Abstract:

Large-scale centralized new energy sending system is a unique form of power grid in China. Due to the high proportion of new energy sources and low tolerance to high-voltage direct current(HVDC) fault disturbance, there are prominent problems in the coordination between source and power network. The major potential risks, such as large voltage fluctuation, large frequency fluctuation and low frequency oscillation were analyzed. It was pointed out that the key problems of modeling include the auxiliary control of excitation system, generator protection concerned with network and generator speed control with dynamic system. The simulation evaluation process and precautions of the source network coordination in large-scale centralized new energy sending system were also proposed, which could be a reference for the actual simulation evaluation operation.

Key words: new energy, wind power uniting thermal power, generator protection concerned with network, low frequency oscillation