弱电网条件下基于阻抗的稳定性判据重塑

发布时间：2018-01-04 20:00

本文关键词：弱电网条件下基于阻抗的稳定性判据重塑　出处：《电网技术》2017年09期 　论文类型：期刊论文

【摘要】：弱电网条件下电网阻抗所具有的不确定性以及宽范围变化特性会严重影响逆变器并网系统的控制性能,甚至可能导致系统不稳定。当前利用电网阻抗与逆变器等效输出阻抗的比值来判定系统是否稳定的阻抗分析法,虽然在一定条件下可以判定逆变器并网系统的稳定性,但存在表征系统稳定性裕度不准确,以及当逆变器控制参数发生变化时可能导致的传统基于阻抗的稳定性判据不再适用的问题。针对上述传统阻抗分析法存在的不足,对传统基于阻抗的稳定性判据进行了重塑,重塑后基于阻抗的稳定性判据不仅能够精确表征系统的稳定性裕度,而且对变参数控制并网逆变器也具有普适性,保持了阻抗分析法的优良特性。最后,在弱电网条件下,以三相LCL型滤波的并网逆变器模型为基础,通过仿真分析验证了文中理论分析的正确性与重塑方案的可行性。
[Abstract]:Under the condition of weak grid, the uncertainty of impedance and the characteristics of wide range variation will seriously affect the control performance of grid-connected inverter system. At present, the ratio of power grid impedance to inverter equivalent output impedance is used to determine whether the system is stable or not. Although the stability of grid-connected inverter system can be judged under certain conditions, the stability margin of the system is not accurate. And when the inverter control parameters may cause the traditional impedance based stability criterion is no longer applicable. In view of the shortcomings of the traditional impedance analysis. The traditional stability criterion based on impedance is remolded. The stability criterion based on impedance after remodeling can not only accurately characterize the stability margin of the system, but also have universality for grid-connected inverter controlled by variable parameters. The excellent characteristics of impedance analysis method are maintained. Finally, under the condition of weak grid, the grid-connected inverter model of three-phase LCL filter is used as the foundation. The correctness of the theoretical analysis and the feasibility of the remolding scheme are verified by simulation analysis.
【作者单位】：上海电力学院电气工程学院;
【基金】：国家自然科学基金面上项目(51777120)~~
【分类号】：TM464;TM712
【正文快照】： 真分析验证了文中理论分析的正确性与重塑方案的可行性。0引言随着能源危机和环境污染的日益加剧,利用可再生能源发电的分布式发电技术得到了快速发展,其在电网中所占容量也持续增大[1]。由于分布式发电系统多接于电网末端,大部分输电线路较长,线路电抗较大,且存在多级变压环

【相似文献】