Research On The Entire Set Property Of VSWT And Software Integration

This article develops the entire set model of variable speed wind turbine (VSWT), based on the theory of aerodynamic calculation for the horizontal axis wind turbine (HAWT) and dynamic analysis of the drive train. To various types of operating control schemes, the steadily and dynamic processes of HAWT are systematically analyzed and their more accurate prediction models are developed. This article is one of the kernel problems to be resolved in the national "863 Plan" project "Full System Loads Analysis and Optimization Design of Wind Turbine Software". Based on these, with tool of Visual C++ the program which realizes the numerical algorism is integrated with the CAD software "Blade Design for windows". This article includes three sections: the entire set model of VSWT, the basic control rules of the generator, software development of the system.The entire set model of VSWT figures out the aerodynamic problem of wind turbine when it's rotate speed and pitch angle are kept changing. The aerodynamic calculation module develops the transformation of the reference frame between the blade coordinate and the tower coordinate. Considering many other error when operating, the model can predict the aerodynamic characteristics of the rotor more accurately. The closed control system of the VSWT involves the wind turbine, generator and drive train model. Considering the rigidity and damper of the axle, the flexible shaft model makes the analysis of the intensity and the stability more accurate.Based on the entire set model of VSWT, this article introduces some control rules to achieve the superiority of the VSWT: below rated, tracing the optimal power; above rated, restricting the rotate speed or power to their limit to obtain steady and safety output. Different control rules are used in different operation area. The indirect speed control (ISC) method is used when the wind speed is below rated. The ISC predigest the closed loop control system, because the measure wind speed is not necessary. And then the article establishes the steadily operating parameter of the VSWT, and introduces the design of the rotate speed/power PI controller in detail. The theory develop in this article can be an effective one on the design of the VSWT.