With the increasing penetration of wind power

abnormal voltage oscillation occurs frequently due to utilization of static var compensator(SVC)in large-scale wind power influx area

which attracts attention of researchers working on network planning and operation. An equivalent model of the system is established on the basis of reactive power and voltage control in typical large-scale wind power influx areas with software DIgSILENT/PowerFactory. Two main control modes of SVC

namely constant voltage control and constant reactive power control

are compared and analyzed via adopting different stability analysis methods including eigenvalue analysis in small signal stability

time-domain simulation and Bode plots. Moreover

the derivation method for open loop transfer function in control theory is introduced targeting certain variables. From the perspective of the new controller

the reason why oscillation occurred when it comes into use in actual wind farms is explained in theory. The results demonstrate that SVC with different control modes has different adaptability to the system's change. In terms of the number of wind farm with SVC and the impedance of the system

the constant reactive power control mode performs better than the constant voltage control mode for weak sending end systems in large-scale wind influx area.