IREM offers specific solutions for the reduction of harmonics in 12-pulse rectifiers, improving efficiency and power quality. A recent project involved an industrial UPS in a nuclear power plant, where a passive harmonic filter was installed to reduce the harmonic content THDi to values below 3%.
Project Technical Specifications
The system features a mains voltage of 480V, an AC line current of 1000A and copper windings with insulation class H. The inductors and capacitors of the project were made according to seismic resistance criteria, with capacitors rated at 690V.
Why use a passive harmonic filter?
IREM passive harmonic filter offers multiple advantages: it reduces current harmonics and improves power factor, complying with IEEE519 and IEC61000-3-12 standards. In addition, it minimizes system losses due to harmonic distortion and maintains low operating temperatures with reduced power consumption. The modular design allows for custom construction, with separate components such as line choke L1, load choke L2 and trap choke L3, as well as capacitors C.
IREM solutions are ideal for high power industrial UPS and AC-DC conversion systems, including 6 and 12 pulse systems using SCR power electronics. Typical applications include the reduction of harmonics fed into the grid, the optimization of Power Quality and the management of critical issues related to power supply through generator sets.
Improved power factor and power quality
Thanks to these filters, it is possible to increase the power factor from 0.75 to 0.95, reduce losses in the LV distribution and improve the overall quality of the power supply. The adoption of the harmonic filter has also allowed the reduction of harmonics of order 11 and 13, as well as the elimination of harmonics of order 5 and 7, with a significant reduction in THD compared to 6-pulse rectifiers.
IREM Custom Solutions for Harmonic Filters
IREM is able to produce standard and customized filters with currents from 5A to 1500A, both for motor applications (AC-AC with VFD and AC-DC) and for specific loads such as rectifiers, PID controlled ovens with SCR, and other power electronics applications. The solutions are available in IP00 version for integration in customer cabinets or as retrofit applications in IP21 and IP54 versions for indoor or outdoor environments.