In an inverter with a plurality of connection groups, each of which includes positive and negative points of connection for connection to a feeding direct current voltage source and an alternating current terminal, controllable main rectifiers are connected between the positive point of connection and the alternating current terminal and between the alternating current terminal and the negative point of connection, with a commutating capacitor having one terminal connected to the alternating current terminal. There are a second positive and a second negative point of connection connected to a commutating direct voltage source, with controllable commutating rectifiers connected between the second positive point of connection and the second terminal of the commutating capacitor and between the second terminal of the capacitor and the second negative point of connection. Two pairs of windings are provided which are magnetically coupled to each other. One pair of windings has a winding connected between the first rectifier and the alternating current terminal and the second winding in series with the first commutating rectifier. The second pair of windings has one winding connected between the alternating current terminal and the second main rectifier and the second in series with the second commutating rectifier. A feedback valve has its anode connected to a point between the second main rectifier and the first winding of the second pair and its cathode connected to the first positive point of connection; and a second feedback valve has its anode connected to the first negative point of connection and its cathode to a point between the first main rectifier and the first winding of the first pair of windings.
The disclosure relates to an inverter comprising at least two controllable load thyristors which connect a load alternately with the poles of a feed d.c. voltage source. There is connected in parallel with each load thyristor one diode each which is a component of a commutation installation. The commutation installation manifests an LC-series oscillatory circuit dimensioned for a specified load current, and, manifests, for each load thyristor a controllable commutation thyristor which forms a closed circuit with the LC-series oscillatory circuit and its diode. The LC-series oscillatory circuit is connected to an auxiliary d.c. voltage source of a constant voltage via a reloading circuit.
