Our Medium Voltage Variable Frequency Drives (MV VFDs) are advanced motor control solutions designed to deliver precise speed regulation, high efficiency, and superior performance for a wide range of industrial applications. Engineered with robust technology and compliance with international standards, our MV drives ensure reliable operation in demanding environments.

Technical Specifications:

• Voltage Range: 3.3 kV to 13.8 kV

• Power Range: 150 kW to 100,000 kW

• Standards Compliance: IEEE 519-1992, GB/T14549-1993

• Topology: AC–DC–AC with IGBT technology

Key Features:

• No Additional Input Filters Required – Built-in harmonic performance eliminates the need for external filtering

• High Power Factor Operation – Reduces reactive power and eliminates the need for power factor correction devices

• Energy Efficient – Optimized motor control reduces energy consumption and operational costs

• Modular Power Cell Design – Enhances reliability, scalability, and ease of maintenance

• Series-Connected Power Cells with voltage overlapping for improved performance and redundancy

• Isolated Transformer Input providing phase-shifted supply to minimize harmonic distortion

• Advanced IGBT Switching Technology ensures high reliability and efficiency

Working Principle:

The MV VFD operates on an AC–DC–AC conversion system, where input AC power is converted to DC and then inverted back to controlled AC output using IGBT-based switching. Multiple power cells connected in series per phase, supplied via an isolated transformer with phase-shift windings, allow flexible voltage scaling and improved waveform quality.

Types of MV VFD

1. General Purpose VFD

Designed for energy-saving applications, this drive adjusts motor speed to match load requirements. It is widely used in:

• Pumps

• Fans

• Power plants

• Mining

• Petrochemical

• Metallurgy

• Cement

• Municipal systems

2. High-Performance VFD

This advanced solution incorporates vector control and regenerative technology, delivering:

• Constant torque performance

• High dynamic response

• Precise speed and process control

• Wide speed regulation range

• Fast braking capability

• Regenerative energy feedback to the grid

Applications include:

• Mining hoists

• Conveyors

• Rolling mills

• Marine systems

• Heavy-duty industrial machinery

System Components

Transformer Cabinet:

• Isolated multi-winding transformer providing independent phase-shifted supply

• Reduces harmonic distortion and improves input current waveform

• Configurable cooling system for dry-type transformers based on power rating

Power Cell Cabinet:

• Controller: Voltage vector PWM control with optical fiber communication ensuring complete electrical isolation

• Power Cells: Modular and replaceable design for ease of maintenance

• I/O Board: Supports digital and analog interfaces for flexible integration

• HMI Interface: Multi-language LCD display for parameter settings, monitoring, and fault diagnostics

Optional Bypass Cabinet:

• Manual or automatic bypass system ensures continuous operation during VFD maintenance or faults

• Allows motor to run directly on grid supply when required

Advantages:

• No need for additional output filters

• Direct control of both synchronous and asynchronous motors

• No motor derating required

• Eliminates dV/dt stress on motor insulation and cables

• No torque ripple, extending motor and equipment lifespan

• No cable length restrictions within acceptable voltage drop limits

For further technical details, customization options, or project-specific requirements, please contact us to find the most suitable Medium Voltage VFD solution for your application.