Heavy Duty MAO Plating Power Supply (750V/100A) by GAOHUI for Micro-arc Oxidation PEO

For engineers and manufacturing directors pursuing uncompromising ceramic coating density and throughput, you have found the definitive power source. The GAOHUI 75kW Micro-arc Oxidation (MAO) System is not a generic rectifier; it is a precision-engineered pulse response unit designed specifically for the harsh, high-impedance demands of plasma electrolytic oxidation (PEO). We deliver the exact energy signature required for forming a high-quality magnesium alloy ceramic coating and titanium bio-compatible oxide layers directly on your workpiece.
Part 1 Key Features & Engineering Highlights
This industrial high frequency rectifier factory solution prioritizes arc suppression and density control above all else. Unlike standard anodizing units that struggle with the unstable discharge of MAO, the GAOHUI 750V/100A system uses third-generation soft-switching IGBT technology to maintain stable micro-arc plasma even at the transition to the hard sparking zone.
Precision Voltage Slew Control: The unit automatically adjusts voltage from 0V to 800V based on real-time load impedance. This prevents the catastrophic “arc death” common in cheap units when the oxide layer thickness changes.
Ultra-Fast Pulse Response: Achieves 1-3000Hz adjustable pulse frequency with true square wave output. This specific waveform is critical for achieving uniform coating porosity on aluminum and magnesium alloys.
High Current Density Management: Delivers a full 100A continuous output without derating at 50°C ambient. The heavy-duty busbars and liquid-cooled IGBT banks ensure consistent performance over long MAO cycles.
GaN / SiC Ready Platform: The control architecture is designed for next-gen semiconductor efficiency, ensuring your investment is future-proof for process development.
Part 2 Technical Specifications Table
| Parameter | GAOHUI MAO-75100 Specification | Notes |
| :— | :— | :— |
| Output Voltage | 0 – 800V DC (Nominal 750V) | Automatic impedance matching |
| Output Current | 0 – 100A DC (Max) | 5A, 30A, 50A, 200A, 500A also configurable |
| Total Power | 75kW | Continuous duty (100% rated) |
| Input Voltage | 380V AC ±10%, 3-Phase | Custom AC inputs available |
| Pulse Frequency | 1 – 3000 Hz | Fully adjustable |
| Duty Cycle | 1% – 99% | Controlled in 0.1% increments |
| Ripple | < 1% at rated output | Pure DC mode available |
| Cooling Method | Forced Air or Water-Cooled | Water-cooled recommended for high-duty cycles |
| Protection Class | IP54 (Control Panel) / IP20 (Power Unit) | Environment hardened |
Part 3 Advanced Built-in Protection Systems
Industrial reliability is non-negotiable. The GAOHUI system features a holistic protection architecture that monitors over 15 parameters in real-time.
Arc Fault & Glow Discharge Detection: A proprietary algorithm differentiates between normal MAO microlightning and destructive arc tracking. The system instantly shuts down or enters a "blanking" mode to extinguish the arc.
Real-Time Load Disconnect: Electronic circuit breaker isolates the output in under 5 microseconds if an open circuit or short circuit is detected, protecting both the rectifier and the workpiece.
Thermal Runaway Prevention: Multiple NTC sensors on the IGBT modules and rectifier diodes trigger an active derating algorithm or emergency shutdown before semiconductor junction temperatures reach critical limits.
Part 4 Target Industrial Applications
This power source is the core of your surface treatment line. It is precisely engineered for:
Plasma Electrolytic Oxidation (PEO) of Magnesium Alloys: Essential for industries needing lightweight, corrosion-resistant parts for aerospace and automotive. The GAOHUI system delivers the specific current-voltage curve required for stable ceramic layer growth on AZ31, AZ91, and WE43 grades.
Micro-arc Oxidation (MAO) of Aluminum Alloys: Achieve high-hardness, grey-white ceramic coatings on 6061, 7075, and 2xxx series alloys. Ideal for manufacturing components for 3C electronics, precision tools, and military equipment.
Titanium Bio-Compatible Oxide Formation: For medical implant manufacturers requiring controlled oxide thickness and porosity, the 750V capability allows for the creation of customized titanium dioxide surfaces for orthopedic and dental implants.
Hard Anodizing & Electrolytic Coloring: While optimized for MAO, the unit also performs exceptionally as a standard anodizing rectifier for Type II / Type III processes on aluminum.
Part 5 Customization and Tailored Engineering Services
We are not a distributor of standard boxes. Our Changzhou factory treats every order as a custom build. We configure the IGBT rectifier manufacturer design to your exact process line. Want a specific heavy-duty DC power supply price for your budget? We provide a transparent cost structure based on your exact module requirements.
Our engineering department can modify any unit to your specs.
Electrical Configuration: Custom output voltage from 1V-1000V and output current from 1A-100,000A. All units are AC Input to DC Output only. We can integrate an automatic reversing polarity cycle (0-999 seconds) to strip metal plating or invert the cell polarity for specialized PEO pre-treatments.
Process Control Integrations:
Ampere-Minute Integrator: Precisely stop the process at a specific charge density for repeatable coating thickness.
Multi-Stage Profile Control: Program a 10-step recipe including initial soft-start, ramping voltage, hold time, and auto-shutdown.
Pulse Functions: 1-3000Hz adjustable in DC unipolar, DC bipolar (asymmetric), and DC pulsed modes.
Load Sharing / Redundancy: Master-slave configuration for large 500kW lines. Slave units automatically take over if a master fails.
We deliver full customizable software control, hardware dimensions, and front-panel layouts per your OEM requirements. Contact us for a specific custom current voltage rectifier configuration for your magnesium alloy ceramic coating line.