Modulated Predictive Voltage Control of a Four-Leg Inverter with Fixed Switching Frequency

فاقد چكيده فارسي

This paper proposes a novel modulated model pre-dictive voltage control strategy for a two-level four-leg voltage source inverter with an output LC filter. To mitigate the coupling effects of state variables in a second-order LC filter and to im-prove the load voltage quality, the capacitor voltages and inductor currents are controlled simultaneously. The proposed controller predicts the state variables using the discrete-time model of LC-filtered four-leg inverter for 16 voltage vectors and evaluates them by a dual-objective cost function. The active and zero voltage vectors corresponding to the optimal cost function are synthesized by the three-dimensional space vector modulation, resulting in fast dynamic response, low steady-state error, and harmonic components centered around the fixed switching frequency. The feasibility of the proposed method is verified through simulation results considering balanced/unbalanced reference voltages and nonlinear loads. The performance of proposed controller is compared with the classical predictive voltage control during the transient and steady-state operating conditions.