Bi-directionally controlled thyristors (BCT)
Thyristors are typically used as phase-controlled current valves for AC to DC conversion and vice versa, operating at low frequencies (most often around AC line frequency). In the conducting state, thyristors feature very low losses, making them attractive devices to efficiently control very high currents and energies.
All ABB Thyristors are press-pack devices. They are pressed with a relatively high force onto heat-sinks which also serve as electrical contacts to the thyristor terminals.