具有限定功率运行的永磁直驱风力发电并网控制设计

摘要

当风力发电或光伏电站这些间歇式可再生能源因外界环境影响而出力过高时，会使得配网系统潮流发生变化，并网处电压会超出运行的安全限值范围。为使系统处于可控范围，可对这些能源进行实时容量限制。对直驱式永磁同步风力发电系统的控制策略进行了研究，分析了风机输出功率曲线，设计了最大风能跟踪和限定功率运行输出的控制方法和系统后级逆变并网控制方法，使得风力发电系统具有最大功率跟踪或限定功率运行、并网有功/无功功率独立控制等功能。最后建立了风力发电并网系统仿真模型，仿真结果对所设计控制策略进行了验证。%When the intermittent renewable energies, such as wind generation or PV plant, generate more powers under the condition of the environmental influence, the tidal current of the distribution network will change and the voltage at the connected-grid point may exceed the safe limited range. In order to avoid the above phenomenon, it could be done to limit the output energy for these power generation systems. The control methods for the directly-driven permanent magnet (PM) wind generation system are studied, output power curves of the wind turbine are analyzed, control methods of the optimal wind-energy tracking or limiting power operation and end-stage control strategy of the system are designed. This makes wind generation system and PV generation system have the functions of MPPT or limiting power operation, and independent control of grid-connected active power and reactive power. At last, the simulation model of wind generation system is built, and the control strategy is verified by the simulation results.