Micro-arc Oxidation MAO Power Source 750V 100A GAOHUI Plasma Electrolytic Oxidation Rectifier

EXECUTIVE SUMMARY
This 75kW GAOHUI Micro-arc Oxidation power source is engineered specifically for the plasma electrolytic oxidation (PEO) process, also known as micro-arc oxidation (MAO). Delivering a pure DC pulsed output at 750V and 100A, this rectifier generates the high-energy plasma necessary to instantaneously convert the surface of lightweight metals—such as aluminum, magnesium, and titanium—into a dense, crystalline ceramic oxide layer. Unlike conventional anodizing rectifiers which operate in a lower voltage regime, this unit is designed to sustain the dielectric breakdown required for creating superior hard, wear-resistant coatings on applications like magnesium alloy ceramic coating and titanium bio-compatible oxide surfaces. As a dedicated industrial high frequency rectifier factory, GAOHUI ensures this unit provides the precise duty cycle control and pulse shaping needed for consistent, repeatable MAO results.
PART 1 KEY FEATURES & ENGINEERING HIGHLIGHTS
Pulse Precision for Plasma Coating
This power source deploys advanced IGBT switching technology to generate unipolar pulses at adjustable frequencies from 1Hz up to 3000Hz. This level of pulse control allows operators to fine-tune energy delivery per spark event, ensuring uniform coating thickness without thermal damage to the base metal. The built-in multi-stage profile controller enables programming sequential voltage and current ramps, a critical requirement for the growth phases of magnesium alloy ceramic coating and PEO on valve metals.
Domain-Specific Voltage Capability
While the nominal spec is 750V, this unit can deliver a ceiling voltage of 800V, ensuring a significant headroom for maintaining the plasma arc even under heavy load on complex geometry parts. It provides the distinct advantage of constant current (CC) and constant voltage (CV) switching modes, automatically adjusting as the dielectric barrier forms. For projects demanding heavy-duty DC power supply price efficiency, this robust architecture minimizes energy waste per layer.
Robust Industrial Enclosure
The system is housed in a rugged, forced-air cooled cabinet optimized for industrial environments. It integrates a digital Ampere-Minute integrator for precise chemical consumption tracking and offers an automatic reverse polarity (ARP) module for periodic duty cleaning of the cathode. All control logic is housed on a shock-resistant PLC platform.
PART 2 TECHNICAL SPECIFICATIONS TABLE

PART 3 ADVANCED BUILT-IN PROTECTION SYSTEMS
Designed to operate within highly reactive plasma baths, this IGBT rectifier manufacturer integrates a suite of protective circuits to shield both the equipment and the work piece. Safeguards include over-voltage clamping, instantaneous over-current cutoff (electronic fast trip), thermal overload protection (sensors on main IGBT banks), and a dry-run / low electrolyte level input trigger. The system also features an arc detection circuit that suppresses spurious micro-arcs outside the intended treatment zone, preventing surface burn marks. An emergency stop (E-stop) overrides all digital logic for safe physical shutdown.
PART 4 TARGET INDUSTRIAL APPLICATIONS
This power source is the standard tool for industries demanding bio-compatible oxide layers and high-wear ceramic surfaces:
– Plasma Electrolytic Oxidation PEO: For aluminum 6061 and 7075 aerospace structural components requiring high corrosion resistance.
– Magnesium Alloy Ceramic Coating: Superior protection against galvanic corrosion for automotive transmission housings, drone bodies, and electronics chassis.
– Titanium Bio-Compatible Oxide: Producing a thick, porous TiO2 layer ideal for dental implants and orthopedic load-bearing joints.
– Customized Surface Treatments: Applications requiring the deposition of thick oxide layers ( > 50 microns) through controlled dielectric breakdown, impossible with standard anodizing.
PART 5 CUSTOMIZATION AND TAILORED ENGINEERING SERVICES
GAOHUI recognizes that every MAO electrolyte chemistry and part geometry demands specific electrical waveforms. We offer complete customization on every custom current voltage rectifier. Our factory’s design capacity spans from 1V to 1000V and 1A to 100,000A output. Input is AC (typically 3-phase), output is filtered DC only. We configure your unit with optional process modules including:
– Process Timer & Multi-Stage Profile Control: Define up to 16 discrete steps of voltage, current, frequency, and duration.
– Ampere-Minute Integrator: Closed-loop control based on accumulated charge for consistent pore size and density.
– Automatic Reverse Polarity (ARP): Short, high-energy reverse pulses to clean the cathode of conductive precipitates.
– Soft-Start: Gradual power application prevents arcing on contact with the bath.
– Advanced Communication Interfaces: RS485 Modbus RTU protocol, Ethernet/IP for full SCADA integration, isolated 4-20mA analog reference, and dedicated Pulse Function input (1-3000Hz adjustable via external signal generator).