In order to improve the performance of vertical axis wind turbine, the variable pitch vertical axis wind turbine (VAWT) was studied. The optimum pitch angles at different azimuth angles were calculated by the blade element theory to maximize the drive moment of blade at any position. After doing dynamic regional UDF ( user-defined function) approach on sliding mesh, dynamic mesh and a combination of both, the diverse numerical simulation methods of active control for variable pitch vertical axis wind turbine were built. Finally, the total torque generated as well as the power coefficient were obtained. The reliability of numerical simulation was verified by comparative analysis between the experimental and simulation results about VAWT, The results indicated that the power coefficient of vertical axis wind turbine was improved by the method of variable pitch, especially in the case of low tip speed ratios (TSR) , where the capability of self-starting was improved greatly. Compared with the fixed-pitch vertical axis wind turbine, the power was increased by about 90% at the tip speed ratio of 1. 5 , 2. 0 and 2. 5.%为了提高垂直轴风力机的性能,针对变桨距垂直轴风力机,利用叶素理论求得叶片在不同方位桨距角的变化规律,使叶片在各个不同位置升力系数达到最大；通过滑移网格、动网格、滑移网格动网格组合等动区域方法的研究,实现了变桨距垂直轴风力机主动控制数值模拟方法的多元化；最终获得不同叶片各自产生的总力矩和风能利用率.用垂直轴风力机的试验和模拟对比分析,验证了数值模拟结果的可靠性.结果表明,采用变桨控制规律的垂直轴风力机,提高了风力机的风能利用率,尤其是在低尖速比情况下,很大程度上改善了风力机的起动性能,尖速比为1.5、2.0、2.5时,相对定桨距风力机功率都增大90％左右.
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