Nonlinear Behavior Analysis And Control Of Subsynchronous Oscillation In Power System

With the development of our country electric power industry, High-voltage direct current transmission(HVDC) technology and Series capacitor compensation technology get the long-term progress on the realization of the large capacity power transmission over a long distance. The application of series capacitor compensation and power electronic technology may lead to subsynchronous oscillation problem of power system has been widely concerned. Further study of the mechanism of subsynchronous oscillation and how to effectively suppress subsynchronous oscillation is of great significance.This paper first introduced the subsynchronous oscillation of the research background and research methods, respectively expounds cause subsynchronous oscillation of four basic types and mechanism. Base on the first standard IEEE subsynchronous oscillation model, make a analysis in time domain simulation, meanwhile, use complex torque coefficient method, by comparing the damping characteristics of mechanical system and electrical system, determine the subsynchronous oscillation in the high-voltage direct current transmission system stability.Use HVDC converter voltage, electric current switching function for the tool,analytically deduced the HVDC rectifier ac/dc side of the transmission relationship between the time synchronization between electric parameters. When the system subsynchronous oscillation occurs, including steam turbine shaft system of the whole power system status, the amount of time synchronization component in the system of transmission and transformation between each link between relations.On this basis, this paper based on the single channel damping scheme designed a kind of more convenient, easy to project implementation supplementary subsynchronous damping controller(SSDC). The controller object for system specific oscillation mode,through the determination of oscillation energy maximum oscillation frequency, designed parameters of each part. Based on CIGRE high-voltage direct current transmission model,validated in PSCAD simulation software. Simulation results demonstrate, the SSDC design can effectively suppress subsynchronous oscillation...