Research And Implementation Of Control System Of Parallel Operation Of Arc-Suppression Coils Based On Fuzzy Algorithm

As the scale of distribution network is increasing constantly, the capacitance current to the ground of the system increases sharply. The parallel operation of busbars in one substation and closed-loop operation of substations bring the problem of arc-suppresion coils’ parallel operation. This paper develops the control system of parallel operation of arc-suppresion coils based on fuzzy control, which can concertedly control the parallel operating arc-suppresion coils.Firstly, this paper proposes the concept of large disturbance and small disturbance of system’s capacitance current to the ground. When there happens large disturbance to capacitance current to the ground of the system, control system uses modified two-point method to calculate the current precisely. When there happens small disturbance to system’s capacitance current to the ground, control system uses fuzzy control based on GA optimization to follow the variation of the current.Then, after the calculation of system’s capacitance current to the ground, control system uses GA based on constrained optimization to allocate the compensating current, which makes the parallel operating arc-suppresion coils’ tap changing times minimum. In addition, this paper proposes monitoring technology of closed-loop operation in distribution network, which can alert when network happening unnormal closed-loop operation.Finally, this paper develops the control system of parallel operation of arc-suppresion coils which contains functions above, and the software and hardware design of the control system has been finished. As for the hardware part, auto-tuning arc-suppresion coil controller is an IPC, which includes AD board, DO board, encoder, etc. The server of control system is a powerful specia-purpose computer. As for the software part, the design of function program, display interface and webpage have been completed on the platform of Visual Studio C#.Control system has been applied to lOkV substation of Beitai steel plant in Benxi, Liao ning province. The results show that control system completely meets the design requirements, and it has great value to safe, stable and reliable operation of the grid.