Description: The presence of capacitors in electric power supply networks with nonlinear loads can provoke a occurrence of resonance phenomenon and as a consequence a current increase and capacitors overheating.
In order to avoid resonance modes occurrence it is necessary to use the banks presenting an in-series resonance contour formed by a throttle which is switched on in-series with the capacitors. Such banks are called mismatched filters of higher harmonics.
The purpose of such connection is to reduce a network resonance frequency up to the value below the lowest higher harmonic. Throttle power is expressed in a percentage from the capacitor's power. Most frequently the throttles of 5.67%, 7% and 14% are used. Each value of the throttle power has its own resonance frequency. For instance, for 7% mismatching a resonance frequency is 189 Hz. It means that for all harmonics the frequency of which lies above 189 Hz, a network is an inductive resistance and for them the occurrence of resonance mode is unlikely. Therefore there is a solution of the problem for expensive equipment repairing which failed in the result of higher harmonic currents impact.
For automatic reactive power compensation of consumers' loads in general-purpose networks with voltage of 0.4 kV and 50 Hz when using the electrical load with nonlinear volt-ampere characteristic, where the harmonics are generated.
|Type designation||Quantity and power of steps||Overall dimensions, mm||Weight, kg, not more||Normative document|
|150(150,165)||СТ АО 921240000477-
In banks designation: the first number – numeral designation of resonance frequency (1-210 Hz for detuning 5,67 %; 2-189 Hz for detuning 7%; 3-135 Гц for detuning 14%);
second - rated voltage in kV;
third - rated power in kVAr;
fourth - power of control step.
Banks are completed with KPC capacitors and protective throttles for higher harmonic filtration.
Banks have a protection degree IP21.