摘要
为了降低大功率有源逆变系统中器件的等效开关频率,减少开关损耗,同时抑制直流侧电压波动时逆变器输出电压包含的寄生谐波,采用基于特定谐波消去法(SHEPWM)的非对称脉宽调制策略(optimal partly unsym-metrical switching angle,OPUS)和改进开关函数法,实现了逆变器的低频化和抑制寄生谐波。研究结果表明,在直流侧电压产生幅值为直流电压15%的2倍频波动时,改进的OPUS控制策略消除了输出线电压中的3、7次非受控谐波,并使得受控的基波和5次谐波电压的幅值和相位达到设定值。该仿真结果证明了结合改进开关函数法的OPUS能够应用在大功率有源逆变系统中,并且能够改善逆变器在直流侧电压小幅波动情况下的输出电压性能。
In order to decrease switch frequency and eliminate parasitic output harmonic voltage,an optimal partly unsymmetrical switching angle(OPUS) method,which was based on selective harmonic elimination pulse-width modulation(SHEPWM) and improved switch function,was offered for active inverter with DC-link ripple.The research results indicate that new OPUS can eliminate the unwanted 3rd and 7th output harmonic voltages but maintain the fundamental and 5th output voltages to the set values even though there is 15% 2nd harmonic on the dc bus voltage.Simulation results further confirm that the validity of the proposed switching strategy can be used in high power active inverter system,and can improve the VSC output voltage during dc bus ripple.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2012年第2期483-489,共7页
High Voltage Engineering
基金
国家自然科学基金(50977068)~~
关键词
半周期对称
脉冲宽度调制
电压源换流器
二倍频波动
特定谐波消除
改进开关函数
half-wave symmetry
pulse width modulation
voltage-source converter(VSC)
double line-frequency ripples
selective harmonic elimination
improved switching function modulation