摘要
三相AC/DC变流器广泛应用于中高功率场合,空间矢量脉宽调制(space vector pulse width modulation,SVPWM)以其直流电压利用率高、谐波含量低等优势,成为三相AC/DC变流器的一种常用控制方式。其需要检测电网电压进行锁相,得出电网电压的瞬时相位角,并参与坐标变换,最终得到空间电压矢量的基准。然而,由于电网电压存在畸变,且对电网电压的检测和锁相角计算过程中会产生一定的误差,从而影响控制精度。针对可实现能量双向流动的三相AC/DC变流器,讨论进行无锁相控制的可行性,提出一种无锁相环SVPWM控制方法,分析电网实际频率与参与坐标变换的相位角给定频率出现偏差时对变流器的影响,并采用无功功率闭环调节控制策略,对频率给定进行实时校正,最后通过仿真和实验验证了理论分析的正确性。
Three-phase AC/DC converters are widely used in medium and high power applications. SVPWM is the most common control method for the advantage of high DC voltage utilization and low harmonic content. The method needs to detect the grid voltage with the phase locked loop. The instantaneous phase angle of the grid voltage can be calculated for the coordinate transformation. Thus the reference space voltage vector can be obtained. However, the grid voltage distortion may exist. Moreover, the detection of grid voltages and the calculation of phase angles may have errors, which would influence the control precision. This paper discussed the feasibility of the SVPWM control method without the phase-locked loop （PLL） for bidirectional three-phase AC/DC converters, proposed a control method without PLL, analyzed the effect of frequency deviation, and showed the method of frequency correction using reactive power closed-loop regulation. Finally, simulation and experimental results verify the theoretical analysis.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2013年第36期79-87,12,共9页
Proceedings of the CSEE
基金
国家自然基金项目(51377082)
省产学研联合创新资金--前瞻性联合研究项目(BY2012021)
江苏省优势学科建设项目普通高校研究生科研创新计划资助项目(CXZZ12_0151)~~
关键词
三相SVPWM
双向运行
无锁相环
坐标变换
频率校正
three-phase space vector pulse widthmodulation （SVPWM）
bidirectional operation
no phase-locked 10019 （PLL）
coordinate transformation
frequencycorrection
