Application of High-Voltage Pulsed Power Supplies in Gas Discharge
Gas discharge, a phenomenon involving complex physical processes such as ionization, excitation, and recombination, exhibits broad application potential in industry, environmental protection, scientific research, and other fields. High-voltage pulsed power supplies (HVPS), with their unique electrical characteristics, have become core devices for regulating gas discharge processes, playing an increasingly prominent role in optimizing discharge performance and expanding application scenarios. This article discusses the critical role of HVPS in gas discharge from three dimensions: technical principles, application scenarios, and development trends.
1. Technical Principles: Synergy Between Pulsed Characteristics and Discharge Processes
HVPS generate high-amplitude pulsed voltages in the nanosecond-to-microsecond range, creating non-uniform electric field environments in gas gaps. Compared with traditional DC or power-frequency power supplies, their core advantages are reflected in the following aspects:
1. Rapid Breakdown Capability: The steepness of the pulse front (typically at the kV/ns level) significantly reduces the breakdown delay time of gases, transforming gases from an insulating state to a conductive plasma state in extremely short time (nanoseconds). This feature is crucial for discharge scenarios requiring instantaneous high-energy input, such as plasma ignition and pulsed power device triggering.
2. Non-Equilibrium Plasma Regulation: The narrow pulse width (usually <1μs) limits the energy transfer time between electrons and heavy particles (ions, neutral molecules), forming non-equilibrium plasmas with high electron density (>10¹⁵ cm⁻³) and low gas temperature (close to room temperature). Such plasmas are rich in highly reactive particles (e.g., free radicals, excited molecules), making them suitable for scenarios requiring high chemical activity but strict control of thermal effects, such as waste gas treatment and biomedical sterilization.
3. Parameter Tunability: By adjusting parameters such as pulse frequency (10Hz-100kHz), peak voltage (10kV-100kV), and duty cycle (1%-50%), the electric field strength, energy deposition rate, and plasma lifetime in the discharge space can be precisely regulated, enabling flexible switching between discharge modes (e.g., corona discharge, dielectric barrier discharge, glow discharge).
2. Application Scenarios: Technical Breakthroughs and Practices in Multiple Fields
(1) Environmental Governance: The Core Driver for Efficient Pollutant Degradation
In the field of waste gas treatment, gas discharge technologies based on HVPS can remove pollutants through the following pathways:
Plasma Chemical Reactions: Free radicals such as ·OH and ·O generated by pulsed discharge oxidize volatile organic compounds (VOCs), decomposing them into CO₂ and H₂O;
Synergistic Catalytic Effects: The coupling of pulsed electric fields with catalysts (e.g., TiO₂, activated carbon) reduces the activation energy of reactions, improving the removal efficiency of acidic gases such as NOₓ and SO₂.
In practical applications, the narrow pulse characteristics of HVPS reduce energy conversion to heat, increasing energy efficiency by 30%-50% compared with traditional power-frequency power supplies and significantly lowering operating costs.
(2) Material Processing: The Technical Cornerstone of Low-Temperature Plasma Processing
In the field of surface modification, gas discharge driven by HVPS can produce the following effects:
Ion Bombardment and Activation: Pulsed electric fields accelerate ion streams to etch material surfaces or introduce functional groups, enhancing coating adhesion (e.g., pre-treatment of plastics before printing);
Thin Film Deposition Control: By adjusting pulse parameters, the energy distribution of particles in the plasma can be precisely controlled, enabling uniform deposition of nanoscale thin films (e.g., diamond-like carbon coatings).
Compared with DC power supplies, HVPS avoid thermal damage to materials caused by continuous Joule heating, making them suitable for processing heat-sensitive materials (e.g., polymers, biomedical materials).
(3) New Energy and Scientific Research: Innovative Tools for Cutting-Edge Fields
In nuclear fusion research, HVPS are used to drive gas discharge to generate plasma jets, simulating the high-temperature and high-pressure environments inside stars; in the new energy field, they can achieve efficient hydrogen production through pulsed discharge technology (e.g., plasma-assisted water splitting), with an energy conversion efficiency 20% higher than traditional electrolysis. Additionally, HVPS serve as synchronous trigger sources in gas discharge plasma diagnostics (e.g., emission spectroscopy, laser-induced fluorescence), providing precise time references for transient plasma parameter measurements.
3. Development Trends: Technological Innovations and Challenges
Currently, the application of HVPS in gas discharge is developing towards high frequency, integration, and intelligence:
Solid-State Device Innovations: The popularization of wide-bandgap semiconductor devices such as silicon carbide (SiC) and gallium nitride (GaN) has driven pulsed power supplies to higher frequencies (>100kHz) and higher efficiencies (>95%);
Multi-Field Coupling Technologies: Combining external fields such as magnetic fields and ultrasonic waves to optimize energy distribution in the discharge space and improve discharge stability in complex scenarios;
Intelligent Control Strategies: The introduction of machine learning algorithms enables adaptive adjustment of pulse parameters. For example, a breakdown voltage prediction model based on discharge current feedback can control the discharge delay error within ±5%.
However, issues such as high-voltage insulation design, pulse waveform distortion suppression, and system electromagnetic compatibility remain key bottlenecks restricting their large-scale application, which need to be addressed through material innovation and topological structure optimization.
Conclusion
HVPS provide core support for cross-disciplinary technological innovation by precisely regulating the spatio-temporal characteristics of gas discharge. With the deep integration of power electronics technology and plasma physics, their application boundaries in cutting-edge fields such as carbon neutrality, semiconductor manufacturing, and biomedicine will continue to expand. In the future, through multi-disciplinary collaborative research, HVPS are expected to become the core engine driving the development of gas discharge technology toward high efficiency and intelligence.
