A method for estimating amplitude of a periodic component in a measured signal, wherein the method comprises the following operations: performing a delta-sigma modulation on a received analog signal to obtain a digital signal; applying at least one filter to the digital signal and to a first periodic signal to estimate a first amplitude signal representative of the first periodic signal in the digital signal.

The method further comprises a control operation of: adapting a control law of an external entity based on at least the first amplitude signal; or calculating a monitoring value based on at least the first amplitude signal.

A method for determining a rotation variable of a rotatably mounted rotor of a mechanically commutated electric motor, having a motor current path formed between two brush elements of the electric motor, and leading via the commutator bars contacted by the brush elements, and via coil windings of the rotor electrically connected to said commutator bars, wherein an oscillating input signal is fed into the motor current path and the rotation variable is determined with the aid of a ripple of a resultant output signal, said ripple being due to the mechanical commutation of the motor current path.

In a sensorless control of a motor, due to the characteristic of a response frequency, an induced voltage, a magnetic pole position estimation gain, a current control gain, and a speed control gain are closely related. An object of the invention is to enable the induced voltage and the frequency characteristic of a magnetic pole position estimation system to be clearly designed and to theoretically and quantitatively design all of the control gains necessary for the sensorless control so as to solve a problem that a method of designing those parameters cannot be established and the parameters have to be adjusted in a try and error manner. A control device has an estimator estimating an estimation induced voltage and a phase error of a motor by applying an induced-voltage observer and a controller controlling the motor on the basis of the estimation induced voltage and the phase error.

In the present invention, in an electromagnetic device that uses a coil current, such as a motor, an initial value of a desired coil current waveform is inputted, a magnetic field analysis is performed for the electromagnetic device, a power supply voltage waveform which is derived from a magnetic vector potential acquired from the analysis is calculated, and a circuit coupled magnetic field analysis is performed by using a fundamental waveform component of the calculated power supply voltage waveform, thereby providing a power supply voltage waveform calculation method and a circuit coupled magnetic field analysis method for obtaining a steady solution more quickly than in the conventional technique.

The disclosure relates to a method for determining a rotor position of an electric rotating machine. The electric machine comprises at least one first, multi-phase subsystem and one second multi-phase subsystem, which each comprise a PWM-controlled inverter for feeding respective winding groups. The winding groups of the at least first and second subsystems are arranged substantially electrically offset from one another by 360. In the method, voltages predefined by a controller are altered by feeding high-frequency voltages in order to attain high-frequency current changes. The current changes are then detected in that a current curve of phase currents is ascertained for each subsystem by measuring at least one first phase current and one second phase current. The rotor position is then determined depending on the ascertained current curves and the fed high-frequency voltages. The disclosure additionally relates to an electric machine which is designed for carrying out the method.

A control device for controlling a rotary electric machine, the control device includes a current command unit, a voltage conversion device, a current conversion device, a signal demodulation device, an error compensation unit, an adding device and a position estimation device. The current command unit provides a d-axis current command and a q-axis current command. The current conversion device converts a current of the rotary electric machine to a synchronous reference coordinate current. The signal demodulation device computes a current variation of a high-frequency synchronous reference coordinate current. The error compensation device outputs a first correction value. The adding device adds the current variation of the high-frequency synchronous reference coordinate current and the first correction value to generate a second correction value. Based on the second correction value, the position estimation device adjusts a phase estimation value for the current conversion device and the voltage conversion device.

A control device includes an estimation module configured to repeatedly calculate an angle estimation value correlated with a magnetic pole position of a rotating electric machine, and a storage module configured to store the angle estimation value. The estimation module includes a response information calculation module configured to calculate response information indicating a current change resulting from a change in an output voltage to the rotating electric machine or a voltage change resulting from a change in an output current to the rotating electric machine, a coefficient calculation module configured to calculate an interference coefficient correlated with electromagnetic mutual interference between coordinate axes of an orthogonal coordinate system of the rotating electric machine based on a past angle estimation value stored in the storage module, and an angle calculation module configured to calculate an angle estimation value based on the response information and the interference coefficient.

The present invention discloses a method for determining a rotor angle of a rotor of an electric machine, having the steps of producing a torque-dependent test signal which depends on the torque of the electric machine and has a higher frequency than a supply signal for the electric machine, controlling the electric machine using the supply signal and the test signal which is superimposed on the supply signal, recording phase currents of the electric machine, and determining the rotor angle of the rotor of the electric machine on the basis of the effects of the test signal on the phase currents. The present invention also discloses an angle determination apparatus and a corresponding control apparatus.

A method of estimating an operating state of a drive system is presented. The drive system comprises an electric motor and a mechanical unit being moved by the electric motor. The method comprises a) operating the electric motor using electrical properties, b) determining movement properties regarding the movement of the mechanical unit using the electrical properties, repeating steps a) and b) for a number of times using changed electrical properties, and generating a distribution function. The distribution function allocates electrical properties to the resulting movement properties. The method also comprises estimating the operating state in response to the generated distribution function.

An actuating apparatus for a polyphase motor includes five phase terminals for connecting of in each case one phase of the polyphase motor, a high terminal for applying a supply voltage (U.sub.B), a low terminal for applying a reference potential of the supply voltage (U.sub.B), a control device, wherein the control device is adapted, in four of the five phase terminals, to impress a pulse-width-modulated voltage pattern by connecting the phase terminals to the high terminal or the low terminal so that in the first phase terminal, an evaluation signal which is dependent on the angle of rotation of the polyphase motor is produced, and wherein the control device is adapted to determine the angle of rotation and/or a commutation condition of the polyphase motor from the evaluation signal.