Phase-Shift Control Analysis of a 25 kV DC Supply Utilizing Voltage Multiplier

This paper introduces an analysis of a phase-shift control technique for the generation of high DC voltage using a two-stage half-wave Cockcroft-Walton multiplier. In high-voltage applications, the phase shift technique edge over Pulse Width Modulation (PWM) due to its high voltage gain, ability to minimize switching losses with zero-voltage switching (ZVS), and capacity to generate a three-level voltage signal in contrast to PWM's traditional two-level signal. This approach effectively reduces stress on switching devices, enhances overall efficiency, and it also produces lower electromagnetic interference (EMI) due to smoother transitions. The stability under phase-shift control stability is challenging over the PWM method; however, its advantages make it suitable for high-voltage applications in air purification, microwave, and terahertz (THz) generation. The designed topology containing a five-stacked voltage multiplier is simulated to generate a voltage of up to 25 kV using a phase-shift controlled full bridge inverter circuit. The performance of the proposed phase-shift control strategy is verified on a miniaturized hardware prototype at a fixed load.