A Phase-shifting Control IPOS High-voltage Generator with Low Output Voltage Ripple for X-Ray

Abstract

A high-voltage (HV) generator with phase-shifting closed-loop control for X-ray is proposed. The LCC topology with input parallel output series (IPOS) is used in the circuit, and the phase-shifting closed-loop control is adopted to reduce the output voltage ripple further. In this paper, the LCC resonant converter is modeled based on fundamental harmonic approximation (FHA), and the output voltage ripple of a single module transformer is derived. On this basis, the output ripple of the multi-module LCC cascade converter is calculated and analyzed. Aiming at the problem that the ripple cancellation effect deteriorates due to the inconsistent parameters between modules, a phase locked loop (PLL) phase-shifting closed-loop control strategy is proposed. The simulation and experiment results show that the control method is feasible and reasonable.