Studies On The Modeling Of Direct-Drive Permanent Magnet Wind Power Generation System And The Impact Of Grid

In recent years, affected by higher oil prices and impacts of global climate's changes, International community is increasingly given to renewable energy development and utilization; Many countries put forward a clear development objectives, formulated policies to support renewable energy development. The wind power, as most representative of the new energy, in the future will maintain rapid development. Currently variable-speed constant frequency wind power generation system includes double-fed induction generator(DFIG) and Direct-drive permanent magnet synchronous generator(D-PMSG). Compared to DFIG, D-PMSG does without gear box for reducing the mechanical loss. It has long service life, convenient maintenance and high efficiency, so it will usher in a broader development prospects. This paper researchs D-PMSG's mathematical and simulation model and problems of the transient:1. Studied the D-PMSG's mathematical model which includes wind speed, wind turbine model, mechanical transmission model, angle control model, PMSG models; Uses PSCAD/ EMTDC Power System Simulation software to establish the simulation model of the entire system.2. According to space vector pulse width modulation (SVPWM) working principle, design of the entire D-PMSG's controling system model, including:generator-side control strategy and the grid-side control strategy.3. Combination of D-PMSG's dynamic performance to analysis its transient stability in the process of grid, researches system performance based on voltage drop, earth fault, circuit fault conditions.