Schaltung und Verfahren für die Ansteuerung eines bürstenlosen Gleichstrommotors

摘要

The circuit proposed includes an oscillator (1) to generate a delta voltage in dependence on commutation pulses resulting from the position of the rotor of the d.c. motor, a sample-and-hold circuit (2) for sampling and retaining a hold voltage (Ul) from the varying delta voltage at the time of commutation, and an amplifier (4) to amplify the difference between the delta voltage and the hold voltage (Ul), the amplifier-output signal being fed to the final control stage. In addition, an adder (3) can be used to add a voltage (U Block) to the hold voltage (Ul) sampled and retained from the delta voltage, the difference between the delta voltage and the sum of the hold voltage (Ul) and block voltage (U Block) being amplified in the difference amplifier (4). The method is thus characterized in that, in the control signal, the gradient of the flanks is adjusted by varying the amplification of the difference amplifier (4) and/or the length of the blocks by adding a block voltage by means of an adder (3).