Research On Potential Time Domain Spectroscopy Test System With Drive Protection

Research on dielectric mechanism of insulating medium and insulation diagnosis of power equipment have always been the research focus in the field of high voltage and insulation technology.Dielectric spectrum testing techniques such as current time domain spectrum and potential time domain spectrum are commonly used and effective test methods.However,when the potential time-domain spectroscopy is used to study the polarization of nonlinear insulation,it is found that the traditional potential time-domain spectroscopy test system has the problem that the leakage of charge along the surface of the tested sample makes the test results unable to truly reflect the dielectric response characteristics of the tested sample.In order to solve the problem of charge leakage along the surface of the sample,a three electrode structure with a high voltage driven protective electrode is proposed.Based on the three electrodes and voltage following technology,a potential time-domain spectrum test system with high voltage driving protection is designed.In order to improve the operation of the test system and reduce the cost of the test system,the test system is improved.A potential time-domain spectrum test system based on high voltage power reuse is proposed.The test system can realize the automatic control of the test system through the program-controlled relay module.In order to make the test system get more information of the tested insulation sample,a symmetrical four electrode structure is proposed according to the test method of current time domain spectrum and potential time domain spectrum.Based on the potential time domain spectrum test system of high voltage power reuse,a current measurement module is added,and a joint measurement and test system of potential and current time domain spectrum is designed.The test system can carry out measurement of polarization current and depolarization potential.For the test system proposed in this paper,the software part uses Lab VIEW to edit the program of the control part and cooperate with the hardware to realize the function of the test system.Through the research of this paper,it is found that compared with the traditional two-electrode structure,the three-electrode structure with the high-voltage drive protection electrode and the voltage following technology can effectively block the path of the charge leakage at the potential measurement electrode along the surface of the tested sample;the symmetric four-electrode structure can achieve the purpose of joint measurement of potential time-domain spectrum and current time-domain spectrum,which provide a test method for the dielectric mechanism study by polarization current/depolarization potential method.