基于二极管箝位三电平变流器2MW直驱式风电系统研究

摘要

The high-voltage high-power three-level converter technology is applied in the directdriven wind power generation system with midpoint back to back diode clamped three-level structure in inverter circuit.The space vector pulse width modulation technology is used in three-level inverter; machine side converter employs the double-loop control programs with maximum torque current ratio to achieve maximum power point tracking and smooth running of the generator; grid side converter adopts the vector control of directional grid voltage to achieve active and reactive power decoupling control for constant DC voltage,and converter operates at unity power factor condition.The results show that,based on diode-clamped three-level converter,2MW direct driven wind power system not only achieves maximum wind power tracking and dynamic control of active and reactive power,but also ensures highquality power feed to the grid.%将高压大功率的三电平变流技术应用到直驱风力发电系统中,变流器电路结构为背靠背二极管中点箝位式三电平结构.三电平变流器采用空间电压矢量脉宽调制技术;机侧变流器采用基于最大转矩电流比的双闭环控制方案,实现了最大功率追踪且发电机运行平稳;网侧采用电网电压定向的矢量控制,实现了有功功率和无功功率的解耦控制,保证了直流侧电压的恒定,而且使得变流器工作在单位功率因数状态.研究结果表明,基于二极管箝位三电平变流器的2 MW直驱式风电系统,既实现了最大风能追踪和有功、无功的动态控制,又保证了向电网馈入高质量的友好型电能.