摘要
并网导则要求并网逆变器故障穿越过程中向电网注入功率帮助电网电压恢复。然而实际电网存在低次谐波,注入电网的有功和无功功率通过线路阻抗将影响公共耦合点电压质量,降低并网系统运行可靠性。针对此问题,分析电网电压谐波分量对公共耦合点电压的影响,然后提出一种公共耦合点电压恢复控制策略,通过调节正序负序和谐波控制系数改善公共耦合点电压质量。最后对传统方案和提出的方案进行实验研究,实验结果验证了提出方法的有效性。
The grid code requires that the grid-connected inverter inject powers to achieve the voltage recovery during grid faults. However, due to the grid harmonics, the power injection through the line impedance may affect the power quality at the point of common coupling and reduce the system reliability. In order to solve the problem, the relationship between grid harmonics and PCC voltage was analyzed. Then a new voltage recovery control strategy is proposed. It adjusts the control coefficients of positive/negative sequence and harmonics to improve the voltage quality. Finally, the experimental tests of the conventional and proposed control solutions were carried out. The experimental results verified the effectiveness of the proposed method.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2017年第17期5118-5124,共7页
Proceedings of the CSEE
基金
国家自然科学基金项目(51677161)
河北省杰出青年基金项目(E2016203133)~~
关键词
谐波不平衡电网电压
故障穿越
并网逆变器
故障恢复
harmonic and unbalanced grid voltage
fault ride through
grid-connected inverter
fault recovery
