Dielectric recovery characteristic measuring device and measuring method thereof

Abstract

Disclosed is a dielectric recovery characteristic measuring device, in which a test main circuit comprises a switch sample to be tested, a high-power power supply for simulating a disconnection fault to be tested, and a timing control module for switching on and off and applying a high-voltage pulse according to a set time sequence; a resistor-capacitor module is connected to the test main circuit, and the resistor-capacitor module comprises a high-voltage energy storage capacitor, a discharge resistor, an upper bridge arm current limiting resistor, and a lower bridge arm current limiting resistor; a high-voltage direct current power supply is connected to the resistor-capacitor module and charges the high-voltage energy storage capacitor; a high-voltage switch is connected to the high-voltage direct current power supply and the resistor-capacitor module; a semiconductor switch is connected to the resistor-capacitor module; a control module is connected to the semiconductor switch and sends a driving signal to switch on and off according to set parameters, thereby forming a pulse applied to the switch sample to be tested; an industrial computer is connected to the high-voltage switch and the control module, and the industrial computer adjusts parameters and outputs the control module, controls the switching on and off of the high-voltage switch and the output of the high-voltage direct current power supply, and monitors the measurement process.

Description

Technical Field

[0001] The invention relates to the field of switch electrical appliance performance testing, in particular to a dielectric recovery characteristic measuring device and a measuring method thereof. Background Art

[0002] In recent years, DC power distribution systems have attracted extensive attention due to their excellent performance in renewable energy integration, system expansion, and improving grid stability. DC breaking technology, as a protection technology for grid faults, has also made great progress. However, since the DC power distribution system is a low-damping system, the short-circuit current can rise to tens of kiloamperes in a very short time. In order to enable the short-circuit current to quickly pass through zero and be cut off, the transfer current usually has a very high current change rate, which will result in a large amount of metal vapor and plasma generated between the contacts during the arcing stage after the short-circuit current quickly passes through zero. The rapid rise in the recovery voltage at both ends of the contacts will produce corresponding electrical and thermal effects. If the dielectric insulation strength of the switch test piece cannot withstand the recovery voltage, the circuit breaker will undergo post-arc breakdown, and the short-circuit current will rise rapidly again, resulting in a breaking failure.

[0003] At present, the dielectric recovery characteristics are all tested by a high-voltage power supply that outputs a single pulse. In order to obtain the complete post-arc dielectric recovery characteristics, this method needs to repeat the experiment many times while ensuring that other conditions remain unchanged and only changing the pulse output time. However, in the actual test process, it is difficult to achieve completely consistent test conditions for each experiment, resulting in a large dispersion of test results, so the test efficiency is low and the test results have a large dispersion. At the same time, since this test requires adding high-voltage pulses to both ends of the switch test piece after the current passes through zero, it is necessary to design a complex synchronous control so that the output time of the high-voltage pulse can be accurately controlled. In addition, the pulse high-voltage power supply currently widely used for post-arc dielectric recovery characteristics measurement is a traditional Marx circuit. The pulse triggering time is difficult to accurately control, and its waveform parameters such as pulse width, rise and fall time, and duty cycle are also difficult to accurately adjust. At the same time, it has a high cost, large volume and weight, low system efficiency, and cannot guarantee service life, stability and reliability. The output pulse waveform is also prone to change, which greatly limits its scope of application.

[0004] The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art. Summary of the invention

[0005] In view of the deficiencies or defects in the above-mentioned prior art, a dielectric recovery characteristic measuring device and a measuring method thereof are provided, which overcome the defects and deficiencies of the existing dielectric recovery characteristic measuring devices, can form a stable, accurate and efficient pulse waveform, and optimize the measurement experiment process.

[0006] The object of the present invention is achieved through the following technical solutions. After the switch is disconnected, the air and SF 6 The recovery of the insulation properties of dielectrics such as insulating gases and vacuum is a process. The breakdown voltage that the insulating medium in the switch test piece withstands is called the dielectric recovery strength. The changing characteristics of the dielectric recovery strength during the recovery process are the dielectric recovery characteristics of the switch.

[0007] The dielectric recovery characteristic measuring device includes:

[0008] A test main circuit, which includes a switch test piece under test, a high-power power supply for providing energy for an arc between electrodes of the switch test piece under test, and a timing control module for opening the switch and applying a high-voltage pulse between the electrodes according to a set time sequence;

[0009] A resistance-capacitance module is connected to the test main circuit, and the resistance-capacitance module includes a high-voltage energy storage capacitor, a discharge resistor, an upper bridge arm current limiting resistor, and a lower bridge arm current limiting resistor. The high-voltage energy storage capacitor outputs a pulse to the switch sample under test through the upper bridge arm current limiting resistor, and the switch sample under test releases the residual voltage through the lower bridge arm current limiting resistor, and the capacitor releases the remaining energy through the discharge resistor;

[0010] A high-voltage direct current power supply, connected to the RC module and charging the high-voltage energy storage capacitor;

[0011] A high-voltage switch, which is connected to the high-voltage DC power supply and the RC module, and the high-voltage switch controls the charging of the high-voltage energy storage capacitor by the high-voltage DC power supply and the discharging of the high-voltage energy storage capacitor to the discharge resistor;

[0012] A semiconductor switch connected to the RC module, the semiconductor switch is turned on and off at high frequency to control the pulse discharge of the high-voltage energy storage capacitor to apply a pulse voltage to the switch sample under test and release the residual voltage;

[0013] A control module is connected to the semiconductor switch and sends a drive signal to switch it on and off according to the waveform parameters, thereby forming a pulse applied to the switch sample under test. The control module stores and processes parameters and controls the overall communication and operation of the device.

[0014] The dielectric recovery characteristic measuring device also includes an industrial computer, and the parameters adjusted by the industrial computer include the voltage amplitude, pulse period, pulse width, pulse number and time delay of the high-voltage pulse.

[0015] In the dielectric recovery characteristic measuring device, the high-voltage energy storage capacitor and the discharge resistor, and the high-voltage energy storage capacitor and the upper bridge arm current limiting resistor are insulated by a liquid medium or a solid medium.

[0016] In the dielectric recovery characteristic measuring device, the liquid medium includes insulating oil, and the solid medium includes epoxy material.

[0017] In the dielectric recovery characteristic measuring device, the voltage of the high-voltage energy storage capacitor is measured by a voltmeter.

[0018] The dielectric recovery characteristic measuring device also includes an industrial computer, which is connected to the control module via optical fiber communication and is electrically isolated from the control module. The power supply of the control module is also isolated from the mains and is equipped with a metal shielding box.

[0019] In the dielectric recovery characteristic measuring device, the control module is electrically isolated from the mains and is equipped with a metal shielding box.

[0020] In the dielectric recovery characteristic measuring device, the high-power power supply includes a capacitor or a charger.

[0021] In the dielectric recovery characteristic measuring device, the charging process of the high-voltage direct current power supply to the high-voltage energy storage capacitor is constant current and constant power.

[0022] The measuring method of the dielectric recovery characteristic measuring device comprises the following steps:

[0023] Set the voltage amplitude, pulse period, pulse width, pulse number and time delay of the high voltage pulse and transmit them to the control module.

[0024] The high-voltage switch is controlled so that the charging switch is closed and the discharging switch is opened. The high-voltage DC power supply charges the high-voltage energy storage capacitor in the RC module.

[0025] After charging is completed, the test main circuit conducts current flow and disconnection of the switch under test, and the timing control module sends a trigger signal. After receiving the signal, the control module sends a drive signal to the semiconductor switch. The semiconductor switch controls the high-voltage energy storage capacitor pulse discharge at high frequency to make it switch on and off according to the set parameters, thereby forming a pulse applied to the switch under test.

[0026] The high-voltage DC power supply in this article is a DC power supply of kilovolts or above. The high-voltage switching power supply in this article is a high-voltage switch of kilovolts or above. The high-power power supply in this article is a high-power power supply of kilowatts or above. The high-voltage pulse in this article is a high-voltage pulse of kilovolts or above. The high-voltage energy storage capacitor in this article is a high-voltage energy storage capacitor of kilovolts or above.

[0027] Beneficial Effects

[0028] The present invention utilizes a high-frequency switch to control the discharge of a capacitor, and can continuously output multiple high-voltage pulses in one experiment, thereby obtaining a complete dielectric recovery characteristic curve, and the parameters such as amplitude, period, and pulse width are adjustable, the output pulse has high stability, and the energy storage capacitor charges quickly, thereby saving a large amount of experimental test time, reducing the repetition rate of the experiment, and improving the efficiency of the dielectric recovery characteristic measurement test. All operations of the device can be performed in the industrial computer it is matched with, all equipment is encapsulated in a cabinet, the shell is grounded, and there is sufficient isolation between the operator and the equipment of the high-voltage part, which has good safety and convenience. The control module has no electrical connection with other parts, and the communication between the control module and the industrial computer is transmitted through optical fiber, the power supply is isolated from the mains, and a metal shielding box is installed, thereby improving the anti-interference ability of the control module, and also protecting precision instruments such as high-voltage half-bridge push-pull switches.

[0029] The above description is only an overview of the technical solution of the present invention. In order to make the technical means of the present invention clearer and to enable those skilled in the art to implement it according to the contents of the specification, and to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described below by way of example. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] By reading the detailed description of the preferred specific embodiments below, various other advantages and benefits of the present invention will become clear to those of ordinary skill in the art. The drawings in the specification are only for the purpose of illustrating the preferred embodiments and are not considered to be limitations of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative work. Moreover, the same reference numerals are used to represent the same components throughout the drawings.

[0031] In the attached picture:

[0032] Figure 1 A schematic structural diagram of an embodiment of a dielectric recovery characteristic measuring device of the present invention;

[0033] Figure 2 A schematic diagram of the circuit principle of an embodiment of a dielectric recovery characteristic measuring device of the present invention;

[0034] Figure 3 A parameter setting interface of the onboard operating software of an embodiment of the medium recovery characteristic measuring device of the present invention;

[0035] Figure 4 It is a working timing diagram of each device of an embodiment of the dielectric recovery characteristic measuring device of the present invention;

[0036] Figures 5(a) and 5(b) are schematic diagrams of dielectric recovery characteristic curves obtained by experiment of an embodiment of a dielectric recovery characteristic measuring device of the present invention, wherein Figure 5(a) is a local enlarged view of the experimental waveform, and Figure 5(b) is a local enlarged view of the output pulse. DETAILED DESCRIPTION

[0037] The following will refer to the attached Figure 1 to Figure 5(b) Specific embodiments of the present invention are described in more detail. Although specific embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0038] It should be noted that certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that technicians may use different nouns to refer to the same component. This specification and claims do not use the difference in nouns as a way to distinguish components, but use the difference in the functions of the components as the criterion for distinction. As mentioned throughout the specification and claims, "including" or "comprising" is an open term, so it should be interpreted as "including but not limited to". The subsequent description of the specification is a preferred embodiment of the present invention, but the description is based on the general principles of the specification and is not intended to limit the scope of the present invention. The scope of protection of the present invention shall be determined by the attached claims.

[0039] To facilitate understanding of the embodiments of the present invention, several specific embodiments will be further explained below with reference to the accompanying drawings, and each of the accompanying drawings does not constitute a limitation on the embodiments of the present invention.

[0040] like Figure 1 , Figure 2 As shown, the dielectric recovery characteristic measuring device includes:

[0041] The test main circuit includes a switch test product under test, a high-power power supply of kilowatt level or above for providing energy for the arc between the electrodes of the test product, and energy storage devices such as capacitors, and a timing control module 6 for opening the switch according to a set time sequence and applying a high-voltage pulse of kilovolt level or above between the electrodes;

[0042] A resistance-capacitance module 1 is connected to the test main circuit. The resistance-capacitance module 1 includes a high-voltage energy storage capacitor of kilovolt level or above, a discharge resistor, an upper bridge arm current limiting resistor, and a lower bridge arm current limiting resistor. The high-voltage energy storage capacitor outputs a pulse to the switch sample under test through the upper bridge arm current limiting resistor. The switch sample under test releases the residual voltage through the lower bridge arm current limiting resistor, and the capacitor releases the remaining energy through the discharge resistor;

[0043] A high-voltage direct current power supply 2 of kilovolt level or above, which is connected to the resistor-capacitor module 1 and charges the high-voltage energy storage capacitor;

[0044] A high-voltage switch 3 of kilovolt level or above, which is connected to the high-voltage DC power supply 2 and the resistor-capacitor module 1, and the high-voltage switch 3 controls the charging of the high-voltage energy storage capacitor by the high-voltage DC power supply 2 and the discharging of the high-voltage energy storage capacitor to the discharge resistor;

[0045] A semiconductor switch 4 connected to the RC module 1, the semiconductor switch 4 is turned on and off at high frequency to control the pulse discharge of the high-voltage energy storage capacitor to apply a pulse voltage to the switch sample under test and release the residual voltage;

[0046] A control module 6, which is connected to the semiconductor switch 4 and sends a drive signal to switch it on and off according to the waveform parameters, thereby forming a pulse applied to the switch sample under test, and the control module 6 stores and processes the parameters and controls the overall communication and operation of the device;

[0047] The industrial computer 5 is connected to the high-voltage switch 3 and the control module 6. The industrial computer 5 inputs waveform parameters through onboard operation and outputs them to the control module 6, controls the on and off of the high-voltage switch 3 and the output of the high-voltage DC power supply 2, and monitors the measurement process.

[0048] In the preferred embodiment of the dielectric recovery characteristic measuring device, the parameters adjusted by the industrial computer 5 include the voltage amplitude, pulse period, pulse width, pulse number and time delay of the high voltage pulse.

[0049] In a preferred embodiment of the dielectric recovery characteristic measuring device, the high-voltage energy storage capacitor and the discharge resistor, and the high-voltage energy storage capacitor and the upper bridge arm current limiting resistor are insulated by a liquid medium or a solid medium.

[0050] In a preferred embodiment of the dielectric recovery characteristic measuring device, the liquid medium includes insulating oil, and the solid medium includes epoxy material.

[0051] In a preferred embodiment of the dielectric recovery characteristic measuring device, the voltage of the high-voltage energy storage capacitor is measured using a voltmeter.

[0052] In the preferred embodiment of the dielectric recovery characteristic measuring device, the industrial computer 5 and the control module 6 are connected via optical fiber communication and are electrically isolated from each other. The power supply of the control module 6 is also isolated from the mains and is equipped with a metal shielding box.

[0053] In a preferred embodiment of the dielectric recovery characteristic measuring device, the control module 6 is electrically isolated from the mains and is equipped with a metal shielding box.

[0054] In a preferred embodiment of the dielectric recovery characteristic measuring device, the high-power power supply includes a capacitor or a charger.

[0055] In a preferred embodiment of the dielectric recovery characteristic measuring device, the charging process of the high-voltage DC power supply 2 on the high-voltage energy storage capacitor is constant current and constant power.

[0056] In one embodiment, the RC module 1, high-voltage DC power supply 2, high-voltage switch 3, semiconductor switch 4, industrial computer 5, control module 6, and test main circuit are arranged in an electrical cabinet.

[0057] In one embodiment, the RC module 1 includes a high-voltage energy storage capacitor, a discharge resistor, and two current-limiting resistors; the high-voltage DC power supply 2 is used to charge the high-voltage energy storage capacitor in the RC module 1, and the charging process is constant current / constant power; the high-voltage relay serves as a charging switch and a discharging switch, and is used to control the charging of the high-voltage energy storage capacitor in the RC module 1 by the high-voltage DC power supply 2, and the discharge of the high-voltage energy storage capacitor to the discharge resistor; the semiconductor switch 4 can control the pulse discharge of the capacitor in the RC module 1 by high-frequency on-off, so as to realize the application of pulse voltage and the release of residual voltage on the switch sample under test in the test main circuit; the industrial computer 5 has operating software, which can set the parameters of the output pulse, and control and monitor the experimental process; the control module 6 is responsible for storing parameter information, realizing communication between various parts, controlling the overall operation of the device according to the received parameters, and displaying the operating status through the operating software loaded by the industrial computer; the test main circuit includes the switch sample under test, a high-power power supply, and a timing control module 6. Preferably, the capacitor in the RC module 1 outputs a pulse to the switch sample under test through the upper bridge arm current limiting resistor, the switch sample under test releases the residual voltage through the lower bridge arm current limiting resistor, and the capacitor releases the remaining energy through the discharge resistor; preferably, the capacitor and the resistor in the RC module 1 are insulated by a liquid medium such as insulating oil or a solid medium of epoxy material. Preferably, the voltage of the capacitor in the RC module 1 can be measured using a voltmeter using the voltage division principle. Preferably, the two high-voltage switches 3 in the device can be controlled to be on and off by the industrial computer 5, and the working status can be monitored. Preferably, the industrial computer 5 and the control module 6 communicate through optical fiber, and the two are electrically isolated. The power supply of the control module 6 is also isolated from the main power supply, and a metal shielding box is installed to reduce the interference of external factors on the main control board. Preferably, the high-power power supply in the test main circuit, which is an energy storage device such as a capacitor or a charger, simulates a fault condition for the switch sample under test, and the timing control module 6 performs disconnection and application of high-voltage pulses according to the set time sequence.

[0058] In one embodiment, a dielectric recovery characteristic measuring device includes a resistor-capacitor module 1, a high-voltage direct current power supply 2, two high-voltage switches 3, a semiconductor switch 4, an industrial computer 5, and a control module 6; wherein the resistor-capacitor module 1 includes a high-voltage energy storage capacitor, a discharge resistor, and two current-limiting resistors; the high-voltage direct current power supply 2 is used to charge the high-voltage energy storage capacitor in the resistor-capacitor module, and the charging process is constant current / constant power, and an anti-parallel diode is installed at the output port of the high-voltage direct current power supply 2 for protection; the high-voltage switch 3 is used as a charging switch and a discharging switch to control the high-voltage direct current power supply 2 to charge the high-voltage energy storage capacitor in the resistor-capacitor module 1, and the high-voltage energy storage capacitor to discharge the discharge resistor; the energy storage capacitor uses a voltage divider principle The semiconductor switch 4 can realize the application of pulse voltage and the release of residual voltage on the switch sample under test in the test main circuit by measuring the small voltage; the industrial computer 5 has operation software, and the user can enter the parameter value in the space corresponding to each parameter in the setting interface of the software and click OK, so as to set the parameters of the output pulse and control and monitor the experimental process; the control module is responsible for storing and processing parameter information, communication between various parts, and overall operation of the control device; the test main circuit includes the switch sample under test, a high-power power supply, and a timing control module. In addition, the various components and parameters of the above-mentioned device are more optimized. For example, the current limiting resistor in the resistor-capacitor module 1 selects a suitable value, taking into account the pulse rise rate and the influence of the pulse current on the dielectric recovery. The capacitor and the resistor are insulated by a liquid medium such as insulating oil or a solid medium of epoxy material. The voltage of the high-voltage energy storage capacitor uses the voltage division principle to measure the large voltage on the energy storage capacitor by measuring the small voltage, and it is displayed by a digital tube. The industrial computer 5 adjusts the pulse parameters, can control the output of the high-voltage DC power supply 2, can control the on and off of the high-voltage switch 3, and can communicate with the main control board through optical fiber, and has better anti-interference performance.

[0059] Combine the following Figure 2 , Figure 3 , Figure 4 The principle of the above device is described in detail. Figure 2 As shown. Figure 3 Input the pulse parameters, pulse voltage, pulse period, pulse width, number of pulses, delay time, into the operating software of the industrial computer 5 shown in the figure, and click the parameter save button to send the data to the high-voltage DC power supply 2 and the control module 6. When the device is ready, charging can be started, and testing can be carried out after charging is completed. After the experiment starts, the test main circuit is as follows Figure 3The set timing controls the switch sample under test to pass current and open, and then sends a trigger signal to the control module 6, thereby driving the semiconductor switch 4 to switch on and off at the set frequency, generating a high-voltage pulse to be applied to the switch sample under test.

[0060] The control module 6 is isolated from the high-voltage side and the mains power by an isolation transformer, and the main control board communicates with the industrial computer 5 by optical fiber to ensure that the control part has better stability and anti-interference performance; the capacitor voltage is monitored at any time by a digital tube to avoid uninformed live operation.

[0061] In order to more effectively demonstrate the advantages of the present invention, the inventors conducted experimental tests on the above device, and the results are shown in Figures 5(a) and 5(b). About 600μs after the arc was extinguished, 5 pulses were continuously generated on the switch sample under test, with a period of 105μs and a pulse width of 5μs. It can be seen from Figures 5(a) and 5(b) that each time a pulse was generated, the pulse voltage was less than the capacitor voltage, that is, the five pulses broke through the switch sample, and its dielectric recovery strength gradually increased. By connecting the highest point of each pulse, an approximate dielectric recovery strength characteristic curve can be obtained.

[0062] The measuring method of the dielectric recovery characteristic measuring device comprises the following steps:

[0063] The industrial computer 5 sets the voltage amplitude, pulse period, pulse width, pulse number and time delay of the high voltage pulse and transmits them to the control module 6.

[0064] The industrial computer 5 controls the high-voltage switch 3 so that the charging switch is closed and the discharging switch is opened, and the high-voltage DC power supply 2 charges the high-voltage energy storage capacitor in the resistor-capacitor module 1.

[0065] After charging is completed, the test main circuit conducts current flow and disconnection of the switch under test, and the timing control module 6 sends a trigger signal. After receiving the signal, the control module 6 sends a drive signal to the semiconductor switch 4. The semiconductor switch 4 controls the pulse discharge of the high-voltage energy storage capacitor at high frequency, so that it is switched on and off according to the set parameters, thereby forming a pulse applied to the switch under test.

[0066] Under normal working conditions, the voltage amplitude, pulse period, pulse width, number of pulses, and time delay of the high-voltage pulse are set in the industrial computer 5, and the data is transmitted to the control module 6 after being saved. Then, the high-voltage switch 3 is controlled in the industrial computer 5 so that the charging switch is closed and the discharging switch is disconnected. At the same time, the high-voltage DC power supply 2 charges the high-voltage energy storage capacitor in the resistor-capacitor module 1. After charging is completed, the main circuit of the test is tested to pass and disconnect the switch sample under test, and the timing control module 6 sends a trigger signal. After receiving the signal, the control module 6 sends a drive signal to the semiconductor switch 4 to make it switch on and off according to the set parameters, thereby forming a pulse applied to the switch sample under test.

[0067] Although the embodiments of the present invention are described above in conjunction with the accompanying drawings, the present invention is not limited to the above specific embodiments and application fields, and the above specific embodiments are only illustrative and instructive, rather than restrictive. A person of ordinary skill in the art can also make many forms under the guidance of this specification and without departing from the scope of protection of the claims of the present invention, all of which belong to the protection of the present invention.

Claims

1. A dielectric recovery characteristic measuring device, characterized in that: These include, A test main circuit, which includes a switch test piece under test, a high-power power supply for providing energy for an arc between electrodes of the switch test piece under test, and a timing control module for opening the switch and applying a high-voltage pulse between the electrodes according to a set time sequence; A resistance-capacitance module is connected to the test main circuit, and the resistance-capacitance module includes a high-voltage energy storage capacitor, a discharge resistor, an upper bridge arm current limiting resistor, and a lower bridge arm current limiting resistor. The high-voltage energy storage capacitor outputs a pulse to the switch sample under test through the upper bridge arm current limiting resistor, and the switch sample under test releases the residual voltage through the lower bridge arm current limiting resistor, and the capacitor releases the remaining energy through the discharge resistor; A high-voltage direct current power supply, connected to the RC module and charging the high-voltage energy storage capacitor; A high-voltage switch, which is connected to the high-voltage DC power supply and the RC module, and the high-voltage switch controls the charging of the high-voltage energy storage capacitor by the high-voltage DC power supply and the discharging of the high-voltage energy storage capacitor to the discharge resistor; A semiconductor switch connected to the RC module, the semiconductor switch is turned on and off at high frequency to control the pulse discharge of the high-voltage energy storage capacitor to apply a pulse voltage to the switch sample under test and release the residual voltage; A control module is connected to the semiconductor switch and sends a drive signal to switch it on and off according to the waveform parameters, thereby forming a pulse applied to the switch sample under test. The control module stores and processes the parameters and controls the overall communication and operation of the device.

2. The dielectric recovery characteristic measuring device according to claim 1, characterized in that: Preferably, the device further comprises an industrial computer, and the waveform parameters adjusted by the industrial computer include the voltage amplitude, pulse period, pulse width, pulse number and time delay of the high voltage pulse.

3. The dielectric recovery characteristic measuring device according to claim 1, characterized in that: The high-voltage energy storage capacitor and the discharge resistor, as well as the high-voltage energy storage capacitor and the upper bridge arm current limiting resistor are insulated by a liquid medium or a solid medium.

4. The dielectric recovery characteristic measuring device according to claim 3, characterized in that: Liquid media include insulating oil, and solid media include epoxy materials.

5. The dielectric recovery characteristic measuring device according to claim 1, characterized in that: The voltage of the high-voltage energy storage capacitor is measured by a voltmeter.

6. The dielectric recovery characteristic measuring device according to claim 1, characterized in that: The device includes an industrial computer, which is connected to a control module via optical fiber communication and is electrically isolated from the control module. The power supply of the control module is also isolated from the mains power and is equipped with a metal shielding box.

7. The dielectric recovery characteristic measuring device according to claim 1, characterized in that: The control module is electrically isolated from the mains and is equipped with a metal shielding box.

8. The dielectric recovery characteristic measuring device according to claim 1, characterized in that: The high power source includes a capacitor or a charger.

9. The dielectric recovery characteristic measuring device according to claim 8, characterized in that: The charging process of the high-voltage direct current power supply to the high-voltage energy storage capacitor is constant current and constant power.

10. The measuring method of the dielectric recovery characteristic measuring device according to any one of claims 1 to 9, characterized in that: It includes the following steps: Setting the voltage amplitude, pulse period, pulse width, pulse number and time delay of the high voltage pulse and transmitting them to the control module; The high-voltage switch is controlled so that the charging switch is closed and the discharging switch is opened, and the high-voltage DC power supply charges the high-voltage energy storage capacitor in the RC module; After charging is completed, the test main circuit conducts current flow and disconnection of the switch under test, and the timing control module sends a trigger signal. After receiving the signal, the control module sends a drive signal to the semiconductor switch. The semiconductor switch controls the high-voltage energy storage capacitor pulse discharge at high frequency to make it switch on and off according to the set waveform parameters, thereby forming a pulse applied to the switch under test.

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