Kesearch On Control Strategy And Simulation Of Permanent Magnet Direct-driven Wind-power Generator System

Permanent magnet direct drive wind turbine is the mainstream mode as a variable speed constant frequency wind power system currently, the generation control technology has become an important wind power technology research. This dissertation throughtfully studies the control system of the Permanent Magnet Synchronous Generator (PMSG). It focuses on the control strategies of Grid Side Converter (GSC) and Machine Side Converter(MSC), the main work is as follows:(1) Through the rational design of filter and control parameters, it ensures the Total Harmonic Distortion(THD) of output current in power to meet grid-connectted requirements, and further to achieve Maximum Power Point Tracking(MPPT) control, constant power tracking control, and no-load cutting-in control, and built PMSG model in RTDS simulation platform.(2) Parameters of the PI controller is designed according to the perspective of the whole system stability, which could coordinate the control strategies of machine side converter and grid side converter in the wind power generation.(3) For the Low Voltage Ride Though(LVRT) ability of PMSG sysytem, using improved control strategy and increasing hardware circuit (crowbar) method respectively to realize the ride through in the symmetric dip case, using deadbeat control strategy in the asymmetric dip case.The models are simulated in RTDS and PSCAD, and the results illustrate that the methods presented in this paper are effective and provide reliable reference to practical engineering.