DE102021133422A1 - Method for determining the angle of the rotor and/or the angular velocity of an electric motor, controller and motor vehicle - Google Patents

Abstract

A method for determining the angle of a rotor and/or the angular velocity of an electric motor comprises the following steps:- Obtaining a first rotor position signal (P1) from a first rotor position sensor (16) and a second rotor position signal (P2) from a second rotor position sensor (17). a controller (14), and- determining the angle (ϕ) of the rotor (20) and/or the angular velocity (ω) by means of a filter module (36) of the controller (14), wherein the filter module uses the first rotor position signal (P1) and the second rotor position signal (P2) processed together in each case as a complex angle function (K1, K2).

Description

The invention relates to a method for determining the angle of the rotor and/or the angular velocity of an electric motor, a controller and a motor vehicle.

The angle or the angular position of the rotor indicates the position of the rotor in the electric motor.

Electric motors are used in motor vehicles as a drive to convert electrical energy into propulsion. For this purpose, a rotating field is generated on the stator of the electric motor, so that the magnetic rotor of the electric motor rotates in the magnetic field of the stator. The speed and power of the motor depend on the speed of the rotor and thus on the magnetic field applied to the stator.

In order to ensure an efficient transfer of electrical energy into mechanical propulsion, a certain angle or phase offset between the applied magnetic field and the rotor is necessary. Therefore, a precise determination of the position of the rotor, ie a precise determination of the angle of the rotor, and a precise determination of the angular velocity of the electric motor is necessary.

For this purpose, it is known from the prior art to process the signals from a rotor position sensor using a complex trigonometric function and a filter. Such a method is shown, for example, in DE 10 2019 122 558 B4 .

However, in the known prior art, intrinsic errors in the rotor position sensor lead to inaccuracies in the determination of the angle and/or the angular velocity, as a result of which the efficiency of the transmission is reduced.

It is therefore the object of the invention to improve the method known from the prior art for determining the angle of the rotor and/or the angular velocity of the electric motor.

• - Erhalten eines ersten Rotorpositionssignals von einem ersten Rotorpositionssensor und eines zweiten Rotorpositionssignals von einem zweiten Rotorpositionssensor durch einen Regler, wobei das erste und das zweite Rotorpositionssignal jeweils einen Positionswert entlang einer ersten von zwei Achsen in der Rotationsebene des Rotors und einen zweiten Positionswert entlang der zweiten der beiden Achsen umfasst, wobei die Rotorpositionssignale mehrere Ordnungen enthalten, und
• - Ermitteln des Winkels des Rotors und/oder der Winkelgeschwindigkeit mittels eines Filtermoduls des Reglers, wobei das Filtermodul das erste Rotorpositionssignal und das zweite Rotorpositionssignal zusammen jeweils als eine komplexe Winkelfunktion verarbeitet.

The task is solved by a method for determining the angle of the rotor and/or the angular velocity of an electric motor. The electric motor has a rotor and a stator with at least one coil, in particular with three coils, and the method comprises the following steps:

• - obtaining a first rotor position signal from a first rotor position sensor and a second rotor position signal from a second rotor position sensor by a controller, the first and second rotor position signals each having a position value along a first of two axes in the plane of rotation of the rotor and a second position value along the second of the both axes, the rotor position signals containing multiple orders, and
• - Determining the angle of the rotor and/or the angular velocity by means of a filter module of the controller, the filter module processing the first rotor position signal and the second rotor position signal together, each as a complex angular function.

The invention is based on the finding that the rotor position signals from various rotational position sensors can be processed together in a controller as a complex angular function. The position values along both axes of each rotor position sensor, i.e. each rotor position signal, are processed in the controller as a complex angle function. In this way, redundant information is processed in the controller, so that the accuracy of the angle determination is improved. In addition, by using rotor position signals from different rotor position sensors, sensor-intrinsic errors of a single rotor position sensor are reduced and the method known from the prior art is improved in this way.

In other words, the rotor position sensors provide mutually redundant information. The combination of this data can then improve the accuracy of the determination of the angle and/or the angular velocity. This is also commonly referred to as data fusion of the sensor data from the various rotor position sensors.

Each rotor position sensor generally provides an analog rotor position signal that is sampled with a certain sample time. Accordingly, the rotor position signals received from the controller are discrete. The sampling time of each rotor position signal is predetermined, for example, by the corresponding rotor position sensor and/or the controller.

Since the sampling time of the rotor position sensor is very short compared to the period of rotation of the rotor, the rotor position signals are almost continuous. Thus, the rotor position signals can be described as a trigonometric series.

One aspect of the invention provides that the filter module determines a phase offset between the first and the second rotor position signal and takes it into account when determining the angle of the rotor and/or the angular velocity. In this way, the accuracy of the determination of the angle and/or the angular velocity is further improved.

The controller can use the rotor position signals to deduce the functional status of the two rotor position sensors. When a fault condition is detected in one of the rotor position sensors, the controller does not take the corresponding rotor position signal into account when evaluating the angle and/or the angular velocity. In this way, on the one hand, the accuracy of the determination of the angle can be increased (if both rotor position sensors are functioning properly) and, on the other hand, redundancy of the entire system is ensured. By excluding the rotor position signal from the non-functional rotor position sensor, the evaluation is not influenced by the faulty data. Erroneous data is therefore discarded without being taken into account during the evaluation, with sufficient data nevertheless being available to ensure an adequate evaluation due to the data fusion.

In one embodiment, the controller uses the phase offset to infer the functional states of the rotor position sensors. In practice, the phase shift has proven to be a reliable parameter for monitoring the functional status.

In this case, the regulator monitors in particular the phase offset as a function of time and, based on the course of the phase offset, can conclude which rotor position sensor is not working properly.

In general it is also conceivable that the controller receives additional information about the rotor position sensors.

In order to compensate for a so-called orthogonality error of a rotor position sensor, the filter module can determine the axis angle between the two axes of each rotor position signal and take the axis angles into account during the determination of the angle of the rotor and/or the angular velocity. In this way, the accuracy of the method is further improved.

The orthogonality error is understood to mean the error of a rotor position sensor in that the detection directions of the rotor position sensor are not orthogonal to one another, but are twisted relative to one another.

The axis angle can be determined as a deviation from 90°. In this way the processing of the axis angle in determining the angle of the rotor and/or angular velocity is simplified since the whole system is described relative to the ideal case using cosine and sine functions.

In other words, a phase shift is used between the cosine and sine components of the complex trigonometric function.

In one embodiment of the invention, the first rotor position signal and the second rotor position signal are pre-processed by means of a pre-processing module before they are fed to the filter module. The pre-processing module fits a complex trigonometric series to the first and second rotor position signals and passes the complex trigonometric series to the filter module as the respective rotor position signal. The pre-processing reduces the time for evaluating the angle of the rotor and/or the angular velocity.

• - Bestimmen von zumindest einem Stromkorrekturwert für die zumindest eine Spule durch den Regler anhand des ermittelten Winkels, und
• - Anpassen des Stromflusses durch die zumindest eine Spule anhand des zumindest einen Stromkorrekturwertes durch den Regler.

The electric motor can be controlled by the controller at least on the basis of the determined angle, in particular through the following steps:

• - Determination of at least one current correction value for the at least one coil by the controller based on the determined angle, and
• - Adaptation of the current flow through the at least one coil based on the at least one current correction value by the controller.

In this way, the electric motor is controlled directly by the determined angle, enabling fast and precise control.

The first rotor position signal and the second rotor position signal may each be provided by a magnetoresistive rotor position sensor. Magnetoresistive sensors are robust, small and very energy efficient.

The method according to the invention is not limited to magnetoresistive rotor position sensors. In general, any rotor position sensor that provides the projection of the rotational movement of the rotor along at least one axis is conceivable.

For example, one of the rotor position sensors can be a Hall sensor, an eddy current sensor, an optical incremental encoder, a resolver and/or a hardware demodulator.

und für den zweiten Rotorpositionssensor der Form $$\begin{array}{l}{K}_2\left(t\right)={\displaystyle \sum _i^{\infty }{A}_{c\mathrm{,2,}i}\left(t\right)\cdot \text{cos}\left(p_2\mathrm{ }{\mathrm{\varphi }}_2\mathrm{ }\left(t\right)+\Delta {\mathrm{\varphi }}_{\mathrm{2,}i}+{\mathrm{\varphi }}_{\mathrm{1,2}}\right)+{\text{O}}_{c\mathrm{,2}}\left(\text{t}\right)}+\\ j\cdot \left[A_{s\mathrm{,2,}i}\cdot \text{sin}\left(p_2{\mathrm{\varphi }}_i\left(t\right)++{\mathrm{\varphi }}_{\mathrm{1,2}}\right)+{\text{O}}_{s\mathrm{,2}}\left(\text{t}\right)\right]\end{array}$$

sein.The complex trigonometric function can be of the form for the first rotor position sensor $$\begin{array}{l}{K}_1\left(t\right)={\displaystyle \sum _i^{\infty }{A}_{c\mathrm{,1,}i}\left(t\right)\cdot \text{cos}\left({\mathrm{<figure-callout\; id="1"\; label="p"\; filenames="DE102021133422A1\_0056.png"\; state="\{\{state\}\}">p</figure-callout>}}_1{\mathrm{\varphi }}_i\left(t\right)+\Delta {\mathrm{<figure-callout\; id="1"\; label="\phi "\; filenames="DE102021133422A1\_0056.png"\; state="\{\{state\}\}">\varphi </figure-callout>}}_{\mathrm{1,}i}\right)+{\text{O}}_{c\mathrm{,1}}\left(\text{t}\right)}+\\ j\cdot \left[A_{s\mathrm{,1,}i}\cdot \text{sin}\left({\mathrm{<figure-callout\; id="1"\; label="p"\; filenames="DE102021133422A1\_0056.png"\; state="\{\{state\}\}">p</figure-callout>}}_1{\mathrm{\varphi }}_i\left(t\right)\right)+{\text{O}}_{s\mathrm{,1}}\left(\text{t}\right)\right]\end{array}$$

and for the second rotor position sensor of the mold $$\begin{array}{l}{K}_2\left(t\right)={\displaystyle \sum _i^{\infty }{A}_{c\mathrm{,2,}i}\left(t\right)\cdot \text{cos}\left({\mathrm{<figure-callout\; id="2"\; label="p"\; filenames="DE102021133422A1\_0056.png"\; state="\{\{state\}\}">p</figure-callout>}}_2\mathrm{}{\mathrm{\varphi }}_2\mathrm{}\left(t\right)+\mathrm{<figure-callout\; id="2"\; label="\Delta \; \phi "\; filenames="DE102021133422A1\_0056.png"\; state="\{\{state\}\}">\Delta </figure-callout>}{\mathrm{\varphi }}_{}{\mathrm{}}_{\mathrm{2,}i}+{\mathrm{\varphi }}_{1.2}\right)+{\text{O}}_{c\mathrm{,2}}\left(\text{t}\right)}+\\ j\cdot \left[A_{s\mathrm{,2,}i}\cdot \text{sin}\left({\mathrm{<figure-callout\; id="2"\; label="p"\; filenames="DE102021133422A1\_0056.png"\; state="\{\{state\}\}">p</figure-callout>}}_2{\mathrm{\varphi }}_i\left(t\right)++{\mathrm{\varphi }}_{1.2}\right)+{\text{O}}_{s\mathrm{,2}}\left(\text{t}\right)\right]\end{array}$$

be.

The indices 1 and 2 stand for the first and the second rotor position sensor, j is the imaginary unit, p ₁ , p ₂ are the pole pair numbers for the first and second rotor position sensor, ϕ _i (t) = ω _0i t + δ _i der time-dependent angle of the rotor with a phase shift δ _i between different fundamental and harmonics, Δϕ _1/2,i the deviation of the angle of the two axes from 90°, ϕ _1,2 the phase shift of the rotor position signals, A _c,1/2,i (t) and A _s,1/2,i (t) the amplitudes of the fundamental (j = 1) and the harmonics (i > 1) of the real and imaginary parts of the trigonometric function and O _c,1/2 (t) and O _s,1/2 (t) offsets of the real and imaginary parts.

In other words, the amplitudes A _c,1,i (t) and A _s,1,i (t) are the amplitudes of the fundamental (j=1) and harmonics (i>1) of the real and imaginary parts, respectively, of the first Angle function K ₁ and the amplitudes A _c,2,i (t) and A _s,2,i (t) the amplitudes of the fundamental (j = 1) and the harmonics (i > 1) of the real part and the imaginary part of the second angle function K ₂ . The same applies to the other parameters. In practice it has turned out that with these angle functions a very efficient processing of the rotor position signals is possible and that the angle and/or the angular velocity are determined very precisely in this way.

In one embodiment of the invention, the filter module applies a filter based on a complex phase locked loop to the complex trigonometric functions. Such controllers have the advantage that they have a low settling time and low noise. The angle and/or the angular velocity is thus determined very precisely.

The filter can suppress orders i>3, in particular i>1. The filter can therefore be used to filter out certain frequency ranges, that is to say certain harmonics of the rotor position signals, which increases the calculation speed of the angle and/or the angular velocity.

$${\mathrm{\theta }}_{s\mathrm{,1}}\left(t\right)=p_1\cdot \left({\omega }_i\cdot t+{\delta }_{\mathrm{1,}i}\right),$$

$${\mathrm{\theta }}_{c\mathrm{,2}}\left(t\right)=p_2\cdot \left({\omega }_i\cdot t+{\delta }_{\mathrm{2,}i}\right)+\Delta {\mathrm{\varphi }}_{\mathrm{2,}i}+{\mathrm{\varphi }}_{\mathrm{1,2}},$$

$${\mathrm{\theta }}_{s\mathrm{,2}}\left(t\right)=p_2\cdot \left({\omega }_i\cdot t+{\delta }_{\mathrm{2,}i}\right)+{\mathrm{\varphi }}_{\mathrm{1,2}},$$

$$\frac{d{A}_{c,m,i}\left(t\right)}{dt}={\mu }_{\text{m}\text{,1}\text{,}i}\cdot \left\{E_{c,m,i}\left(t\right)\cdot \text{cos}\left({\mathrm{\theta }}_{c,m}\left(t\right)\right)\right\},$$

$$\frac{d{A}_{s,m,i}\left(t\right)}{dt}={\mu }_{\text{m}\text{,1}\text{,}i}\cdot \left\{E_{s\mathrm{,1,}i}\left(t\right)\cdot \text{sin}\left({\mathrm{\theta }}_{s,m}\left(t\right)\right)\right\},$$

$$\frac{d{O}_{c,m}\left(t\right)}{dt}={\mu }_{\text{m}\text{,2}}\cdot \left\{E_{c,m,i}\left(t\right)\right\},$$

$$\frac{d{O}_{s,m}\left(t\right)}{dt}={\mu }_{\text{m}\text{,2}}\cdot \left\{E_{s,m,i}\left(t\right)\right\},$$

$$\frac{d\Delta {\mathrm{\varphi }}_{m,i}\left(t\right)}{dt}={\mu }_{\text{m}\text{,3}\text{,i}}\cdot E_{c,m,i}\left(t\right)\text{sin}\left({\mathrm{\theta }}_{c,m}\left(t\right)\right),$$

$$\frac{d{\mathrm{\varphi }}_{\mathrm{1,2}}\left(t\right)}{dt}={\mu }_{\mathrm{4,}i}+\left\{E_{s\mathrm{,2,}i}\left(\text{t}\right)\cdot \text{cos}\left({\mathrm{\theta }}_{s\mathrm{,2}}\left(t\right)\right)-E_{c\mathrm{,2,}i}\left(t\right)\cdot \text{sin}\left({\mathrm{\theta }}_{c\mathrm{,2}}\left(t\right)\right)\right\},$$

$$\frac{d{a}_i\left(t\right)}{dt}={\mu }_{\mathrm{5,}i}\cdot {\displaystyle \sum {}_m\left\{E_{s,m,i}\left(t\right)\cdot \text{cos}\left({\mathrm{\theta }}_{s,m}\left(t\right)\right)-E_{c,m,i}\left(t\right)\cdot \text{sin}\left({\mathrm{\theta }}_{c,m}\left(t\right)\right)\right\}},$$

$$\frac{d{\omega }_i\left(t\right)}{dt}={\mu }_{\mathrm{6,}i}{\displaystyle \sum {}_m\left\{E_{s,m,i}\left(t\right)\cdot \text{cos}\left({\mathrm{\theta }}_{s,m}\left(t\right)\right)-E_{c,m,i}\left(t\right)\cdot \text{sin}\left({\mathrm{\theta }}_{c,m}\left(t\right)\right)\right\}}+a_i\left(t\right),$$

$$\frac{d{\mathrm{\varphi }}_i\left(tt\right)}{dt}={\mu }_{\mathrm{7,}i}\cdot {\displaystyle \sum {}_m\left\{E_{s,m,i}\left(t\right)\cdot \text{cos}\left({\mathrm{\theta }}_{s,m}\left(t\right)\right)-E_{c,m,i}\left(t\right)\cdot \text{sin}\left({\theta }_{c,m}\left(t\right)\right)\right\}}+{\omega }_i\left(t\right),$$

$$\begin{array}{r}{F}_{m,i}\left(t\right)=A_{c,m,i}\cdot \text{cos}\left({\mathrm{\theta }}_{c,m}\left(t\right)\right)+O_{c,m}+\\ j\cdot \left(A_{s,m,i}\cdot \text{sin}\left({\mathrm{\theta }}_{s,m}\left(t\right)\right)+{\text{O}}_{s,m}\right),\end{array}$$

$$$$

$$E_{m,i}\left(t\right)=K_m\left(t\right)-F_{m,i}\left(t\right),$$

$${\mathrm{\varphi }}_i\left(t\right)={\omega }_i\cdot t+{\delta }_{m,i},$$

In one embodiment, the filter is described by the following equations: $${\mathrm{\theta }}_{c\mathrm{,1}}\left(t\right)=p_1\cdot \left({\omega }_i\cdot t+{\delta }_{\mathrm{1,}i}\right)+\Delta {\mathrm{\varphi }}_{\mathrm{1,}i},$$

$${\mathrm{\theta }}_{s\mathrm{,1}}\left(t\right)=p_1\cdot \left({\omega }_i\cdot t+{\delta }_{\mathrm{1,}i}\right),$$

$${\mathrm{\theta }}_{c\mathrm{,2}}\left(t\right)=p_2\cdot \left({\omega }_i\cdot t+{\delta }_{\mathrm{2,}i}\right)+\Delta {\mathrm{\varphi }}_{\mathrm{2,}i}+{\mathrm{\varphi }}_{1.2},$$

$${\mathrm{\theta }}_{s\mathrm{,2}}\left(t\right)=p_2\cdot \left({\omega }_i\cdot t+{\delta }_{\mathrm{2,}i}\right)+{\mathrm{\varphi }}_{1.2},$$

$$\frac{\mathrm{i.e}{A}_{c,m,i}\left(t\right)}{\mathrm{i.e}t}={\mu }_{\text{m}\text{,1}\text{,}i}\cdot \left\{E_{c,m,i}\left(t\right)\cdot \text{cos}\left({\mathrm{\theta }}_{c,m}\left(t\right)\right)\right\},$$

$$\frac{\mathrm{i.e}{A}_{s,m,i}\left(t\right)}{\mathrm{i.e}t}={\mu }_{\text{m}\text{,1}\text{,}i}\cdot \left\{E_{s\mathrm{,1,}i}\left(t\right)\cdot \text{sin}\left({\mathrm{\theta }}_{s,m}\left(t\right)\right)\right\},$$

$$\frac{\mathrm{i.e}{O}_{c,m}\left(t\right)}{\mathrm{i.e}t}={\mu }_{\text{m}\text{,2}}\cdot \left\{E_{c,m,i}\left(t\right)\right\},$$

$$\frac{\mathrm{i.e}{O}_{s,m}\left(t\right)}{\mathrm{i.e}t}={\mu }_{\text{m}\text{,2}}\cdot \left\{E_{s,m,i}\left(t\right)\right\},$$

$$\frac{\mathrm{i.e}\Delta {\mathrm{\varphi }}_{m,i}\left(t\right)}{\mathrm{i.e}t}={\mu }_{\text{m}\text{,3}\text{, i}}\cdot E_{c,m,i}\left(t\right)\text{sin}\left({\mathrm{\theta }}_{c,m}\left(t\right)\right),$$

$$\frac{\mathrm{i.e}{\mathrm{\varphi }}_{1.2}\left(t\right)}{\mathrm{i.e}t}={\mu }_{\mathrm{4,}i}+\left\{E_{s\mathrm{,2,}i}\left(\text{t}\right)\cdot \text{cos}\left({\mathrm{\theta }}_{s\mathrm{,2}}\left(t\right)\right)-E_{c\mathrm{,2,}i}\left(t\right)\cdot \text{sin}\left({\mathrm{\theta }}_{c\mathrm{,2}}\left(t\right)\right)\right\},$$

$$\frac{\mathrm{i.e}{a}_i\left(t\right)}{\mathrm{i.e}t}={\mu }_{\mathrm{5,}i}\cdot {\displaystyle \sum {}_m\left\{E_{s,m,i}\left(t\right)\cdot \text{cos}\left({\mathrm{\theta }}_{s,m}\left(t\right)\right)-E_{c,m,i}\left(t\right)\cdot \text{sin}\left({\mathrm{\theta }}_{c,m}\left(t\right)\right)\right\}},$$

$$\frac{\mathrm{i.e}{\omega }_i\left(t\right)}{\mathrm{i.e}t}={\mu }_{\mathrm{6,}i}{\displaystyle \sum {}_m\left\{E_{s,m,i}\left(t\right)\cdot \text{cos}\left({\mathrm{\theta }}_{s,m}\left(t\right)\right)-E_{c,m,i}\left(t\right)\cdot \text{sin}\left({\mathrm{\theta }}_{c,m}\left(t\right)\right)\right\}}+a_i\left(t\right),$$

$$\frac{\mathrm{i.e}{\mathrm{\varphi }}_i\left(tt\right)}{\mathrm{i.e}t}={\mu }_{\mathrm{7,}i}\cdot {\displaystyle \sum {}_m\left\{E_{s,m,i}\left(t\right)\cdot \text{cos}\left({\mathrm{\theta }}_{s,m}\left(t\right)\right)-E_{c,m,i}\left(t\right)\cdot \text{sin}\left({\theta }_{c,m}\left(t\right)\right)\right\}}+{\omega }_i\left(t\right),$$

$$\begin{array}{r}{f}_{m,i}\left(t\right)=A_{c,m,i}\cdot \text{cos}\left({\mathrm{\theta }}_{c,m}\left(t\right)\right)+O_{c,m}+\\ j\cdot \left(A_{s,m,i}\cdot \text{sin}\left({\mathrm{\theta }}_{s,m}\left(t\right)\right)+{\text{O}}_{s,m}\right),\end{array}$$

$$$$

$$E_{m,i}\left(t\right)=K_m\left(t\right)-f_{m,i}\left(t\right),$$

$${\mathrm{\varphi }}_i\left(t\right)={\omega }_i\cdot t+{\delta }_{m,i},$$

die zeitliche Ableitung, a_i(t) die Beschleunigung, $F_1\left(t\right)={\displaystyle {\sum }_{i=1}^n{F}_{\mathrm{1,}i}\left(t\right),F_2\left(t\right)=}{\displaystyle {\sum }_{i=1}^n{F}_{\mathrm{2,}i}\left(t\right)}$

das Filtersignal mit den Filterkomponenten F_m,i(t) sowie E_m,i(t) die Fehlerfunktion zwischen der komplexen Winkelfunktion K_m(t) und den Filterkomponenten F_m,i(t).where µ _m,n,i (m=1,2; n=1-6) are amplification factors, m is an index for the corresponding rotor position sensor (m=1 or 2), $\frac{\mathrm{i.e}}{\mathrm{i.e}t}$

the time derivative, a _i (t) the acceleration, $f_1\left(t\right)={\displaystyle {\sum }_{i=1}^{\mathrm{<figure-callout\; id="1"\; label="n\; f"\; filenames="DE102021133422A1\_0056.png"\; state="\{\{state\}\}">n</figure-callout>}}{f}_{}{}_{\mathrm{1,}i}\left(t\right),f_2\left(t\right)=}{\displaystyle {\sum }_{i=1}^{\mathrm{<figure-callout\; id="2"\; label="n\; f"\; filenames="DE102021133422A1\_0056.png"\; state="\{\{state\}\}">n</figure-callout>}}{f}_{}{}_{\mathrm{2,}i}\left(t\right)}$

the filter signal with the filter components F _m,i (t) and E _m,i (t) the error function between the complex angle function K _m (t) and the filter components F _m,i (t).

The filter can be stored as a transfer function in the filter module. This enables efficient processing of the rotor position signal.

In other words, the filter is stored in a memory of the controller.

In order to obtain status information, the regulator can have a diagnostics module which is signal-connected to the filter module. The diagnostic module receives at least one determined parameter of the filter and derives a state of the electric motor, the filter and/or the rotor position sensor from the parameter received. The at least one parameter is therefore used to diagnose the electric motor, the rotor position sensor and/or the filter.

The object is also achieved according to the invention by a controller for a motor vehicle, the controller being designed to carry out a method according to the invention. With regard to the advantages and features, reference is made to the above explanations relating to the method according to the invention, which apply equally to the controller.

In addition, the object is achieved according to the invention by a motor vehicle with an electric motor and a controller according to the invention. The advantages and features already explained with regard to the method and the controller result.

• - 1 eine schematische Seitenansicht eines erfindungsgemäßen Kraftfahrzeugs mit einem erfindungsgemäßen Regler,
• - 2 ein schematisches Blockschaltbild eines Elektromotors und des erfindungsgemäßen Reglers aus 1,
• - 3 ein detailliertes Blockschaltbild des Elektromotors und des erfindungsgemäßen Reglers aus 2, und
• - 4 ein Blockschaltbild eines Filtermoduls aus 3.

Further features and advantages of the invention result from the following description and from the accompanying drawings, to which reference is made below. In the drawings show:

• - 1 a schematic side view of a motor vehicle according to the invention with a controller according to the invention,
• - 2 a schematic block diagram of an electric motor and the controller according to the invention 1 ,
• - 3 a detailed block diagram of the electric motor and the controller according to the invention 2 , and
• - 4 a block diagram of a filter module 3 .

1 12 shows a schematic side view of a motor vehicle 10 having an electric motor 12 and a controller 14. FIG. The electric motor 12 is connected to the wheels of the motor vehicle 10 and provides for the propulsion of the motor vehicle 10. The motor vehicle 10 can be an electric motor vehicle or a hybrid electric motor vehicle.

The block diagram of 2 FIG. 1 shows the electric motor 12, the controller 14, a first rotor position sensor 16 and a second rotor position sensor 17 in detail.

The electric motor 12 is, for example, a known synchronous three-phase machine and has a stator 18 and a rotor 20.

The stator 18 encloses the rotor 20 and has three electromagnets 22 on its inside, i.e. on the side of the stator 18 which is opposite the rotor 20.

The three electromagnets 22 are offset from one another at an angle of 120° and, in a manner known per se, the application of a voltage to the electromagnet 22, more precisely to coils 24, causes the magnetic rotor 20 to rotate (represented by a north pole N and a south pole S in 3 ) generated.

In the exemplary embodiment shown, the rotor 20 rotates at an angular velocity w about an axis of rotation 26 and the rotor 20 has an angle φ with respect to a first axis 30 .

The rotation of the rotor 20 about the axis of rotation 26 defines a plane of rotation 28 which is spanned by axes 30, 32 of the corresponding rotor position sensors 16, 17. The axes 30, 32 have an angle α to each other.

In general, the angle α is different for the first and second rotor position sensors 16, 17.

The rotor position sensors 16, 17 are magnetoresistive sensors and accordingly detect the rotational movement of the rotor 20 without contact.

More specifically, each rotor position sensor 16, 17 provides a rotor position signal P ₁ , P ₂ . This means that the first rotor position sensor 16 provides the first rotor position signal P ₁ and the second rotor position sensor 17 provides the second rotor position signal P ₂ .

Each rotor position signal P ₁ , P ₂ has a position value along the first axis 30 and one along the second axis 32 . In the block diagram of 3 the position values are shown as an example for the first rotor position signal P ₁ .

In order to obtain the most accurate possible determination of the angle φ and the angular velocity ω, the controller 14 processes the rotor position signals P ₁ , P ₂ together. The controller 14 thus performs a type of data fusion of the first rotor position signal P ₁ with the second rotor position signal P ₂ .

For this data fusion, a method is implemented in the controller 14, which is based on the below 3 and 4 is explained.

In a first step, the controller 14 receives the rotor position signals P ₁ , P ₂ from the rotor position sensor 16.

More precisely, the first rotor position signal P ₁ is passed to a first pre-processing module 34 and the second rotor position signal P ₂ is passed to a second pre-processing module 35 .

wobei j die imaginäre Einheit ist, R der Realteil und I der Imaginärteil der komplexen Winkelfunktion.The pre-processing modules 34, 35 then determine from the rotor position signals P ₁ , P ₂ complex trigonometric functions K ₁ , K ₂ of the form $$K=R+j\cdot I,$$

where j is the imaginary unit, R is the real part and I is the imaginary part of the complex trigonometric function.

The mode of operation of the preprocessing module 34 and the filter module 36 is explained below using an example. For this purpose it is assumed that the rotor position signals P ₁ , P ₂ are transferred to the pre-processing module 34 as time-dependent rotor position signals P ₁ (t), P ₂ (t).

The time-dependent rotor position signals P ₁ (t) P ₂ (t) are each composed of the movement x _m,1 (t) = A _c,m,1 cos(p _m *(ω * t + δ _1,m )) along of the first axis 30, is composed of the movement x _m,2 (t) = A _s,m,1 sin( _pm * ω * t + δ _1,m )) of the rotor 20 along the second axis 32 and respective error terms x _m,F1 (t),x _m,F2 (t). In this case, δ ₁ is the starting angle of rotor 20 at time t=0, p _m is the number of pole pairs for the first and second rotor position sensors 16, 17, the angle φ(t) of rotor 20 is given by φ(t) = ω t + δ _1,m and m is the index for the first or second rotor position signal P ₁ , P ₂ , i.e. m=1 or 2.

In addition to the actual number of poles of the electric motor 12, the number of pole pairs p _m is also dependent on the sensor principle of the first and second rotor position sensors 16, 17. Correspondingly, in the case of an electric motor 12, different numbers of pole pairs p _m can result for the rotor position sensors 16, 17.

und $$P_2\left(t\right)=x_{\mathrm{2,1}}\left(t\right)+x_{\mathrm{2,}F1}\left(t\right)+j\left(x_{\mathrm{2,2}}\left(t\right)+x_{\mathrm{2,}F2}\left(t\right)\right).$$

Accordingly, in complex notation, the rotor position signals are given by: $$P_1\left(t\right)=x_{1.1}\left(t\right)+x_{\mathrm{1,}f1}\left(t\right)+j\left(x_{1.2}\left(t\right)+x_{\mathrm{1,}f2}\left(t\right)\right),$$

and $$P_2\left(t\right)=x_{2.1}\left(t\right)+x_{\mathrm{2,}f1}\left(t\right)+j\left(x_{2.2}\left(t\right)+x_{\mathrm{2,}f2}\left(t\right)\right).$$

The error terms x _F1 (t), x _F2 (t) are the respective projections of the sum of the unwanted signals, such as harmonics, offsets, phase shifts between the rotor position signals, orthogonality errors and/or gain errors along the two axes 30, 32.

These errors arise, for example, through the measurement of the rotor position sensors 16, 17 through the conversion of an analog signal into a digital one and/or are the result of a stray field. Furthermore, the error terms can also be caused by errors in the evaluation electronics, by the assembly of the electric motor 12 and/or by the aging of the rotor position sensors 16, 17.

If the error terms x _F1 (t), x _F2 (t) are not taken into account appropriately in the analysis, inaccuracies can arise in the determination of the angle φ of the rotor 20, so that the electric motor 12 runs unevenly and/or has harmonics in the torque.

To compensate for these errors, an offset O of the rotor position signals, the deviation Δϕ of the axis angle α from 90° of each rotor position sensor 16, 17, a phase shift ϕ _1.2 between the first and the second rotor position signal P ₁ , P ₂ and higher orders taken into account when determining the complex trigonometric functions K ₁ , K ₂ .

$$$$

und $$\begin{array}{c}{K}_2\left(t\right)={\displaystyle \sum _i^{\infty }{A}_{c\mathrm{,2,}i}\left(t\right)\cdot \text{cos}\left(p_2\mathrm{ }{\mathrm{\varphi }}_i\mathrm{ }\left(t\right)+\Delta {\mathrm{\varphi }}_{\mathrm{2,}i}+{\mathrm{\varphi }}_{\mathrm{1,2}}\right)+{\text{O}}_{c\mathrm{,2}}\left(\text{t}\right)}+\\ j\cdot \left[A_{s\mathrm{,2,}i}\left(t\right)\cdot \text{sin}\left(p_2{\mathrm{\varphi }}_i\left(t\right)+{\mathrm{\varphi }}_{\mathrm{1,2}}\right)+{\text{O}}_{s\mathrm{,2}}\left(\text{t}\right)\right].\end{array}$$

$$$$

The pre-processing module 34 forms a complex trigonometric series for both position signals P ₁ (t ₎ , P ₂ (t) and the first angular function K ₁ of the first rotor position signal P ₁ and the second complex angular function K ₂ of the second rotor position signal P ₂ result as: $$\begin{array}{c}{K}_1\left(t\right)={\displaystyle \sum _i^{\infty }{A}_{c\mathrm{,1,}i}\left(t\right)\cdot \text{cos}\left({\mathrm{<figure-callout\; id="1"\; label="p"\; filenames="DE102021133422A1\_0056.png"\; state="\{\{state\}\}">p</figure-callout>}}_1\mathrm{}{\mathrm{\varphi }}_i\mathrm{}\left(t\right)+\mathrm{<figure-callout\; id="1"\; label="\Delta \; \phi "\; filenames="DE102021133422A1\_0056.png"\; state="\{\{state\}\}">\Delta </figure-callout>}{\mathrm{\varphi }}_{}{\mathrm{}}_{\mathrm{1,}i}\right)+{\text{O}}_{c\mathrm{,1}}\left(\text{t}\right)}+\\ j\cdot \left[A_{s\mathrm{,1,}i}\cdot \text{sin}\left({\mathrm{<figure-callout\; id="1"\; label="p"\; filenames="DE102021133422A1\_0056.png"\; state="\{\{state\}\}">p</figure-callout>}}_1{\mathrm{\varphi }}_i\left(t\right)\right)+{\text{O}}_{s\mathrm{,1}}\left(\text{t}\right)\right]\end{array}$$

$$$$

and $$\begin{array}{c}{K}_2\left(t\right)={\displaystyle \sum _i^{\infty }{A}_{c\mathrm{,2,}i}\left(t\right)\cdot \text{cos}\left({\mathrm{<figure-callout\; id="2"\; label="p"\; filenames="DE102021133422A1\_0056.png"\; state="\{\{state\}\}">p</figure-callout>}}_2\mathrm{}{\mathrm{\varphi }}_i\mathrm{}\left(t\right)+\mathrm{<figure-callout\; id="2"\; label="\Delta \; \phi "\; filenames="DE102021133422A1\_0056.png"\; state="\{\{state\}\}">\Delta </figure-callout>}{\mathrm{\varphi }}_{}{\mathrm{}}_{\mathrm{2,}i}+{\mathrm{\varphi }}_{1.2}\right)+{\text{O}}_{c\mathrm{,2}}\left(\text{t}\right)}+\\ j\cdot \left[A_{s\mathrm{,2,}i}\left(t\right)\cdot \text{sin}\left({\mathrm{<figure-callout\; id="2"\; label="p"\; filenames="DE102021133422A1\_0056.png"\; state="\{\{state\}\}">p</figure-callout>}}_2{\mathrm{\varphi }}_i\left(t\right)+{\mathrm{\varphi }}_{1.2}\right)+{\text{O}}_{s\mathrm{,2}}\left(\text{t}\right)\right].\end{array}$$

$$$$

Where φ _i (t) = i ω t + δ _m,i is the time-dependent angle of the rotor 20 (m=1 or 2) with a phase offset δ _m,i between different fundamental and harmonics, Δφ _m,i the Deviation of the axis angle α between different fundamental and harmonics of the first and the second rotor position sensor as well as A _c,m,i (t) and A _s,m,i (t) the amplitudes of the fundamental (j = 1) and the harmonics (i > 1).

In general, the deviation Δφ _m,i of the axis angle α can of course also be taken into account in the imaginary part and/or the phase offset φ _1,2 in the complex angular function of the first rotor position signal P ₁ .

The parameters Π of the complex trigonometric functions K ₁ , K ₂ are therefore given by A _c,m,i (t), A _s,m,i (t), O _s,m (t), O _c,m (t) , Δϕ _m,i , ϕ _1,2 and δ _m,i .

The complex angle functions K ₁ , K ₂ are then transferred to a filter module 36 which determines the parameters Π, the angular velocity w and the angle φ of the rotor 20 from the complex angle functions K ₁ , K ₂ .

$$$$

$$\begin{array}{c}{F}_2\left(t\right)={\displaystyle \sum _i^n\{A_{c\mathrm{,2,}i}\left(t\right)\cdot \text{cos}\left(p_2{\mathrm{\varphi }}_i\left(t\right)+\Delta {\mathrm{\varphi }}_{\mathrm{2,}i}+{\mathrm{\varphi }}_{\mathrm{1,2}}\right)+{\text{O}}_{c\mathrm{,2}}\left(\text{t}\right)}+\\ j\cdot \left[A_{s\mathrm{,2,}i}\left(t\right)\cdot \text{sin}\left(p_2{\mathrm{\varphi }}_i\left(t\right)+{\mathrm{\varphi }}_{\mathrm{1,2}}\right)+{\text{O}}_{s\mathrm{,2}}\left(\text{t}\right)\right]\}.\end{array}$$

$$$$

The filter module 36 uses a filter 42 to determine the filter signals F ₁ (t), F ₂ (t) of the form $$\begin{array}{c}{f}_1\left(t\right)={\displaystyle \sum _i^n\{A_{c\mathrm{,1,}i}\left(t\right)\cdot \text{cos}\left({\mathrm{<figure-callout\; id="1"\; label="p"\; filenames="DE102021133422A1\_0056.png"\; state="\{\{state\}\}">p</figure-callout>}}_1{\mathrm{\varphi }}_i\left(t\right)+\mathrm{<figure-callout\; id="1"\; label="\Delta \; \phi "\; filenames="DE102021133422A1\_0056.png"\; state="\{\{state\}\}">\Delta </figure-callout>}{\mathrm{\varphi }}_{}{\mathrm{}}_{\mathrm{1,}i}\right)+{\text{O}}_{c\mathrm{,1}}\left(\text{t}\right)}+\\ j\cdot \left[A_{s\mathrm{,1,}i}\cdot \text{sin}\left({\mathrm{<figure-callout\; id="1"\; label="p"\; filenames="DE102021133422A1\_0056.png"\; state="\{\{state\}\}">p</figure-callout>}}_1{\mathrm{\varphi }}_i\left(t\right)\right)+{\text{O}}_{s\mathrm{,1}}\left(\text{t}\right)\right]\}\end{array}$$

$$$$

$$\begin{array}{c}{f}_2\left(t\right)={\displaystyle \sum _i^n\{A_{c\mathrm{,2,}i}\left(t\right)\cdot \text{cos}\left({\mathrm{<figure-callout\; id="2"\; label="p"\; filenames="DE102021133422A1\_0056.png"\; state="\{\{state\}\}">p</figure-callout>}}_2{\mathrm{\varphi }}_i\left(t\right)+\mathrm{<figure-callout\; id="2"\; label="\Delta \; \phi "\; filenames="DE102021133422A1\_0056.png"\; state="\{\{state\}\}">\Delta </figure-callout>}{\mathrm{\varphi }}_{}{\mathrm{}}_{\mathrm{2,}i}+{\mathrm{\varphi }}_{1.2}\right)+{\text{O}}_{c\mathrm{,2}}\left(\text{t}\right)}+\\ j\cdot \left[A_{s\mathrm{,2,}i}\left(t\right)\cdot \text{sin}\left({\mathrm{<figure-callout\; id="2"\; label="p"\; filenames="DE102021133422A1\_0056.png"\; state="\{\{state\}\}">p</figure-callout>}}_2{\mathrm{\varphi }}_i\left(t\right)+{\mathrm{\varphi }}_{1.2}\right)+{\text{O}}_{s\mathrm{,2}}\left(\text{t}\right)\right]\}.\end{array}$$

$$$$

It should be noted that the filter signals F(t) have only a finite number of harmonics, i.e. n < ∞. For example, only orders up to n=3 or up to n=1 are taken into account.

In other words, the high i-value harmonics are filtered out so that the filter 42 acts as a band pass or low pass.

und die Minimierung der Kostenfunktion mittels des Gradientenverfahrens bestimmen, sodass die zeitlichen Ableitungen der Parameter Π gegeben ist durch $$\frac{\text{d}\mathrm{\Pi }\left(\text{t}\right)}{\text{dt}}=-\mu \Re e\left\{\frac{\partial }{\partial \mathrm{\Pi }}J\left(t,\mathrm{\Pi }\right)\right\}=-\mu \Re e\left\{E_m*\left(t,\mathrm{\Pi }\right)\cdot \frac{\partial E_m\left(t,\mathrm{\Pi }\right)}{\partial \mathrm{\Pi }}\right\}.$$

The parameters Π of the filter signals F ₁ (t), F ₂ (t) can be calculated by forming a cost function J(t, Π) $$J\left(t,\mathrm{\Pi }\right)=\frac{1}{2}{\left[P_m\left(t\right)-f_m\left(t,\mathrm{\Pi }\right)\right]}^2=\frac{1}{2}{E}_m{\left(t,\mathrm{\Pi }\right)}^2$$

and determine the minimization of the cost function using the gradient method, so that the time derivatives of the parameters Π are given by $$\frac{\text{i.e}\mathrm{\Pi }\left(\text{t}\right)}{\text{German}}=-\mu \Re e\left\{\frac{\partial }{\partial \mathrm{\Pi }}J\left(t,\mathrm{\Pi }\right)\right\}=-\mu \Re e\left\{E_m*\left(t,\mathrm{\Pi }\right)\cdot \frac{\partial E_m\left(t,\mathrm{\Pi }\right)}{\partial \mathrm{\Pi }}\right\}.$$

In this case μ is a matrix with the amplification factors μ _m,ii and also known as the step sizes of the gradient method, E _m (t, Π) are the error signals and E*(t, Π) are the complex conjugate error signals.

$${\mathrm{\theta }}_{s\mathrm{,1}}\left(t\right)=p_1\cdot \left({\omega }_i\cdot t+{\delta }_{\mathrm{1,}i}\right),$$

$${\mathrm{\theta }}_{c\mathrm{,2}}\left(t\right)=p_2\cdot \left({\omega }_i\cdot t+{\delta }_{\mathrm{2,}i}\right)+\Delta {\mathrm{\varphi }}_{\mathrm{2,}i}+{\mathrm{\varphi }}_{\mathrm{1,2}},$$

$${\mathrm{\theta }}_{s\mathrm{,2}}\left(t\right)=p_2\cdot \left({\omega }_i\cdot t+{\delta }_{\mathrm{2,}i}\right)+{\mathrm{\varphi }}_{\mathrm{1,2}},$$

$$\frac{d{A}_{c,m,i}\left(t\right)}{dt}={\mu }_{\text{m}\text{,1}\text{,}i}\cdot \left\{E_{c,m,i}\left(t\right)\cdot \text{cos}\left({\mathrm{\theta }}_{c,m}\left(t\right)\right)\right\},$$

$$\frac{d{A}_{s,m,i}\left(t\right)}{dt}={\mu }_{\text{m}\text{,1}\text{,}i}\cdot \left\{E_{s\mathrm{,1,}i}\left(t\right)\cdot \text{sin}\left({\mathrm{\theta }}_{s,m}\left(t\right)\right)\right\},$$

$$\frac{d{O}_{c,m}\left(t\right)}{dt}={\mu }_{\text{m}\text{,2}}\cdot \left\{E_{c,m,i}\left(t\right)\right\},$$

$$\frac{d{O}_{s,m}\left(t\right)}{dt}={\mu }_{\text{m}\text{,2}}\cdot \left\{E_{s,m,i}\left(t\right)\right\},$$

$$\frac{d\Delta {\mathrm{\varphi }}_{m,i}\left(t\right)}{dt}={\mu }_{\text{m}\text{,3}\text{,i}}\cdot E_{c,m,i}\left(t\right)\text{sin}\left({\mathrm{\theta }}_{c,m}\left(t\right)\right),$$

$$\frac{d{\mathrm{\varphi }}_{\mathrm{1,2}}\left(t\right)}{dt}={\mu }_{\mathrm{4,}i}\cdot \left\{E_{s\mathrm{,2,}i}\left(t\right)\cdot \text{cos}\left({\mathrm{\theta }}_{s\mathrm{,2}}\left(t\right)\right)-E_{c\mathrm{,2,}i}\left(t\right)\cdot \text{sin}\left({\mathrm{\theta }}_{c\mathrm{,2}}\left(t\right)\right)\right\},$$

$$\frac{d{a}_i\left(t\right)}{dt}={\mu }_{\mathrm{5,}i}{\displaystyle \sum {}_m\left\{E_{s,m,i}\left(t\right)\cdot \text{cos}\left({\mathrm{\theta }}_{s,m}\left(t\right)\right)-E_{c,m,i}\left(t\right)\cdot \text{sin}\left({\mathrm{\theta }}_{c,m}\left(t\right)\right)\right\}},$$

$$\begin{array}{l}\frac{d{\omega }_i\left(t\right)}{dt}={\mu }_{\mathrm{6,}i}{\displaystyle \sum {}_m\left\{E_{s,m,i}\left(t\right)\cdot \text{cos}\left({\mathrm{\theta }}_{s,m}\left(t\right)\right)-E_{c,m,i}\left(t\right)\cdot \text{sin}\left({\theta }_{c,m}\left(t\right)\right)\right\}}\\ +a_i\left(t\right),\end{array}$$

$$\begin{array}{l}\frac{d{\mathrm{\varphi }}_i\left(t\right)}{dt}={\mu }_{\mathrm{7,}i}\cdot {\displaystyle \sum {}_m\left\{E_{s,m,i}\left(t\right)\cdot \text{cos}\left({\mathrm{\theta }}_{s,m}\left(t\right)\right)-E_{c,m,i}\left(t\right)\cdot \text{sin}\left({\mathrm{\theta }}_{c,m}\left(t\right)\right)\right\}}\\ +{\omega }_i\left(t\right),\end{array}$$

$$\begin{array}{l}{F}_{m,i}\left(t\right)=A_{c,m,i}\cdot \text{cos}\left({\mathrm{\theta }}_{c,m}\left(t\right)\right)+O_{c,m}+\\ j\cdot \left(A_{s,m,i}\cdot \text{sin}\left({\mathrm{\theta }}_{s,m}\left(t\right)\right)+O_{s,m}\right),\end{array}$$

$$$$

$$E_{m,i}\left(t\right)=K_m\left(t\right)-F_{m,i}\left(t\right),$$

$${\mathrm{\varphi }}_i\left(t\right)={\omega }_i\cdot t+{\delta }_{m,i},$$

Accordingly, the following equations result for the filter 42: $${\mathrm{\theta }}_{c\mathrm{,1}}\left(t\right)=p_1\cdot \left({\omega }_i\cdot t+{\delta }_{\mathrm{1,}i}\right)+\Delta {\mathrm{\varphi }}_{\mathrm{1,}i},$$

$${\mathrm{\theta }}_{s\mathrm{,1}}\left(t\right)=p_1\cdot \left({\omega }_i\cdot t+{\delta }_{\mathrm{1,}i}\right),$$

$${\mathrm{\theta }}_{c\mathrm{,2}}\left(t\right)=p_2\cdot \left({\omega }_i\cdot t+{\delta }_{\mathrm{2,}i}\right)+\Delta {\mathrm{\varphi }}_{\mathrm{2,}i}+{\mathrm{\varphi }}_{1.2},$$

$${\mathrm{\theta }}_{s\mathrm{,2}}\left(t\right)=p_2\cdot \left({\omega }_i\cdot t+{\delta }_{\mathrm{2,}i}\right)+{\mathrm{\varphi }}_{1.2},$$

$$\frac{\mathrm{i.e}{A}_{c,m,i}\left(t\right)}{\mathrm{i.e}t}={\mu }_{\text{m}\text{,1}\text{,}i}\cdot \left\{E_{c,m,i}\left(t\right)\cdot \text{cos}\left({\mathrm{\theta }}_{c,m}\left(t\right)\right)\right\},$$

$$\frac{\mathrm{i.e}{A}_{s,m,i}\left(t\right)}{\mathrm{i.e}t}={\mu }_{\text{m}\text{,1}\text{,}i}\cdot \left\{E_{s\mathrm{,1,}i}\left(t\right)\cdot \text{sin}\left({\mathrm{\theta }}_{s,m}\left(t\right)\right)\right\},$$

$$\frac{\mathrm{i.e}{O}_{c,m}\left(t\right)}{\mathrm{i.e}t}={\mu }_{\text{m}\text{,2}}\cdot \left\{E_{c,m,i}\left(t\right)\right\},$$

$$\frac{\mathrm{i.e}{O}_{s,m}\left(t\right)}{\mathrm{i.e}t}={\mu }_{\text{m}\text{,2}}\cdot \left\{E_{s,m,i}\left(t\right)\right\},$$

$$\frac{\mathrm{i.e}\Delta {\mathrm{\varphi }}_{m,i}\left(t\right)}{\mathrm{i.e}t}={\mu }_{\text{m}\text{,3}\text{, i}}\cdot E_{c,m,i}\left(t\right)\text{sin}\left({\mathrm{\theta }}_{c,m}\left(t\right)\right),$$

$$\frac{\mathrm{i.e}{\mathrm{\varphi }}_{1.2}\left(t\right)}{\mathrm{i.e}t}={\mu }_{\mathrm{4,}i}\cdot \left\{E_{s\mathrm{,2,}i}\left(t\right)\cdot \text{cos}\left({\mathrm{\theta }}_{s\mathrm{,2}}\left(t\right)\right)-E_{c\mathrm{,2,}i}\left(t\right)\cdot \text{sin}\left({\mathrm{\theta }}_{c\mathrm{,2}}\left(t\right)\right)\right\},$$

$$\frac{\mathrm{i.e}{a}_i\left(t\right)}{\mathrm{i.e}t}={\mu }_{\mathrm{5,}i}{\displaystyle \sum {}_m\left\{E_{s,m,i}\left(t\right)\cdot \text{cos}\left({\mathrm{\theta }}_{s,m}\left(t\right)\right)-E_{c,m,i}\left(t\right)\cdot \text{sin}\left({\mathrm{\theta }}_{c,m}\left(t\right)\right)\right\}},$$

$$\begin{array}{l}\frac{\mathrm{i.e}{\omega }_i\left(t\right)}{\mathrm{i.e}t}={\mu }_{\mathrm{6,}i}{\displaystyle \sum {}_m\left\{E_{s,m,i}\left(t\right)\cdot \text{cos}\left({\mathrm{\theta }}_{s,m}\left(t\right)\right)-E_{c,m,i}\left(t\right)\cdot \text{sin}\left({\theta }_{c,m}\left(t\right)\right)\right\}}\\ +a_i\left(t\right),\end{array}$$

$$\begin{array}{l}\frac{\mathrm{i.e}{\mathrm{\varphi }}_i\left(t\right)}{\mathrm{i.e}t}={\mu }_{\mathrm{7,}i}\cdot {\displaystyle \sum {}_m\left\{E_{s,m,i}\left(t\right)\cdot \text{cos}\left({\mathrm{\theta }}_{s,m}\left(t\right)\right)-E_{c,m,i}\left(t\right)\cdot \text{sin}\left({\mathrm{\theta }}_{c,m}\left(t\right)\right)\right\}}\\ +{\omega }_i\left(t\right),\end{array}$$

$$\begin{array}{l}{f}_{m,i}\left(t\right)=A_{c,m,i}\cdot \text{cos}\left({\mathrm{\theta }}_{c,m}\left(t\right)\right)+O_{c,m}+\\ j\cdot \left(A_{s,m,i}\cdot \text{sin}\left({\mathrm{\theta }}_{s,m}\left(t\right)\right)+O_{s,m}\right),\end{array}$$

$$$$

$$E_{m,i}\left(t\right)=K_m\left(t\right)-f_{m,i}\left(t\right),$$

$${\mathrm{\varphi }}_i\left(t\right)={\omega }_i\cdot t+{\delta }_{m,i},$$

The implementation of the filter 42 in the controller 14 is in FIG 4 shown schematically.

The filter 42 has a splitting module 44 via which the complex trigonometric functions K ₁ , K ₂ are split into the imaginary part I and the real part R.

The real parts R and the imaginary parts I are then each transferred to a corresponding comparison module 46 which compares the corresponding imaginary part I and the corresponding real part R with the respective imaginary part F _s,m,i (t) and real part F _c,m,i ( t) of the filter signal F _m,i (t) and thereby determine the error signal E _m,i (t) according to equation (17).

The error signals E _m,i (t), more precisely the real part E _c,m,i (t) and the imaginary part E _s,m,i (t) of each error signal E _m,i (t) are connected to a main module 48, two amplitude modules 50, two offset modules 52 and an axis angle module 54 passed.

In this case, the main module 48 determines the angular velocity ω _i , the acceleration a _i and the angle φ _i according to equations (13) to (15).

In addition, the amplitude modules 50 determine the amplitudes A _c,m,i (t), A _s,m,i (t) using equations (7) and (8), and the offset modules 52 determine the offsets O _c,m (t), O _s,m (t) using equations (9) and (10).

Furthermore, the axis angle module 54 determines the deviation Δφ _m,i of the axis angle α for each rotor position sensor 16, 17 according to equation (11).

In addition, the error signals E _s,2,i (t) and E _c,2,i (t) of the second rotor position signal P ₂ are transferred to corresponding phase offset modules 55, which calculate the phase offset ϕ _1,2 between the first rotor position signal P ₁ and P ₂ determine.

To indicate that the phase shift φ _1.2 is only calculated for the second rotor position signal, the corresponding calculation paths are shown in FIG 4 shown dashed.

The offsets O _c,m (t), O _s,m (t), the amplitudes A _c,m,i (t), A _s,m,i (t), the deviations Δϕ _m,i and the phase shift ϕ _{1 ,2} are then passed to saturation modules 56, which verify that the corresponding parameters are within certain parameter limits.

If one of the parameters O _c (t), O _s (t), A _ci (t), A _{si (} t), Δφ _i exceeds or falls below a parameter limit, the respective saturation module 56 generates an error message M and/or replaces the parameter by the value of the parameter limit.

The parameters Π of the complex trigonometric function K are additionally transferred to a diagnosis module 40 ( 3 ), which diagnoses the electric motor 12, the rotor position sensor 16 and/or the filter 42 using the transmitted parameters Π.

More precisely, the diagnostic module 40 receives the parameters Π, for example the fundamental and harmonic amplitudes A _{si ,} A _ci , the phase offsets δ _i , the deviation Δφ _i of the axis angle α, the phase offset φ _1.2 and/or the offsets O _s O _c , and generates an error message M if one of the parameters Π exceeds or falls below a threshold value specified for this parameter Π.

In other words, the diagnostic module 40 determines the functional status of the rotor position sensors 16, 17. If one of the rotor position sensors 16, 17 is not functioning properly, the corresponding rotor position sensor 16, 17 is marked accordingly in the controller and the corresponding rotor position signal P ₁ , P ₂ is then used at the Determination of the angle ϕ and/or the angular velocity ω not taken into account.

For example, the error state of one of the rotor position sensors 16, 17 is determined based on the course of the phase offset φ _1,2 over time.

The angular velocity ω _i , the angle φ _i and the deviation Δφ _i of the axis angle α are then used to form the respective imaginary parts F _si (t) or real parts F _ci (t) of the filter signal F _i (t) and an to pass an input of the comparison modules 46 .

The filter 42 is therefore based on a complex phase-locked loop.

Then both the angular velocity ω and the angle φ are transferred from the filter module 36 to the current value correction module 38 ( 3 ).

The current value correction module 38 determines a current correction value I' and a corresponding voltage correction value U' based on the angular velocity ω and the angle φ.

Finally, the controller 14 adjusts the current flow through at least one electromagnet 22 of the electric motor 12 ( 2 ) based on the determined current correction value I'.

For example, the controller 14 regulates the at least one electromagnet 22 in such a way that a current with the current correction value I′ flows through the electromagnet 22 .

In general, controller 14 determines different current correction values I′ and voltage correction values U′ for the three electromagnets 22 . For reasons of clarity, however, only one current correction value I′ and one voltage correction value U′ for all electromagnets 22 are shown here.

By using the rotor position signals P ₁ , P ₂ from two rotor position sensors 16 , 17 , ie by data fusion of the two rotor position signals P ₁ , P ₂ , the accuracy of determining the angular velocity ω and the angle φ is improved. In addition, other errors, such as a sensor-intrinsic orthogonality error, a phase offset between the rotor position signals are compensated for by the method described. Thus, the error terms x _F1 (t), x _F2 (t) are taken into account very precisely. In this way, the efficiency of the transmission of the electrical energy is improved and vibrations in the motor vehicle 10 due to harmonics in the electric motor 12 are reduced.

In the embodiment of 2 until 4 two rotor position sensors 16, 17 were used for determining the angular velocity ω and the angle φ. In general, it is also conceivable that more than two rotor position sensors, for example three or four rotor position sensors, are used, each providing a corresponding rotor position signal.

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• DE 102019122558 B4 [0005]

Claims (13)

Method for determining the angle of a rotor and/or the angular velocity of an electric motor (12) which has a rotor (20) and a stator (18) with at least one coil (24), in particular three coils (24), the method comprises the following steps: a) obtaining a first rotor position signal (P ₁ ) from a first rotor position sensor (16) and a second rotor position signal (P ₂ ) from a second rotor position sensor (17) by a controller (14), the first and second rotor position signals (P ₁ , P ₂ ) each comprises a position value along a first of two axes (30, 32) in the plane of rotation (28) of the rotor (20) and a second position value along the second of the two axes (30, 32), where the rotor position signals (P ₁ , P ₂ ) contain several orders (i), and b) determining the angle (φ) of the rotor (20) and/or the angular velocity (ω) using a filter module (36) of the controller (14), wherein the filter module processes the first rotor position signal (P ₁ ) and the second rotor position signal (P ₂ ) together, each as a complex angle function (K ₁ , K ₂ ). procedure after claim 1 , characterized in that the filter module (36) determines a phase offset (φ _1.2 ) between the first and the second rotor position signal (P ₁ , P ₂ ) and when determining the angle (φ) of the rotor (20) and/or of the angular velocity (ω) is taken into account. procedure after claim 1 or 2 , characterized in that the controller (14) concludes the functional state of the two rotor position sensors (16, 17) on the basis of the rotor position signals (P ₁ , P ₂ ), wherein the controller (14) when a fault state is detected in one of the rotor position sensors (16, 17 ) the corresponding rotor position signal (P ₁ , P ₂ ) is not taken into account. procedure after claim 2 and 3 , characterized in that the controller (14) on the basis of the phase offset (φ _1.2 ) on the functional states of the rotor position sensors (16, 17) closes. Method according to one of the preceding claims, characterized in that the filter module (36) determines the axis angle (α _i ) between the two axes of each rotor position signal (P ₁ , P ₂ ) and the axis angles (α _i ) during the determination of the angle (ϕ ) of the rotor (20) and/or the angular velocity (ω) is taken into account. Method according to one of the preceding claims, characterized in that the electric motor (12) is controlled by the controller (14) at least on the basis of the determined angle (ϕ), in particular by the following steps: a) determining at least one current correction value (I') for the at least one coil (24) by the controller (14) based on the determined angle (φ), and b) adjustment of the current flow through the at least one coil (24) based on the at least one current correction value (I') by the controller (14) . Method according to one of the preceding claims, characterized in that the first rotor position signal (P ₁ ) and/or the second rotor position signal (P ₂ ) is generated by a magnetoresistive rotor position sensor (16, 17), a Hall sensor, an eddy current sensor, an optical incremental encoder, a resolver and/or a hardware demodulator is provided. Method according to one of the preceding claims, characterized in that the complex angle function (K ₁ ) for the first rotor position sensor (16) of the form $$\begin{array}{c}{K}_1\left(t\right)={\displaystyle \sum _i^{\infty }{A}_{c\mathrm{,1,}i}\left(t\right)\cdot \text{cos}\left(p_1{\mathrm{\varphi }}_i\left(t\right)+\Delta {\mathrm{\varphi }}_{\mathrm{1,}i}\right)+{\text{O}}_{c\mathrm{,1}}\left(\text{t}\right)}+\\ j\cdot \left[A_{s\mathrm{,1,}i}\left(t\right)\cdot \text{sin}\left(p_1{\mathrm{\varphi }}_i\left(t\right)\right)+{\text{O}}_{s\mathrm{,1}}\left(\text{t}\right)\right]\end{array}$$

and for the second rotor position sensor (17) of the mold $$\begin{array}{c}{K}_2\left(t\right)={\displaystyle \sum _i^{\infty }{A}_{c\mathrm{,2,}i}\left(t\right)\cdot \text{cos}\left(p_2\mathrm{}{\mathrm{\varphi }}_2\mathrm{}\left(t\right)+\Delta {\mathrm{\varphi }}_{\mathrm{2,}i}+{\mathrm{\varphi }}_{1.2}\right)+{\text{O}}_{c\mathrm{,2}}\left(\text{t}\right)}+\\ j\cdot \left[A_{s\mathrm{,2,}i}\cdot \text{sin}\left(p_2{\mathrm{\varphi }}_i\left(t\right)+{\mathrm{\varphi }}_{1.2}\right)+{\text{O}}_{s\mathrm{,2}}\left(\text{t}\right)\right]\end{array}$$

where the indices 1 and 2 stand for the first and the second rotor position sensor (16, 17), j is the imaginary unit, p ₁ , p ₂ are the pole pair numbers of the first and second rotor position sensor (16, 17), φ _i ( t) = ω _0i · t + δ _i the time-dependent angle of the rotor with a phase shift δ _i between different fundamental and harmonics, Δϕ _i the deviation of the axis angle (α _i ) of the two axes (30, 32) from 90°, ϕ _1,2 the phase offset of the rotor position signals (P ₁ , P ₂ ), A _c,1/2,i (t) and A _s,1/2,i (t) the amplitudes of the fundamental (j=1) and harmonics (i > 1) of the real and imaginary parts of the corresponding trigonometric function (K ₁ , K ₂ ) and O _c,i/2 (t) and O _s,1/2 (t) offsets of the real and imaginary parts. Method according to one of the preceding claims, characterized in that the filter module (36) applies a filter (42) based on a complex phase-locked loop to the complex trigonometric functions (K ₁ , K ₂ ). procedure after claim 9 , characterized in that the filter (42) is stored as a transfer function in the filter module (36). Method according to one of the preceding claims, characterized in that the controller (14) receives a third rotor position signal from a third rotor position sensor, the third rotor position signal being a position value along the first of two axes (30, 32) in the plane of rotation of the rotor (20). and a second position value along the second of the two axes (30, 32), and wherein the controller (14) determines the angle (φ) of the rotor (20) and/or the angular velocity (ω) based on the three rotor position signals. Controller (14) for a motor vehicle, wherein the controller (14) is designed to carry out a method according to one of the preceding claims. Motor vehicle with an electric motor (12) and a controller (14). claim 12 .

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