Abstract: An electric energy conversion apparatus comprising a.d.c. - a.c. conversion unit with a first solid state controllable power switch arrangement and a second solid state controllable auxiliary switch arrangement. Said first and second switch arrangements have their respective outputs connected to the respective ends of a primary winding of a transformer for providing at its secondary winding an a.c. voltage derived by the recurrent on-off switching action of said first power switch arrangement from an input d.c. The switching action performed by said first power switch arrangement is controlled by a control circuit arrangement in such a manner that said first switch arrangement is always switched into its non-conductive state prior to saturation of the core material of said transformer, and is switched into its conductive state directly following the switching action causing said second switch arrangement to become non-conductive. With said d.c.-a.c.

Abstract: A starting circuit for an inverter includes, at least, a control winding provided in connection with a saturable magnetic core of an input transformer of the inverter, a transistor and a capacitor. When a DC voltage source is activated, a discharge current of the capacitor flows through the collector-emitter circuit of the transistor and the control winding so as to start the switching operation of the inverter. A control circuit is provided for detecting a secondary voltage of the inverter so as to cut off the operation of the starting circuit after the inverter starts.

Abstract: A transistor inverter includes at least a pair of switching transistors, a transformer with primary and secondary windings, a DC voltage source with a pair of output terminals and a voltage reference terminal, and a rectifying circuit connected to the secondary winding of the transformer. A collector electrode of one of the switching transistors is insulated from a chassis by an insulation means comprising a first insulating layer, a conductive layer such as a heat sink and a second insulating layer. The conductive layer is electrically connected to the voltage reference terminal of the DC voltage source so as not to produce an undesirable radiation through the chassis.