摘要
该文以应用于中压大功率电机驱动的三电平逆变器为对象,针对同步空间矢量调制策略,提出一种逆变器输出电流波形质量的评价方法。通过建立一个采样周期内误差电流矢量终端轨迹三角形的重心与平均误差电流矢量幅值之间的等效关系,推导得到不同开关序列作用下逆变器平均误差电流矢量幅值的表达式。在此基础上,进一步推导得到不同调制策略在一个基波周期内平均误差电流矢量幅值的表达式。以连续同步空间矢量和5种不连续同步空间矢量调制策略为例,将根据表达式计算得到的平均误差电流矢量幅值与根据傅里叶分析得到的输出电流总需求谐波畸变率进行比较,两者结果一致,验证该文提出的评价方法的正确性。所以该文提出的评价方法对于各种同步空间矢量调制策略输出波形质量的比较和开关序列的优化设计具有指导意义。
An analytical evaluation method for output waveform quality of synchronized space vector PWM strategies applied in high-power medium-voltage three-level inverters was proposed. The equivalent relationship between the mass center of the trajectory of current ripple vectors and the amplitude of the mean current ripple vector in each sample period was established. Closed-form expressions of the amplitude of the mean current ripple vector for different switching sequences were derived out. Furthermore, closed-form expressions of the amplitude of the mean current ripple vector for different modulation strategies could also be derived out. Taking continuous modulation strategy and five kinds of discontinuous modulation strategies as examples, the expressions were validated through Fourier analysis of the experimental results. Thus, the proposed evaluation method is helpful in the design of switching sequences for synchronized modulation strategies, as well as the comparison of different strategies.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2017年第21期6410-6417,共8页
Proceedings of the CSEE
基金
国家重点基础研究发展计划项目(973计划)(2013CB035600)
国家自然科学基金项目(51407127)
The National Basic Research Program of China(973 Program)(2013CB035600)
Project Supported by National Natural Science Foundation of China(51407127)
关键词
三电平逆变器
同步空间矢量调制
连续调制
不连续调制
输出电流波动
three-level inverter
synchronized space vector modulation
continuous modulation
discontinuous modulation
output current ripple
作者简介
张国政（1985），男，博士研究生，研究方向为多电平逆变器，zhanggz@tju．edu．cn；;阎彦（1981），女，博士，讲师，研究方向为电力变换器与电机驱动，yanyan@tju．edu．cn。
