摘要
风电并网系统中Z源网络的电容电压纹波影响电容参数的选择,增大了系统体积和成本。传统的脉宽调制策略是将一个开关周期的直通时间平均分为6份,分别插入不同的状态矢量之间。该文提出一种抑制Z源网络电容电压纹波的改进脉宽调制策略,通过分析有效状态矢量和直通零矢量下Z源网络电容电压的升降,可在一个开关周期内直通时间总和不变的前提下,改变不同状态矢量之间的直通零矢量时间,有效减小Z源网络电容电压的最大峰值。仿真与实验结果表明,与传统调制策略相比,所提方法减小了风电并网系统中Z源网络的电容电压纹波,从而在相同系统参数下降低了所需电容量。
In traditional pulse width modulation(PWM) strategy for Z-source inverter, the shoot-through time interval is divided into six equal parts. In this manner, the capacitor voltage ripple is not optimized. This causes to use relatively large capacitors in the Z-source grid-connected wind generation system. In this paper, an improved PWM strategy was proposed. The shoot-through time were rearranged according to the active state and zero state to achieve the optimized voltage ripple across the Z-source capacitor. The operational principle of the improved PWM strategy was analyzed in detail, and the comparison of voltage ripple under existing and improved PWM strategy were given. Simulation and experimental results on the Z-source grid-connected wind generation system are given to verify the analysis.
出处
《电工技术学报》
EI
CSCD
北大核心
2015年第S2期135-142,共8页
Transactions of China Electrotechnical Society
基金
国家自然科学基金资助项目(51377050)
关键词
风力发电
Z源逆变器
直通零矢量
纹波抑制
脉宽调制
Wind power generation
Z-source inverter
shoot-through
ripple suppression
pulse width modulation
