Each bi-directional switch element may include a diode bridge (8) or (10) and directionally limited switches such as semiconductor switches.

Current is supplied to the diode bridge through a supply diode (52) and drained from the bridge through a drain diode (54), for controlling the switching of the bridge.

The half- controlled bridge includes a first switch, a second switch, a first diode and a second diode.

The rectifying circuit may take the form of a diode bridge network that includes four diode branches.

The circuit protection component may include a steering diode bridge and a crowbar device electrically connected to the steering diode bridge.

A connecting point of the sub diode bridge consisting of an upper sub diode and a lower sub diode connected in series is connected to a connecting point of the half bridge through the common compensating power source.

The rectifier bridges (11-14) may comprise first diode elements.

The first clamping diode (D1) and the second clamping diode (D2) are connected in series to form a bridge arm.

The OR connection is either a diode OR-qate or a bridge rectifier.

Preferably, the status indicator circuit includes a light-emitting diode in a rectifier bridge.

A diode bridge (20) is connected between the tip and ring signals.

A bridge diode, also called a rectifier, consists of four diodes.

The compensating leg consists of a common compensating power source, and a sub diode bridge connected to the half bridge in parallel.

The alternating current outputs from the thyristor bridge (7) are connected through the switching condensors (15) to the corresponding outputs of the diode bridge (14).

The bridge includes a diode coupled to the switching element such that the diode and the switching element are coupled between positive and negative rails of the inverter.