变风速下永磁直驱风电机组频率—转速协调控制策略

Coordinated Control of Frequency and Rotational Speed for Direct Drive Permanent Magnet Synchronous Generator Wind Turbine at Variable Wind Speeds

在分析永磁直驱风电机组变速运行特性的基础上,在电力系统电磁暂态分析软件平台上建立了永磁直驱风电机组的动态模型,提出了一种新的永磁直驱风电机组频率—转速协调控制策略。该控制策略能够有效减少风电机组的转矩突变,在风电机组参与频率调整时对转速进行调节,并且能够有效增大系统惯性。将所提出的频率—转速协调控制策略与单一的频率控制策略进行仿真对比,结果表明,采用频率—转速协调控制策略的永磁直驱风电机组能够有效增大系统惯性,减小频率波动幅度和转矩突变。

A dynamic model of direct drive permanent magnet synchronous generator（D-PMSG） wind turbine is developed with ElectroMagnetic Transient Program/Alternative Transient Program（EMTP/ATP） software,on the basis of operational characteristics of D-PMSG with variable speeds.A novel coordinated control strategy of frequency and rotational speed is proposed to prevent second frequency variation caused by activation of rotational speed protection.Simulation results show that the proposed control strategy can capture maximum wind power in normal operation,and also minimize frequency variation following a sudden change of large load,which avoids second frequency variation and torque sudden change.