Research on the Improvement of the Input Waveform of TT-1 Pulse Capacitor Charging Power Supply Based on APFC and Its Control

The TT-1 tokamak device is the first of its kind in the ASEAN region, in which the longitudinal field coil provides a strong toroidal magnetic field and requires a large amount of energy in the capacitor reserve. In the process of energy transfer from the grid to the load, it has been demonstrated that only the decomposed fundamental current in the distorted current waveform can effectively do work. This has a significant impact on the efficiency of energy transfer, resulting in a substantial reduction in efficiency. In this paper, an APFC circuit in continuous conduction mode is introduced for input-side sinusoidal waveform correction, and the control strategy of this circuit is analysed. The subsequent stage of the process is the construction of the feedback control loop. This is then compared with the conventional PI control for waveform correction, with active disturbance rejection control introduced as a comparator. The construction process of the control parameter reflects the stronger engineering physical quantity correlation of the active disturbance rejection control parameter adjustment. Simulation results verify that the APFC has a better correction effect on the intermittent rectified waveform and meets the total harmonic distortion rate requirement.