High-Precision Dual-Pulse Power Supply for Micro-Arc Oxidation: Taiwanese Client Acceptance Test Case
How we delivered a custom industrial pulse power solution meeting the strictest waveform and stability requirements.
Project Background & Requirements
This case study details the design, testing, and acceptance of a custom dual-pulse power supply system developed for a Taiwanese client specializing in micro-arc oxidation (MAO) processes. MAO requires highly controlled pulse voltage and current waveforms to ensure uniform coating quality and process repeatability.
The client specified the following non-negotiable requirements:
- High-frequency isolated design to meet safety and noise immunity standards
- Advanced DSP control for real-time waveform regulation
- Stable output voltage despite ±10% input line fluctuations
- Adjustable output frequency (10–1000 Hz) and duty cycle (0–100%)
- Waveform precision within ±2% of set parameters for critical MAO processes
Key Engineering Challenges
1. Ultra-High Waveform Precision Requirements
Unlike standard industrial power supplies, MAO processes demand precise pulse rise/fall times, flat-topped pulses, and minimal jitter. Even minor waveform distortions can lead to inconsistent oxide layer formation, compromising product quality. The client’s acceptance criteria required oscilloscope-verified waveforms with less than 1% overshoot and ±2% amplitude stability.
2. Input Voltage Fluctuation Immunity
Industrial facilities often experience unstable AC mains voltage, which can cause output voltage drift in conventional power supplies. The challenge was to design a system that maintains regulated output voltage even with significant line variations, without sacrificing waveform integrity.
3. System Modularity and Scalability
The client required a modular system architecture to accommodate future expansion. The power supply needed to support multiple parallel modules for increased power capacity while maintaining synchronized pulse outputs across all channels.
Our Engineering Solution
System Architecture
Imaxpower’s engineering team designed a modular dual-pulse power supply system with a high-frequency isolated topology, controlled by a Texas Instruments DSP processor. The architecture features independent power modules connected in parallel, synchronized by a central controller to ensure uniform pulse timing across all outputs.
Component Selection & Key Design Features
- High-Frequency Isolated DC/DC Converter: Provides galvanic isolation and noise suppression, meeting IEC 61010 safety standards for industrial equipment.
- DSP-Based Control Loop: 16-bit precision control with 10µs response time, enabling real-time adjustment of pulse parameters to maintain waveform accuracy.
- Active Voltage Regulation: Closed-loop feedback system compensates for input voltage fluctuations, maintaining output voltage stability within ±0.5%.
- Touchscreen HMI: User-friendly interface for setting pulse parameters (frequency, duty cycle, voltage, current) and monitoring real-time system performance.
| Parameter | Standard Industrial Pulse Supply | Imaxpower Optimized Solution |
|---|---|---|
| Waveform Precision | ±5% | ±2% |
| Input Voltage Fluctuation Tolerance | ±5% | ±10% |
| Pulse Rise Time | >5µs | <2µs |
| Modular Expansion | Limited (max 2 modules) | Up to 8 parallel modules |
| Jitter Control | ±50ns | ±10ns |
How to Select the Right Pulse Power Supply Configuration for MAO
Choosing the correct pulse power supply for micro-arc oxidation depends on three key factors:
- Process Requirements: Define the required voltage (typically 300–800V for MAO), current (10–1000A), and pulse parameters based on the material and desired coating properties.
- Waveform Precision: High-precision processes (e.g., aerospace components) require tighter control over rise/fall times and overshoot, while general industrial applications may tolerate wider tolerances.
- Environmental Conditions: Facilities with unstable mains power require enhanced line regulation, while high-noise environments demand isolated topologies and EMI filtering.
Measured Results & Client Acceptance
During the factory acceptance test (FAT), the system was validated using a ZDS2024 Plus digital oscilloscope to measure pulse waveforms, voltage stability, and parameter accuracy. Key test results included:
- Waveform Integrity: Oscilloscope verification confirmed pulse overshoot <1% and rise time <2µs, exceeding the client’s requirements.
- Input Fluctuation Test: Output voltage remained stable within ±0.3% during ±10% input voltage variations.
- Long-Term Stability: 72-hour continuous operation test showed no drift in pulse parameters, with all modules synchronized within ±5ns.
The client’s engineering team reviewed the test data and oscilloscope traces, confirming the system met all acceptance criteria. The modular design and high precision were highlighted as key differentiators compared to competing solutions.
Key Lessons Learned
This project reinforced three critical lessons for designing industrial pulse power supplies:
- Waveform precision is non-negotiable for advanced surface treatment processes. Even minor deviations can impact product quality, requiring DSP-based closed-loop control and high-speed feedback systems.
- Modular design is essential for scalability and maintenance. Parallel power modules allow for easy expansion and hot-swap capability, reducing downtime in industrial environments.
- Client-side acceptance testing must include real-world conditions. Testing under simulated line fluctuations and continuous operation ensures the system performs reliably in the client’s facility.
Need a Custom Pulse Power Supply for Your Industrial Process?
Our engineering team designs and manufactures high-precision pulse power solutions for micro-arc oxidation, plasma treatment, and other industrial applications. Send us your project specifications, and we’ll provide a tailored solution within 24 hours.
Frequently Asked Questions
Q: What is the typical voltage range required for micro-arc oxidation processes?
A: MAO processes typically require voltages between 300–800V, with currents ranging from 10–1000A depending on the part size and coating requirements. Imaxpower’s pulse power supplies can be customized to meet specific voltage and current needs.
Q: How does a high-frequency isolated design improve pulse power supply performance?
A: High-frequency isolation provides galvanic separation between the mains and the load, reducing electrical noise and improving safety. It also allows for tighter control of output waveforms and better line regulation, even with unstable input power.
Q: Can Imaxpower’s pulse power supplies be integrated with existing production lines?
A: Yes, our systems feature standard communication interfaces (Modbus, RS485, Ethernet) for seamless integration with industrial control systems. We also offer custom HMI and software solutions to match existing production workflows.
About IMAXPWR
IMAXPWR is a national high-tech enterprise specializing in the R&D, manufacturing, and customization of industrial power conversion equipment, including pulse power supplies, energy storage converters, and bidirectional DC/DC modules. With a team of engineers from leading power electronics companies, we deliver reliable, high-performance solutions for industrial, renewable energy, and microgrid applications.
Our products are certified to CE, UL, and RoHS standards, and we provide OEM/ODM services tailored to client-specific requirements. For more information, visit imax-pwr.com or contact our engineering team at info@imaxpwr.com.
Note: This case study is based on typical project configurations and industry experience for illustrative purposes. Actual performance may vary based on specific process conditions and client requirements.
