Measuring device for online monitoring of surface potential

Abstract

The invention provides a measuring device for online monitoring of surface potential. The measuring device comprises: a signal excitation portion and a sample to be tested, which are arranged in a test chamber with constant temperature and constant humidity, and a signal collection portion arranged at the outside of a vacuum chamber; the signal excitation portion comprises: a ground electrode, a pin electrode and a high voltage source, wherein: the ground electrode is arranged on an upper surface of the sample to be tested and is in close contact with the sample to be tested, the pin electrodeis arranged on a lower surface of the sample to be tested through a first insulating bracket, and the high voltage source outputs a DC high voltage; and the signal collection portion comprises: a three-dimensional mobile platform, a first collection card, a probe, an electrostatic voltmeter, a second collection card and a detection module. The invention relates to online measurement of dielectricsurface potential, by means of the three-dimensional online measurement of the surface potential in a controllable environment, a high voltage can be applied to the pin electrode, synchronous measurement of the probe can be achieved, the defects of the offline measurement of the traditional electrostatic probe method are compensated, and a support is provided for the test and evaluation of dielectrical properties of dielectric in the future.

Description

technical field [0001] The invention relates to a technique in the field of potential measurement, in particular to a measuring device for online monitoring of surface potential. Background technique [0002] For high-voltage DC electrical insulation equipment, the accumulation and dissipation of the surface charge of the insulator in the equipment is a hot topic in the research of high-voltage DC gas-insulated equipment. Under the action of DC high voltage, the charge accumulation on the surface of the insulator is determined by the electrical properties of the solid and gas itself and the electric field conditions. At present, the main measurement methods for the surface potential of insulators are photoelectric measurement method and electrostatic probe method. The photoelectric measurement method is an online measurement method. The surface potential is retrieved through the light intensity collected by the CCD. The operation is complicated and greatly affected by visibl...

AI Technical Summary

Problems solved by technology

At present, the main measurement methods for the surface potential of insulators are photoelectric measurement method and electrostatic probe method. The photoelectric measurement method is an online measurement method. The surface potential is retrieved through the light intensity collected by the CCD. The operation is complicated and greatly affected by visible light. Potential distribution can only be obtained by noise reduction processing, and there is no uniform reference

Due to the high measurement accuracy of the electrostatic probe method, the existing measurement devices mostly use an electrostatic voltmeter with an oscillating Calvin probe for measurement, but the defect of this technology is that there will be spatial interference between the application of the needle tip voltage and the measurement of the electrostatic voltmeter probe As a result, online measurement cannot be realized, and only the surface potential attenuation measurement after applying voltage can be realized. It is an offline measurement scheme

[0003] The surface charge dissipates quickly when the external voltage is removed. In the original off-line measurement process, the conversion between the electrostatic voltmeter probe and the high-voltage electrode takes a certain time, and the surface potential change at the moment when the external voltage is removed cannot be captured in time. The potential change is precisely the moment when the surface charge dissipates most rapidly, but there is no online measurement method based on an electrostatic probe in the prior art

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