Key Technology Of Optical Electrostatic Sensing System For High Voltage

The measurement method different from the traditional resistor divider and resistance and capacity divider of AC/DC high-voltage measurement, electrostatic voltmeter AC/DC high voltage measurement method in measuring process because it has a great inner impedance, which doesn’t effect on high voltage input, has an important significance in the high voltage measurement. In this paper, the high-voltage optical electrostatic voltage sensing system and its related technologies are researched and experimented.The sensing mode of electric force was studied under uniform electric field. A polyester film was used as an electrode in the uniform field, and the strain of film was measured under the balance of deflection force and electric force with the Fabry-Perot interferometer theory. The RMS voltage was measured by the strain. The mathematical model of FP electrostatic voltage sensor sensing measurement was built, using the theory of electrostatic force, Poisson theory of a circular thin plate and FP interferometer theory, through the mechanical simulation analysis of sensing unit, the structure of sensor was optimized, on the basis of FP electrostatic voltage sensor preparation, the voltage sensor sensing measurement experiment system was built, FP electrostatic voltage sensor voltage measurement experiment and research were developed in the uniform electric field, a certain range of electrostatic voltage measurement was realized. On this basis, under uniform electric field electrostatic voltage sensor was designed by using uniform strain beam, and in order to improve the electrostatic voltage sensor voltage measurement sensitivity, the feasibility of it was studied under uniform electric field.Voltage sensing mode was studied by the balance of non-uniform electric force and deflection force of the strain beam with conductor hemisphere in the uniform electric field. Uniform strain beam FBG electrostatic voltage sensor sensing measurement mathematical model was built by electrostatic mechanical and fiber optics theory analysis, the structure was optimized by distribution of electric field and mechanical simulation analysis of the sensor. Through Theoretical research and analysis, the feasibility of two FBGs to realize temperature compensation is proved. By FBG temperature sensing characteristic experiment and research, the results showed that the designed FBG temperature compensation program had better compensation effect under a certain temperature range. On this basis, uniform strain beam FBG electrostatic voltage sensing experiment system was prepared and built, using this system to carry out the voltage measurement experiment and research, experiment results showed that, the measurement range of uniform strain beam FBG electrostatic voltage sensor has more improvement than the FP electrostatic voltage sensor in the non-uniform electric field.The structure of sensor was optimized by the electric field simulation analysis of sensing unit, the structure of the vacuum optical electrostatic voltmeter was devised in the field strain area, and the corresponding external insulation structure was designed, the high-voltage optical electrostatic voltmeter that was applied in engineering was prepared, based on designed electrostatic voltmeter, to improve the voltage sensing measurement experiment and research were developed. Experiments showed that the high-voltage optical electrostatic voltmeter realizes high voltage electrostatic measurement by reasonable insulation structure design, and the range of measurement voltage and the measurement accuracy have more improvement than the sensors before.