基于SVPWM三电平变换器的变速恒频风力发电系统

摘要

分析了基于空间电压矢量脉宽调制(SVPWM)的三电平变换器,提出将其引入变速恒频双馈风力发电系统.整体分析了基于三电平的变速恒频双馈风力发电系统模型,并分别详细分析了基于三电平SVPWM网侧变换器的数学模型和控制结构,机侧空载并网的数学建模和控制结构.仿真结果表明,该三电平变换器有效降低了开关损耗;减小了纹波电流;输出电平增多,减小了电压变化；波形质量得到了很好的改善.仿真结果还表明,该三电平变换器能有效地实现风力发电系统的变速恒频控制,适用于变速恒频双馈风力发电系统.%Three-level converter based on space voltage vector pulse width modulation (SVPWM) was analyzed, which was introduced to the VSCF doubly fed wind power generation system. The grid side converter mathematical models and control structures based on three-level SVPWM were analyzed. The machine' side converter mathematical models and control structures of no-load grid-connection based on three-level SVPWM were analyzed. The simulation results show that, the three-level converter effectively reduces the switching losses and the ripple current. The output level is increased, the diversifications of voltage are reduced, and the waveform quality is very well improved. The simulation results also show that, the three-level converter can effectively achieve VSCF wind power system control. The three-level converter can be applied to VSCF doubly fed wind power generation system.