Abstract: The invention relates to a variable speed multi-phase motor powered via a converter, which reduces the control expenditure by dividing the stator winding into a number of partial coils corresponding to the phase number of the motor, arranged in equal grooves. A phase strand of each partial winding is connected to the one pole via a controllable semiconductor switching element, and the other phase strands are connected to the other pole of the direct current intermediate circuit of the converter in series to the one phase strand. Furthermore, a phase strand of each partial winding belonging to the other phase is connected to the corresponding pole of the direct current intermediate circuit via the controllable semiconductor switching element.

Abstract: A substantial reduction in required startup current is obtained in a drive arrangement with a three phase motor in that the stator winding of the motor comprises more than two winding legs per phase, all the winding legs of one phase being arranged in identical slots. During running up to speed of the motor, the more than two winding legs of each phase are wired symmetrically and are connected to the network in such a way that the magnetic fields produced by at least two winding legs per phase cancel each other out and only the remaining winding legs produce a rotating field.

Abstract: A circuit arrangement in which an a.c. load is connected in series with a capacitor unit suitable for a.c. connection. In such a circuit arrangement, the use of capacitors suitable for d.c. operation is made possible by the fact the capacitor unit is made up of two polar capacitors which are connected in series with the load in such a way that the capacitors are interconnected with matching poles, either directly or by way of the load with matching poles, as well as by the fact that a rectifier diode is connected to each capacitor, with the cathode of the rectifier diode being connected to the positive pole of the respective capacitor and the anode being connected to the negative pole of the respective capacitor.

Abstract: A circuit arrangement is disclosed in which a capacitive unit suitable for a.c. operation is connected in series with an a.c. load. An extension of the life of the capacitors can be achieved by having the capacitor unit consist of two capacitors connected in series either on the same side of the consumer or on opposite sides of the consumer, and that a separate rectifier diode is connected in parallel with each capacitor. Both rectifier diodes are connected with its forward direction opposite with relation to each other. This prevents reverse polarity voltage and charge, as well as reduces the duty cycle by fifty percent, thereby polarizing electrolytic capacitor life.

Abstract: A circuit for starting three-phase motors having a pole pair number p=2 and an uneven slot number q (slots per pole and phase) which is larger than 1 has a motor winding which is divided into two sections which can be switched on successively. To avoid a unilateral magnetic pull on the rotor during start up, the winding section to be switched on first includes more than one-half of the coils employed in each phase. These coils are tied together to form at least two identical parallel branches which are spatially shifted 360.degree. per pole. The balance of the coils, which form the winding section to be switched on later, are tied together to form at least one further parallel branch, and this branch (or branches) has the same number of turns as each of the parallel branches of the winding section which is to be switched on first.