Research On The Building Model And The Control Of A Variable-speed Constant-frequency Doubly-fed Wind Induction Generator Based On PSCAD

Wind power is an important new energy and renewable energy, global wind power industry and power generation technologies are developing rapidly. China is rich in wind energy resources and has made gratifying achievements in wind power. The wind power technology has been extensively studied. Variable-speed constant-frequency (VSCF) wind power technology is the main trend in the development of world's wind power. The mature technology is still being studied home and abroad, especially the VSCF technology of MW wind turbine has much research value. This technology is still in the development stage in China, especially the frequency control technology based on IGBT needed introduction, digestion, absorption and independent innovation.In the paper it presents the current status and development trend of wind power generation at home and abroad. It shows the important of studying VSCF doubly fed induction generator system by comparison different wind generation technology. The analysis of VSCF doubly fed induction generator system mathematical model shows that the turbine's peed is allowed to change in a wide range of wind speed. It can control the frequency, amplitude and phase of excitation current (or voltage) of doubly fed induction generator rotor. Than let wind generator and wind turbine has good matching power characteristic under variable wind speed. In order to achieve the characteristics of the maximum utilization of wind power, the paper uses vector control technology such as stator voltage direction, hysteresis current modulation to track the largest wind power and the independent control of generator active and reactive power. At the same time, VSCF doubly-fed wind induction generator system can compensate reactive power to the grid. It also use simulation to verify the effectiveness of the control strategies by making a detailed analysis of the simulation results. The simulation results show that the control strategy can let VSCF doubly-fed induction generator system has good performance.