Modeling And Simulation Of Variable-speed Constant-frequency Doubly-fed Induction Wind Turbine Generator Based On Pscad

The fossil energy is limited and the problems such as short of power and environmental deterioration are evident, nowadays. It is important for fixing up those problems to make use of the renewable energy, such as wind energy. At present, all kinds of the technologies of wind turbine are in the ascendant and the models of the wind turbine are different. The double fed AC excited generator of Variable speed and Constant frequency (VSCF) has lots of excellent characteristics, hence, the paper will study on the foundation of the simulation model about the doubly-fed AC excited generator and related controllable theories.The main contact of this paper will be illustrated with four aspects.Firstly, this paper will introduce the composing of the wind turbine, describe the mathematics model of the wind turbine and build the simulation model of pitch control system. This paper will also give the method how to optimize the power of the double fed generator of VSCF and enhance the using rate of wind energy. The pitch control system is a part of the wind power system which can make the VSCF realized.Secondly, this paper will study on the mathematics model of the wind turbine of VSCF using the basic theories of the machine, including the wind model and the double fed generator model. In addition, the structure, operation principle and the control strategy of double PWM transducer will be described in this paper.Thirdly, this paper will build the simulation models of wind speed, wind turbine and double fed wind turbine of VSCF based on the mathematics model by a excellent power simulation software- pscad/emtdc. The technology of stator magnetic oriented control will be taken to realize the individual regulation of active power and reactive power and to meet the demand of the power system for reactive power. And make the control of electric machine simply to up to the effect of the control on the DC machine. The simulation results indicate that the control strategy is right.Finally, following the power from the double fed generator of VSCF is injected into network, when the broken of network come out, this paper mainly focus on the situation proved by simulation that the double fed generator of VSCF can transmit the reaction power to the network and compensate the network voltage ,when the network voltage drop.