Lenze Drives Gmbh

Lenze Automation Gmbh

Lenze Se

Heiko Stichweh

Volker Grabs

Torben Jonsky

Dirk Duesterberg

Holger Borcherding

Matthias Thesseling

Thorsten Hohnsbein

Albert Einhaus

Gennadi Boehm

Matthias Wisgickl

Felix Klute

Dirk DÜSTERBERG

A method for determining a rotational angle position of a rotor of a multiphase electrical machine, includes the steps of: generating phase voltages for the multiphase electrical machine by pulse width modulation in accordance with a drive voltage vector circulating in a stator-fixed coordinate system. During a determination time interval: a) generating a test voltage vector, vectorially adding the test voltage vector and the actual drive voltage vector to form a sum vector, outputting the sum vector, and measuring a resulting change of a current vector formed from phase currents; b) repeating step a) for a changed rotational angle position and/or a changed value of the drive voltage vector and for a changed test voltage vector a number n of times so that a total of n+I different test voltage vectors and sum vectors are generated and n+I resulting changes of the current vector are measured; and c) estimating the rotational angle position of the rotor in accordance with the total of n+I measured changes of the current vector.

Method for determining a rotational angle position of a rotor of a multiphase electrical machine, and frequency converter

A method for determining current-dependent and/or rotational angle position-dependent characteristic variables of an electrical machine by setting a rotational angle position of blocking a rotor, forming a series current desired value using a series current desired value alternating signal which changes periodically and/or forming a parallel current desired value using a parallel current desired value alternating signal which changes periodically, regulating a series current using the series current desired value and/or a parallel current using the parallel current desired value, measuring phase currents of the electrical machine and determining an established series current and/or an established parallel current, producing series setting voltage coefficients and series current coefficients and/or parallel setting voltage coefficients and parallel current coefficients using a discrete Fourier transform algorithm, and calculating characteristic variables on the basis of series setting voltage coefficients and series current coefficients and/or parallel setting voltage coefficients and parallel current coefficients.

Method for determining current-dependent and/or rotational angle position-dependent characteristic variables of an electrical machine, and frequency converter

A Vernier external rotor machine for direct drive of a load is provided. The Vernier external rotor machine includes an external rotor configured to mechanically directly drive to a load.

Vernier external rotor machine and motor system

A drive system has an electric motor, wherein the electric motor includes a first three-phase stator winding system and a second three-phase stator winding system. The first and the second stator winding system are arranged on the stator in a manner rotated through an electrical phase angle in relation to one another. The drive system includes a frequency converter, wherein the frequency converter has a first bridge circuit arrangement which is designed to generate voltages for the first winding system and a second bridge circuit arrangement which is designed to generate voltages for the second winding system. The first bridge circuit arrangement and the second bridge circuit arrangement are connected in series. A control device is designed to actuate the first bridge circuit arrangement and the second bridge circuit arrangement.

Drive system

A method is provided for generating a digital signal from an analog signal generated using a frequency converter on the basis of pulse width modulation with a variable period duration, values of the digital signal corresponding to an average value of the analog signal over an associated period duration of the pulse width modulation. The method includes the acts of: generating a bit stream on the basis of the analog signal using a sigma-delta modulator, the bit stream being generated with a constant modulator clock; generating temporally successive digital samples during an associated period duration by filtering the bit stream using a number of digital filters, intervals of time between the temporally successive digital samples being multiples of the modulator clock, the digital filters being started with a time delay with respect to one another in the intervals of time of the multiples of the modulator clock, and a respective digital filter outputting an associated digital sample, and forming an average value of the digital samples generated during the associated period duration, the average value forming the value of the digital signal (DS) for the associated period duration.

Method and device for producing a digital signal

The invention relates to a method for the open-loop or closed-loop control of an asynchronous machine with or without speed feedback, the asynchronous motor being controlled by a control device (converter or servo converter). First of all, a voltage vector rotating at a rotary field frequency is specified and impressed, both the rotary field frequency and the voltage vector being determined by an open-loop or closed-loop control based on a voltage-frequency characteristic curve configured in any manner and the voltage vector being adapted by a cos &#x3c6; closed-loop control. Desired values of cos &#x3c6; are calculated using rating plate data and equivalent circuit diagram data for an optimum-loss or loss-optimized operation of the asynchronous machine for the calculation of cos &#x3c6;, which results in optimized-loss operation. A value for cos &#x3c6;is then determined using the impressed voltage vector and a current vector or using the real power and apparent power. Thereafter, the difference is calculated between cos &#x3c6;and cos &#x3c6;and a cos &#x3c6; closed-loop control is fed with this input difference. A control value of the controller for cos &#x3c6; is calculated and restricted and the voltage vector is adapted by the control value of the cos &#x3c6; closed-loop control.

Method for controlling an asynchronous machine having a converter in a manner that is optimal for (copper) loss

Exemplary embodiments provide a method for connection or application of a converter to a rotating asynchronous machine which is operated without an encoder, without a high current and without a torque surge. The method provides a control unit, using an inverter or converter, for feeding the asynchronous machine which rotates at a mechanical rotary speed. The asynchronous machine is regulated by the control unit. A stator current vector is ascertained from measured currents of the stator windings of the asynchronous machine and a rotating stator voltage vector. Calculation is effected in respect of a stator flux change vector from the stator current vector, the stator voltage vector and a stator resistance in accordance with a motor model. An angle difference between the stator current vector and the stator flux change vector is calculated. That angle difference is regulated to a reference value of 90&#xb0; or &#x2212;90&#xb0;, wherein an output signal of the regulator corresponds to a rotary field frequency, to be impressed, of the voltage vector of the stator. Regulation is effected in respect of an amplitude of the stator voltage vector by way of a current regulator to which the difference of a current reference value and a parameter corresponding to the amplitude of the stator current is made available at the input as a regulating difference.

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Springe, Germany

Heiko Stichweh