Harmonic filter resistors
Harmonic Filter Resistors are used to attenuate harmonic frequencies that would otherwise perturb the power grid. In any application where power semiconductor switches are used, such as in wind-turbine inverters, variable frequency drives or controlled rectifiers, harmonic voltages and currents are generated causing additional losses and interference with other electrical circuits. Harmonic Filter Resistors are used in combination with capacitors and inductors, their power dissipation depends on the sum of all attenuated harmonics.