基于位置估计的双馈风力发电机的控制策略

为了避免由机械传感器所带来的一些控制上的问题,提出了一种基于位置估计的双馈风力发电机的控制方案。在转速控制阶段,根据双馈发电机数学模型,通过采集电网电压电流,转子电压电流,采用定子磁场定向的矢量控制策略,利用转子电流矢量综合位置与定子电压矢量综合位置,对并网前后转子位置进行估算,得到转速及功率变化规律,运用这个规律可以实现对转速的控制。最后对1 MW的风力机模型进行系统仿真实验,结果表明整个转速控制区间对转子位置的估计都满足系统要求,基本上解决了风力发电机的转速和无功功率控制难的问题,验证了方案的正确性与可行性。

Control Strategy of Doubly-fed Generators Based on Position Estimation

In order to avoid some control problems on mechanical sensor,a control strategy based on the position estimation for doubly-fed generators is presented.On the stage of speed control,analyzing the mathematical model of doubly-fed generator and measuring current and voltage of the grid and rotor respectively,the rotor position is estimated by using rotor current vector position and stator voltage vector position,while the rules of variety of speed and power is applied to realize stator field-oriented vector control.finaly,the result proves that the estimated rotor position is satisfied with system demands in the whole range of speed control,and the speed and power control of the wind generator is realized.The effectiveness of this scheme is illustrated through simulation analysis and experiment on the prototype of 1 MW wind generator.