🧲 Reactor Sizing Calculator
Size a series or shunt reactor from your capacitor bank kVAR and the impedance ratio, and get the reactor kVAR, model and reference FOB price.
⚙️ Capacitor Bank
📊 Result
For engineers adding detuned or shunt reactors to power-factor and harmonic-filter banks.
How it is calculated
· Reactor capacity: kVAR_reactor = kVAR_capacitor × impedance %.
· Standard impedance ratios: 6% / 7% (detuned), 12% / 14% (harmonic filtering).
· Price = base × voltage factor × impedance factor × connection factor.
Referenced standards
| Standard | Scope |
|---|---|
| IEC 60289 | Reactors — general requirements |
| GB/T 10229 | Chinese equivalent for reactors |
Worked example — 200 kVAR bank at 7% → 14 kVAR
1. Capacitor bank 200 kVAR, series impedance 7%.
2. Reactor kVAR = 200 × 7% = 14 kVAR.
3. Model CKSG-14/10 (series, 10 kV); reference price from the reactor price table.
FAQ
What is the difference between a series and shunt reactor?
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).
What detuning factor do I choose — 6% or 7%?
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.
How is a reactor kVAR rating related to the capacitor bank?
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.
Why do capacitor banks need reactors?
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.
What standard applies to power reactors?
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.
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Related tools
Reference estimates (FOB Qingdao, EXW) for preliminary design only — not a final quote. Confirm sizing against your project and local standards.
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