CAJ | 학술논문

　　为降低三相高压变频系统的总谐波畸变率，采用带辅助臂的中性点钳位型NPC逆变器。该逆变器在三电平NPC逆变器基础上，仅增加了少量的器件，可实现五电平相电压。针对该逆变器输出电平不完全独立的特点，提出一种脉冲宽度调制方法。分析了三相变频系统中Us，Eg，Er的谐波。分别在恒Us/ω、恒Eg/ω、恒Er/ω控制的情况下，采用差分进化算法对逆变器开关时刻进行优化，获得了较好的谐波优化结果。
　　위강저삼상고압변빈계통적총해파기변솔，채용대보조비적중성점겸위형NPC역변기。해역변기재삼전평NPC역변기기출상，부증가료소량적기건，가실현오전평상전압。침대해역변기수출전평불완전독립적특점，제출일충맥충관도조제방법。분석료삼상변빈계통중Us，Eg，Er적해파。분별재항Us/ω、항Eg/ω、항Er/ω공제적정황하，채용차분진화산법대역변기개관시각진행우화，획득료교호적해파우화결과。
To reduce the total harmonic distortion of three-phase high-voltage frequency-conversion system , neutral point clamped inverter with auxiliary arm is applied .This inverter can export five-level phase voltage while only small quantities of elements are added .A sort of pulse width modulation is put forward for this inverter in which output voltages are not absolutely independent .The harmonics of Us , Eg , Er in three-phase frequency-conversion system are analyzed .Differential evolution algorithm is ap-plied to switch times optimization in this inverter while Us/ω, Eg/ω, Er/ωare constant respectively .The results show that harmonics are well limited .