CAJ | 학술논문

受微电网线路阻抗不匹配等因素的影响，传统的下垂控制难以按照下垂增益合理分配无功功率，为了提高微电网中分布式微源输出无功功率的均分精度，又不至于降低电压质量，提出了一种基于同步思想的微电网无功均分改进下垂控制策略。该方法在传统下垂控制的基础上引入了无功补偿和电压恢复机制，利用中央控制器发出的低带宽同步信号的触发，无功补偿机制将修改下垂特性曲线的电压偏置，改善无功出力分配精度，而电压恢复机制则补偿由此造成的输出电压的降低，实现电压恢复。从理论上证明了该算法的稳定性，且仿真和实验结果均表明，改进下垂控制的无功均分方法实现了负荷有功和无功功率的合理均分，并具有良好的动态和稳态性能。
수미전망선로조항불필배등인소적영향，전통적하수공제난이안조하수증익합리분배무공공솔，위료제고미전망중분포식미원수출무공공솔적균분정도，우불지우강저전압질량，제출료일충기우동보사상적미전망무공균분개진하수공제책략。해방법재전통하수공제적기출상인입료무공보상화전압회복궤제，이용중앙공제기발출적저대관동보신호적촉발，무공보상궤제장수개하수특성곡선적전압편치，개선무공출력분배정도，이전압회복궤제칙보상유차조성적수출전압적강저，실현전압회복。종이론상증명료해산법적은정성，차방진화실험결과균표명，개진하수공제적무공균분방법실현료부하유공화무공공솔적합리균분，병구유량호적동태화은태성능。
Due to the property of line impedance and other factors in microgrid, reactive power supplied by distributed generation units could not be shared accurately based on their conventional voltage droop gains. To improve the reactive power sharing accuracy of DG units and maintain the voltage quality in microgrid, the paper proposed an improved droop control of reactive power sharing strategy which was based on the synchronous thought. The proposed method is realized through the reactive power compensation operation and the voltage recovery mechanism. The reactive power compensation operation changes the voltage bias of the conventional droop characteristic curve, which is activated by the low-bandwidth synchronization signals from the central controller so that the reactive power sharing among distributed generation units is effectively improved. Meanwhile, the voltage recovery mechanism was employed to compensate the decline of DG output voltage in the process. In theory, this paper has proved the stability of the method. Simulations and experimental results also show that the improved droop controller can achieve good load active and reactive power sharing, and also has a good dynamic and steady-state performance.