Variable speed drive (VSD) manufacturers are moving away from offering multiple options and add-ins to their core product according to REO UK.
Instead they are encouraging end users to source equipment such as input mains chokes and filters, DC link braking resistors and output dv/dt filters, sinusoidal filters and motor chokes independently.
This is to be welcomed by VSD users as they are now able to more easily compare like for like without the issue being clouded by basic inverter variations. To address this trend REO has launched its REOunity range of wound components.
When the European Electromagnetic Compatibility (EMC) Directive and the G5/4 recommendation were introduced VSD manufacturers clamoured to offer radio frequency interference (RFI) filters and chokes as part of a product range complete with ancillary components. More recently, drives manufacturers have been distancing themselves from offering anything other than a standard range of core products with minimum essential EMC requirements.
The onus is now on OEMs, systems integrators, machine builders and end users to determine the EMC requirements at the site where the VSD equipment is being commissioned. This simplifies the comparison process for users when choosing between different VSDs and makes the buying decisions for OEMs and machine builders a little more straightforward.
REO has launched the REOunity range of resistive and inductive wound components, available from stock. The range is compatible with all VSDs and can be easily integrated into most systems.
REOunity includes variants for ingress protection (IP) and liquid cooling, which can reduce component size by more than half. Many renewable and marine applications are moving towards water cooling, because it offers superior environmental protection for drive systems. The heated water produced can also be easily recycled.
REOunity offers a number of solutions for VSD users and OEMs, including line reactors and harmonic filters on the input side, DC reactors or braking resistors for the DC link and chokes, dv/dt filters, sine filters or current transformers for the output side.
These are used in order to counteract interfering phenomena such as EMC problems, harmonic ripple, voltage spikes, short circuit currents and interference currents, and to meet the demands of the current EMC and power quality directives for clean energy networks, without restricting efficient plant operation. In addition when a motor is started or slowed down, starting currents have to be attenuated and excess energy dissipated and brake resistors remain the most cost effective option.