具有电能质量调节功能的光伏并网系统研究进展

Development of photovoltaic grid-connected system with power quality regulatory function

由于光伏并网系统出力的间歇性、不确定性等特点导致其利用率低,同时,现今电力系统对电能质量的要求越来越高,因此,有关提高光伏并网系统的利用率、改善电能质量的研究倍受关注。概述了光伏并网发电系统中电能质量调节功能的发展背景与研究意义,总结了光伏并网系统对电网电能质量的影响。以控制方法及结构的不同为依据,归纳了系统抑制谐波问题与电压质量的方法,结合仿真实例分析了不同方法的特点及适用范围,提出改善电能质量时需要统筹考虑天气环境、负载情况、实际容量、调节对象、系统类型、经济成本等各种因素。最后,指出了具有电能质量调节功能的光伏并网系统目前存在的问题,对其今后的发展方向做出了展望。

Nowadays power systems have higher demand on power quality, and the photovoltaic（PV） grid-connected system usually operates in low utilization due to the characteristics of intermittency and uncertainty, therefore, improving the utilization rate of PV grid-connected system and power quality of grid power system attracts wide attention. This paper outlines the development background and significance of power quality regulatory function in the PV grid-connected system, and summarizes the effect of PV grid-connected system on grid power quality. It concludes the methods to suppress harmonics and improve voltage profile according to different control methods and structures. The characteristics and application ranges of different methods are analyzed with examples and simulations. Then the main aspects, such as weather circumstances, load condition, real capacity, regulatory objects, system types, economic cost, etc. are proposed. Finally, the existing problems of the PV grid-connected system with power quality regulatory function are pointed out and its study direction in the future is also looked ahead.