According to the characteristic of the control loop, simple voltage control mode and basic PI compensation are employed to ensure the stability of the converter.
This PFC was realized by employing sliding-mode variable-structure inner current loop control and outer voltage loop PI control with digital low-pass filter to achieve high performance.
On above mentioned condition, a fuzzy-PI dual-mode adaptive speed control scheme is proposed, in which the control mode is selected momentarily according to the working condition.