A lightning arrester calibration system

Abstract

The present invention discloses a lightning arrester calibration system, belonging to the technical field of lightning arrester calibration, which includes a power supply, a current output unit, a current generation control unit, an anti-interference unit and a protection unit; the power supply is used to generate the current required for lightning arrester calibration and output it to the current output unit, and the circuits for generating different currents in the power supply are not connected, and the current includes impulse current, leakage current and measurement and control current; the current output unit is used to control the output of the current, and the current generation control unit is used to control the process of the power supply generating the current; the anti-interference unit is used to disconnect the path of the power supply outputting the leakage current during the impulse current test, and isolate the input of the circuit for generating the impulse current in the power supply during the leakage current test; the protection unit is used to shunt the impulse current during the impulse current test, and absorb and store the residual high voltage in the circuit when switching to the leakage current test. The present invention avoids interference through power supply isolation and realizes circuit protection through the anti-interference unit and the protection unit.

Description

Technical Field

[0001] The present invention relates to a lightning arrester calibration system, belonging to the technical field of lightning arrester calibration. Background Art

[0002] Lightning arrester calibration is an important process for lightning arrester quality inspection and is widely used in the functional test of lightning arresters and the regular on-site calibration of power grids by power supply departments. Due to different calibration schemes used, the quality of lightning arrester calibration equipment varies. In the lightning arrester calibration test, the arc drawing and discharge shock waves generated by high-voltage discharge can cause physical and psychological harm to operators, and can also cause high-voltage interference to the external power supply grid, resulting in abnormal operation of other equipment in the grid. The lightning arrester calibration equipment itself is most affected by the impact and there is a risk of failure and damage. Summary of the Invention

[0003] The purpose of the present invention is to provide a lightning arrester calibration system to avoid the adverse effects on the power grid existing in the prior art during lightning arrester calibration.

[0004] To achieve the above purpose, the present invention is implemented by the following technical solutions:

[0005] The present invention provides a lightning arrester calibration system, including: a power supply, a current output unit, a current generation control unit, an anti-interference unit, and a protection unit;

[0006] The power supply is used to generate the current required for lightning arrester calibration and output the generated current to the current output unit. The circuits for generating different currents in the power supply are not connected. The currents include impulse current, leakage current, and measurement and control current;

[0007] The current output unit is used to control the output of the current, and the current generation control unit is used to control the process of generating current by the power supply;

[0008] The anti-interference unit is connected to the power supply and is used to disconnect the path for the power supply to output leakage current during the impulse current test, and isolate the input of the circuit for generating impulse current in the power supply during the leakage current test;

[0009] The protection unit is used to shunt the impulse current during the impulse current test, and is also used to absorb and store the residual high voltage in the circuit when switching from the impulse current test to the leakage current test.

[0010] Further, the power supply includes an impulse current generation circuit, a first measurement and control current generation circuit, an AC leakage current generation circuit, a second measurement and control current generation circuit, a DC leakage current generation circuit, and a third measurement and control current generation circuit;

[0011] The lightning arrester calibration includes an impulse current test, an AC leakage current test, and a DC leakage current test;

[0012] The impulse current generating circuit is used to generate the impulse current required in the arrester calibration;

[0013] The first measurement and control current generating circuit is used to generate the first measurement and control current required in the arrester calibration. The first measurement and control current is the measurement and control current used during the impulse current test by using the impulse current;

[0014] The AC leakage current generating circuit is used to generate the AC leakage current required in the arrester calibration;

[0015] The second measurement and control current generating circuit is used to generate the second measurement and control current required in the arrester calibration. The second measurement and control current is the measurement and control current used during the AC leakage current test by using the AC leakage current;

[0016] The DC leakage current generating circuit is used to generate the DC leakage current required in the arrester calibration;

[0017] The third measurement and control current generating circuit is used to generate the third measurement and control current required in the arrester calibration. The third measurement and control current is the measurement and control current used during the DC leakage current test by using the DC leakage current.

[0018] Further, the impulse current generating circuit includes a power supply unit, an AC high-voltage pulse transformer, a bridge rectifier, and a high-voltage pulse capacitor connected in sequence. The AC high-voltage pulse transformer is used to convert the current provided by the power supply unit into AC high voltage and transmit it to the bridge rectifier. The bridge rectifier is used to convert the AC high voltage into DC high voltage and transmit it to the high-voltage pulse capacitor. The high-voltage pulse capacitor is used to store the energy of the DC high voltage and then generate the energy of the impulse current and output the impulse current;

[0019] The first measurement and control current generating circuit, the AC leakage current generating circuit, the second measurement and control current generating circuit, the DC leakage current generating circuit, and the third measurement and control current generating circuit are respectively different transformers connected to the power supply unit.

[0020] Further, the current output unit includes two high-voltage reed relays and a self-locking switch. Each high-voltage reed relay includes a normally open contact, a normally closed contact, a common terminal, and a coil;

[0021] When controlling the output of the current, in the current output unit, two normally open contacts are respectively connected to the positive and negative poles of the impulse current output terminal in the power supply, one normally closed contact is connected to the live wire of the AC leakage current output terminal and the positive pole of the DC leakage current output terminal in the power supply, and the other normally closed contact is connected to the neutral wire of the AC leakage current output terminal and the negative pole of the DC leakage current output terminal in the power supply. The common terminal is used to output the current flowing through the high-voltage reed relay, and the two coils are connected in parallel and controlled by a self-locking switch;

[0022] When the self-locking switch is turned on, the high-voltage reed relay coil is energized and attracted. At this time, the normally open contact is conducted with the common terminal, and the impulse current provided by the power supply is output through the common terminal; when the self-locking switch is turned off, the high-voltage reed relay coil loses power and releases. At this time, the normally closed contact is conducted with the common terminal, and the AC leakage current or DC leakage current provided by the power supply is output through the common terminal.

[0023] Further, the current generation control unit is an impulse current generation control unit, including a resistor R1, a high-voltage vacuum relay, and a manual key switch. The high-voltage vacuum relay is used to control the process of the high-voltage pulse capacitor generating an impulse current using the DC high voltage stored in itself. The high-voltage vacuum relay includes a normally open contact, a common terminal, and a coil;

[0024] In the impulse current generation control unit, after the normally open contact is connected in series with the resistor R1, it is connected to the positive pole of the high-voltage pulse capacitor, the common terminal is connected to the negative pole of the high-voltage pulse capacitor, one end of the coil is grounded, and the other end is connected to a DC power supply through the manual key switch;

[0025] When the manual key switch is turned on, the high-voltage vacuum relay coil is energized and attracted, and its normally open contact is instantaneously short-circuited with the common terminal.

[0026] Further, the anti-interference unit includes an electromagnetic relay, a self-locking switch, and a manual key switch. The electromagnetic relay includes a normally open contact, a normally closed contact, a common terminal, and a coil;

[0027] In the anti-interference unit, the common terminal is connected to the live wire of the power supply outside the lightning arrester calibration system, the normally open contact is connected to the live wire of the primary side of the AC high-voltage pulse transformer, the normally closed contact is connected to the live wire of the secondary side of the transformer in the AC leakage current generation circuit or the DC leakage current generation circuit, one end of the coil is connected to the self-locking switch, and the other end of the coil is grounded;

[0028] The electromagnetic relay is controlled to be attracted and released by a self-locking switch. During the impulse current test, when the self-locking switch is pressed, the electromagnetic relay is in the attracted state, the normally open contact and the common terminal are in the conducting state. At this time, the high-voltage pulse capacitor outputs an impulse current, and the normally closed contact and the common terminal are in the disconnected state. At this time, the power supply does not output leakage current. During the leakage current test, when the self-locking switch is bounced up, the electromagnetic relay is in the released state, the normally closed contact and the common terminal are conducting. At this time, the AC leakage current generating circuit outputs an AC leakage current or the DC leakage current generating circuit outputs a DC leakage current, and the impulse current generating circuit does not output an impulse current.

[0029] Further, it further includes a leakage measurement and control unit, and the leakage measurement and control unit is used to control and measure the AC leakage current and DC leakage current generated by the power supply;

[0030] The leakage measurement and control unit includes an ammeter, an adjustable potentiometer, a self-locking switch, two AC measurement current-limiting resistors, two DC measurement current-limiting resistors, a first micro electromagnetic relay, a second micro electromagnetic relay, and a third micro electromagnetic relay. The components of the first micro electromagnetic relay, the second micro electromagnetic relay, and the third micro electromagnetic relay are the same, and each includes a coil, two normally open contacts, two normally closed contacts, and two common terminals. The three coils are connected in parallel and are all connected to the self-locking switch. The self-locking switch controls the attraction and release of the first micro electromagnetic relay, the second micro electromagnetic relay, and the third micro electromagnetic relay through the three coils respectively;

[0031] On the first micro electromagnetic relay, the adjustable potentiometer is connected to the secondary side of the transformer in the AC leakage current generating circuit. The two common terminals are respectively connected to the adjustable end and the zero line end of the adjustable potentiometer. The two normally open contacts are respectively connected to the two input ends of the bridge rectifier. One normally closed contact is connected to the live wire of the AC leakage current output end of the power supply and the positive pole of the DC leakage current output end, and the other normally closed contact is connected to the zero line of the AC leakage current output end of the power supply and the negative pole of the DC leakage current output end;

[0032] On the second micro electromagnetic relay, the two normally open contacts are respectively connected to the two output ends of the bridge rectifier, the two normally closed contacts are suspended, one common terminal is connected to the live wire of the AC leakage current output end of the power supply and the positive pole of the DC leakage current output end, and the other common terminal is connected to the zero line of the AC leakage current output end of the power supply and the negative pole of the DC leakage current output end;

[0033] On the third micro electromagnetic relay, the two normally closed contacts are respectively connected to the two AC measurement current-limiting resistors for measuring the AC leakage current. The two normally open contacts are respectively connected to the two DC measurement current-limiting resistors, and the two common terminals are connected to the two input ends of the ammeter;

[0034] When the first micro electromagnetic relay is released and the third micro electromagnetic relay is released, the first micro electromagnetic relay and the third micro electromagnetic relay cooperate to complete the measurement of the AC leakage current;

[0035] When the first micro electromagnetic relay is attracted, the second micro electromagnetic relay is attracted, and the third micro electromagnetic relay is attracted, the first micro electromagnetic relay, the second micro electromagnetic relay, and the third micro electromagnetic relay cooperate to complete the measurement of the DC leakage current.

[0036] Further, the protection unit includes three gas discharge tubes, three varistors, three bidirectional TVS diodes, a first sampling resistor, and a second sampling resistor. The first gas discharge tube, the first varistor, and the first bidirectional TVS diode are connected in series and then connected in parallel with the AC leakage generation circuit. The second gas discharge tube, the second varistor, and the second bidirectional TVS diode are connected in series and then connected in parallel with the DC leakage generation circuit. The first sampling resistor and the second sampling resistor are both connected in parallel across both ends of the high-voltage pulse capacitor. The second sampling resistor is connected in parallel with the third gas discharge tube. The third varistor and the third bidirectional TVS diode are connected in series and then connected in parallel with the second sampling resistor;

[0037] The resistance value of the first sampling resistor is greater than that of the second sampling resistor.

[0038] Further, the distance between the high-voltage devices and the low-voltage devices in the power supply, the current output unit, the current generation control unit, the anti-interference unit, and the protection unit is greater than 10 mm. The wires through which the impact current flows in the power supply, the current output unit, the current generation control unit, the anti-interference unit, and the protection unit are all made of silicone wires with a withstand voltage level of more than 30 kV. Grooves are opened in the set area around the high-voltage devices.

[0039] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0040] A lightning arrester calibration system provided by the present invention realizes power isolation protection by setting different circuits in the power supply to generate different currents, ensures that the currents used in different tests during lightning arrester calibration are isolated from each other, avoids interference between the impact current test and the leakage test, and at the same time, the high voltage generated during the test is completely isolated from the externally provided AC power supply; by setting the anti-interference unit, it prevents other currents from flowing through the lightning arrester during a certain test, ensuring that the test is not interfered by other currents; by setting the protection unit, it prevents the impact current from damaging the lightning arrester calibration system and the power grid. The present invention reduces the influence of the high voltage and large current generated by the impact current test on the operator, the lightning arrester calibration system, and the power supply line through the above means, and ensures personal safety, the safety of the power supply grid, and the normal operation of the lightning arrester calibration system. Description of the Drawings

[0041] Figure 1 It is a schematic diagram of a lightning arrester calibration system provided by Embodiment 1 of the present invention;

[0042] Figure 2 It is a schematic circuit diagram of calibration using the lightning arrester calibration system provided by Embodiment 2 of the present invention. Specific Embodiments

[0043] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0044] Embodiment 1

[0045] This embodiment provides a lightning arrester calibration system, including: a power supply, a current output unit, a current generation control unit, an anti-interference unit, and a protection unit;

[0046] The power supply is used to generate the current required for lightning arrester calibration and output the generated current to the current output unit. There is no connection between the circuits for generating any two kinds of currents in the power supply. The currents include impulse current, leakage current, and measurement and control current;

[0047] The current output unit is used to control the output of the current, and the current generation control unit is used to control the process of the power supply generating the current;

[0048] The anti-interference unit is connected to the power supply and is used to disconnect the path of the power supply outputting the leakage current during the impulse current test, and isolate the input of the circuit for generating the impulse current in the power supply during the leakage current test;

[0049] The protection unit is used to shunt the impulse current during the impulse current test, and is also used to absorb and store the residual high voltage in the circuit when switching from the impulse current test to the leakage current test.

[0050] The present invention realizes power supply isolation protection by setting different circuits in the power supply to generate different currents, ensures that the currents used in different tests during lightning arrester calibration are isolated from each other, avoids mutual interference between the impulse current test and the leakage test, and at the same time, the high voltage generated during the test is completely isolated from the externally provided AC power supply; by setting the anti-interference unit to prevent other currents from flowing through the lightning arrester during a certain test, ensuring that the test is not interfered by other currents; by setting the protection unit to prevent the impulse current from damaging the lightning arrester calibration system and the power grid. The present invention reduces the influence of the high voltage and large current generated by the impulse current test on the operator, the lightning arrester calibration system, and the power supply line through the above means, and ensures personal safety, the safety of the power supply grid, and the normal operation of the lightning arrester calibration system.

[0051] Embodiment 2

[0052] This embodiment provides a lightning arrester calibration system, which includes a power supply, a current output unit, a current generation control unit, an anti-interference unit, a protection unit, and a leakage current measurement and control unit.

[0053] In the power supply, power supply isolation is achieved by means of transformer power supply isolation protection. Specifically, different circuits are set in the power supply to generate different currents to achieve power supply isolation.

[0054] In order to achieve power supply isolation during the impulse current test, an impulse current generation circuit is set in the power supply. The impulse current generation circuit includes a power supply unit, an AC220V to AC8kV high-voltage pulse transformer, a bridge rectifier, and a high-voltage pulse capacitor. The process of generating an impulse current in the impulse current generation circuit is as follows: The current provided by the power supply unit is converted into an AC high voltage by the AC220V to AC8kV high-voltage pulse transformer and then transmitted to the bridge rectifier. The bridge rectifier converts the AC high voltage into a DC high voltage and transmits it to the high-voltage pulse capacitor. The DC high voltage charges the high-voltage pulse capacitor. When the high-voltage pulse capacitor is charged under the action of the DC high voltage, an impulse current is generated.

[0055] In order to achieve power supply isolation during the impulse current test, a first measurement and control current generation circuit is set in the power supply. The first measurement and control current generation circuit is a power supply unit and an AC220V to AC12V power transformer. The AC220V to AC12V power transformer converts the current provided by the power supply unit into a first measurement and control current. The first measurement and control current is a power supply for high-voltage measurement and control, that is, the measurement and control current used during the impulse current test using the impulse current.

[0056] In order to achieve power isolation during the leakage current test, an AC leakage current generation circuit, a second measurement and control current generation circuit, a DC leakage current generation circuit, and a third measurement and control current generation circuit are provided in the power supply; the AC leakage current generation circuit is a power supply unit and an AC220V to AC220V transformer, and this AC220V to AC220V transformer converts the current provided by the power supply unit into an AC leakage current; the second measurement and control current generation circuit is a power supply unit and an AC220V to AC9V transformer, and this AC220V to AC9V transformer converts the current provided by the power supply unit into a second measurement and control current, and the second measurement and control current is the measurement and control current used for the AC leakage current test when using the AC leakage current; the DC leakage current generation circuit is a power supply unit and a DC220V to DC220V transformer, and this DC220V to DC220V transformer converts the current provided by the power supply unit into a DC leakage current; the third measurement and control current generation circuit is a power supply unit and a DC220V to DC9V transformer, and this DC220V to DC9V transformer converts the current provided by the power supply unit into a third measurement and control current, and the third measurement and control current is the measurement and control current used for the DC leakage current test when using the DC leakage current.

[0057] Through the above design of the power supply, it is ensured that the impulse current, AC leakage current, and DC leakage current used in the impulse current test and the leakage current test are all isolated from each other, avoiding interference between the impulse current test and the leakage current test, and at the same time, the high voltage generated during the test is completely isolated from the externally provided AC power supply.

[0058] The current output unit and the current generation control unit protect the lightning arrester calibration system and the power grid where the lightning arrester is located through the method of relay contact isolation protection.

[0059] The high-voltage reed relay has a set of switching contacts, with good contact isolation performance and high-voltage switching characteristics. The isolation voltage between its contacts is above 10kV, and the high-voltage reed relay can be used to control the external output switching of the high-voltage impulse current or leakage current. To improve the withstand voltage energy of the contacts, suppress the generation of arcs, and extend the contact life, in the high-voltage reed relay, the normally open contact and the normally closed contact are sealed in an environment filled with inert gas.

[0060] The current output unit includes two high-voltage reed relays and two self-locking switches. Each high-voltage reed relay includes a normally open contact, a normally closed contact, a common terminal, and a coil. In any one high-voltage reed relay, the normally open contact and the normally closed contact are located inside the coil;

[0061] When controlling the output of the current, in the current output unit, one end of two normally open contacts is respectively connected to the positive and negative electrodes of the high-voltage pulse capacitor, one normally closed contact is connected to the live wire of the AC leakage current output terminal and the positive electrode of the DC leakage current output terminal in the power supply, and the other normally closed contact is connected to the neutral wire of the AC leakage current output terminal and the negative electrode of the DC leakage current output terminal in the power supply. The two coils are connected in parallel, one end of the coil is grounded, and the other end is connected to the common terminal of the self-locking switch; the self-locking switch controls the suction and release of the high-voltage reed relay through the coil. When the high-voltage reed relay is in the suction state, the normally open contact is conducted with the common terminal, and the impact current is output; when the high-voltage reed relay is in the release state, the normally closed contact is in the conduction state with the common terminal, and the leakage current is output.

[0062] The high-voltage vacuum relay has the characteristics of high switching ability, high relay ability, high anti-interference ability, etc., and can be used for the control, protection and isolation of large currents in high-voltage circuits. When the normally open contact of the high-voltage vacuum relay discharges in a vacuum, unlike in air, when the high-voltage gap distance is less than the distance corresponding to the air insulation voltage, the phenomenon of discharge arcing will occur, interfering with the normal operation of other nearby components and causing abnormal operation of the equipment. The high-voltage vacuum relay has a set of changeover contacts.

[0063] The insulation strength varies greatly with different air temperature and humidity. When the voltage is 10 kV, the distance corresponding to the air insulation voltage is 1 - 10 mm. In this embodiment, the distance corresponding to the air insulation voltage is taken as 10 mm.

[0064] The current generation control unit includes a high-voltage vacuum relay and a manual key switch. The high-voltage vacuum relay is used to control the process of the power supply generating the impact current. The high-voltage vacuum relay includes a normally open contact, a common terminal and a coil; when controlling the power supply to generate current, in the current generation control unit, the normally open contact is connected to the positive electrode of the high-voltage pulse capacitor in the above-mentioned impact current generation circuit, the common terminal is connected to the negative electrode of the high-voltage pulse capacitor in the above-mentioned impact current generation circuit, one end of the high-voltage vacuum relay coil is grounded, and the other end is connected to a DC 12V power supply through the manual key switch. When conducting the impact current test, after the high-voltage pulse capacitor is fully charged, press the manual key switch in the current generation control unit. The coil in the high-voltage vacuum relay is energized, and its normally open contact is sucked and conducted in a vacuum. The high-voltage pulse capacitor discharges in a short circuit, instantly generating a large current (because the energy stored in the high-voltage pulse capacitor is limited and the energy is quickly exhausted and ends). When the manual key switch is released, the high-voltage vacuum relay loses power and its normally open contact disconnects. The contacts of the high-voltage vacuum relay are in a near-vacuum environment and will not produce arcing discharge phenomena, which can extend the service life of the contacts and reduce the impact of arcing on surrounding devices.

[0065] The Hongfa HF115F electromagnetic relay has two sets of changeover contacts, with a contact switching capacity of 16A. The dielectric withstand voltage between the coil and the contacts is 5kV, and the creepage distance is 10mm, meeting the requirements of reinforced insulation in the VDE0700 / 0631 standard. The power supplies for the impulse current test and the leakage current test are respectively controlled by the two sets of contacts of the electromagnetic relay with a working voltage of DC 5V, avoiding the mutual interference between the impulse current and the leakage current.

[0066] The anti-interference unit includes an electromagnetic relay, a self-locking switch, and a manual push-button switch. The electromagnetic relay includes a normally open contact, a normally closed contact, a common terminal, and a coil; in this embodiment, the electromagnetic relay is the Hongfa HF115F electromagnetic relay.

[0067] In the anti-interference unit, one end of the normally open contact is connected to the live wire of the power supply outside the arrester calibration system. The common terminal is connected to the live wire of the primary side of the AC220V to AC8kV high-voltage pulse transformer through one end of the manual push-button switch. One end of the normally closed contact is connected to the live wire of the secondary side of the transformer in the AC leakage current generation unit or the DC leakage current generation unit. The self-locking switch is connected to the coil; the self-locking switch controls the attraction and release of the Hongfa HF115F electromagnetic relay through the coil. During the impulse current test, after pressing the self-locking switch, the Hongfa HF115F electromagnetic relay is controlled to be in the attracted state through the self-locking switch. The other ends of the normally open contact and the common terminal are in contact, carrying AC220V electricity. The other end of the manual push-button switch is connected to the live wire of the primary side of the AC220V to AC8kV high-voltage pulse transformer. After pressing the manual push-button switch, at this time, there is an AC220V input on the primary side of the AC220V to AC8kV high-voltage pulse transformer, and the secondary side of the AC220V to AC8kV high-voltage pulse transformer outputs an AC high voltage. The AC high voltage is rectified by a bridge rectifier and then outputs a DC high voltage. The DC high voltage charges the high-voltage pulse capacitor, and then the high-voltage pulse capacitor outputs an impulse current. The other ends of the normally closed contact and the common terminal are in the open state (because the Hongfa HF115F electromagnetic relay is in the attracted state at this time), and at this time, the power supply does not output leakage current, avoiding the interference of leakage current during the impulse current test; during the leakage current test, after the self-locking switch is released, the Hongfa HF115F electromagnetic relay is controlled to be in the released state through the self-locking switch. The other ends of the normally closed contact and the common terminal are in contact. At this time, the AC leakage current generation circuit outputs an AC leakage current or the DC leakage current generation circuit outputs a DC leakage current, and at this time, there is no input on the primary side of the AC220V to 8kV high-voltage pulse transformer, and an impulse current cannot be generated. The impulse current generation circuit does not output an impulse current, avoiding the accidental generation of an impulse current during the leakage current test and causing harm to the operator.

[0068] The leakage current measurement and control unit is used to control and measure the AC leakage current and DC leakage current generated by the power supply; the leakage current measurement and control unit includes a self-locking switch, two AC measurement current-limiting resistors, two DC measurement current-limiting resistors, a first micro electromagnetic relay, a second micro electromagnetic relay, and a third micro electromagnetic relay. The components of the first micro electromagnetic relay, the second micro electromagnetic relay, and the third micro electromagnetic relay are the same, and each includes a coil, two normally open contacts, two normally closed contacts, and a common terminal. The three coils are connected in parallel and are all connected to the self-locking switch. The self-locking switch controls the energization and release of the first micro electromagnetic relay, the second micro electromagnetic relay, and the third micro electromagnetic relay through the three coils respectively. In this embodiment, the first micro electromagnetic relay, the second micro electromagnetic relay, and the third micro electromagnetic relay are all Hongfa HFD27 micro electromagnetic relays. The Hongfa HFD27 micro electromagnetic relay has 2 sets of changeover contacts, adopts a bifurcated contact form, and has a switching capacity of 125VA / 60W. Through the relay for switching the AC leakage current and the DC leakage current, the output of the AC leakage current and the DC leakage current is controlled to avoid the mutual interference between the AC leakage current and the DC leakage current.

[0069] On the first micro electromagnetic relay, the two common terminals are respectively connected to the adjustable end and the zero line end of the adjustable potentiometer connected to the secondary side of the transformer in the AC leakage current generation circuit. The two normally open contacts are respectively connected to the input terminals of the bridge rectifier. One normally closed contact is connected to the live wire of the AC leakage current output terminal and the positive pole of the DC leakage current output terminal in the power supply, and the other normally closed contact is connected to the zero line of the AC leakage current output terminal and the negative pole of the DC leakage current output terminal in the power supply. When the first micro electromagnetic relay is released, it is used to assist in measuring the AC leakage current; when the first micro electromagnetic relay is energized, it is used to assist in measuring the DC leakage current.

[0070] On the second micro electromagnetic relay, the two normally open contacts are respectively connected to the output terminals of the bridge rectifier, the two normally closed contacts are left floating, one common terminal is connected to the live wire of the AC leakage current output terminal and the positive pole of the DC leakage current output terminal in the power supply, and the other common terminal is connected to the zero line of the AC leakage current output terminal and the negative pole of the DC leakage current output terminal in the power supply; when the second micro relay is energized, it is used to assist in measuring the DC leakage current.

[0071] On the third micro electromagnetic relay, the two normally closed contacts are respectively connected to the two AC measurement current-limiting resistors for measuring the AC leakage current. The two normally open contacts are respectively connected to the two DC measurement current-limiting resistors. The two common terminals are connected to both ends of the input of the ammeter for measuring the leakage current.

[0072] When the first micro electromagnetic relay is released and the third micro electromagnetic relay is released, the first micro electromagnetic relay and the third micro electromagnetic relay cooperate to complete the measurement of the AC leakage current;

[0073] When the first micro electromagnetic relay is closed, the second micro electromagnetic relay is closed, and the third micro electromagnetic relay is closed, the first micro electromagnetic relay, the second micro electromagnetic relay, and the third micro electromagnetic relay cooperate to complete the measurement of the AC leakage current.

[0074] The protection unit includes three gas discharge tubes, three varistors, three bidirectional TVS diodes, a first sampling resistor, and a second sampling resistor. The first gas discharge tube, the first varistor, and the first bidirectional TVS diode are connected in series and then connected in parallel with the AC leakage generation circuit. The second gas discharge tube, the second varistor, and the second bidirectional TVS diode are connected in series and then connected in parallel with the DC leakage generation circuit. The first sampling resistor and the second sampling resistor are both connected in parallel across the high-voltage pulse capacitor. The second sampling resistor is connected in parallel with the third gas discharge tube. The third varistor and the third bidirectional TVS diode are connected in series and then connected in parallel with the second sampling resistor.

[0075] In this embodiment, the gas discharge tube is a 90V10kA gas discharge tube, which can limit the voltage within 90V and has a maximum current-carrying capacity of 10kA; the varistor is a 10D471K varistor, where 10 represents that the diameter of the zinc oxide varistor ceramic chip in the varistor is 10mm, and 471 represents that the varistor voltage value is 470V; the bidirectional TVS diode is a SIMBJ6.5CA bidirectional TVS diode, its package form is SMB, the breakdown voltage is 6.5V, and the peak power is 600W.

[0076] Through the circuit design of the protection unit, that is, by connecting a 90V10kA gas discharge tube, a 10D471K varistor, and a SIMBJ6.5CA bidirectional TVS diode in parallel on the output leakage circuit, the interference of the high voltage generated during the impulse current test to the components in the circuit is reduced. At the same time, the residual high voltage when switching from the impulse current test to the leakage current test is also reduced, preventing the residual high voltage from being conducted to the leakage current generation circuit and the leakage current measurement and control circuit. Through the circuit design of the protection unit, that is, by connecting the first sampling resistor and the second sampling resistor in parallel across the high-voltage pulse capacitor, high-voltage sampling is realized. A high-voltage large-value resistor (referring to the first sampling resistor) and a small-value metal film resistor (referring to the second sampling resistor) are used for voltage division sampling. A gas discharge tube is connected in parallel across the metal film resistor. At the same time, the varistor and the bidirectional TVS diode are connected in series and then connected in parallel with the metal film resistor. The gas discharge tube, the varistor, and the bidirectional TVS diode absorb the high voltage to reduce the situation where the impulse current generated during the impulse current test is conducted to the impulse current measurement circuit.

[0077] In this embodiment, all high-voltage devices on the equipment are kept away from other devices by more than 10mm to reduce the spatial interference between the high-voltage devices and other devices.

[0078] In this embodiment, all wires connected to the impulse current use silicone wires with a withstand voltage level of more than 30 kV to minimize the impact of high-voltage impulse current on other components.

[0079] In this embodiment, the mounting base plate of the device, and between the panel and the base plate, insulating phenolic boards are used for isolation protection at the same time. Devices that are relatively close are isolated by grooving to isolate the impact of high-voltage devices on other devices.

[0080] Combined Figure 2 , the process of generating impulse current by the lightning arrester calibration system provided in this embodiment is described. As Figure 2 shown, the live wire L of the power socket J1 is connected to one end of the primary side of the step-down transformer T2 through the rocker switch S2. The live wire L of the power socket J1 is also connected to a common terminal of one group of the Hongfa HF115F electromagnetic relays K1 used for converting AC leakage current / DC leakage current. The neutral wire N of the power socket J1 is directly connected to the other ends of the primary sides of the high-voltage pulse transformer T1 and the step-down transformer T2. One end of the button S1 is connected to the normally open contact of one group of contacts of the Hongfa HF115F electromagnetic relay K1, and the other end of the button S1 is connected to one end of the primary side of the high-voltage pulse transformer T1.

[0081] The step-down transformer T2 is used to provide a 12V DC power supply, and the step-down transformer T2 provides a working power supply for the components used to perform the impulse current test in the lightning arrester calibration system.

[0082] In Figure 2 , the high-voltage pulse transformer T1 is a high-voltage pulse transformer that converts AC220V to AC8kV.

[0083] One end of the secondary side of the high-voltage pulse transformer T1 is connected to one end of the high-power resistor R1. The other end of the resistor R1 is connected to the positive electrode of the high-voltage rectifier diode D1. The negative electrode of the high-voltage rectifier diode D1 is respectively connected to one ends of the high-voltage pulse capacitors CHV1, CHV2, the resistor R2, and the high-power aluminum shell resistor RJ1. The other end of the secondary side of the high-voltage pulse transformer T1 is connected to the negative electrode of the high-voltage rectifier diode D2. The positive electrode of the high-voltage rectifier diode D2 is connected to the other ends of the high-voltage pulse capacitors CHV1 and CHV2. The positive electrode of the high-voltage rectifier diode D2 is also connected to one end of the resistor R3, one end of the varistor RY1, and the high-voltage terminal N / -. The high-voltage pulse capacitors CHV1 and CHV2 are connected in parallel, and the total capacitance is doubled. The high-voltage pulse capacitors CHV1 and CHV2 are voltage-divided by the high-power resistor R2 and the resistor R3. The gas discharge tube F1 and the varistor RY1 are connected in series and then connected in parallel across both ends of the resistor R3 for the high-voltage measurement and display unit to sample, which can effectively prevent the high-voltage sampling voltage from being too high and damaging the high-voltage measurement unit.

[0084] The illuminated self-locking switch S3 has two sets of contacts. The common terminal of one set of contacts is connected to the 5V power supply. The normally open contact is connected to one end of the coil of the Hongfa HF115F electromagnetic relay K1, which is used for controlling the power supply of the high-voltage pulse transformer by the AC 220V input power supply or isolating the output of the 220V power supply. The common terminal of the other set of contacts is connected to the 12V power supply. The normally open contact is connected to one end of the coils of the high-voltage reed relay K2 and the relay K3, which is used for controlling the output of the impact current or leakage current. The normally open contact of this set is connected to the positive pole of the indicator light of the illuminated self-locking switch S3, and the negative pole of the indicator light is connected to the ground of the 12V power supply. The other end of the coil of the Hongfa HF115F electromagnetic relay K1 is connected to the ground of the power supply of the 220V leakage current generation and leakage current monitoring DC power transformer T3. The other ends of the coils of the relays K2 and K3 are connected to the ground of the power supply of the step-down transformer T2.

[0085] One end of the high-power aluminum shell resistor RJ1 is respectively connected to the high-voltage pulse capacitors CHV1 and CHV2. The other end is connected in series with the high-power spring resistor RL1, and then connected to the normally open contact of the high-voltage vacuum relay K4. The common terminal of the high-voltage vacuum relay K4 is connected to the high-voltage terminal L / +. The negative poles of the high-voltage pulse capacitors CHV1 and CHV2 are connected to the high-voltage terminal N / -.

[0086] The two ends of the secondary side of the step-down transformer T2 are respectively connected to the two AC input terminals of the bridge rectifier U1. The positive output terminal of the bridge rectifier U1 is connected to the positive poles of the filter capacitors C1 and C2 and the input terminal of the three-terminal voltage regulator U2. The negative output terminal of the bridge rectifier U1 is connected to the negative poles of the filter capacitors C1 and C2 and the grounding terminal of the three-terminal voltage regulator U2. The output terminal of the three-terminal voltage regulator U2 is connected to the positive poles of the filter capacitors C5 and C6, and the negative poles of the filter capacitors C5 and C6 are grounded.

[0087] The coil of the high-voltage vacuum relay K4 is controlled by the push-button switch S4. One end of the push-button switch S4 is connected to the 12V DC power supply, and the other end is connected to one end of the coil of the high-voltage vacuum relay K4. The other end of the coil of the high-voltage vacuum relay K4 is grounded.

[0088] When the power socket J1 is powered on and the boat-type switch S2 is turned on, the step-down transformer T2 is powered on and works, outputting a stepped-down voltage. After being rectified by the bridge rectifier U1, it generates an unregulated DC 12V power supply. After being filtered by the filter capacitors C1 and C2, regulated by the three-terminal voltage regulator U2, and filtered again by the filter capacitors C5 and C6, a stable 5V DC power supply is obtained.

[0089] Press the two - group conversion self - locking switch S3 with an indicator light. The pin L1 of the conversion self - locking switch S3 conducts with the normally - open contact, obtaining a 12V DC voltage, while the pin L2 of the conversion self - locking switch S3 is grounded, and the indicator light of the conversion self - locking switch S3 lights up. At the same time, the 3 - foot and 2 - foot of the normally - open contact of the conversion self - locking switch S3 conduct, and the coil of the Hongfa HF115F electromagnetic relay K1 obtains a 5V power supply. The coil of the Hongfa HF115F electromagnetic relay K1 is energized and attracted, and one end of the push - button switch S1 conducts with the live wire L of the AC220V power supply. The 4 - foot of the conversion self - locking switch S3 is disconnected, and the coils of the relay K2 and the relay K3 lose the 12V power supply, and their normally - open contacts are disconnected, and the leakage measurement circuit is disconnected. In this embodiment of the Figure 2 wherein, 1, 2, 3, 4, 5, and 6 respectively represent the 1 - foot, 2 - foot, 3 - foot, 4 - foot, 5 - foot, and 6 - foot of the self - locking switch S3.

[0090] Press the push - button switch S1, the primary side of the high - voltage pulse transformer T1 obtains AC220V and starts to work, outputting a high - voltage AC power supply. After the high - voltage AC power supply is limited by the high - power resistor R1, it is rectified by the half - wave rectification composed of the high - voltage rectifier diode D1 and the high - voltage rectifier diode D2 to charge the high - voltage pulse capacitors CHV1 and CHV2. The charging voltage gradually increases, and the time from 0V to full charge is 5RC. In this embodiment, it takes 20s. The charging voltage is divided by the high - power resistor R2 and the metal - film resistor R3, and the sampled voltage is connected across the metal - film resistor R3. To prevent high - voltage impact, the gas discharge tube F1 and the varistor RV1 are connected in series and then connected across the resistor R3, and then detected by the high - voltage measurement and display unit CN1. When the voltage value of the high - voltage measurement and display unit CN1 reaches the desired magnitude, release the push - button switch S1 to stop charging the high - voltage pulse capacitors CHV1 and CHV2. In this way, a high - voltage charging process is completed.

[0091] When the push - button switch S4 is pressed, the coil of the high - voltage vacuum relay K4 obtains a 12V power supply and is attracted. The high - voltage electricity flows from the high - voltage pulse capacitors CHV1 and CHV2 through the high - power aluminum - shell resistor RJ1 and the high - power spring resistor RL1 and is output to the monitored arrester device. The normally - open contact of the high - voltage vacuum relay K4 is connected to the high - voltage terminal. As a result, the monitored device is subjected to a high - voltage impact. Since the arrester monitoring device is similar to MOA oxide, the resistance value changes non - linearly with the voltage. For the part higher than its withstand voltage, the resistance value is close to zero ohm, generating a shock wave similar to 8 / 20μs, and its counter operates due to the high - voltage impact. The high - voltage pulse capacitors CHV1 and CHV2 discharge due to the high - voltage, and the stored energy is quickly exhausted until it drops below a few hundred V of the remaining residual voltage.

[0092] Combined with Figure 2, the process of generating AC leakage, DC leakage, and performing leakage verification for the lightning arrester verification system provided in this embodiment is described. Based on the above wiring of the AC power supply, the other end of the boat-shaped switch S2 is also connected to one end of the primary side of the transformer T3. One set of outputs of the transformer T3 is connected to the AC input terminal of the rectifier bridge U3. The output terminal of the rectifier bridge U3 is connected to the positive poles of the filter capacitors C7 and C8 and the input terminal of the three-terminal voltage regulator U4. The negative pole of the rectifier bridge U3 is grounded; the 5V output terminal of the three-terminal voltage regulator is connected to the positive poles of the filter capacitors C9 and C10, and the negative pole of the three-terminal voltage regulator is grounded; the other set of outputs of the transformer T3 is a 220V isolated power supply, and its two ends are respectively connected to the two ends of the adjustable potentiometer R4. The middle tap of the adjustable potentiometer R4 is connected to the common terminal of another set of contacts of the Hongfa HF115F electromagnetic relay K1. The normally closed contact of this set of contacts is connected to the normally closed contact of a set of contacts of the relay K5, and the normally closed contact of another set of contacts of the relay K5 is connected to the other end of the output isolated 220V voltage in the secondary side of the transformer T3.

[0093] The two groups of conversion self-locking switches S5 with indicator lights control the switching between AC leakage and DC leakage during verification. The coil power supplies of the electromagnetic relay K5, relay K6, and relay K7 are controlled by the push-button switch S5. Figure 2 In [description], S represents the connection points of the push-button switch S5, electromagnetic relay K5, relay K6, and relay K7. The two-way AC power supplies output by the adjustable potentiometer R4 (both output through the interface ACX1) are connected to the two normally closed contacts of the electromagnetic relay K5. The two-way AC power supplies output by the adjustable potentiometer R4 are also connected to the two AC input terminals of the bridge rectifier U6; the two output terminals of the bridge rectifier U6 are filtered by the filter capacitor C11 and then connected to the two normally open contacts of the electromagnetic relay K5 (connected through the interface DCX+ and interface DCX-); the common terminal (interface XL1 and interface XL2) of the relay K6 is connected to the common terminal (interface XL1 and interface XL2) of the relay K5. The normally open contact of the relay K6 is connected to the common terminal of the relay K2 through the resistor R8 (connected through the interface XLO2, and the common terminal of the relay K2 is the interface XL-L), and the normally open contact of the relay K6 is connected to the common terminal of the relay K3 through the resistor R9 (connected through the interface XLO1, and the common terminal of the relay K3 is the interface XL-N); the resistor R8 is connected in parallel with the gas discharge tube F2, and the resistor R9 is connected in parallel with the gas discharge tube F3, which is used to absorb the residual high voltage due to the impulse current test and the high voltage impact when switching to leakage verification; the normally open contact of the relay K2 is connected to the high voltage terminal L / +, and the normally open contact of the relay K3 is connected to the high voltage terminal N / -.

[0094] When the two - group transfer self - locking switch S5 with an indicator pops up, the indicator light goes out; the relays K5, K6, and K7 are released; the two common terminals of the relay K5 are respectively connected to the middle tap of the adjustable potentiometer R4 and the neutral line of the isolated AC220V output by the transformer T3. The two common terminals of the relay K5 are connected to the middle tap of the adjustable potentiometer R4 through the interfaces ACX1 and ACX2. The two common terminals of the relay K6 are respectively in conduction with the normally - closed contacts; at this time, there is 12V DC on the coils of the relays K2 and K3. The common terminal of the relay K2 is in conduction with the normally - open contact, and the common terminal of the relay K3 is in conduction with the normally - open contact. The common terminals of the relays K2 and K3 are also respectively in conduction with the high - voltage terminal L / + and the high - voltage terminal N / -, outputting an alternating current to the monitored lightning arrester monitoring device. By adjusting the knob of the adjustable potentiometer R4, the magnitude of the leakage current is changed. The loop for outputting the leakage current is also in series with the relay K7. When K7 is released, the alternating leakage current passes through the bridge rectifier U5 to convert the alternating current into a direct current, and then is input into the leakage current measurement and display unit CN2. The sampling and display value is adjusted through the resistors R6 and R7. By comparing the leakage current measurement and display unit CN2 with the indicated value of the device under test, the error of the device under test is determined.

[0095] The two output terminals of the bridge rectifier U5 are filtered by the filter capacitor C12, and the filter capacitor C12 is in parallel with the resistor R17.

[0096] When the two - group transfer self - locking switch S5 with an indicator is pressed, the indicator light is on, and the relays K5, K6, and K7 are attracted; the two common terminals of the relay K5 are respectively in conduction with the normally - open contacts, and the DC voltage rectified by the rectifier bridge U6 is connected to the normally - open contacts of the relay K5. The common terminal of the relay K5 outputs a DC voltage; the two normally - open contacts of the relay K6 are respectively in conduction with the common terminal; at this time, there is still 12V on the coils of the high - voltage vacuum relays K2 and K3. The common terminals of the high - voltage vacuum relays K2 and K3 are respectively in conduction with the normally - open contacts, and the common terminals of the high - voltage vacuum relays K2 and K3 are also in conduction with the high - voltage terminals, outputting a direct current to the monitored lightning arrester monitoring device. By adjusting the knob of the adjustable potentiometer R4, the magnitude of the leakage current is changed. The loop for outputting the leakage current is also in series with the relay K7. When the relay K7 is attracted, the direct current passes through the bridge rectifier U5 for rectification again (the relay K7 and the bridge rectifier U5 are connected through the interfaces INA+ and INA -), and is input into the leakage current measurement and display unit CN2. The relay K7 and the leakage current measurement and display unit CN2 are connected through the interfaces INB+ and INB -. The sampling and display value is adjusted through the resistors R5 and R7. By comparing the leakage measurement and display unit CN2 with the indicated value of the device under test, the error of the device under test is determined.

[0097] In this embodimentFigure 2 Among them, the resistance value of resistor R1 is 1 MΩ, the resistance value of resistor R2 is 80 MΩ, the resistance value of resistor R3 is 330 Ω, the resistance value of resistor RJ1 is 1 Ω, the resistance value of resistor RL1 is 10 Ω. The capacitance of high-voltage pulse capacitors CHV1 and CHV2 is 1 μF, the rated voltage is 10 kV. The capacitance of capacitor C1 is 1000 μF, the capacitance of capacitor C2 is 100 nF, the capacitance of capacitor C5 is 1000 μF, the capacitance of capacitor C6 is 100 nF, the capacitance of capacitor C7 is 1000 μF, the capacitance of capacitor C8 is 100 nF, the capacitance of capacitor C9 is 1000 μF, the capacitance of capacitor C10 is 100 nF. IN represents the input terminal, OUT represents the output terminal, GND represents the common terminal, AC indicates that the current flowing through this port is an alternating current, 5VH represents a high level of 5 volts, and GNDH represents the common terminal of the high level.

[0098] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of the present invention, several improvements and deformations can be made, and these improvements and deformations should also be regarded as the protection scope of the present invention.

Claims

1. A lightning arrester calibration system, characterized in that: include: Power supply, current output unit, current generation control unit, anti-interference unit, protection unit; The power supply is used to generate the current required for arrester calibration and output the generated current to the current output unit, and the circuits generating different currents in the power supply are not connected to each other, and the currents include impact current, leakage current and measurement and control current; The current output unit is used to control the output of the current, and the current generation control unit is used to control the process of the power supply generating current; The anti-interference unit is connected to the power supply and is used to disconnect the path of the leakage current output by the power supply during the impulse current test, and to isolate the input of the circuit for generating the impulse current in the power supply during the leakage current test; The protection unit is used to shunt the impulse current during the impulse current test, and is also used to absorb and store the residual high voltage in the circuit when switching from the impulse current test to the leakage current test; The power supply includes an impact current generating circuit, a first measurement and control current generating circuit, an AC leakage current generating circuit, a second measurement and control current generating circuit, a DC leakage current generating circuit and a third measurement and control current generating circuit; The arrester inspection includes impulse current test, AC leakage current test and DC leakage current test; The impulse current generating circuit is used to generate the impulse current required for lightning arrester calibration; The first measurement and control current generating circuit is used to generate the first measurement and control current required in the arrester calibration, and the first measurement and control current is the measurement and control current used when the impulse current is used to perform an impulse current test; The AC leakage generating circuit is used to generate the AC leakage current required for lightning arrester calibration; The second measurement and control current generating circuit is used to generate a second measurement and control current required for lightning arrester calibration, and the second measurement and control current is a measurement and control current used when performing an AC leakage current test using the AC leakage current; The DC leakage current generating circuit is used to generate the DC leakage current required for lightning arrester calibration; The third measurement and control current generating circuit is used to generate the third measurement and control current required in the arrester calibration, and the third measurement and control current is the measurement and control current used when the DC leakage current is used to perform the DC leakage current test; The impulse current generating circuit comprises a power supply unit, an AC high-voltage pulse transformer, a bridge rectifier and a high-voltage pulse capacitor connected in sequence, wherein the AC high-voltage pulse transformer is used to convert the current provided by the power supply unit into an AC high voltage and transmit it to the bridge rectifier, the bridge rectifier is used to convert the AC high voltage into a DC high voltage and transmit it to the high-voltage pulse capacitor, and the high-voltage pulse capacitor is used to store the energy of the impulse current generated by the DC high voltage and output the impulse current; The first measurement and control current generating circuit, the AC leakage current generating circuit, the second measurement and control current generating circuit, the DC leakage current generating circuit and the third measurement and control current generating circuit are connected to different transformers for power supply units respectively; The anti-interference unit includes an electromagnetic relay, a self-locking switch and a manual key switch, and the electromagnetic relay includes a normally open contact, a normally closed contact, a common terminal and a coil; In the anti-interference unit, the common end is connected to the live wire of the power supply outside the arrester calibration system, the normally open contact is connected to the live wire of the primary side of the AC high-voltage pulse transformer, the normally closed contact is connected to the live wire of the secondary side of the transformer in the AC leakage current generating circuit or the DC leakage circuit generating circuit, one end of the coil is connected to the self-locking switch, and the other end of the coil is grounded; The electromagnetic relay is controlled to be attracted and released by the self-locking switch. During the impact current test, the self-locking switch is pressed, the electromagnetic relay is in the attracted state, the normally open contact and the common terminal are in the on state, at this time the high-voltage pulse capacitor outputs impact current, the normally closed contact and the common terminal are in the off state, and the power supply does not output leakage current; during the leakage current test, the self-locking switch is popped up, the electromagnetic relay is in the released state, the normally closed contact and the common terminal are on, at this time the AC leakage current generating circuit outputs AC leakage current or the DC leakage current generating circuit outputs DC leakage current, and the impact current generating circuit does not output impact current.

2. The arrester calibration system according to claim 1, characterized in that: The current output unit includes two high-voltage reed switch relays and a self-locking switch, each of the high-voltage reed switch relays includes a normally open contact, a normally closed contact, a common terminal and a coil; When controlling the output of current, in the current output unit, two normally open contacts are respectively connected to the positive and negative poles of the impulse current output terminal in the power supply, one normally closed contact is connected to the live wire of the AC leakage current output terminal and the positive pole of the DC leakage current output terminal in the power supply, and another normally closed contact is connected to the neutral wire of the AC leakage current output terminal and the negative pole of the DC leakage current output terminal in the power supply. The common terminal is used to output the current flowing through the high-voltage reed switch relay. The two coils are connected in parallel and controlled by a self-locking switch. When the self-locking switch is turned on, the high-voltage reed switch coil is energized and attracted. At this time, the normally open contact is connected to the common terminal, and the impact current provided by the power supply is output through the common terminal; when the self-locking switch is turned off, the high-voltage reed switch coil loses power and is released. At this time, the normally closed contact is connected to the common terminal, and the AC leakage current or DC leakage current provided by the power supply is output through the common terminal.

3. The lightning arrester calibration system according to claim 1, characterized in that: The current generation control unit is an impact current generation control unit, including a resistor R1, a high-voltage vacuum relay and a manual key switch. The high-voltage vacuum relay is used to control the high-voltage pulse capacitor to generate an impact current using the DC high voltage stored in the capacitor. The high-voltage vacuum relay includes a normally open contact, a common terminal and a coil. In the impulse current generation control unit, the normally open contact is connected in series with the resistor R1, and then connected to the positive electrode of the high-voltage pulse capacitor, the common end is connected to the negative electrode of the high-voltage pulse capacitor, one end of the coil is grounded, and the other end is connected to a DC power supply through a manual key switch; When the manual push button switch is turned on, the high-voltage vacuum relay coil is energized and its normally open contact is instantly short-circuited with the common terminal.

4. The arrester calibration system according to claim 1, characterized in that: Also included is a leakage measurement and control unit, the leakage measurement and control unit is used to control and measure the AC leakage current and the DC leakage current generated by the power supply; The leakage measurement and control unit includes an ammeter, an adjustable potentiometer, a self-locking switch, two AC measurement current limiting resistors, two DC measurement current limiting resistors, a first micro-electromagnetic relay, a second micro-electromagnetic relay and a third micro-electromagnetic relay. The first micro-electromagnetic relay, the second micro-electromagnetic relay and the third micro-electromagnetic relay have the same components, including a coil, two normally open contacts, two normally closed contacts and two common terminals. The three coils are connected in parallel and are all connected to the self-locking switch. The self-locking switch controls the attraction and release of the first micro-electromagnetic relay, the second micro-electromagnetic relay and the third micro-electromagnetic relay respectively through the three coils. On the first micro electromagnetic relay, the adjustable potentiometer is connected to the secondary side of the transformer in the AC leakage current generating circuit, the two common terminals are respectively connected to the adjustable terminal and the neutral terminal of the adjustable potentiometer, the two normally open contacts are respectively connected to the two input terminals of the bridge rectifier, a normally closed contact is connected to the live wire of the AC leakage current output terminal and the positive pole of the DC leakage current output terminal in the power supply, and the other normally closed contact is connected to the neutral wire of the AC leakage current output terminal and the negative pole of the DC leakage current output terminal in the power supply; On the second micro electromagnetic relay, two normally open contacts are respectively connected to two output terminals of the bridge rectifier, two normally closed contacts are suspended, one common terminal is connected to the live wire of the AC leakage current output terminal and the positive pole of the DC leakage current output terminal in the power supply, and the other common terminal is connected to the neutral wire of the AC leakage current output terminal and the negative pole of the DC leakage current output terminal in the power supply; On the third micro electromagnetic relay, two normally closed contacts are respectively connected to two AC measuring current limiting resistors for measuring AC leakage current, two normally open contacts are respectively connected to two DC measuring current limiting resistors, and two common terminals are connected to both ends of the ammeter input; When the first micro-electromagnetic relay is released, and the third micro-electromagnetic relay is released, the first micro-electromagnetic relay and the third micro-electromagnetic relay cooperate to complete the measurement of the AC leakage current; When the first micro-electromagnetic relay is energized, the second micro-electromagnetic relay is energized, and the third micro-electromagnetic relay is energized, the first micro-electromagnetic relay, the second micro-electromagnetic relay and the third micro-electromagnetic relay cooperate to complete the measurement of the DC leakage current.

5. The lightning arrester calibration system according to claim 1, characterized in that: The protection unit includes three gas discharge tubes, three varistors, three bidirectional TVS diodes, a first sampling resistor and a second sampling resistor. The first gas discharge tube, the first varistor and the first bidirectional TVS diode are connected in series and connected in parallel with the AC leakage generation circuit. The second gas discharge tube, the second varistor and the second bidirectional TVS diode are connected in series and connected in parallel with the DC leakage generation circuit. The first sampling resistor and the second sampling resistor are both connected in parallel at both ends of the high-voltage pulse capacitor. The second sampling resistor is connected in parallel with the third gas discharge tube. The third varistor and the third bidirectional TVS diode are connected in series and connected in parallel with the second sampling resistor. The resistance value of the first sampling resistor is greater than the resistance value of the second sampling resistor.

6. The arrester calibration system according to claim 1, characterized in that: The distance between the high-voltage devices and the low-voltage devices in the power supply, current output unit, current generation control unit, anti-interference unit, and protection unit is greater than 10 mm. The wires through which the impact current flows are made of silicone wire with a withstand voltage rating of 30 kV or above, and grooves are opened in the set area around the high-voltage devices.

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