【摘要】 新型的Z源拓扑结构因其独特优点引起国内外的关注,但是在轻载条件下存在直流母线上电压波动较大的缺点.针对Z源逆变拓扑结构的特点,详细地分析了引起直流母线电压波动的原因,根据逆变前后的功率不变原理,通过引入2个功率平波电路使产生的功率的幅值和频率波动功率相等,方向相反,从而达到减小了直流母线电压的波动和改善直流母线电压质量的效果,并且消除了直流母线上的电压畸变.应用Matlab/Simulink进行了仿真,仿真结果表明加入平波电路之后,不仅消除了直流母线上的电压波动和电压畸变,而且获得了满意的交流输出电压波形,验证了理论分析的正确性.更多还原

【Abstract】 As a kind of novel Topology,Z-source is concerned more and more widely at home and abroad because of its unique advantages.However under light load conditions,the main disadvantages of Z-source is worse voltage ripple on DC link.According to the characteristics of Z-source inverter,this paper analyzes in detail the reasons that cause voltage ripple on DC link.By the Constant Power rule,two smoothing-power circuits with the same magnitude and frequency power,but in opposite directions are employed to improve the quality of DC link voltage and eliminate the voltage distortion,additionally.Matlab simulation results verify that smoothing-power circuits can not only reduce voltage ripple and eliminate voltage distortion on DC link voltage,but also obtain satisfactory AC voltage output,which validate the correctness of the theoretical analysis.更多还原