Model predictive control of an AC-to-AC converter with input and output LC filter

The use of finite state model predictive control (FS-MPC) is investigated for an AC-to-AC converter with LC output filter for voltage regulation applications. The equivalent input inductance of the source is included in the model of the converter which results in a second equivalent LC filter at the input. This introduces oscillations in the system. FS-MPC is used to add control to the input without the need for complex control loops. Furthermore, evaluating and switching the system at equidistant instants in time, causes the average switching frequency to decrease for certain voltage references. A new prediction method is proposed to maintain the average switching frequency, which improves the THD of the output voltage. Simulation results are provided to verify the performance of the proposed prediction method.