Robert Boschgmbh

Rupert Weber

Arnim Fiebig

Olaf Kunz

Alfred Punzet

Siegfried Melzer

Gabriele Pfeiffer

Reinhard Cohrs

Stefan Melzer

Ralph Kennel

Werner Meister

Ralf Dickhaut

Thomas Kost

Eberhard Hoefflin

Guenther Boesche

A device for sensing an alternating current includes a circuit board on whose surface is arranged a planar conductor path in which a current to be measured flows. Applied on the opposite surface of the conductor path is a planar coil in which the change in the current to be measured induces a voltage. The device is advantageously used in a converter having a direct-current voltage link circuit.

Planar coil device, method and system for sensing changing currents in a planar conductor path

A drive device regulates a servomotor to one of a predefined position, a predefined speed, and a predefined current setpoint value. A control module is connected upstream from the drive device. A non-volatile memory where motor-specific data is stored is arranged in the housing of the servomotor. The housing has a data output through which the motor-specific data can be read. The motor-specific data is transmitted over a data line over which the feedback signals delivered by a sensor associated with the motor are also transmitted.

Drive system using a servomotor with a memory

A safety device for a drive is includes a monitoring system which evaluates a value describing the operating state of the drive in order to ascertain whether an emergency operation should be started for the protection of the drive instead of normal operation. The monitoring system generates at least one first output signal for an actuating element that influences the power supply to the drive. In normal operation an a.c. signal is used as the output signal and in emergency operation a d.c. signal is used.

Safety device for a drive mechanism

For driving each power transistor of a three phase bridge rectifier for utilizing d.c. electric power for the control and energization of a motor, each individual power transistor is provided with an individual driver circuit supplied an individual power supply. Each power transistor in such a rectifier has a reverse voltage free wheeling diode connected between emitter and collector. Each individual driver circuit has its input control signal supplied through a galvanic isolation stage in the form of an optical coupler and the power supply has its input connection to a source of power galvanically isolated by a transformer, supplying a relatively high frequency for powering the rectifier of the driver power supply. The final driver stage utilizes Darlington transistor combinations of complementary types, one Darlington combination being supplied with negative voltage and the other being supplied with positive voltage, by the power supply rectifier. The intermediate neutral voltage of the rectifier is connected galvanically to the emitter of a power transistor and the output connection coming from the junction of the two Darlington combinations is connected to the base electrode of the power transistor. The collector of the power transistor is connected to the control logic state that controls the driver input, this connection being made through a diode (60) for preventing the power transistor from being turned on while the reverse relief diode of the power transistor is conducting. The control logic circuit has a first bistable circuit (35) for setting the on periods of the driver and power transistor and a second bistable circuit (51,53) for registering an error condition and responding thereto by preventing the setting of the first bistable circuit.

Driver circuit for high-voltage power transistors providing protection

Growing community of inventors

Schneeberg, Germany

Rupert Weber