IEC TS 60110: Induction Heating Capacitors — Specialized Components for High-Frequency High-Current

Induction Heating Capacitors — Specialized Capacitors Operating Under High Frequency, High Current

IEC TS 60110-2:2000 specifies power capacitors for induction heating installations. These capacitors operate at medium frequency (50 Hz–50 kHz) and high current (hundreds to thousands of amps) — dielectric loss and internal temperature rise dominate selection.

Key differences from power-frequency capacitors: (1) Dielectric loss increases with frequency — polypropylene film tan δ at 1 kHz can be 2–3× the 50 Hz value, dramatically increasing heat generation. (2) Internal inductance — at high frequency, internal lead inductance and non-uniform plate current distribution make ESL a critical resonant circuit design parameter. (3) Cooling requirements — induction heating capacitors often require water cooling because natural convection cannot dissipate dielectric loss heat.

TN Lab — High-frequency capacitors are not the same as power-frequency capacitors. Each tenfold frequency increase completely shifts the weighting of loss mechanisms.