An improved H infinity controller using hybrid optimization for PV integrated MMC-HVDC system

Generally, circulating current is generated in a Modular Multilevel Converter (MMC) by fluctuations in the capacitor voltage of sub-modules. Therefore, this research work seeks to build the Photo Voltaic (PV) integrated MMC-High-Voltage Direct Current (HVDC) systems with optimal H-infinity controller which is appropriate for 3-phase system. To verify the unstable voltages of sub-modules, the reference current is initially set to zero, as well as the unstable currents in each phase are monitored with a current sensor as well as contrasted to the reference current, resulting in the generation of an incorrect circulating current. The main contribution is to reduce the error among the reference current as well as the actual circulating current. In the H-infinity controller, the gains are optimally tuned via a new hybrid algorithm referred as Jaya Optimization Insisted Explored Chimp (JOI-EC) algorithm, which is the hybridized version of the Jaya Optimization Algorithm (JOA) and the Chimp Optimization Algorithm (ChOA). Moreover, the performance of the proposed model is examined through control analysis, converter performance analysis, as well as capacitor voltage analysis in addition to the circulating current. The result of simulation shows the robust performance of the proposed controller with respect to minimum circulating current, voltage, and stability analysis.