| In order to calibrate the high voltage test equipment, we need to design a standard impulse voltage divider. The response characteristic of the standard impulse voltage divider is an important index when manufacturing the divider. During the designing process of the divider, the grading ring and the high voltage arm play the very important role in measuring the steep pulse with a very quick rising time. Therefore, it is meaningful to improve the divider performance for assurance of the accuracy when measuring the steep impulse.This graduation project developed a resistance voltage divider, which is used as a standard impulse voltage divider. The rated voltage is 300 k V. During the designing process, we design the high voltage arm, low voltage arm and the secondary attenuator in succession. Meanwhile we give the design basis. The selection of the resistance wire of the high voltage arm is karma wire with good temperature coefficient and linearity. The resistance wire is wound on the rectangular insulation skeleton using the non-inductance winding method. Thus the residual inductance is reduced. The discharge temperature is calculated and the temperature coefficient of the high voltage arm is measured. For the purpose of ensuring that the aureole and the flashover phenomena will not happen and optimizing the square wave response time and the overshoot of the resistance voltage divider, the software Elecnet, developed by company Infolytica, was selected to calculate the electric field of the resistance voltage divider and achieve the stray parameters. During the calculation, the grid of the air bag is divided efficiently. We also used the ATP software to establish the equivalent model for circuit simulation, to calculate the square wave response time. The result shows that the resistance voltage divider should has a shield electrode at its top position. The shape of the shield electrode should be a double ring cone shape. In addition, the project tested the low-voltage square wave response. Through the analysis of the response time and the overshoot, we explain the influence on the response waveform of the damping resistance, the high-voltage lead length and the connection method. So a standard measurement system could be established for the prototype. Through debugging the measurement system, we reduce the interference signal efficiently and make the measurement result more accurate. The response time of the designed standard impulse voltage divider is 4.37 ns. The dynamic response performance is better than the literature we search. |
