A Double-Ended Protection Principle for an LCC-VSC-MTDC System with Strong Anti-Interference Ability

The DC grid technology of multi-power supply and multi-drop-point power reception is an effective solution for large-scale renewable energy integration into the grid. Line-commutated converter-Voltage source converter (LCC-VSC) grids are one more important developmental directions future that have occured in recent years. But multi-terminal high voltage direct current system has problems inconsistent boundary characteristics, control, fault response which puts higher requirements on protection scheme. Thus, a completely new principle proposed this paper. Firstly, characteristics distributed capacitance analyzed. reactive calculated by distribution parameters different frequencies different. Subsequently, analyzed, extraction algorithm proposed. polarity multi-band used to construct Finally, LCC-VSC model verifies correctness superiority scheme uses instead solve long delay problem caused capacitance. Compared with prior art, not affected stronger anti-interference ability (600 + 10 dB 1 ms).