A Digitally Controlled High-Voltage DC Power Supply System Applied to Ion Pump Discharge

The ion pump is the key equipment for maintaining the vacuum environment. Driven by a high-voltage DC power supply, a strong electric field is established between the cathode and anode plates inside the ion pump, ionizing gas molecules and accelerating ion movement. This efficiently maintains the vacuum environment and dynamic equilibrium. The power supply characteristics of the ion pump require it to automatically adjust the output voltage and current according to changes in the vacuum level. In this paper, the engineering implementation of a digitally controlled high-voltage DC power supply system for ion pumps is studied. The overall architecture of the digital control system is constructed, and three operating modes constant voltage, constant power, and constant current are defined. Based on the full-bridge LLC resonant topology, the transformer design is optimized and the doubled-voltage rectifier network is cascaded to complete the design of the main power conversion unit. To address the wide-range power supply requirements of ion pump loads, a control method based on “narrow pulse width” pulse frequency modulation is proposed to achieve stable closed-loop control across all operating points. Finally, a hardware platform with an output voltage of 0–7 kV, an output current of 0–100 mA, and a maximum power of 200 W is built to verify the feasibility of the system structure design.