柔性直流引发火电机组次同步振荡的电气负阻尼关键因素分析OA北大核心CSTPCD

The negative electrical damping is the direct reason for the sub-synchronous oscillation in the near area where a large number of power electronic devices are connected to the power system.It is very important to understand the mechan-ism of electrical negative damping and to formulate suppres-sion measures that determine the key links and parameters that cause electrical negative damping.To address this problem,firstly,the complex torque coefficient transfer function was ex-panded;the extreme value of electrical damping was defined;the key oscillation modes and fractions causing negative damp-ing were determined based on mode decoupling by the electric-al damping analysis method with improved complex torque coefficients.Secondly,the electrical damping correlation factor and sensitivity were introduced to determine the key influen-cing links and parameters of electrical negative damping,and the parameter adjustment scheme was given to suppress sub-synchronous oscillation according to the sensitivity analysis results.Finally,the time domain simulation of this method is verified by the PSCAD model.