针对网状结构交流微电网中无功功率无法均分而产生系统环流的问题,提出基于时序分阶段控制的改进下垂控制策略。首先通过分阶段时序信号控制的迭代方法,消除线路阻抗不匹配对无功分配精度的不利影响。其次,当DG单元输出电压降至限定最小值时,中央控制器发送时序信号使各DG切换至电压恢复阶段,以同步恢复电压至参考值。为维持电压恢复过程中无功均分的独立性,以等容量的微电源为例对微电网进行稳定性分析。最后,通过Matlab/Simulink仿真和RT-LAB实验,验证所提策略的正确性。
Abstract
Aiming at the problem that the reactive power in the AC microgrid with mesh structure cannot be divided equally and the system circulating current is generated, an improved droop control strategy based on sequential phased control is proposed. First, the iterative method of phased sequential signal control is used to eliminate the adverse effect of line impedance mismatch on the accuracy of reactive power distribution. Secondly, when the output voltage of the DG unit drops to a limited minimum value, the central controller sends a timing signal to make each DG switch to the voltage recovery stage, and synchronously recover the voltage to the reference value. In order to maintain the independence of the equal distribution of reactive power during the voltage recovery process, the stability analysis of the microgrid is implemented with a micro power supply of equal capacity as an example. Finally, through Matlab/Simulink simulation and RT-LAB experiments, the correctness of the proposed strategy is verified.
关键词
微电网 /
网状结构 /
功率均分 /
下垂控制 /
时序信号
Key words
microgrid /
mesh networking /
power sharing /
droop control /
timing signal
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基金
国家自然科学基金（61873159）; 上海市科学技术计划委员会（18020500700）; “电气工程”上海市二类高原学科和上海市绿色能源并网技术研究中心（13DZ2251900）
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