Accurate active power-sharing in low-voltage islanded microgrids using a distributed secondary cooperative control

This paper presents an accurate active power-sharing in low-voltage (LV) islanded microgrids by synthesizing voltage-real power droop and frequency-reactive power boost (PVD/QFB) method and distributed secondary cooperative control. In contrast to conventional droop method, which may lead to poor stability in LV microgrids, PVD/QFB method brings the stable condition to islanded LV microgrids. The utilized distributed secondary cooperative control removes the substantial active power-sharing error of PVD/QFB method. Therefore, the capability of PVD/QFB method in LV microgrids is improved and, moreover, it becomes practical for both parallel inverters and networked microgrids. The microgrid voltage restoration is also provided by aforementioned secondary control. Finally, a simulation is conducted in PLECS software to verify the presented method.