A new method for analyzing the influence of the impact load in steel plant on grid

摘要

Electric arc furnace (EAF) and other non-linear impact load are equivalent to the pollution source for power quality of grid, which will cause the device in grid to be heated and vibrated, that will increase loss, condense the life of the device and even damage it, interfere with communication, cause the relay protection to misoperate, and cause flick that will have the eyes more tired. In this paper, a new method for simulation of the impact of electric arc furnace reactive impact load on grid is presented. The voltage fluctuation at PCC (i.e. point of common coupling), caused by the reactive impact load, will be simulated by the transient short circuit, which will solve the problem that the change time of the impact load is uncertain. The proposed method will be applied to the analysis of the impact of the reactive impact load in one steel plant on grid. Comparisons of simulation and measured values of the voltage fluctuations and flicker have confirmed that the proposed method is reasonable. By analyzing the results, this paper has put forward the requirement to compensation capacity and corresponding time of the dynamic reactive power compensator device for reducing the impact of the steel plant on grid, which will make contribution for the safe and stable operation of grid and the use of the power with high quality for millions of households.