Research on a High-Frequency High-Voltage Plasma Power Supply Based on SPWM Modulation

Plasma power supplies find extensive applications across industrial, energy, environmental, and medical domains. This study addresses limitations of conventional plasma power supplies, including high harmonic current content, neutral-point potential imbalance, and manufacturing complexity. A novel design approach for high-frequency, high-voltage plasma power supplies is proposed, based on three-level sinusoidal pulse width modulation (SPWM) technology. First, the design distinctions between the input-side Boost power factor correction circuit and Diode Rectifier circuits are analyzed. Subsequently, an integrated SPWM driver-controller architecture and a design methodology for high-frequency transformers are introduced. A single-phase three-level SPWM modulation strategy is then presented. Based on this modulation technique, a high-frequency, high-voltage plasma power supply prototype incorporating air pumps and rotary motors was developed. Experimental validation demonstrated stable generation of plasma gas at a frequency of 25 kHz, with an output voltage of 10.79 kV and an output power of 1.75 kW. Results indicate that the refined power supply enhances electrical utilization efficiency, resolves neutral-point imbalance issues, and simplifies manufacturing through its integrated driver-controller design. This work offers a valuable reference for advancing high-frequency, high-voltage plasma technologies.