Medium Voltage Variable-Frequency Drive /Medium Voltage VFD

 GBP-H Four Quadrant Medium Voltage Variable Frequency Drive Principle

It is a special Medium Voltage Variable-Frequency Drive developed and produced by our company according to the operation requirements of mine hoist. This drive is based on the technology of series power unit and stack wave, high performance vector control technology as the core. This drive consists of rectifier phase shift transformer, power unit and control part.

The output voltage range from 3 kV to 10 kV, different output voltage is with different number of power units, 3 kV has 9 units, 6 kV has 15 units, 10 kV has 24 units, power units on each phase is connected in series and stack wave to increase voltage, the power units on the three-phase is connected by Y type, outputing rated voltage directly.

Powert units

The overall topology of the power unit is AC-DC-AC three-phase full-bridge rectifier, single-phase inverter output structure. Inside the power unit contains complete energy feedback circuit, DC filter circuit, inverter circuit, both rectifier side and inverter side are using controllable power electronic components IGBT, DC link is using electrolytic capacitance. Each power unit is equivalent to a AC-DC-AC voltage source type outputing single-phase low voltage VFD. The control board of power unit completes the high-speed communication with the control system through the optical fiber,  control the on-off of the IGBT, outputs the PWM waveform, and collects the fault and the state uploading to the control system, completes the work of the whole unit. Power unit is Modular design, which can be easily disassembled and installed integrally for convenient on-site fault handling.

 Excellent product performance

 ◆ Vector control technology, with the functions of zero-speed hovering, multi-machine synchronization, current limitation, etc.

 ◆ External output filter device is not necessary, with perfect harmonic-free characteristics.

 ◆ Zero speed with full torque output characteristics, avoiding the slippind, reduce mechanical impact, provide backup safety protection, redundant electrical braking system.

 ◆ Safe and reliable precharge design of low voltage circuit, decrease current impact, reduce VFD failure rate.

 ◆ High efficiency, the total efficiency of the system is over 96% under rated working conditions, of which the frequency conversion part efficiency is up to 98%.

 ◆ Wide input voltage range, more suitable for different grid conditions.

 ◆ No special requirements for motor, suitable for ordinary medium voltage motor, no length limit for motor cable.

 ◆ A comprehensive operation monitoring system with up to tens of thousands of operation log monitoring, can timely and accurately lock each fault points.

 ◆ Perfect self-diagnosis function.

 ◆ The grid power frequency feedback technology, reduce the VFD loss, improve the VFD service life.

 ◆ No need any filter devices before power unit to reduce the VFD volume.

 ◆ Power unit is controlled by fiber communication, which is complete electrical isolation to improve system security.

 ◆ power unit is modular structure which is interchangeable for quick disassembly and simple maintenance.

 ◆ With electrical constant deceleration function to minimize mechanical impact.

Model Selection and Dimensions of GBP Medium Voltage Variable-Frequency Drive