The Calculation And Simulation Of The Powerfrequency Grounding Parameters Of Grounding Net

The grounding safety performance is a basic guarantee of the safe operation of the power system, and it include operation grounding, lightning protection ground and protection grounding. The goal of substations grounding system design is to ensure the power system when it is at fault, by cutting off power supply quickly or restricted the contact voltage and step voltage which maybe threat personal safety. In the past grounding research, people usually evaluate the security of substation grounding net by grounding resistant. In fact, the step voltage, contact voltage and the ground potential distribution which is the main factors threat to personal safety when the power system is out of order. In this paper, based on the combination of the electromagnetic field with the circuit theory and the principle of image method, and write the program for the ground potential, step voltage and contact voltage after built the mathematical model for the grounding net which is in the homogeneous soil or the vertically two-layered soil, and use the program to make a simulation about grounding net. Besides, comparing the operation results with the data which is on the reference to inspection the program whether is right or not.The program in this paper can be used to calculate the grounding coefficient of the grounding net which is in homogeneous soil or vertically two-layered soil, and also can draw the there dimensional figure of step voltage, contact voltage and ground potential, at the same time, we can observe the three dimensional figure from different angles. We can analysis the potential when the power system is out of order effective and intuitive by the there dimensional figures.Having calculated the grounding coefficient of horizontal grounding net without vertically electrode and grounding composite grounding net with vertically electrode in this paper. And having compared by the example on the reference proved the program in this paper is accurate. In order to study the influence factors of substation grounding net, by changing one parameters and keep other parameters constant to analysis the influence factors.