Westek electronics has released a sine wave/EMC, three-phase, output filter for variable speed drives and suitable for long unshielded motor cables.
According to the company, the filter for variable speed drives solves three important problems for motors as loads for variable speed drives. These comprise of high dv/dt pulses, which if not smoothed by effective filtering, can damage motor and drive cable insulation by building up voltage stress through reflection of voltage pulses; common mode high frequency components due to high frequency switching IGBTs in the drive inverter stage, which without common mode filtering, flow through the motor frame to earth, damaging bearings in the process; and RF filtering thus preventing RF interference being radiated or conducted back to the input of the drive.
According to the manufacturer, the filters provide traditional L-C sine wave filtering, in combination with common-mode (Y) and symmetrical (X) mode EMC filtering and reduces protective earth current contributions by feeding common mode components back to the drive’s DC link.
The filters are suitable for operation for three-phase operation at line voltages to 500 volts, and current ratings are available from 4 to 16 amps.
Westek Electronics
03 9369 8802
info@westek.com.au
www.westek.com.au