service life, the terminal voltage of the fully charged battery pack at the end of its service life, and the discharge cutoff voltage includes: The terminal voltage influence rate is calculated based on the terminal voltage of the fully charged battery pack at the beginning of its service life, the terminal voltage of the fully charged battery pack at the end of its service life, and the discharge cutoff voltage. The target discharge current is obtained by calculating based on the terminal voltage influence rate, the plate aging rate, and the discharge test current.

4. The discharge test method for nuclear power plant batteries according to claim 1, characterized in that, The target discharge current is calculated using the following formula: =A ;A=Lr(A)×[Lr(A)-Lr(U)]; Where Lr(A) is the plate aging rate; Lr(U) is the terminal voltage influence rate, Lr(U)=(U0-U1) / (U0-1.8), U0 is the terminal voltage of the fully charged battery pack at the beginning of its service life, U1 is the terminal voltage of the fully charged battery pack at the end of its service life, and 1.8 is the discharge cutoff voltage.

5. The discharge test method for nuclear power plant batteries according to claim 1, characterized in that, The real-time discharge parameters include: the real-time discharge voltage of a single battery cell; The quality assessment of the battery pack based on the real-time discharge parameters includes: The average voltage of a single battery cell is obtained by averaging the real-time discharge voltage of the single battery cell. The minimum voltage of a single battery cell is obtained by filtering based on its real-time discharge voltage. The quality of the battery pack is assessed based on the average voltage and the minimum voltage of each individual cell.

6. The discharge test method for a nuclear power plant battery according to claim 5, characterized in that, The quality assessment of the battery pack based on the average voltage and minimum voltage of each individual cell includes: Determine whether the average voltage and the minimum voltage of the single cell are both greater than a set value. If so, continue discharging until the target discharge time is reached, and determine that the battery pack is in good condition. If the average voltage of a single battery cell or the minimum voltage of a single battery cell is less than the set value, and the real-time discharge time is less than the target discharge time, then the discharge test is stopped, and the battery pack is deemed unqualified.

7. The discharge test method for a nuclear power plant battery according to any one of claims 1-6, characterized in that, The method further includes: Obtain the real-time discharge time and actual discharge capacity of the battery pack; Determine whether the real-time discharge time of the battery pack has reached the minimum required discharge time, and whether the real-time discharge capacity is greater than or equal to the theoretical discharge capacity. If so, then stop the discharge test.

8. The discharge test method for a nuclear power plant battery according to any one of claims 1-6, characterized in that, The method further includes: Obtain the real-time discharge time and actual discharge capacity of the battery pack at the current temperature; Determine whether the real-time discharge time of the battery pack at the current temperature is greater than or equal to 0.8 times the theoretical reserve time, and whether the actual discharge capacity is greater than or equal to 0.8 times the theoretical discharge capacity; If so, then stop the discharge test.

9. The discharge test method for a nuclear power plant battery according to any one of claims 1-6, characterized in that, The test preparation work before performing the discharge test of the battery pack includes: Perform a discharge test environment inspection; Perform a visual inspection of the battery pack; Measure basic data before the battery pack discharge test.

10. A discharge test device for a nuclear power plant battery, characterized in that, include: The pre-test preparation unit is used to perform pre-test preparation work before the discharge test of the battery pack. The test parameter determination unit is used to determine the discharge test parameters after the test preparation work is completed; The discharge test parameters include: target discharge time and target discharge current; A discharge test execution unit is used to perform a discharge test on the battery pack according to the target discharge time and target discharge current. The discharge parameter monitoring unit is used to monitor the test parameters of the battery pack in real time during the discharge test and obtain the real-time discharge parameters. A battery quality assessment unit is used to assess the quality of the battery pack based on the real-time discharge parameters.

Images