Robert Boschgmbh

Volker Lurk

Frank Fischer

Nikolas Haberl

Michael Koerner

Christian Poddey

Tobias Stiefel

Stefan Koch

Gerald Roos

Wolfgang Krauth

Wolfgang Schwenk

Joerg Sutter

Patric Kahles

Claude Berling

Thomas Malich

Jan Van Goethem

Daniel Hofacker

The invention relates to an electric motor having a stator and a rotor. The electric motor also comprises a controller, wherein the controller is connected to the stator and/or rotor, and is designed for applying current to the stator and/or rotor for rotating the rotor. According to the invention, the controller comprises a pulse width modulator designed for controlling a power output of the electric motor, in order to generate a predetermined number of different current application patterns. The current application patterns each represent a power output of the electric motor, and preferably comprise a time sequence of current pulses, each having a current pulse duration. The controller is designed for applying current to the electric motor according to at least two different current application patterns for actuating the electric motor during a time interval of actuation, such that a power output of the electric motor in the time-based average of the time interval of actuation, in particular from the beginning to the end of the time interval, is different from the power outputs represented by the current application patterns in the time interval of actuation.

Electric motor having a pulse width modulator

The invention relates to a method for detecting blocking or sluggishness (M, M) of a DC motor (). The method comprises the following steps: applying a voltage pulse (U=O) to the DC motor (); monitoring a motor current (I) flowing through the DC motor (); detecting a maximum value of the motor current (I) following the application of the voltage pulse; checking whether a change in the motor current (I) after reaching the maximum value exceeds a specific amount; signalling the blocking or the sluggishness (M, M) of the DC motor () if the change in the motor current (I) after reaching the maximum value exceeds the specific amount.

Method and device for detecting blocking or sluggishness of a DC motor

A fan system includes: two circuit breakers, a control module for controlling two circuit breakers, two electric motors to which their operating voltage Uis supplied via the circuit breakers, and at least one temperature sensor on a board on which the circuit breakers are located. The control module evaluates a signal Tfrom the temperature sensor, and sets the pulse duty factors TV, TVof pulsed control voltages at the circuit breakers, while taking into account this signal as well as a requested fan power, in such a way that no power loss Pexceeding a specified value occurs at any circuit breaker.

Fan system having improved availability and method for its operation

An electronically commutatable motor having field windings activatable in sequence with a commutation frequency via semiconductor output stages using control signals connectable and disconnectable from a direct voltage supply, the control signals being clocked using pulse width modulation. Noise generation from connection and disconnection of the current applied to field windings is minimized by flattening of the rising and/or falling edges of the current in the field windings. The pulse width ratio increases in the rising edges of the control signals from a low initial value to an operating value assigned to the setpoint as a function of a selected setpoint for the motor speed or output, and, in the falling edges of the control signals, the pulse width ratio starts from the existing operating value and is reduced to a lower final turn-off value as a function of the existing actual value of the speed or the output of the motor.

Method of controlling an electronically commutatable motor

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Offenburg, Germany

Volker Lurk