Current output control strategy based on current reference feed-forward for H-bridge cascaded inverter

H-bridge cascaded inverter can be used for harmonic compensation in medium and high voltage systems. As the equivalent switching frequency is high, L-type filter is commonly used for H-bridge cascaded inverter. Meanwhile, considering device safety and filtering effect, inductance value of L filter is large. When the command current contains harmonics, especially high harmonics, large connecting inductance L increases the pressure of inner current control ring, and further results in larger current output error and slower response speed. To solve this problem, a harmonic current output control strategy based on current reference feed-forward, is proposed. By predicting the voltage drop on the connecting inductance, the pressure of inner current control ring can be reduced. As a consequence, the harmonic output performance of H-bridge cascaded inverter can be improved. Via theoretical analyses and simulation results, the feasibility and superiority of proposed strategy are verified.