Adaptative fast AC voltage regulation using a resonant current controller

Some recent papers describe a new resonant current controller (RCC) which is well suited for voltage supply inverters (VSI) current control. It is an alternative to the hysteresis current controller (HCC). Its specifications are fast response, very low sensitivity to the load´s electrical parameters, extremely low DHT and a maximum inverter switching frequency firmly controlled. This novel modulator combines two structures: the first acts at lower frequencies for current regulation and the second acts at higher frequencies for switching frequency control by means of a voluntary resonant mode. In this paper, we study an AC voltage regulation involving the RCC which controls the VSI added LC low-pass filter input current. But the investigated voltage control modifies the voltage gain. Indeed, when involving a high proportional gain value, we decrease the system static error, but this can make the closed loop unstable. Thus, to avoid this phenomenon the voltage gain is automatically checked. Thereafter, experimental results agree and demonstrate the excellent behavior of this voltage regulator.