Robert Bosch

Harald Witzig

Gerhard Knecht

Thomas Heese

Stefan Beyer

In a brushless direct-current drive with a synchronous motor ( ), which has a stator ( ) that supports a multi-phase stator winding ( ) and a rotor ( ) equipped with permanent magnet poles ( ), and with a switch unit ( ), which precedes the stator winding ( ), for commutating the stator winding ( ), in order to produce a fail-silent behavior, a field excitation winding ( ) is disposed in the rotor ( ), which winding can be supplied with current in the event of a malfunction so that it generates a magnetic flux oriented in the opposite direction from the magnetic flux of the permanent magnet poles ( ).

Brushless DC drive

A brushless d.c. drive including a synchronous motor, including a multiphase armature winding, a switching device controlled by an electronic controller and connected upstream from the armature winding for commutation of the armature winding, and a device for generating a fail-silent response with simple circuitry measures and without any external components, and which includes a separating apparatus, arrangement or structure in the armature winding to respond in the event of a fault and separate the connections between the winding phases, including at the neutral point.

Fail-safe mechanism for dc-drive

An electronically commutated polyphase synchronous machine has a rotor ( ) and a stator ( ) which carries a stator winding ( ); the stator has a switching device ( ) having a plurality of semi-conductor switches (T -T ) which are assigned to the individual winding phases ( ) of the stator winding ( ); the switching device is used for connecting the stator winding ( ) to a direct voltage system ( ), and a commutation device ( ) for sequential triggering of the semiconductor switches (T -T ) using switching signals which are derived from rotor angular position signals. For sensorless detection of the angular position of the rotor, auxiliary windings ( ) are situated in the stator ( ), which are each inductively coupled to a winding phase ( ), and the rotor angular position signals are derived from voltages induced in the auxiliary windings ( ).

Electronically commutated multi-phase synchronous machine

A method for driving at least one inductive load using pulse width modulated control signals, via a PWM control unit, the control pulses of the PWM control signals connecting the load to and disconnecting it from a d.c. supply voltage via a semiconductor output stage. To prevent the formation of an a.c. voltage occurring on the d.c. supply voltage in the case of pulse-wise loading of the same by the PWM control signal, the PWM control unit is assignable a supplementary device including a storage capacitor and/or storage inductor having a semiconductor switch, and the semiconductor switch is controllable by the PWM control unit switch on one charging current circuit powered by the d.c. supply voltage for the storage capacitor and/or the storage inductor.

Growing community of inventors

Cheongwon-gun, South Korea

Harald Witzig