Simplified variable band hysteresis current control for grid-connected inverter

Because switching frequency of the fixed band hysteresis current controller varies greatly, it is more difficult to design the output filter. Although variable band hysteresis control can achieve fixed switching frequency, it requires more processor resources when it is actualized by software. This paper analyzes the changing patterns of switching frequency by transient current equation, and replaces sinusoidal band with triangular band to simplify the corresponding software design under the premise of little change of switching frequency. Simulation results show the feasibility of this method.