A method for phase-voltage based motor period measurement includes generating a commanded phase voltage and applying the commanded phase voltage to a first phase voltage input of an electric motor, a second phase voltage input of the electric motor, and a third phase voltage input of the electric motor, measuring a first period of a phase voltage associated with the first phase voltage input and the second phase voltage input and comparing the measured first period to a frequency of the commanded phase voltage, and, in response to a determination that the measured first period of the phase voltage associated with the first phase voltage input and the second phase voltage input is outside of a range of the frequency associated with the commanded phase voltage, identifying a fault associated with the first integrated circuit or signal path.

A method for phase-voltage based motor period measurement includes generating a commanded phase voltage and applying the commanded phase voltage to a first phase voltage input of an electric motor, a second phase voltage input of the electric motor, and a third phase voltage input of the electric motor, measuring a first period of a phase voltage associated with the first phase voltage input and the second phase voltage input and comparing the measured first period to a frequency of the commanded phase voltage, and, in response to a determination that the measured first period of the phase voltage associated with the first phase voltage input and the second phase voltage input is outside of a range of the frequency associated with the commanded phase voltage, identifying a fault associated with the first integrated circuit or signal path.

Systems and methods for position determination in an electric machine are provided. Aspects include a DC power source connected to an inverter circuit, an electric motor comprising a rotor and a stator, wherein an output of the inverter circuit is connected to a plurality phase of windings, and a controller configured to operate the electric motor and the inverter circuit, wherein the controller is further configured to determine one or more inactive phase windings from the plurality of phase windings, supply a voltage to the inactive phase windings, receive, from a current sensor connected to the electric motor, a current for each inactive phase winding of the inactive phase windings, determine an inductance for each inactive phase winding of the inactive phase winding based on the current, and determine a position of the rotor in the electric motor based on the inductance for each inactive phase winding.

Systems and methods for position determination in an electric machine are provided. Aspects include a DC power source connected to an inverter circuit, an electric motor comprising a rotor and a stator, wherein an output of the inverter circuit is connected to a plurality phase of windings, and a controller configured to operate the electric motor and the inverter circuit, wherein the controller is further configured to determine one or more inactive phase windings from the plurality of phase windings, supply a voltage to the inactive phase windings, receive, from a current sensor connected to the electric motor, a current for each inactive phase winding of the inactive phase windings, determine an inductance for each inactive phase winding of the inactive phase winding based on the current, and determine a position of the rotor in the electric motor based on the inductance for each inactive phase winding.

According to some embodiments, method for controlling a motor comprises generating a drive signal for the motor, the drive signal comprising a demand flux generating voltage parameter. A feedback torque generating current parameter and a feedback flux generating current parameter are determined based on a three-phase motor current measurement. A feedback flux generating voltage parameter is determined based on the feedback torque generating current parameter and the feedback flux generating current parameter. An estimated motor position and an estimated motor speed are determined based on the feedback flux generating voltage parameter and the demand flux generating voltage parameter. The drive signal is generated based on the estimated motor position and the estimated motor speed.

According to some embodiments, method for controlling a motor comprises generating a drive signal for the motor, the drive signal comprising a demand flux generating voltage parameter. A feedback torque generating current parameter and a feedback flux generating current parameter are determined based on a three-phase motor current measurement. A feedback flux generating voltage parameter is determined based on the feedback torque generating current parameter and the feedback flux generating current parameter. An estimated motor position and an estimated motor speed are determined based on the feedback flux generating voltage parameter and the demand flux generating voltage parameter. The drive signal is generated based on the estimated motor position and the estimated motor speed.

The invention relates to a method for calibrating the control of an electrical machine, comprising the steps of: applying at least one electrical test signal having a specified direction in a d-q coordinate system to the electrical machine; measuring the change in the rotor angle of a rotor of the electrical machine according to the applied at least one electrical test signal; and calibrating the control of the electrical machine, the control being carried out using the d-q coordinate system, and the orientation of the d-q coordinate system being determined on the basis of the measured change in the rotor angle of the rotor of the electrical machine.

Provided is a method for determining the rotational position of a rotor in a permanent magnet synchronous machine, wherein the stator includes windings for a first, second and third phase, including the steps: applying a first voltage pulse to the first phase, determining respective first measures for the current induced by the first voltage pulse in the second and third phase, selecting a first selected phase depending on the first measures for the current, wherein the first selected phase is either the second or the third phase, applying a second voltage pulse to the first selected phase, determining respective second measures for the current induced by the second voltage pulse in the phases of the stator that are not the first selected phase, and determining the rotational position of the rotor depending on the second measures of the current.

Provided is a method for determining the rotational position of a rotor in a permanent magnet synchronous machine, wherein the stator includes windings for a first, second and third phase, including the steps: applying a first voltage pulse to the first phase, determining respective first measures for the current induced by the first voltage pulse in the second and third phase, selecting a first selected phase depending on the first measures for the current, wherein the first selected phase is either the second or the third phase, applying a second voltage pulse to the first selected phase, determining respective second measures for the current induced by the second voltage pulse in the phases of the stator that are not the first selected phase, and determining the rotational position of the rotor depending on the second measures of the current.

A method ascertains current-dependent inductances of a polyphase electrical machine. The method generates phase voltages for the polyphase electrical machine by means of a pulse width modulation such that currents of predefined current level flow through stator windings of the electrical machine. During a number of cycles of the pulse width modulation, the method generates a voltage pulse such that a change of current is brought about in a torque-forming axis of the polyphase electrical machine and/or in a field-forming axis of the polyphase electrical machine. The method measures the change of current, and ascertains the current-dependent inductances on the basis of the change of current.