🧲 เครื่องคำนวณขนาดรีแอกเตอร์

A series Reactor is connected in series with a capacitor bank to detune Harmonics (typically 6% or 7% impedance) and protect capacitors from inrush. A shunt reactor is connected to ground or across the line to absorb capacitive reactive power and limit overvoltage on long lines. The calculator prices both (CKSG series, BKSC shunt).

A 7% reactor shifts the resonant frequency below the 5th harmonic (250 Hz) to avoid resonance with the 5th and higher harmonics; 6% is used where only the 5th is present. 7% is the safer default for most industrial networks. The calculator sizes the reactor kVAR from the capacitor bank kVAR.

The reactor kVAR is the detuning percentage of the capacitor kVAR. For a 100 kVAR bank at 7%, the reactor is 7 kVAR. The reactor must also carry the capacitor current plus harmonics, so it is rated for the bank current at the detuned frequency. The calculator computes the reactor rating automatically.

Without a reactor, a capacitor bank can form a parallel resonance with the Transformer inductance near a harmonic frequency, amplifying harmonic current and overheating the bank. A 6-7% reactor detunes the circuit below the dominant harmonic. The calculator flags the detuning recommendation and prices the reactor.

Series and shunt reactors follow IEC 60076-6 (reactors) and GB/T 1094.6, with rated voltage, kvar and impedance as key parameters. Temperature Rise and insulation class follow the same transformer standards. The calculator's BOM cites the applicable standard for the selected reactor.