Stabilization of DC MicroGrid Systems Using the Loop-Cancellation Technique
Jakkrit Pakdeeto, Kongpan Areerak, Serhiy Bozhko, Kongpol Areerak
Abstract
DC microgrid systems (DCMGs) feed power to constant power loads (CPLs) via transmission lines. Although these systems are commonly used worldwide, CPLs have negative impedance effects. These loads can significantly degrade the system stability. Therefore, stability study is very important to avoid inefficient operations. The model proposed in this article can be derived using a combination of the direct quadrature (DQ) method and the generalized state-space averaging (GSSA) method. This model is suitable for analyzing the system stability using the eigenvalue theorem. For stability analysis, the proposed (DCMGs) will be unstable before reaching the rated power when the irradiance is equal to 0 W/m <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . Consequently, the loop-cancellation technique is applied to mitigate the unstable operation until the operation at the rated power can be achieved. Experimental and simulation results were used to confirm the theoretical analysis. The system performed well, and the results proved that the system could be stabilized using the proposed technique.