Vacon NXP Common DC Bus products – Providing ultimate flexibility

Vacon offers a comprehensive range of Common DC bus drive products comprising front- end units, inverter units and brake chopper units in the entire power range and voltages from 380 V to 690 V. The drive components are built on proven Vacon NX technology and provide the ideal energy sharing solution for a multitude of power systems.

Vacon Common DC bus components are used in a multitude of combinations across a wide spectrum of high-power process industries from the pulp & paper, steel, metal & mining and marine cranes to smaller machines and production lines, which also demand cost-effective solutions.

Flexible configuration, customized solutions

Common DC bus components can be used in a multitude of combinations. In a typical DC bus configuration, the drives that are generating can transfer the energy directly to the drives in motoring mode. Common DC bus drive systems have different kinds of front-end units to meet the requirements of the electricity network and the process where the drives are used. The front-end units convert a mains AC voltage and current into a DC voltage and current. The power is transferred from the mains to a common DC bus and, in certain cases, vice versa. With the right configuration, the drive system can achieve optimal performance and significant energy savings can be made when braking energy is utilized to its full potential.

Active front-end (AFE)

The AFE unit is a bidirectional (regenerative) power converter for the front-end of a common DC bus drive line- up. An external LCL filter is used at the input. This unit is suitable in applications where low mains harmonics are required. AFE is able to boost DC link voltage (default +10%) higher than nominal DC link voltage (1,35x Un). AFE needs an external pre-charging circuit. However, AFE does not need any external grid side measurements to operate. AFE units can operate in parallel to provide increased power and/or redundancy without any drive to drive communication between the units. AFE units can also be connected to the same fieldbus with inverters, and controlled and monitored via fieldbus.

Non-regenerative front-end (NFE)

The NFE unit is an unidirectional (motoring) power converter for the front-end of a common DC bus drive line-up. The NFE is a device that operates as a diode bridge using diode/thyristor components. A dedicated external choke is used at the input. The NFE unit has the capacity to charge a common DC bus, thus no external pre-charging is needed. This unit is suitable as a rectifying device when a normal level of harmonics is accepted and no regeneration to the mains is required. NFE units can be paralleled to increase power without any drive to drive communincation between the units.

Inverter unit (INU)

The INU (Inverter unit) is a bidirectional DC-fed power inverter for the supply and control of AC motors. The INU is supplied from a common DC bus drive line-up. A charging circuit is needed in case the connection possibility to a live DC bus is required. The DC side charging circuit is integrated for powers up to 75 kW (FR4-FR8) and externally located for higher power ratings (FI9-FI14).

Brake chopper unit (BCU)

The BCU (Brake chopper unit) is a unidirectional power converter for the supply of excessive energy from a common DC bus drive line-up to resistors where the energy is dissipated as heat. External resistors are needed. By using two brake resistors, the braking power of the brake chopper is doubled.

Key benefits

  • Same software tool, same control option boards allowing the maximum utilization of NXP features over a wide power range.
  • No additional modules required. Option boards are compact and easy to install at any time.
  • Optimized drive system configurations enabling minimized overall investment cost. Excessive braking energy can be fed back to network saving energy costs.
  • Optimized module design reduces need for additional engineering and saves in cabinet space reducing overall costs.

Technical highlights

  • Full power (0.55 to 2.2 MW) and voltage (380 to 690V) range for both induction and permanent magnet motors.
  • Five built-in expansion slots for additional I/O, fieldbus and functional safety boards.
  • Low harmonic regenerative front end. Cost effective non-regenerative front end.
  • Compact drive modules and easy integration to cabinets.

Typical applications

  • Continuous web systems
  • Metal lines eg. roller table systems
  • Winders &unwinders
  • Crane systems eg. main hoists, gantry & trolley drives
  • Centrifuges
  • Winches
  • Conveyors
  • Excavators
NXP Common DC Bus Products

NXP Common DC Bus Products