Definition of filter capacitor

Definition

1.1 band pass and high pass filter capacitors

A capacitor (or capacitor bank) that is connected with other accessories, such as reactors and resistors, to provide a low impedance channel for one or more harmonics [1]

1.2 rated voltage (UN)

The arithmetic sum of the root mean square value of the fundamental voltage, or the voltage calculated from the reactance of the capacitor under the rated capacity and rated frequency, whichever is greater.

1.3 rated capacity (QN)

The arithmetic sum of the capacity generated by the fundamental wave and the capacity generated by the harmonic wave.

1.4 rated current (in)

The square root of the sum of the square values of the fundamental rated current and the harmonic rated current.

Quality requirements and tests

2.1 Capacitance Deviation

Symmetrical capacitance deviation is recommended.

2.2 voltage test between outgoing terminals

Ut=2.15U1+1.5UH

2.3 thermal stability test

For filter capacitor, if 1.44qn is lower than the capacity determined by 1.1un at the fundamental frequency, the latter test voltage overload shall be used in the thermal stability test, which shall be marked by the agreement between the supplier and the demander, and the tuned frequency meter shall be installed behind the rated frequency, and the reactor connected in series with the filter capacitor shall cause the rise of the fundamental voltage on the capacitor terminal.