CN110736922A - Device and method for measuring switch closing pre-breakdown time - Google Patents

Abstract

The invention relates to the technical field of high-voltage switchgear and high-voltage electrical appliances, in particular to a device and method for measuring the closing pre-breakdown time of a switch. The method uses a DC voltage generating device to load a set voltage value at both ends of the grounding switch to be tested to control the closing of the grounding switch to be tested; obtain the travel signals before and after the grounding switch to be tested is closed, and obtain the first time corresponding to the change of the travel signal obtain the voltage signal at both ends of the grounding switch to be tested, and obtain the second time point corresponding to the jump of the voltage signal; determine the pre-breakdown time according to the difference between the first time point and the second time point. The start time of the pre-breakdown time is determined by obtaining the stroke change of the grounding switch to be tested, and the termination time of the pre-breakdown time is determined by monitoring the voltage jump of the grounding switch to be tested, so that the pre-breakdown time can be accurately obtained. Technically, the calculation of pre-breakdown time is more accurate, simpler and more reliable.

Description

Device and method for measuring switch closing pre-breakdown time

technical field

The invention relates to the technical field of high-voltage switchgear and high-voltage electrical appliances, in particular to a device and method for measuring the closing pre-breakdown time of a switch.

Background technique

With the development of UHV transmission technology, more and more attention has been paid to the safety and reliability of UHV transmission systems. Due to the complexity of the power grid system, the requirements for power grid system equipment are getting higher and higher. How to strictly evaluate the power grid The performance reliability of medium and high voltage electrical appliances is very important. At present, the pre-breakdown time is generally determined by the closing test of the GIS (gas-insulated combined electrical appliance) grounding switch. In the test, the capacitor tower is used for high-voltage discharge, but the existing closing test has the following shortcomings:

1) High-voltage discharge is performed on the grounding switch through the capacitor tower. Due to the high closing voltage, the requirements for the test circuit are high, the requirements for circuit equipment are high, the cost is high, and there is a certain test risk;

2) The pre-breakdown time is determined only by monitoring the change of the voltage at both ends of the grounding switch, but the accuracy of the pre-breakdown time is low, and the accuracy and reliability are poor.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a device and method for measuring the closing pre-breakdown time of a switch, so as to solve the problem of inaccurate detection of the pre-breakdown time of the existing grounding switch.

In order to achieve the above purpose, the present invention provides a method for measuring the closing pre-breakdown time of a switch, comprising the following steps:

1) Load the set voltage value on both ends of the grounding switch to be tested through the DC voltage generating device to control the closing of the grounding switch to be tested;

2) Obtain the travel signal before and after the grounding switch to be tested is closed, and obtain the first time point corresponding to the start of the change of the travel signal;

3) Obtain the voltage signal at both ends of the grounding switch to be tested, and obtain the second time point corresponding to the jump of the voltage signal;

4) Determine the pre-breakdown time according to the difference between the first time point and the second time point.

The beneficial effect is that the starting time of the pre-breakdown time is determined by obtaining the stroke change of the grounding switch to be tested, and the termination time of the pre-breakdown time is determined by monitoring the voltage jump of the grounding switch to be tested, so that the pre-breakdown time can be accurately obtained, Compared with the prior art, the calculation of the pre-breakdown time is more accurate, simpler and more reliable.

Further, in order to realize the generation of the set voltage value simply and safely, the DC voltage generating device is an impulse voltage generator. The impulse voltage generator is used to directly apply a short-term voltage to both ends of the grounding switch to be tested, which has lower requirements for the test loop and loop equipment, which reduces the cost. Compared with the use of capacitor towers and other equipment, the test risk is great. reduce.

The invention provides a device for measuring the closing pre-breakdown time of a switch. The measuring device includes a DC voltage generating device, a voltage sampling device, a travel sensor, a processor and an opening and closing drive device;

The DC voltage generating device is used for loading a set voltage value at both ends of the grounding switch to be tested;

The voltage sampling device is used to collect the voltage signal at both ends of the grounding switch to be tested;

The travel sensor is used to collect the travel signal of the grounding switch to be tested;

The output end of the opening and closing driving device is used to connect the grounding switch to be tested, so as to realize the closing operation of the grounding switch to be tested;

The first input end of the processor is connected to the voltage sampling device, the second input end of the processor is connected to the stroke sensor, and the processor obtains the first time point and the voltage signal jump corresponding to the start of the stroke signal change. Change the corresponding second time point, and use the time difference between the first time point and the second time point as the pre-breakdown time.

The beneficial effect is that the starting time of the pre-breakdown time is determined by obtaining the stroke change of the grounding switch to be tested, and the termination time of the pre-breakdown time is determined by monitoring the voltage jump of the grounding switch to be tested, so that the pre-breakdown time can be accurately obtained, Compared with the prior art, the calculation of the pre-breakdown time is more accurate, simpler and more reliable.

Further, in order to improve the safety of the test and the accuracy of signal collection, the travel sensor is connected to the second input end of the processor through the first electro-optical converter, the first optical fiber and the first electro-optical converter in sequence.

Further, in order to improve the safety and control accuracy of the test test, the output end of the opening and closing driving device is used to connect the grounding switch to be tested through a second electro-optical converter, a second optical fiber, and a second optical-electrical converter in sequence.

Further, in order to directly observe the test results, the voltage sampling device and the stroke sensor are also connected with an oscilloscope.

Further, in order to easily monitor the voltage, the voltage sampling device is a resistor divider.

Further, in order to realize simple and safe control of the opening and closing of the grounding switch, the opening and closing driving device is a mechanical characteristic tester.

Further, in order to realize the generation of the set voltage value simply and safely, the DC voltage generating device is an impulse voltage generator. The impulse voltage generator directly applies a short-term voltage to both ends of the grounding switch to be tested, which has lower requirements on the test loop and loop equipment, which reduces the cost. Compared with the use of capacitor towers and other equipment, the test risk is great. reduce.

Description of drawings

1 is a schematic diagram of a method for measuring the closing pre-breakdown time of a GIS grounding switch of the present invention;

2 is a schematic diagram of the composition of a measuring device for the closing pre-breakdown time of a GIS grounding switch according to the present invention;

In the figure, 1 is an impulse voltage generator, 2 is a resistive voltage divider, 3 is a GIS grounding switch, 4 is a stroke sensor, 5 is a first electro-optical converter, 6 is a first photoelectric converter, 7 is a processor, and 8 is a is the second photoelectric converter, 9 is the second photoelectric converter, and 10 is the mechanical characteristic tester.

Detailed ways

The switch of the present invention takes the GIS grounding switch as an example, and the present invention is further described in detail with reference to the accompanying drawings.

Method example:

The invention provides a method for measuring the closing pre-breakdown time of a GIS grounding switch, comprising the following steps:

1) Load the set voltage value on both ends of the grounding switch to be tested through the impulse voltage generator to control the closing of the grounding switch to be tested.

The impulse voltage generator is essentially a DC voltage generating device, which can generate a certain voltage according to the demand. The set voltage value is greater than 100kV. As other implementations, the impulse voltage generator can also use other existing voltage generators. replace.

2) Obtain the travel signal before and after the grounding switch to be tested is closed, and obtain the first time point corresponding to the start of the change of the travel signal.

The travel of the GIS grounding switch and the corresponding time data can be monitored by the travel sensor. As another implementation, monitoring can also be realized by other sensors capable of detecting position, such as a displacement sensor and a position sensor.

3) Obtain the voltage signal at both ends of the grounding switch to be tested, and obtain the second time point corresponding to the jump of the voltage signal.

Since the two ends of the GIS grounding switch are loaded with voltage, the voltage across the two ends of the GIS grounding switch can be safely detected through the resistor divider. The resistor divider is essentially a voltage sampling device. Other voltage detection devices implement voltage monitoring.

4) Determine the pre-breakdown time according to the difference between the first time point and the second time point.

As shown in Figure 1, below the time t axis is the stroke curve of the GIS grounding switch to be tested monitored by the stroke sensor. When the stroke signal starts to change, the first time point corresponding to the stroke signal starting to change is: t ₀ , the time difference between t ₀ and t ₂ is the closing time.

Above the time t axis is the loaded voltage signal curve monitored by the resistor divider, U ₁ represents the set voltage value, after the first time point t ₀ , if the voltage signal jumps, the voltage signal jumps The second time point corresponding to the change is t ₁ , which is the breakdown point at time t ₁ , when the voltage begins to drop, and the time difference between t ₀ and t ₁ is read as the closing pre-breakdown time.

Device Example 1:

The present invention provides a measuring device for closing pre-breakdown time of a GIS grounding switch, and the measuring device is a device structure capable of realizing the above measuring method.

As shown in Figure 2, the measuring device includes an impulse voltage generator 1, a resistance voltage divider 2, a travel sensor 4, a processor 7 and a mechanical characteristic tester 10; the positive and negative electrodes of the impulse voltage generator 1 are connected to the GIS grounding switch 3 Both ends are used to generate a short-term set voltage value; the resistor divider 2 is arranged in parallel at both ends of the GIS grounding switch 3 to detect the voltage at both ends; the stroke sensor 4 is used to detect the stroke of the GIS grounding switch 3, Collect its travel signal. Among them, the impulse voltage generator 1 is essentially a DC voltage generating device, which can generate a certain set voltage value according to requirements. As other implementations, the impulse voltage generator 1 can also be replaced by other existing voltage generators. .

In this embodiment, the resistance voltage divider 2 is used to detect the voltage. The resistance voltage divider 2 is essentially a voltage sampling device. As other implementations, the resistance voltage divider 2 can also be replaced by other existing equipment such as voltage transformers. .

The output end of the mechanical characteristic tester 10 is connected to the GIS grounding switch 3 through the second electro-optical converter 9 , the second optical fiber and the second optical-electrical converter 8 , so as to realize the control of the opening and closing operation of the GIS grounding switch 3 . In order to facilitate the opening and closing operation, in this embodiment, a mechanical characteristic tester is used to perform the opening and closing operation of the grounding switch. The mechanical characteristic tester is essentially an opening and closing drive device. As other implementations, other devices capable of driving Switch opening and closing equipment. In addition, in this embodiment, the mechanical characteristic tester 10 and the GIS grounding switch 3 are connected by means of optical fiber isolation. As another embodiment, a hard wire or the like may also be used for connection.

The first input end of the processor 7 is connected to the resistor divider 2, and the second input end of the processor 7 is connected to the travel sensor 4 through the first photoelectric converter 6, the first optical fiber and the first electro-optical converter 5, and the processor 7 obtains the For the first time point corresponding to the starting change of the stroke signal and the second time point corresponding to the voltage signal jumping, the time difference between the first time point and the second time point is used as the pre-breakdown time. In this embodiment, the processor 7 and the stroke sensor 4 are isolated by an optical fiber. As other implementations, other forms of isolation or non-isolated connection may also be used.

Device Example 2:

The present invention provides a device for measuring the closing pre-breakdown time of a GIS grounding switch. On the basis of the first embodiment of the device, in order to facilitate the direct observation of the test results, the measuring device further includes an oscilloscope, and the first input end of the oscilloscope is The resistor divider 2 is connected, the second input end of the oscilloscope is connected to the stroke sensor 4, and the voltage signal and the stroke signal are displayed in the oscilloscope.

Wherein, in order to ensure the accuracy of the stroke signal, the stroke sensor 4 is connected to the oscilloscope through the third electro-optical converter, the third optical fiber and the third optical-electrical converter in sequence.

The specific embodiments to which the present invention relates are given above, but the present invention is not limited to the described embodiments. Under the idea given by the present invention, the technical means in the above-mentioned embodiments are transformed, replaced, and modified in a manner that is easy for those skilled in the art to imagine, and the functions played are basically the same as those of the corresponding technical means in the present invention. The purpose of the invention is basically the same. The technical solution formed in this way is formed by fine-tuning the above embodiment, and this technical solution still falls within the protection scope of the present invention.

Claims (9)

1. a measuring method of switch closing pre-breakdown time, is characterized in that, comprises the following steps: 1) Load the set voltage value on both ends of the grounding switch to be tested through the DC voltage generating device to control the closing of the grounding switch to be tested; 2) Obtain the travel signal before and after the grounding switch to be tested is closed, and obtain the first time point corresponding to the start of the change of the travel signal; 3) Obtain the voltage signal at both ends of the grounding switch to be tested, and obtain the second time point corresponding to the jump of the voltage signal; 4) Determine the pre-breakdown time according to the difference between the first time point and the second time point. 2 . The method for measuring switch closing pre-breakdown time according to claim 1 , wherein the DC voltage generating device is an impulse voltage generator. 3 . 3. A measuring device for switch closing pre-breakdown time, characterized in that the measuring device comprises a DC voltage generating device, a voltage sampling device, a travel sensor, a processor and an opening and closing drive device; The DC voltage generating device is used for loading a set voltage value at both ends of the grounding switch to be tested; The voltage sampling device is used to collect the voltage signal at both ends of the grounding switch to be tested; The travel sensor is used to collect the travel signal of the grounding switch to be tested; The output end of the opening and closing driving device is used to connect the grounding switch to be tested, so as to realize the closing operation of the grounding switch to be tested; The first input end of the processor is connected to the voltage sampling device, the second input end of the processor is connected to the stroke sensor, and the processor obtains the first time point and the voltage signal jump corresponding to the start of the stroke signal change. Change the corresponding second time point, and use the time difference between the first time point and the second time point as the pre-breakdown time. 4 . The device for measuring the pre-breakdown time of switch closing according to claim 3 , wherein the travel sensor is connected to the processor through the first electro-optical converter, the first optical fiber and the first electro-optical converter in sequence. 5 . of the second input. 5. The device for measuring the pre-breakdown time of switch closing according to claim 3 or 4, wherein the output end of the opening and closing driving device passes through the second electro-optical converter, the second optical fiber, the second The photoelectric converter is used to connect the grounding switch to be tested. 6 . The device for measuring the pre-breakdown time of switch closing according to claim 3 , wherein the voltage sampling device and the stroke sensor are further connected with an oscilloscope. 7 . 7 . The device for measuring the closing pre-breakdown time of the switch according to claim 3 , wherein the voltage sampling device is a resistor divider. 8 . 8 . The device for measuring the closing pre-breakdown time of a switch according to claim 3 , wherein the opening and closing driving device is a mechanical characteristic tester. 9 . 9 . The device for measuring switch closing pre-breakdown time according to claim 3 , wherein the DC voltage generating device is an impulse voltage generator. 10 .

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