Design and Implementation of Subsynchronous Damping Controller for HVDC

Abstract

Abstract The interaction between High Voltage Direct Current (HVDC) transmission lines and turbogenerator units will cause the damage of the generator shafting and the electrical system by exchanging energy at one or more lower synchronous frequencies, resulting in the damage or even breakage of the generator shafting, seriously affecting the safe operation of the power system. To solve this problem, the Supplementary Subsynchronous Damping Controller (SSDC) is an effective method to suppress the secondary synchronous oscillation of turbogenerator units connected to rectifier side caused by HVDC. This paper combines the first standard model parameters of IEEE subsynchronous oscillation with CIGRE HVDC transmission system, and builds a HVDC transmission test system for Subsynchronous Oscillations(SSO) research in PSCAD. Based on signal test method, a narrow band SSDC is designed, and the damping in each synchronization frequency band is greatly increased. When the proportional coefficient is appropriate, the electrical damping is positive. The effectiveness of the designed SSDC is also verified by time domain simulation.