Technical Analysis of High-Voltage Pulse Power Supply System Based on IGBT Stack and Pulse Transformer

Introduction

High-voltage pulse power systems are vital in fields like plasma source ion implantation (PSII), surface treatment, and semiconductor manufacturing. Traditional designs—such as those using hard tubes, thyratrons, or pulse forming lines (as shown in Figure 1)—often struggle with low efficiency, short lifespans, and limited flexibility. To overcome these drawbacks, this article examines a cutting-edge high-voltage pulse power system based on insulated gate bipolar transistor (IGBT) stacks and pulse transformers. By delving into its design principles, key components, and performance, we aim to showcase its technical strengths and offer insights for further optimization and advancement in related industries.

System Design and Technical Principles

This system features a modular setup, including a power supply module, IGBT stacks, a pulse transformer, high-voltage capacitors, protection circuits, and a control unit (see Figures 2 and 3). It works by using IGBT stacks to control capacitor charging and discharging, amplifying low-voltage pulses into high-voltage outputs through the pulse transformer to drive plasma loads. Here’s a breakdown of the core technologies:

1. IGBT Stack Design
   The IGBT stack acts as the system’s switching hub, with multiple IGBTs connected in series to manage high voltages (detailed in Figure 4). Its innovative driver circuit blends a few active drivers with passive components—like resistors, capacitors, and diodes—to synchronize multiple IGBTs. This simplifies the design, cuts costs, and uses voltage balancing circuits (e.g., RCD networks) to handle switching transients, protecting components. While reliable, high-frequency operations may introduce fluctuations due to parasitic effects, suggesting a need for refined circuit layouts to reduce interference.


2. Pulse Transformer and Voltage Amplification
   The pulse transformer boosts pulses to high voltages using a specific turns ratio, such as 6.6 (66/10, as per Table 1), with ferrite cores and oil cooling for stability. Simulations reveal that leakage (10 μH) and magnetizing inductance (3.3 mH) can cause waveform overshoot, pointing to the importance of fine-tuning inductance parameters. Enhancing core materials or winding designs could markedly improve pulse quality.


3. Protection Circuits and Safety
   To tackle arc issues in plasma loads, the system includes fast overcurrent detection and overvoltage protection. Diodes and capacitors absorb shutdown overvoltages, safeguarding switches, while an output diode blocks reverse voltage from the load (see Figure 3). This boosts stability in tough conditions, though response speed and heat management require attention to prevent long-term issues.


4. Control Unit and Flexibility
   The control unit adjusts pulse width (2–5 μs), repetition rate (10–2000 pps), and voltage amplitude (10–66 kV), meeting diverse needs (Table 1). Tests confirm stable performance across settings, highlighting adaptability. Adding smart controls, like adaptive algorithms, could further elevate its capabilities.


 

Performance Analysis and Technical Review

Testing a prototype validated the system’s performance. Here’s an evaluation of its key traits:

• Voltage Balance and Switching Characteristics
  Under resistive loads, the IGBT stack showed consistent voltage distribution, proving the balancing circuits’ effectiveness (simulated in Figure 5). Yet, switching transients—possibly from parasitic inductance or load effects—may spark electromagnetic interference or heat buildup. Optimizing layouts and driver signals could enhance stability.


• Output Waveform Characteristics
  The system delivers high-voltage (up to 66 kV), high-current (up to 100 A) pulses with short rise (1 μs) and fall (2 μs) times (Table 1). Waveform overshoot, likely due to leakage inductance and load capacitance interplay, suggests reducing leakage or tweaking load matching for better quality (Figure 5).


• Overcurrent Protection and Reliability
  In simulated arc scenarios, the protection circuit swiftly detected overcurrent, shut down the IGBT stack, and capped voltage spikes, ensuring safety. While this boosts reliability, heat accumulation in high-frequency or heavy-load cases could limit performance, calling for improved cooling.


 

Technical Discussion and Application Prospects

1. Technical Advantages
   Compared to traditional setups (Figure 1), this design shines with:
   • Efficiency and Durability: IGBTs’ fast switching cuts losses and extends lifespan.
   
   
   • Flexibility: Adjustable parameters suit various uses.
   
   
   • Modularity: Easy production, maintenance, and upgrades save costs.
   
   
    


2. Application Prospects
   This system promises broad impact in PSII, surface treatment, and semiconductor manufacturing. Its efficiency and flexibility make it a strong alternative to older designs, boosting ion implantation in PSII or delivering precise pulses for semiconductor processes. Its modular nature also allows tailoring to specific industrial needs.


3. Optimization Directions
   To push performance further, consider:
   • Transformer Optimization: Refine core and winding designs to cut leakage inductance and stabilize waveforms.
   
   
   • Thermal Management: Add liquid cooling or advanced heat dissipation for high-frequency switching.
   
   
   • Intelligent Control: Integrate AI or dynamic algorithms for smarter, adaptive operation.
   
   
    


 

Conclusion

This analysis of a high-voltage pulse power system based on IGBT stacks and pulse transformers underscores its standout design, technical execution, and performance. Its efficiency, durability, and flexibility position it as a contender in industrial and research arenas. Future tweaks in transformer design, thermal management, and smart controls could amplify its value. This article offers theoretical and practical guidance for advancing power electronics innovation.