The TPQDR3914 three phase dv/dt reactor from EMC solutions provider, EMIS, is a specially designed inductor installed at the output of a Variable Frequency Drive (VFD) or inverter to limit the rate of voltage rise (dv/dt) generated by PWM switching, reducing voltage stress and protecting motor insulation.
Modern VFDs use fast IGBTs that can create high dv/dt, voltage reflections (especially with long motor cables), increased bearing currents and EMI. Installation of a dv/dt reactor helps prevent premature motor failure, nuisance power tripping and mitigates EMI.
Designed for 0.8% impedance the reactor provides effective protection while causing a very low voltage drop and minimal power loss. The TPQDR3914 will operate reliably with modern high-frequency PWM drives, with current ratings from 4 A to 500 A. It reduces motor insulation stress, bearing currents, and the risk of premature motor failure while minimising reflected wave effects in long motor cables.
Among the other typical applications are pumps, fans and blowers, compressors, conveyors, HVAC, and more.
