Model Predictive Control of Dual-Mode Operations Z-Source Inverter: Islanded and Grid-connected

This paper presents a model predictive control (MPC) of dual-mode z-source inverters with capability to operate in islanded and grid-connected mode. The transition from islanded to grid-connected mode and vice versa can cause significant deviation in voltage and current due to mismatch in phase, frequency, and amplitude of grid voltage and load voltage. This paper proposes a seamless transition from different modes of operations of z-source inverter using the concept of MPC. The main predictive controller objectives is direct decoupled power control in grid-connected mode and load voltage regulation in case of islanded mode. Direct decoupled active and reactive power control in grid-connected mode enables the proposed power electronics interface to behave as a power conditioning unit for ancillary services such as reactive power compensation. The proposed controller features simplicity, seamless transition between modes of operations, fast dynamic response, and small tracking error in steady state condition of controller objectives. The operation of the proposed system is verified experimentally.