Insulation Features Study Of Liquid Oil Medium Pulsed Power Switching

In today’s modern society, especially in the field of pulsed power, the high average-power and high repetition-rate pulsed power develop rapidly. Faced with ultra-high voltage, high current, pulsed power devices put forward higher requirements on all the elements, especially the performance of the switching elements. Switching elements in pulsed power system occupy a special position. The development of delivering stored energy to the load effectively is based on developing a variety of high-performance switches.The development and application of pulsed power technology and oil dielectric pulse power switch was introduced in this paper briefly. Then, the practical formula of liquid insulation medium, the discharge characteristics of the oil medium and the breakdown process were described. The main work of this paper contains two parts:simulation and experiment.When doing simulation, solidworks software was used to create a simple model of the pulsed power switch, Ansoft software was used to calculate the three-dimensional electric fields of the pulsed power oil medium switch in different situations. By using Ansoft software, calculation and analysis on full domain electric field distributions of liquid oil medium pulse power switch in different situations were achieved. According to the field distribution, the dissolved gases have a great impact on field intensity distribution of the oil medium. Besides, field intensity is also influenced by relative permittivity of oil. Therefore, when designing the switches, designers can take various measures, such as using liquid and solid media simultaneously, detecting oil insulation frequently, to improve the insulation level of the switch.In the experiment part, experiments were carried out in dielectric test switch and rep-rate design-verification test (DVT) switch respectively. The influences of oil flow and oil pressure on breakdown voltage were explored, as well as the corrosion behavior in different switch designs and different electrode materials, which provide a basis for the development and design of the pulsed power switches.