Research Of Multi-needle Vertical Grounding Systems And Its High-frequency Applications

Grounding system is a general term for grounding electrodes buried a certain depth in the ground and the soil around them, it is divided into horizontal grounding system and vertical grounding system. As the most common means of protection, grounding system is widely used in various sectors of the national economy, it plays a vital role in the safety of equipment and human, so the research on it is of great significance.At present, with the accelerating of urbanization process and increasing shortage of land resources in China, small grounding system will become the inevitable choice in the design of power system. Meanwhile, the capacity of the power system and the use of high-frequency electronic devices are growing. Therefore, the topic of small grounding system and its high-frequency application is proposed.Firstly, on the basis of the full study in discharge theory, the design concept of new multi-needle vertical grounding electrode was proposed. Secondly, the related laws that between multi-needle vertical grounding electrode’s structure and the changes of electric field around it were studied by the finite element analysis software Maxwell-Ansoft, and then developed a new multi-needle vertical grounding electrode. Experimental results showed that the multi-needle vertical grounding electrode can effectively reduce the impulse grounding resistance, the design goals were achieved. On this basis, the construction of multi-needle vertical grounding system was completed, it marked the relations of the expected goal that grounding system miniaturization. Meanwhile, the factors that affect the grounding resistance at high-frequency were studied, and then successfully applied to the grounding system of Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Ministry of Education under the conditions of high frequency.