DYNAMIC STABILITY ANALYSIS AND CONTROL METHOD FOR VOLTAGE SOURCED CONVERTER BASED HIGH VOLTAGE DIRECT CURRENT TRANSMISSION SYSTEM

A dynamic stability analysis and control method for a voltage sourced converter based high voltage direct current (VSC-HVDC) transmission system. The method includes the following steps: unlocking a converter station of the VSC-HVDC transmission system to make the VSC-HVDC transmission system run in a non-island control mode; extracting corresponding parameters of the VSC-HVDC transmission system, wherein the parameters include an effective voltage value Uof an AC system, an outgoing reactive power Qof the VSC-HVDC transmission system, a gain kof a phase-locked loop (PLL), and a proportional integral time constant kof the PLL; calculating a short-circuit ratio (SCR), an unit value of Uand an unit value of Q; calculating a key stable component; checking the sign of the key stable component to determine the stability of the VSC-HVDC transmission system.