Constant Power Load Stabilization in DC Microgrids Using Continuous-Time Model Predictive Control

• Published in: Electronics (Basel) Vol. 11; no. 9; p. 1481
• Main Authors: Alidrissi, Youssef, Ouladsine, Radouane, Elmouatamid, Abdellatif, Errouissi, Rachid, Bakhouya, Mohamed
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 05.05.2022; MDPI
• Subjects: Algorithms; Continuous time systems; Converters; Distributed generation; Disturbance observers; Engineering Sciences; Power; Predictive control; Stability; Transient response; constant power load; model predictive control; disturbance observer; DC microgrid; bidirectional DC-DC converter; DC microgrid constant power load bidirectional DC-DC converter model predictive control disturbance observer
• ISSN: 2079-9292; 2079-9292
• DOI: 10.3390/electronics11091481

Despite its advantages over its AC counterparts, DC microgrids present a lot of challenges. One of these challenges is the instability issues caused by constant power loads (CPLs). CPLs deteriorate the system’s performance due to their incremental negative impedance characteristics. In this paper, a DC microgrid composed of a PV/battery system feeding a pure CPL was considered. A continuous-time model predictive control combined with a disturbance observer was applied to the DC–DC bidirectional converter. The purpose of the composite controller is to address the nonlinearity of the CPL and to maintain the stability of the system in a large operating region under load and PV generation variations. To show the performance of the system, several tests were performed under PV power and CPL power variations. Simulation results show good performance in terms of transient response, optimal tracking, and stability in a large operating region.