Abb Schweiz Ag

Abb Research Ltd.

Luca Peretti

Omer Ikram Ul Haq

Heinz Lendenmann

Hector Zelaya De La Parra

Rahul Kanchan

Subrat Sahoo

Panagiotis Kakosimos

Mehanathan Pathmanathan

Minos Beniakar

Jahirul Islam

Paul Sandulescu

Giovanni Zanuso

Tobias Rogg

Dmitry Svechkarenko

A method for continuous operation of a rotating machine, the method is performed in a rotating machine having an inner stator and an outer stator. The method includes setting a rotating machine reference operational value for the whole rotating machine, obtaining operational parameters for the inner stator and for the outer stator, wherein the operational parameters include magnetic cross-coupling between the inner and outer stators, determining an inner stator reference operational value for the inner stator and an outer stator reference operational value for the outer stator based on the set rotating machine reference operational value for the whole rotating machine and the obtained operational parameters, and driving the rotating machine based on the determined inner stator reference operational value for the inner stator and on the determined outer stator reference operational value for the outer stator, wherein the determined inner stator reference operational value for the inner stator differs from the determined outer stator reference operational value for the outer stator.

Control and drive of a rotating machine with an inner and an outer stator

A double-stator PM machine having: an outer stator generating an outer electromagnetic field dependent on an outer three-phase supply current; an inner stator generating an inner electromagnetic field dependent on an inner three-phase supply current; a PM rotor rotated by the outer and inner electromagnetic fields between the outer and inner stators; and a control arrangement controlling the outer and inner supply currents. There is an electrical connection between neutral points of the outer and inner stators. The control arrangement is configured for controlling the outer and inner supply currents such that there is a relative angle shift of 30&#xb0; between the outer and inner supply currents and such that a third order current harmonic component is circulated between the outer and inner stators.

Double-stator PM machine with 3rd order current harmonic injection

A method of controlling an electrical machine, wherein the method includes: a) injecting a first voltage waveform (u) with a first fundamental frequency into the electrical machine in a first axis of a rotor reference frame, combined with a voltage signal for controlling the electrical machine, b) determining a second axis current component (i) of a second axis of the rotor reference frame, having the first fundamental frequency, generated in response to the injection of the first voltage waveform (u), c) controlling based on the second axis current component (i) a second axis voltage component (u) of the second axis, having the first fundamental frequency, to obtain an adjusted second axis voltage component for controlling the second axis current component (i) towards zero, d) feeding back the adjusted second axis voltage component to combine the adjusted second axis voltage component with the voltage signal and the injected first voltage waveform (u), and repeating steps b)-d) until the second axis current component is smaller than a threshold value (i), e) determining a differential cross-coupling parameter of the electrical machine based on the second axis voltage component (u) and a first axis current component (i) having the first fundamental frequency, when the second axis current component is smaller than the threshold value (i), and g) controlling the electrical machine based on the differential cross-coupling parameter.

Method of controlling an electrical machine

A method of detecting a permanent magnet rotor of a synchronous machine, includes: injecting a voltage waveform to the stator windings of the synchronous machine, measuring two phase currents in the stator winding, transforming the two phase currents to a rotor reference frame to obtain a current waveform, sampling the current waveform to obtain positive and negative portion values, constructing first and second periodic waveforms by using the sampled positive and negative portion values, performing a frequency analysis of a first and second spectrums of the periodic waveforms, and determining whether a permanent magnet is present in the synchronous machine based on the spectrums.

Method and device for detecting the presence of a permanent magnet of a rotor of a synchronous machine

A method for determining an undesired condition in an electrical drive system including an electrical machine and an electrical drive, wherein the method includes a) obtaining a measured signal of an electrical or mechanical parameter, b) obtaining a frequency spectrum of the measured signal, that contains a measured frequency component, c) determining whether the measured frequency component is within a predetermined distance from a trend line, which trend line is associated with only one specific frequency component of the electrical or mechanical parameter present during a specific undesired condition, d) on the condition that the measured frequency component is within the predetermined distance from the trend line increasing a counter associated with the trend line, e) repeating steps a) to d), wherein in case the counter reaches a predetermined number determining that the electrical drive system is subjected to the undesired condition associated with the trend line.

Method and controller for determining an undesired condition in an electrical drive system

A self-commissioning method for estimating differential inductances in an electric machine, such as e.g. a synchronous reluctance machine or interior permanent magnet machine, with cross-magnetization effects is provided. The electric machine is driven with PWM voltages to explore current plurality of operating points of the currents in the electric machine while keeping the electric machine at standstill or quasi-standstill. At each operating point PWM switching voltage transients are used as a small-signal excitation. Currents of the electric machine are measured by means of oversampling, which permit the reconstruction of the waveforms including the current ripple within a PWM period caused by the PWM switching transients. Finally, the differential inductances at each operating point are determined based on the determined direct and quadrature current waveforms and voltages.

Method and system for estimating differential inductances in an electric machine

A method for finding an operating point of an electric motor which includes the steps of generating a perturbation signal, combining the perturbation signal with a current magnitude related to a drive system of the motor or combining the perturbation signal with a power magnitude related to the motor, yielding a combined signal, and sending, based on the combined signal, a flux adjustment signal to adjust a flux of the motor. An apparatus for finding an operating point of an electric motor comprising is also presented.

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Järfälla, Sweden

Luca Peretti