摘要
采用最大转换效率来衡量光伏并网逆变器的发电效率的评价方式存在一定的局限性。文章通过分析空间矢量脉宽调制(SVPWM)和不连续脉宽调制(DPWM)方式下光伏并网逆变器损耗分布情况,比较了两种调制方式以及开关频率对逆变器全功率范围内加权效率的影响,提出了一种在轻载工况下采用SVPWM、重载工况下采用DPWM、在低直流电压等级下提高功率器件开关频率的分段调制策略,并在500 k W光伏并网逆变器上进行了加权效率试验。试验结果验证了该分段调制策略的有效性。
There are limitations in the evaluation strategy on power generation efficiency of PV grid-connected inverter with maximum conversion efficiency. Loss distribution of grid-connected PV inverter were analyzed with SVPWM (space vector pulse width modulation) and DPWM (discontinuous pulse width modulation) schemes, and impacts of the two modulation schemes and switch frequency on the full-scale weighting efficiency were compared. A segmental modulation method was proposed which used SVPWM strategy under light load condition, DPWM strategy under overloading condition and improving switching frequency of power device under low DC voltage condition. Weighting efficiency of a 500 kW PV grid-connected inverter was proceeded and the experiment results showed the validation of this modulation strategy.
出处
《大功率变流技术》
2016年第6期31-36,共6页
HIGH POWER CONVERTER TECHNOLOGY
基金
国家高科技研究发展计划(863计划)(2015AA050604)
关键词
SVPWM
DPWM
开关频率
加权效率
分段调制
开关器件
滤波电感
SVPWM
DPWM
switching frequency
weighting efficiency
segmental modulation
switch device
filtering inductor