In the field of power electronics, high-voltage series resonant technology for voltage-source inverters is gradually becoming a research hot spot. This technology achieves efficient energy conversion in high-voltage environments through ingenious application of the resonance principle, providing a brand-new solution for modern power systems. This article will delve into the principle characteristics, system composition, control strategies, and practical application scenarios of this technology, helping readers gain a comprehensive understanding of this cutting-edge technology.
I. Analysis of Technical Principles and Characteristics
The core of the high-voltage series resonance technology for voltage-source inverters lies in the utilization of the characteristics of the LC series resonance circuit. When the output frequency of the inverter matches the natural frequency of the resonance circuit, the system enters a resonant state, at which point the circuit impedance is minimized and only pure resistance characteristics are exhibited. This operating state brings three significant advantages: Firstly, in the resonant state, the voltage and current are in phase, achieving an ideal power factor of 1. Secondly, during resonance, the energy storage of the inductor and capacitor cancel each other out, significantly reducing the reactive power demand. Finally, the resonance amplification feature enables high-voltage output even with a relatively low input voltage.
Compared with traditional hard-switching technology, this technology has obvious performance advantages. Its switching loss can be reduced by more than 60%, and the electromagnetic interference level can be decreased by about 40 dB. Meanwhile, the system efficiency can generally reach over 95%. These advantages make this technology irreplaceable in high-voltage and high-power applications. Notably, in the resonant working state, the switching process of power devices achieves zero-voltage or zero-current conversion, which fundamentally solves the problem of high switching loss in high-voltage applications.
II. System Composition and Key Components
The complete voltage-source inverter high-voltage series resonant system is composed of several key subsystems. The power conversion section adopts full-bridge or half-bridge topology, and IGBT or MOSFET is selected as the switching device according to the output voltage level. The resonant network is usually composed of high-voltage capacitors and adjustable inductors, among which the capacitors need to have high withstand voltage and low loss characteristics, while the inductors require good linearity and high Q value. The control unit adopts a DSP + FPGA architecture to achieve relatively precise frequency tracking and power regulation.
In terms of system protection, multiple protection mechanisms have been designed. Overvoltage protection employs a crowbar circuit, which can respond within microseconds; overcurrent protection is achieved through real-time monitoring by Hall sensors; and temperature protection is implemented by deploying multiple temperature sensors at critical nodes. These protection measures collectively ensure the safe operation of the system in high-voltage environments. Notably, modern systems have also introduced intelligent predictive protection algorithms, which can predict abnormal states tens of milliseconds in advance, significantly enhancing system reliability.
III. Control Strategies and Technical Challenges
To achieve stable high-voltage series resonant operation, three major control challenges need to be addressed: frequency tracking, power regulation, and anti-interference. Currently, the mainstream control methods include phase-locked loop control, fuzzy adaptive control, and neural network control, etc. Phase-locked loop control adjusts the switching frequency by real-time detection of the phase difference at the resonant point, with a dynamic response time that can be controlled within 100 μs. Fuzzy adaptive control can automatically adapt to load changes and keep the system always operating in the optimal state.
The technical challenges mainly lie in high-voltage insulation and electromagnetic compatibility. Under working voltages above 10kV, the problem of partial discharge is particularly prominent. Solutions include the use of special insulating materials and the optimization of electric field distribution design. The issue of electromagnetic interference is addressed through multi-layer shielding and optimized wiring. New research has also found that paralleling an appropriate small resistor across the resonant capacitor can effectively suppress high-frequency oscillations, providing a new approach for enhancing system stability.
IV. Typical Applications and Prospects Outlook
This technology has been successfully applied in multiple important fields. In the medical equipment sector, it is used in high-end CT machines and proton therapy devices, where the stability of the high-voltage power supply system directly affects the imaging quality and treatment outcome. In the industrial field, it is mainly applied in environmental protection equipment such as electrostatic precipitators and ozone generators, offering energy savings of over 30% compared to traditional technologies. In the scientific research field, it provides high-performance high-voltage power supplies for particle accelerators, nuclear fusion devices, and other equipment.
The future development trends are mainly reflected in three aspects: first, the development towards higher voltage levels, with the goal of breaking through the 100kV technical bottleneck; second, the improvement of intelligence, combining digital twin technology to achieve remote monitoring and predictive maintenance; third, the increase in system integration, reducing the volume by more than 50% through new packaging technologies. With the mature application of wide bandgap semiconductor devices, this technology is expected to achieve new breakthroughs in efficiency and power density.
V. Case Study Analysis
Taking a certain type of 100kW/20kHz high-voltage series resonant power supply as an example, its technical indicators have reached the international advanced level. This system uses SiC MOSFET as the switching device, with a working voltage of 15kV and an efficiency of 96.5%. The key innovation lies in the adoption of an adaptive resonant frequency tracking algorithm, which can maintain stable output even when the load changes by ±30%. Actual operation data shows that compared with the traditional solution, it saves more than 500,000 yuan in electricity costs annually and reduces maintenance costs by 70%.
Another successful case is the plasma power supply system used in semiconductor manufacturing. This system achieves a 40kV output through the series connection of multiple modules, and adopts fiber-optic isolated drive and distributed control architecture, solving the problems of high-voltage isolation and synchronous control. Actual production has proven that this system has improved the uniformity of wafer processing by 15% and increased production capacity by 20%, providing key support for breakthroughs in chip manufacturing processes.
The high-voltage series resonance technology of voltage-source inverters represents the cutting-edge direction of high-voltage power supply development. Its outstanding performance indicators and broad application prospects are inspiring. With the continuous emergence of new materials and new devices, this technology is bound to have a broader development space. In the future, it is necessary to further strengthen basic research, break through key technical bottlenecks, and at the same time pay attention to the cooperation among industry, academia and research institutions, accelerate the transformation of technological achievements, and provide strong support for the development of China’s high-end equipment manufacturing industry.
Post time: Dec-10-2025