| 摘要: |
| 目的 传统的同相层叠( Phase Disposition, PD) 调制法在应用于级联 H 桥逆变器时的谐波性能较好,但存在
各单元之间的输出功率不均衡问题,为解决功率不均衡问题的同时保留较好的谐波性能,提出一种改进优化的调
制策略,简化了控制难度的同时,使逆变器功率均衡,输出较好的电能质量。 方法 先对调制波优化,简化控制;然后
对各单元的开关信号进行逻辑运算,重新分配开关信号,使各单元的开关导通时间相等。 结果 对改进优化后的调
制与传统 PD 调制仿真,证明改进优化后的调制不会改变传统 PD 调制的输出电压特性,可以实现各单元的功率均
衡;最后对改进优化的调制进行实验验证。 结论 改进优化后的调制简化了控制,保证了功率均衡,得到了较好的输
出电压。 |
| 关键词: 级联 H 桥 调制策略 逻辑运算 功率均衡 |
| DOI： |
| 分类号: |
| 基金项目: |
|
| Power Balance Modulation Strategy for a Novel Seven-level Inverter |
|
GUO Meng
|
|
School of Electrical and Information Engineering Anhui University of Science & Technology Anhui Huainan 232001
China
|
| Abstract: |
| Objective The traditional phase disposition PD modulation method has good harmonic performance when
applied to cascaded H-bridge inverters but there is an imbalance in output power between different units. To solve the
problem of power imbalance while preserving better harmonic performance an improved and optimized modulation strategy
was proposed to simplify the control difficulty and at the same time make the inverter power balanced and output a better
power quality. Methods Firstly the modulating waveform was optimized to simplify the control. Then the switching
signals of each unit were logically operated and the switching signals were redistributed so that the switch conduction time
of each unit was equal. Results Simulation of improved and optimized modulation and traditional PD modulation proved
that the improved and optimized modulation will not change the output voltage characteristics of traditional PD modulation
and the power balance of each unit can be realized. Finally experimental verification was conducted on the improved and
optimized modulation. Conclusion The improved and optimized modulation simplifies the control ensures power balance
and yields a better output voltage. |
| Key words: cascaded H-bridge modulation strategy logic operation power balance |
