Generator grounding resistance testing device and system and protection method

Abstract

The invention discloses a generator grounding resistance testing device, system and protection method, and the testing device is provided with a resistor array unit which is provided with a plurality of testing resistors which are sequentially connected in series, and a switching unit which is provided with a plurality of testing switches which are connected with the testing resistors in parallel in a one-to-one correspondence manner. And two ends of the resistor array unit are respectively connected with a neutral point and grounded. The automation of the generator stator grounding protection verification process which is originally manually participated is realized, and the overall verification efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of generator protection in nuclear power plants, and particularly relates to a generator grounding resistance testing device, system and protection method. Background Art

[0002] Under the existing technology, the neutral point of the generator in a large nuclear power plant is mostly grounded by a grounding transformer, and a 100% stator grounding protection is designed. This protection is based on the injection measurement principle and must be simulated and verified during the no-load test of the generator after starting. After different known test resistors are connected in series in the circuit, a 20Hz AC signal is applied to the circuit, and the grounding resistance value is automatically calculated from the device. Then, it is compared with the test resistor value added to the circuit. If there is a deviation, the device corrects the measurement result to ensure the correctness of the grounding resistance measurement result during the subsequent actual operation of the generator. Since the test resistor needs to be connected in series to the primary circuit, there is a certain risk of electric shock. To ensure personal safety, the replacement of the test resistor each time needs to be carried out under the premise of ensuring personal safety. Each time the resistor value is changed, the generator needs to be shut down, and the generator shutdown also requires demagnetization. After taking safety measures, the number of resistors needs to be manually reassembled as required, and the wiring needs to be checked to be correct before it can be used. The operation steps are cumbersome and the efficiency is low. Therefore, there is an urgent need for a new generator test system to solve the problem of low efficiency in the calibration process of the stator grounding protection of the generator in the current nuclear power plant. Summary of the Invention

[0003] Embodiments of the present invention provide a generator grounding resistance testing device, system and protection method, aiming to solve the problem of low efficiency in the calibration process of the stator grounding protection of the generator in the existing technology in nuclear power plants.

[0004] In a first aspect, the present invention provides a generator grounding resistance testing device, including: a resistor array unit, including a plurality of test resistors connected in series in sequence, a first end of the resistor array unit is connected to the neutral point of the generator stator coil, and a second end of the resistor array unit is grounded; a switching unit, including a plurality of test switches, each of the test switches is respectively connected in parallel with each of the test resistors; wherein, any one of the test switches is used to short-circuit the corresponding test resistor when closed to change the resistance value of the resistor array unit.

[0005] In a second aspect, the present invention provides a generator test system, including the generator grounding resistance testing device as described above. The system further includes: a local control module, including a main control unit, a switch control unit and a communication unit, the main control unit is connected to the switch control unit and the communication unit, and the switch control unit is used to control each test switch; a mobile terminal, communicatively connected to the communication unit module, and is used to remotely obtain the data information of the main control unit or remotely issue a control instruction.

[0006] In a third aspect, the present invention provides a generator protection method based on the generator test system as described above. The method is characterized by including the following steps: connecting a resistor array to the neutral point grounding circuit of the generator; issuing a target resistance value command through a mobile terminal, remotely controlling the opening and closing states of the switch unit to adjust the total resistance value connected to the neutral point grounding circuit of the generator; continuously controlling the opening and closing states of the switch unit, switching different resistance values until the stator grounding protection verification of the generator is completed.

[0007] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0008] In the technical solution of the present invention, by providing a resistor array unit with a plurality of test resistors connected in series in sequence and a switching unit with a plurality of test switches connected in parallel corresponding to the test resistors one by one, and connecting both ends of the resistor array unit to the neutral point and the ground respectively. The originally manually participated stator grounding protection verification process of the generator is automated, improving the overall verification efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the following described drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on the structures shown in these drawings.

[0010] Figure 1 It is a schematic structural diagram of the generator protection device according to the embodiment of the present invention;

[0011] Figure 2 It is a schematic diagram of the connection logic relationship of each functional device of the generator test system according to the embodiment of the present invention;

[0012] Figure 3 It is a method step diagram of the generator protection method according to the embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0013] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0014] It should be understood that when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or their groups.

[0015] It should also be understood that the terminology used in this specification of the present invention is for the purpose of describing particular embodiments only and is not intended to limit the present invention. As used in this specification of the present invention and the appended claims, unless the context clearly dictates otherwise, the singular forms "a", "an", and "the" are intended to include the plural forms.

[0016] It should be further understood that the term "and / or" as used in this specification of the present invention and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0017] To solve the problem of low efficiency in the calibration process of generator stator grounding protection in the prior art, the present invention provides a generator grounding resistance testing device. The testing device includes: a resistor array unit, which includes a plurality of sequentially connected testing resistors. The first end of the resistor array unit is connected to the neutral point of the generator stator coil, and the second end of the resistor array unit is grounded; a switching unit, which includes a plurality of testing switches, and each of the testing switches is respectively connected in parallel with each of the testing resistors one by one; wherein, any of the testing switches is used to short-circuit the corresponding testing resistor when closed to change the resistance value of the resistor array unit. The resistor array unit is composed of a plurality of resistor units, and these resistor units are connected in series. The resistance value of each resistor unit can be a fixed value or a suitable standard resistor can be selected according to requirements. In this embodiment, the first end of the resistor array unit is connected to the neutral point of the generator stator coil, and the second end is grounded. Through this configuration, the resistor array unit can be combined with different numbers of resistors to meet different testing requirements. The series arrangement between each testing resistor ensures that the resistor array unit has the ability to continuously change the resistance during the testing process, so as to achieve multi-level grounding resistance testing and adapt to the protection calibration requirements of different generators. In practical applications, the resistor array unit provides high precision and stability, making the test results more accurate. The main function of the switching unit is to switch the testing resistors in the resistor array unit through a plurality of testing switches. Each testing switch corresponds to each testing resistor in the resistor array unit one by one and is connected in parallel. The working principle of the testing switch is to short-circuit the corresponding testing resistor by closing a certain testing switch, thereby effectively changing the total resistance value of the resistor array unit. Specifically, the operation of the testing switch can quickly and accurately control the access and switching of the testing resistor, so as to finely adjust the total resistance of the resistor array unit. In this way, the testing device can adjust different resistance values for testing according to requirements, meeting the requirements of different generator stator grounding protection calibrations. Each testing switch of the switching unit can be controlled independently to achieve flexible resistance switching. The staff only needs to select the corresponding testing resistor through the system operation interface to automatically complete the switch switching operation, greatly simplifying the complex process of traditional manual resistance adjustment. In addition, through precise resistance switching, the testing device can complete the measurement of the grounding resistance value faster, improving the work efficiency.

[0018] In the embodiment of the present invention, the resistor array unit cooperates with the switching unit to form an automatic control system. During the specific use process, the staff can select the required testing resistor through the operation interface of the control system connected to the generator grounding resistance testing device, without the need for manual access or replacement of the resistor. The whole process does not involve direct human operation of the grounding circuit, greatly reducing the risk of electric shock and the possibility of human operation errors.

[0019] In one embodiment, the resistor array unit includes N serially connected test resistors, and the switch unit includes N - 1 test switches, wherein N - 1 serially connected test resistors are respectively connected in parallel with the test switches. In this embodiment, the resistor array unit is composed of N serially connected test resistors, the switch unit includes N - 1 test switches, and each test switch is respectively connected in parallel with a test resistor. This enables each test switch to independently control its corresponding test resistor. When the test switch is closed, the test switch will be connected in parallel with the corresponding test resistor, thereby effectively changing the total resistance value of the resistor array unit. Specifically, when a certain test switch is closed, the switch will short-circuit and bypass the corresponding test resistor, reducing the overall resistance value. In this way, the test device can quickly switch between multiple different resistance settings, making the test process more flexible and efficient. For example, assuming that the entire resistor array includes 10 serially connected test resistors, then the switch unit will include 9 test switches. By closing different switches, some resistors can be selectively bypassed, thereby adjusting the total resistance value of the test device. In this way, the tester can flexibly configure the required resistance value according to the grounding resistance requirements of the generator, further improving the accuracy and efficiency of the test.

[0020] In one embodiment, the switching unit further includes a terminal block, the test switch is a contactor, a first end of the contactor is connected to an end of the corresponding parallel-connected test resistor close to the neutral point, a second end of the contactor is connected to an end of the corresponding test resistor away from the neutral point, and a third end of the contactor is connected to the terminal block. In this embodiment, the contactor replaces the traditional mechanical switch and switches the resistor in a more efficient and reliable manner. The terminal block provides a unified access point for the contactor, making the electrical connection of the entire system more compact and stable, and facilitating maintenance and troubleshooting. Through the terminal block, the connection of the contactor is more concise, and at the same time, the reliability and operability of the system are improved. The main function of the terminal block in this system is to provide a wiring interface for each contactor, so as to achieve more efficient and flexible resistor control. Each contactor is connected to other components of the system through the terminal block, ensuring that the contactor can accurately switch the resistor during actual operation. The first end of the contactor is connected to an end of the corresponding test resistor close to the neutral point. This end is responsible for making an electrical connection with a series-connected test resistor opposite to the connection position in the resistor array unit. When the contactor is closed, the current first passes through this end and through the test resistor. The second end of the contactor is connected to an end of the corresponding test resistor away from the neutral point. This port is connected to the other end of the test resistor opposite to the connection position through the closing of the contactor, ensuring that the current can pass through the resistor and enter the next part of the circuit. The third end of the contactor is connected to the terminal block. Through the terminal block, the contactor is electrically connected to other parts of the entire test device, so as to achieve the selection of different resistor configurations. Through the connection of the terminal block, different test resistors or test modes can be quickly switched according to needs.

[0021] In one embodiment, each of the test resistors is 1 kΩ. The selection of 1 kΩ as the standard resistance value is mainly based on the following reasons: The 1 kΩ resistance value has relatively stable electrical performance and can maintain a relatively consistent resistance value under different environmental conditions, thus ensuring the data reliability during the test. For most generator grounding resistance tests, the 1 kΩ resistance value is a relatively appropriate starting point and can cover the test ranges of most conventional generator grounding resistances. By selectively switching different test resistors, the system can meet the requirements of different test scenarios. A lower resistance value can be used for testing under conditions of larger current without causing excessive current fluctuations, ensuring safety during the test operation. The 1 kΩ resistance value provides a moderate current load for the generator grounding resistance test, ensuring both the test accuracy and operation safety. Specifically in use, 10 test resistors can meet the resistance change range required for the 100% stator grounding test of the generator, that is, from 1 kΩ to 10 kΩ.

[0022] The present invention also discloses a generator test system, which includes the generator grounding resistance test device described in each of the above embodiments. In addition, the generator test system further includes: a local control module, including a main control unit, a switch control unit and a communication unit, the main control unit is connected to the switch control unit and the communication unit, and the switch control unit is used to control each test switch; a mobile terminal, which is communicatively connected to the communication unit module and is used to remotely obtain the data information of the main control unit or remotely issue control instructions. The local control module is composed of a main control unit, a switch control unit and a communication unit. Among them, in actual use, the main control unit selects a CPU with the model of STM32H743VT6. The main control unit is connected to the switch control unit and the communication unit and is responsible for the coordination and management of the entire system. The main control unit is responsible for the central control of the system, receives control instructions from operators or remote terminals, and adjusts the system state according to these instructions. The main control unit directly controls the switching operation of the test switch through cooperation with the switch control unit to ensure that the test of the generator grounding resistance can be accurately executed according to the preset program. The switch control unit is directly connected to contactors, test switches, etc. in the test device and is responsible for controlling the switching actions of these components. It can accurately switch the test resistance according to the instructions of the main control unit and realize the combination of different test resistances, thereby ensuring the accuracy of the grounding resistance test. The communication unit is connected to the main control unit and undertakes the functions of data transmission and communication. It transmits information such as the working state and test data of the local system to the remote terminal and also accepts the instructions issued by the remote terminal, so as to realize remote control and data monitoring. Specifically, in actual use, the communication unit uses an Internet of Things communication module with the model of SIM7600CE. Operators can obtain the operation data and test results of the system in real time through the mobile terminal and can remotely issue instructions to control the system to perform specific operations.

[0023] When grounding resistance testing is required, after the main control unit receives a remote or local input instruction, it will send a control signal to the switch control unit, instructing the switch control unit to turn on or off the corresponding test switch. The switch control unit operates the contactor according to the signal to connect or disconnect different test resistances. The main control unit is also responsible for real-time monitoring of the data generated during the grounding resistance test process and sending this data to the communication unit. The main control unit will also generate a test report based on the measured grounding resistance value and send the data to the remote terminal in real time. Through the communication unit, the main control unit can perform two-way data transmission with the remote terminal. On the remote terminal, no matter where the test site is located, operators can view the real-time test data, equipment status, and perform remote operations, fault diagnosis, parameter adjustment and other operations.

[0024] In one embodiment, the local control module further includes a resistance value acquisition unit, which is connected to the resistance unit and the main control unit, and is used to obtain the resistance value of the resistance unit. The resistance value acquisition unit is responsible for obtaining the resistance value of the resistance unit and transmitting it to the main control unit. The resistance value acquisition unit feeds back the real-time measured resistance value to the main control unit. The main control unit can judge whether the current grounding resistance meets the requirements according to these real-time data. If the resistance value is not within the set range, the main control unit will adjust the resistance unit configuration through the switch control unit and switch to other resistance values for testing. After receiving the resistance value, the main control unit will store it in the system database and perform data analysis according to a preset algorithm. If necessary, the system will also generate a test report, recording the resistance change trend, test time and other relevant data. Through the real-time monitoring and analysis of these data, the system can better judge whether the generator grounding resistance is in a normal working state. When an abnormality occurs or the resistance value needs to be adjusted during the test, the main control unit can send relevant information to the remote terminal through the communication unit to notify the operator to take corresponding treatment measures. Through the solution of this embodiment, it is ensured that the generator test system can measure the resistance value in real time and accurately, thereby optimizing the entire test process. The collaborative work between the resistance value acquisition unit, the resistance unit and the main control unit makes the entire test system more intelligent and accurate. Specifically, the model number of the resistance value acquisition unit in this embodiment is 875-RES-D.

[0025] In one embodiment, the generator test system further includes a remote platform, which is communicatively connected to at least one of the mobile terminals and at least one of the communication units. The remote platform is used to realize two-way data transmission between any one of the mobile terminals and any one of the main control units. The remote platform module conducts data transmission and interaction with devices such as the main control unit and the mobile terminal through the communication unit, enhancing the remote operation ability of the system. Specifically, the two-way data transmission function between the remote platform and the mobile terminal and the main control unit enables testers to monitor and adjust the working state of the system in real time regardless of their location. The remote platform is connected to the main control unit in the system through the communication unit. The communication unit usually consists of wireless modules such as Wi-Fi, Bluetooth, 4G / 5G or wired communication interfaces, ensuring that data transmission is not restricted by geographical location. In this embodiment, the connection method of the communication unit can be flexibly selected according to the actual requirements of the on-site environment. Whether it is a local area network (LAN) or a wide area network (WAN), it can support the communication between the remote platform and the main control unit. When the main control unit collects resistance data or test results, these data will be uploaded to the remote platform through the communication unit. The remote platform can not only receive data from the main control unit, but also send instructions or modification commands to the main control unit. For example, when the test result exceeds a predetermined threshold, the remote platform can change the working mode of the test system or modify the settings of the resistance unit by sending adjustment commands. The remote platform is connected to at least one mobile terminal, which usually refers to intelligent devices used by operators, such as mobile phones, tablets or laptops. In addition, the remote platform is not only a data transmission medium, but also undertakes important data processing and display functions. The platform can receive various test data uploaded by the main control unit, and conduct real-time analysis and display to help users quickly understand the test status of the generator grounding resistance.

[0026] In one embodiment, the generator test system further includes a display and control unit, which is connected to the main control unit. The display and control unit is used to locally obtain the data information of the main control unit or remotely issue control commands. The display and control unit is responsible for real-time displaying the data of the main control unit and can receive control commands input by local users through the user interaction interface. The display and control unit is connected to the main control unit through a data transmission interface. The main control unit is responsible for executing actual test tasks, collecting system data and processing it, while the display and control unit serves as an interface for data interaction and local operations. The connection method between the display and control unit and the main control unit generally includes serial communication such as RS-232 and RS-485 or network communication such as Ethernet or Wi-Fi, and the specific selection is optimized according to on-site requirements and environmental factors. The main control unit transmits the collected data information to the display and control unit in real time, such as the operating state of the generator, resistance value, test results, etc. The display and control unit then displays this data through a graphical interface or a text interface for the operator to view and analyze. The data display can include key parameters such as voltage, current, and ground resistance to help the operator timely understand the operating state of the system.

[0027] In one embodiment, after receiving a control instruction, the main control unit obtains the actual resistance value through the resistance value acquisition unit and verifies the deviation between the actual resistance value and the target resistance value set by the control instruction. If the deviation exceeds a preset threshold, an alarm is triggered and the switch operation is aborted. The main control unit generates a control instruction according to the test requirements and sets the target resistance value. These target resistance values are usually based on experimental standards or set operation ranges, aiming to ensure the normal operation of the generator. The setting of the target resistance value usually needs to combine the equipment specifications and on-site test conditions. In practical applications, due to the complex operating environment of electrical equipment, there may be situations where the actual resistance value deviates greatly due to external interference, equipment aging, or improper operation, etc., and cannot meet the expected target value. When the deviation of the actual resistance value exceeds the preset threshold set by the system, the main control unit will first trigger an alarm. Once the deviation between the actual resistance value and the target resistance value exceeds the preset threshold, the main control unit will automatically trigger an alarm through the built-in alarm module of the system. The alarm method can be an audible alarm, a visual alarm, such as displaying an error message on the screen, or transmitting an alarm signal to the remote monitoring interface of the operator through the network. To avoid equipment damage or system anomalies caused by excessive resistance deviation, the main control unit will immediately abort the ongoing switch operation when the deviation exceeds the threshold. By aborting the switch operation, the system can prevent bad operations from further affecting the stability of the generator and ensure the safety of the equipment and personnel. In addition to triggering audible or visual warnings, the alarm system will also display detailed error information on the display control unit or remote monitoring system, such as the actual resistance value, target resistance value, deviation value, and specific over-limit amplitude. These information help the operator quickly identify the problem and handle it in a timely manner. In addition, there is an adjustable deviation threshold in the system, and the user can dynamically adjust the size of this threshold according to actual needs or specific test requirements. Through refined threshold setting, the system can flexibly control the deviation range according to different test scenarios to avoid false alarms or missed alarms. When the system detects that the deviation exceeds the threshold multiple times, the main control unit will start the advanced protection mode and further take measures such as power-off protection and test mode switching to reduce potential risks caused by operation errors or equipment failures.

[0028] The present invention also discloses a generator protection method, based on the generator test system described in the above embodiments, the generator protection method includes the following steps:

[0029] S110. Connect the resistor array to the neutral grounding circuit of the generator;

[0030] S120. Send a target resistance value instruction through the mobile terminal, and remotely control the opening and closing state of the switch unit to adjust the total resistance value connected to the neutral grounding circuit of the generator;

[0031] S130. Continuously control the opening and closing state of the switching unit to switch different resistance values until the verification of the generator stator grounding protection is completed.

[0032] When implementing the generator protection method, first connect the resistance array to the neutral grounding circuit of the generator. The function of the resistance array is to provide a series of adjustable resistance values to simulate different grounding states of the generator. Through the resistance array, different grounding resistance conditions can be simulated during the test, so as to comprehensively verify and calibrate the protection system of the generator. After completing the connection of the resistance array, the operator will issue a target resistance value command through the mobile terminal. The mobile terminal is connected to the main control unit through a wireless communication network to transmit the target resistance value setting in real time. After receiving the target resistance value command, the main control unit will adjust the total resistance value connected to the neutral grounding circuit of the generator by controlling the opening and closing state of the switching unit. In order to complete the verification of the generator stator grounding protection, the system will continuously control the opening and closing state of the switching unit to switch different resistance configurations. Through this control method, the system can verify the response of the generator protection device under a series of resistance conditions. Through the above steps, the system can continuously and accurately adjust the total resistance value of the grounding circuit and perform the verification of the generator stator grounding protection under different resistance conditions. The ultimate purpose of the verification is to verify the working state of the generator protection device under different grounding resistance conditions, ensure that the device can automatically execute the protection operation in case of abnormal grounding, and ensure the normal operation of the generator.

[0033] A schematic block diagram of a computer device provided by an embodiment of the present application. The computer device 500 can be a terminal or a server. Among them, the terminal can be an electronic device with communication functions such as a desktop computer, a tablet computer, and a smart phone. The server can be an independent server or a server cluster composed of multiple servers.

[0034] The computer device 500 includes a processor 502, a memory, and a network interface 505 connected through a system bus 501. Among them, the memory can include a non-volatile storage medium 503 and an internal memory 504.

[0035] The non-volatile storage medium 503 can store an operating system 5031 and a computer program 5032. The computer program 5032 includes program instructions, and when the program instructions are executed, the processor 502 can be made to execute a generator protection method.

[0036] The processor 502 is used to provide computing and control capabilities to support the operation of the entire computer device 500.

[0037] The internal memory 504 provides an environment for the operation of the computer program 5032 in the non-volatile storage medium 503. When the computer program 5032 is executed by the processor 502, the processor 502 can be caused to execute a generator protection method.

[0038] The network interface 505 is used for network communication with other devices. Those skilled in the art can understand that the shown structure is only a block diagram of some structures related to the solution of this application, and does not constitute a limitation on the computer device 500 to which the solution of this application is applied. Specifically, the computer device 500 may include more or fewer components than those shown in the figure, or combine some components, or have different component arrangements.

[0039] Among them, the processor 502 is used to run the computer program 5032 stored in the memory to implement the steps of the above method.

[0040] It should be understood that in the embodiments of this application, the processor 502 may be a central processing unit (CPU), and the processor 502 may also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), off-the-shelf programmable gate arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. Among them, the general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0041] Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing related hardware through a computer program. The computer program includes program instructions, and the computer program can be stored in a storage medium, and the storage medium is a computer-readable storage medium. The program instructions are executed by at least one processor in the computer system to implement the process steps of the embodiments of the above method.

[0042] Therefore, the present invention also provides a storage medium. The storage medium may be a computer-readable storage medium. The storage medium stores a computer program, and the computer program includes program instructions. When the program instructions are executed by the processor, the processor is caused to execute the steps of the above method.

[0043] The storage medium may be a USB flash drive, a mobile hard disk, a read-only memory (ROM), a magnetic disk, an optical disk, or other computer-readable storage media that can store program codes.

[0044] Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be implemented by electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described according to functions in the above description. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present invention.

[0045] In several embodiments provided by the present invention, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of each unit is only a logical function division, and there may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed.

[0046] The steps in the method embodiments of the present invention can be adjusted, combined, and deleted according to actual needs. The units in the device embodiments of the present invention can be combined, divided, and deleted according to actual needs. In addition, the functional units in each embodiment of the present invention can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit.

[0047] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a storage medium. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a terminal, or a network device, etc.) to execute all or part of the steps of the methods described in each embodiment of the present invention.

[0048] As described above, the above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of various equivalent modifications or substitutions, and these modifications or substitutions should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A generator grounding resistance testing device, characterized in that, Including: A resistor array unit, including a plurality of test resistors connected in series in sequence. The first end of the resistor array unit is connected to the neutral point of the generator stator coil, and the second end of the resistor array unit is grounded. A switching unit, including a plurality of test switches, and each of the test switches is respectively connected in parallel with each of the test resistors one by one. Wherein, when any of the test switches is used to be closed, it shorts the corresponding test resistor to change the resistance value of the resistor array unit.

2. The generator grounding resistance test device according to claim 1, wherein The resistor array unit includes N series-connected test resistors, and the switch unit includes N - 1 test switches. Among them, N - 1 series-connected test resistors are respectively connected in parallel with the test switches.

3. The generator grounding resistance test device according to claim 1, characterized in that The switching unit further includes a terminal block. The test switch is a contactor. The first end of the contactor is connected to the end of the corresponding parallel-connected test resistor close to the neutral point, the second end of the contactor is connected to the end of the corresponding test resistor far from the neutral point, and the third end of the contactor is connected to the terminal block.

4. The generator grounding resistance testing device according to any one of claims 1 to 3, characterized in that, Each of the test resistors is 1 kΩ.

5. A generator test system, including the generator grounding resistance test device according to any one of claims 1 to 4. The system further includes: A local control module, including a main control unit, a switch control unit and a communication unit. The main control unit is connected to the switch control unit and the communication unit, and the switch control unit is used to control each test switch. A mobile terminal, communicatively connected to the communication unit module, and is used to remotely obtain the data information of the main control unit or remotely issue a control instruction.

6. The generator test system according to claim 5, wherein, The local control module further includes a resistance value acquisition unit. The resistance value acquisition unit is connected to the resistance unit and the main control unit, and the resistance value acquisition unit is used to obtain the resistance value of the resistance unit.

7. The generator test system according to claim 6, wherein It further includes a remote platform. The remote platform is communicatively connected to at least one mobile terminal and at least one communication unit, and the remote platform is used to realize two-way data transmission between any one of the mobile terminals and any one of the main control units.

8. The generator test system according to claim 6, wherein It further includes a display and control unit. The display and control unit is connected to the main control unit, and the display and control unit is used to locally obtain the data information of the main control unit or remotely issue a control instruction.

9. The generator test system according to any one of claims 6 to 8, characterized in that, After receiving the control instruction, the main control unit obtains the actual resistance value through the resistance value acquisition unit and verifies the deviation between the actual resistance value and the target resistance value set by the control instruction. If the deviation exceeds the preset threshold, an alarm is triggered and the switch action is aborted.

10. A generator protection method, based on the generator test system according to any one of claims 5 to 9, characterized in that Including the following steps: Connect the resistor array to the generator neutral point grounding circuit. Issue a target resistance value instruction through the mobile terminal, and remotely control the opening and closing state of the switch unit to adjust the total resistance value connected to the generator neutral point grounding circuit. Continuously control the opening and closing state of the switch unit, switch different resistance values until the generator stator grounding protection check is completed.

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