Sinac’s high-frequency systems offer parallel- and
serial-compensated converters. The parallel-compensated
high-frequency systems are based on the same
fast IGBT technology as the medium-frequency systems,
making it possible to run up to 200 kHz.
Sinac’s serial-compensated high-frequency systems
feature IGBT transistors and three-phase diode rectifiers.
The IGBT inverters are based on EFDInduction-patented switching pattern technology
that utilizes the IGBT transistors at high frequencies
without any extra stress. Solid-state technology
helps ensure maximum uptime and throughput.
Sinac multi-frequency systems use patented EFD
Induction technology to deliver two different
frequencies—one high and one low—to one coil at
the same time. This gives you the flexibility to treat a
wide range of components. The systems are serialcompensated
and feature rugged IGBT transistors
in full bridge circuits. The custom-designed coils
are connected directly to the inverter matching
All the system uses the same generator and heating unit (coil) perfectly adapted to our purpose. The induction coil is powered by a HF-generator operating at a frequency high enough to give the induced current a penetration depth smaller than 1/10 of a mm. The HF power is adjusted and continuously measured and automatically adjusted to provide equal heating independent of product size, coil size and steel grade. The coil with a flexible cable is mounted on a hydraulic servo unit. The servo centers the coil and moves with the billet for safety, equal heating of all faces and positions the coil automatically when changing billet size. The coil is released when hit to prevent serious damage.