Method and device for calibrating a regulator of an electric machine

Abstract

Method (400) for calibrating a regulator of an electric machine (120). The method comprises the steps of predetermining (410) a first signal (S_1) for generating a sinusoidal phase current for energizing a winding of the electric machine (120), superimposing (420) the first signal (S_1) with a test signal (S_Test_i) for generating a harmonic oscillation with a predetermined excitation amplitude and / or a phase position relative to the phase current, the harmonic oscillation being superimposed on the phase current, detecting (430) a response signal (S_Antw_i) resulting from the superposition of the phase current and the harmonic oscillation by means of a sensor (130), determining (450) a calibration signal (S_kal) for generating a harmonic oscillation with a predetermined excitation amplitude and a phase position relative to the phase current based on a determined minimum value of a response surface (A_Antw), and operating (460) the regulator (110) of the electric machine (120) based on the determined minimum value.

Description

Technical Field

[0001] The invention relates to a method and a device for calibrating a regulator of an electric machine. The invention also relates to an electric drive system with a corresponding device and a vehicle with an electric drive system as well as a computer program and a computer-readable storage medium. Background Art

[0002] In order to generate the desired torque by means of a suitable combination of direct torque and reluctance torque, an induction motor, in particular a permanent magnet synchronous motor (PSM) with embedded magnets, is controlled. In the case of a field-oriented controller, the direct torque and the reluctance torque are selected by means of a corresponding selection of the d and q current operating points (id, iq) in the rotor-fixed coordinate system. During operation, the motor, in addition to outputting a uniform average torque, also generates harmonics of the torque, which are formed, for example, due to non-ideal sinusoidal magnetic fields, winding arrangements, slots, tooth shapes, saturation effects and / or other effects.

[0003] Such effects lead to force waves between the rotor and the stator, which act on the stator teeth as tangential and radial tooth forces in the case of characteristic orders and become perceptible from the stator teeth as vibrations in the machine, vibrations of the machine housing and coupling elements and therefore as structure-borne and airborne sound or surface vibrations due to the mechanical transmission behavior of the motor. Such vibrations can be reduced or amplified by means of current harmonics that are applied in a targeted manner in addition to the actual pre-set phase current, and the current harmonics have a matching order. It is known that, for example, the parameters of the current harmonics to be applied are read out from a characteristic curve family that depends on, for example, the torque to be set or the operating point, and the corresponding current harmonics are superimposed on the actual phase current during motor operation. If, for example due to sample tolerances, there is no sufficiently accurate model-based description available for the relevant effects of the motor - from which the parameters can be determined in a simulated manner, the parameters must be determined in another way. In order to determine the parameters of the current harmonics, a large amount of application and calibration work is required on a test bench. Here, for example, surface acceleration / velocity, sound radiation in the motor environment or torque fluctuations or torque oscillations are preferably determined. With the aid of suitable measurement signals, for example, the minimum value of a single-parameter system or the optimum value of a multi-parameter system with competing objectives is preferably determined iteratively to determine the parameters of the current harmonics to be applied. If a torque sensor is available in the drive, calibration can also be performed based on this sensor signal, wherein the sensitivity of the sensor must be correspondingly high in order to obtain low torque ripples compared to the useful torque by means of measurement technology. Torque sensors are expensive and are therefore not available as standard in many applications.

[0004] Therefore, there is a need for alternative methods and apparatus for calibrating a regulator of an electric machine. Summary of the invention

[0005] A method for calibrating a regulator of an electric motor is provided, comprising the following steps:

[0006] predefining a first signal for generating a sinusoidal phase current for energizing at least one winding of the electric machine,

[0007] superimposing the first signal with a test signal to generate at least one harmonic oscillation having a predetermined excitation amplitude and / or a phase position relative to a phase current, the harmonic oscillation being superimposed on the phase current,

[0008] detecting, by means of a sensor, a response signal resulting from the superposition of the phase current and the harmonic oscillation, in particular a response amplitude of the response signal,

[0009] Repeating the two preceding steps of "superposition" and "detection" multiple times with different test signals to generate further harmonic oscillations with a predeterminable excitation amplitude and / or a phase position relative to the phase current, said further harmonic oscillations being superimposed on the phase current,

[0010] determining a minimum value of a response surface which is generated from a response signal resulting from a harmonic oscillation generated by means of the test signal over a preferably predeterminable excitation amplitude range and phase position region,

[0011] determining, as a function of the determined minimum value, a calibration signal for generating a harmonic oscillation having a predetermined excitation amplitude and a phase position relative to the phase current, for which calibration signal preferably results in a response signal having a minimum response amplitude,

[0012] A controller of the electric machine is operated; the first signal is predefined to generate a sinusoidal phase current for energizing windings of the electric machine, and the first signal is superimposed with a determined calibration signal for generating harmonic oscillations.

[0013] It is known to operate electric machines with the aid of field-oriented control. In this process, the AC variables of the phase currents are each transferred into a coordinate system that rotates at the frequency of the AC variables. In this rotating coordinate system, DC variables are then generated from the AC variables in the static operation of the electric machine, to which all common control technology methods can be applied. Due to the multi-phase, phase-shifted AC currents applied to the stator, a rotating magnetic field is generated during the operation of the electric machine, which is preferably described as a rotating linkage flux in a coordinate system fixed to the stator or a time-constant linkage flux in a rotating (d / q) coordinate system fixed to the rotor or in a field-oriented system.

[0014] The controller of the electric machine preferably predetermines a signal for generating a sinusoidal phase current as a function of a predeterminable torque value. The sinusoidal phase current preferably flows through the stator and therefore corresponds to the stator current. In a rotating coordinate system, i.e., a d / q coordinate system or a field-oriented system, which rotates synchronously with the rotor flux or the permanent magnet flux in the PSM and whose d-axis points in the direction of the rotor flux, the stator current is represented as a stator current phasor or stator current vector, which is characterized by its length and its direction. The current phasor rotates synchronously with the rotating stator flux or rotor flux of the electric machine. In the d / q coordinate system, the current phasor can be represented by means of two mutually perpendicular components Id and Iq corresponding to its length and its direction, which are DC variables in the static state. The first signal for generating the sinusoidal phase current is superimposed with a test signal to generate a harmonic oscillation with a predetermined amplitude and / or phase position relative to the sinusoidal phase current, which is superimposed with the sinusoidal phase current. The predetermined amplitude thus generated is referred to as the excitation amplitude. Preferably, the harmonic oscillation is a harmonic of a predetermined order relative to the sinusoidal phase current, which is superimposed on the sinusoidal phase current. This superposition leads to an oscillation of the output torque and / or a change in the force acting between the rotor and the stator of the connected motor. Due to the mechanical coupling of the motor to the housing, this oscillation of the torque or force leads to mechanical and / or acoustic vibrations of the housing and components connected to the housing. The entire transmission path is from the superimposed harmonic current oscillations via the oscillations of the electromagnetic forces and torque to the mechanical vibrations or noise excitations of the connected motor and / or power electronics, which can be measured with suitable sensors, for example acoustically. This vibration resulting from the superposition of the phase current and the harmonic oscillations is detected as a response signal by means of a sensor. Preferably, the harmonic oscillation of the torque is detected as a response signal.

[0015] This superposition is repeated several times, preferably at least three times, with different, preferably predetermined test signals to generate further harmonic oscillations with a predeterminable excitation amplitude and / or phase position relative to the phase current. Preferably, a first test signal S_Test_1 is predetermined to generate harmonic oscillations with a predetermined excitation amplitude S_Test_1_A=0 and any phase position relative to the phase current. Furthermore, preferably three further test signals S_Test_2, S_Test_3, S_Test_4 are predetermined to generate harmonic oscillations with a common, fixed, predetermined excitation amplitude S_Test_2,3,4_A>0 and a phase position (e.g. 0, 120°, 240° or 60°, 180°, 300°) uniformly distributed over 360° relative to the phase current. A characteristic, well-defined, multiply curved response surface is generated by means of at least four different response signals detected accordingly. In order to generate further support points of the response surface, further test signals may preferably be predefined to generate further harmonic oscillations with predefined and / or different excitation amplitudes and / or phase positions relative to the phase currents. Figure 3 As shown in , when observed at different excitation amplitudes of the test signals and the phase positions of these test signals, the response surface generated by the response signal, in particular the amplitude of the response signal or the response amplitude, has a characteristic shape / topology. The response surface preferably extends over a phase position of 0° to 360° and an excitation amplitude of the test signal with negative and / or positive magnitude. The response surface contains two minimum values ​​in the display of phase positions 0 to 360° and positive and negative excitation amplitudes, one in the region where the excitation amplitude of the harmonic oscillation generated by means of the test signal is >0, and one in the region where the excitation amplitude of the harmonic oscillation generated by means of the test signal is <0. The first minimum is characterized by the first minimum phase position and the positive first minimum amplitude. The second minimum is characterized by the second minimum phase position and the negative second minimum amplitude. The first minimum phase position is offset by 180° from the second minimum phase position.

[0016] The superposition of the first signal with the second signal, preferably a test signal or a calibration signal, which is used to generate harmonic oscillations with a predetermined excitation amplitude and a phase position relative to the phase current, which excitation amplitude and phase position correspond to the excitation amplitude and phase position of the determined minimum values, i.e. harmonic oscillations with a first or second minimum phase position and a corresponding first or second minimum amplitude, leads to minimization of the mechanical vibrations or noise excitation generated on the side of the connected drive system, which includes a connected electric machine, power electronics and / or a drive train.

[0017] Whether considering the unknown harmonic oscillation directly or the influence of linear or nearly linear transmission paths on measurable parameters, the topological structure of the response surface maintains its characteristics.

[0018] In addition to other mathematical methods for determining the position of the minimum of such a response surface from the determined response signal, the following procedure is preferably performed:

[0019] According to the course of the response amplitude of the response signal resulting from the test signal for generating harmonic oscillations with a common, fixed, predetermined excitation amplitude >> 0, the phase position relative to the phase current changes sinusoidally for the region with excitation amplitude > 0.

[0020] For the region of excitation amplitude <0, the characteristics of the response surface result in a sinusoidal variation with a 180° phase shift in its phase position relative to the phase current for the variation of the response amplitude of the response signal resulting from the test signal for generating harmonic oscillations with an opposite or negative, common, fixed, predetermined excitation amplitude. The positions of the high and low points of these variations correspond to the positions of the two minima of the response surface in terms of the phase position relative to the phase current. Another characteristic of the response surface is that the (positive) gradient of the response surface is approximately constant in the negative and positive direction with increasing absolute value of the excitation amplitude of the harmonic oscillation generated by means of the test signal.

[0021] The first step of determining the position of the minimum uses the response signal S_Antw_2,3,4 resulting from a test signal for generating a harmonic oscillation with a common, fixed, predetermined excitation amplitude>>0 to determine the 0th and 1st order Fourier coefficients of the behavior of the response surface for the associated excitation amplitude. From the Fourier coefficients, the minimum and maximum values ​​of the sinusoidal variation of the response amplitude are determined, preferably the response amplitude and the phase position of the minimum and maximum values. This is preferably performed for the region with the excitation amplitude>0. In the second step, the other characteristic of the response surface is used, namely that the absolute value of the gradient of the response surface is approximately constant in the positive and negative direction with increasing absolute value of the excitation amplitude>>0 to be generated by means of the test signal. For example, at the phase position of the determined maximum value of the sinusoidal variation, the associated slope for the region with the excitation amplitude>0 is determined from the height of the response amplitude of the response signal S_Antw_1 resulting from the first test signal and the height of the determined maximum response amplitude of the sinusoidal variation. The value or height of the response signal or the response amplitude, which results from the first test signal for generating harmonic oscillations with a predetermined excitation amplitude S_Test_1_A=0, is constant over a phase position from 0 to 360°, since the superposition of the first signal with the test signal for generating harmonic oscillations with a predetermined excitation amplitude=0 has no effect on the response amplitude generated with the aid of the first signal, regardless of the phase position to be generated with the aid of the test signal. With the aid of the slope determined in this way and, for example, the minimum value of the sinusoidal course in the region of excitation amplitude <0 and the maximum value of the sinusoidal course in the region of excitation amplitude >0, two straight lines can be described. The first straight line G1 has the determined slope and passes through the point of the height of the response amplitude resulting from the first test signal at the phase position of the determined maximum value of the sinusoidal course, which results from the test signal for generating harmonic oscillations with a common, fixed, predetermined excitation amplitude >> 0, and through the point of the maximum height of the sinusoidal course.

[0022] The second straight line G2 has a negative determined slope and passes through the point of the minimum height of the sinusoidal variation process at the phase position of the determined maximum of the sinusoidal variation process, which is generated for the region of the excitation amplitude <0 of the response surface. Preferably, two further straight lines G1' and G2' can be constructed, whose phase positions are offset by 180° relative to the straight lines G1 and G2, wherein G1' intersects with the point of the determined height of the minimum of the response amplitude of the sinusoidal variation process at the phase position of the minimum determined by the sinusoidal variation process in the region of the excitation amplitude>0. The two straight lines G1 and G2 intersect at the first minimum, the position of which is described by means of the excitation amplitude and the phase position with respect to the response surface. For the first minimum, a first minimum phase position is generated, and a first (negative) minimum amplitude is generated as the excitation amplitude. The two straight lines G1' and G2' intersect at the second minimum, the position of which is described by means of the excitation amplitude and the phase position with respect to the response surface. For the second minimum, a second minimum phase position is generated, and a second (positive) minimum amplitude is generated as the excitation amplitude. The first minimum phase position is offset from the second minimum phase position by 180°. The absolute value of the first minimum amplitude corresponds to the absolute value of the second minimum amplitude, wherein the sign of one minimum amplitude is negative and the sign of the other minimum amplitude is positive.

[0023] With the aid of the parameters determined in this way - the minimum amplitude and the minimum phase position of the minimum value of the response surface - it is possible, on the one hand, to predetermine the parameters of a calibration signal for generating a harmonic oscillation with the minimum amplitude as the excitation amplitude and the minimum phase position as the phase position, which calibration signal leads to minimization of the mechanical vibrations when superimposed on the first signal.

[0024] On the other hand, a well-defined response surface can be constructed based on the slopes and minimum values ​​determined from the response amplitudes of the test signal. Thus, the parameters of the harmonic oscillation to be generated with the aid of the calibration signal can be read out and predefined from the well-defined response surface, which, when superimposed with the first signal, causes a correspondingly determined response signal or response amplitude at a point on the response surface, or correspondingly causes mechanical vibrations and thus sounds or noise. Thus, based on the response surface, a predefinable operating point can be set in a targeted manner by predefining a calibration signal to generate a harmonic oscillation with the excitation amplitude and phase position of the corresponding point of the response surface as parameters.

[0025] In order to determine the calibration signal for generating harmonic oscillations with the excitation amplitude and phase position as parameters, the parameters of the excitation amplitude and phase position to be generated are predefined as a function of one of the specific minimum values ​​of the resulting response surface. Preferably, the minimum amplitude and the minimum phase of the minimum value are used as parameters. When the first signal for generating a sinusoidal phase current is superimposed with the preferred calibration signal, the generated torque oscillations are minimal. Subsequently, the regulator of the electric machine is operated by superimposing the first signal and the calibration signal in order to generate sinusoidal phase currents for energizing the windings of the electric machine and to generate harmonic oscillations.

[0026] Advantageously, a method is provided, with which a regulator of an electric machine is calibrated by means of a predefined number of harmonic excitations or test signals. From the correlation of the detected response signals, a predeterminable optimal value of the torque oscillation and / or the force acting between the rotor and the stator is constructed, preferably by forward calculation. The (time) expenditure of the measurement technology and the expenditure of the calculation technology are known before the calibration and can be planned accordingly, for example for operating states with high external noise, so that during the calibration, noise that causes interference to the driver of the electric drive vehicle or the operator of the connected electric machine is masked. Repeated measurements, i.e., the detection of different response signals, can be carried out independently of each other in time and can therefore be performed without interruption, because direct feedback is not used. The expected influence on the torque oscillation, the force between the stator and the rotor and / or the oscillation during the DC link voltage change, the expected influence of the harmonic excitation or test signal of the previously defined number on the drive can be estimated in advance, so that, for example, in the case of use in a vehicle, a favorable operating point can be selected for the method. During this method, vibrations in the drive train or onboard power supply network vibrations are preferably minimized. Preferably, the method is provided for an integrated electric axle, which consists of an induction motor and a power electronics unit mechanically mounted (preferably mechanically strong or firmly coupled) or integrated to the motor. The method enables the method to be performed for each individual motor. The method can be performed at any time at the end of a production line and / or during the life cycle of an electric drive, even during normal driving operation. The drive component (e.g. an electric axle) preferably includes a sensor and the method. The possibility of running the method during the start of operation, during an inspection at the end of the belt or during driving operation is provided. Thereby, calibration parameters can be determined and readjusted or relearned in an example-specific, temperature-dependent and / or aging-dependent manner. A method for providing a self-learning / self-calibrating regulator for an electric drive is created. A self-calibration that minimizes torque oscillations can be achieved, which is performed independently of a test bench and an external measuring sensor system.

[0027] In another embodiment of the invention, the method includes reading out an operating point of the electric machine, the inverter and / or the battery and performing the method as a function of the detected operating point.

[0028] A method is provided which makes it possible to take into account the operating point of an electric machine, an inverter and / or a battery. Preferably, the operating point of a driven transmission or a drive train is taken into account. The operating point of an electric machine, an inverter, a battery, a driven transmission or a drive train can be, for example, the torque, speed, current, voltage, temperature or usage time required by the corresponding component. Depending on the operating point, a predeterminable test signal adapted to the operating point can be superimposed on the first signal.

[0029] Advantageously, a method is provided which is able to take into account the operating point of the electric machine.

[0030] Furthermore, the invention relates to a computer program comprising instructions which, when executed by a computer, cause the computer to carry out the steps of the method described thus far.

[0031] Furthermore, the invention relates to a computer-readable storage medium comprising instructions which, when executed by a computer, cause the computer to perform the steps of the method described hitherto.

[0032] The invention also relates to a device for calibrating a regulator of an electric machine. The device comprises a preferably mechanical sensor. The device also comprises a circuit carrier, wherein the circuit carrier has a test signal generator and a computing unit. The device is configured to carry out the steps of the described method.

[0033] Alternatively or additionally, an ammeter or voltmeter can also be used, which is arranged, for example, on the DC voltage side of an inverter connected to the electric machine. The ammeter or voltmeter detects the resulting oscillations in the current / voltage as the resulting response signal. Oscillations or stress fluctuations can be reduced by means of this method.

[0034] Advantageously, a device for calibrating a regulator of an electric machine is provided. The device comprises a preferably mechanical sensor for detecting a response signal resulting from the superposition of a first signal and a test signal. The device also comprises a test signal generator for predetermining the test signal and a computing unit for executing the method.

[0035] In another embodiment of the invention, the sensor is mechanically fixedly or substantially rigidly connected to the electric motor. Alternatively, the sensor is fixedly mounted on the circuit carrier and the circuit carrier is fixedly integrated on or in the electric motor.

[0036] For high-resolution and undisturbed detection of the response signal, a mechanically fixed connection to the motor or via a circuit carrier attached to or in the motor is provided. Alternatively, this can of course also be performed using sensors or power electronics external to the device, such as microphones on or next to the motor, or by means of structure-borne sound sensors, such as acceleration sensors designed to be mounted on a surface, preferably the surface of the motor or a control unit or an inverter.

[0037] Advantageously, a location is provided for fixing the sensor for good signal transmission.

[0038] In a further embodiment of the invention, the mechanical sensor is a microphone, an acceleration sensor or a structure-borne sound sensor or a rotational speed sensor, a torque sensor or a torque measuring shaft.

[0039] Advantageously, a sensor is provided for detecting a response signal resulting from torque oscillations or force oscillations between the rotor and the stator. The torque oscillations or force oscillations can be detected acoustically by means of acceleration measurement (preferably on a mechanically rigid unit with the electric machine) or by means of structure-borne sound. Likewise, a change in the speed of the electric machine results from the torque oscillations, so that the response signal can also be detected by means of a speed sensor.

[0040] The invention also relates to an electric drive system having an electric machine and the described device. Such an electric drive system is used, for example, to drive an electric vehicle. With the aid of the method and the device, an optimized operation of the drive train can be achieved.

[0041] Furthermore, the invention relates to a vehicle having the described drive system.Therefore, advantageously a vehicle is provided which comprises a device which can be used to calibrate a regulator of an electric machine.

[0042] It will be appreciated that the features, characteristics and advantages of the method according to the invention are correspondingly applicable or applicable to the device or the drive system and the vehicle, and vice versa.

[0043] Other features and advantages of the embodiments of the present invention are apparent from the following description with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The invention will be explained in more detail below based on some drawings, for which:

[0045] Figure 1 A schematic diagram of a device for calibrating a regulator of an electric motor is shown.

[0046] Figure 2 A schematic control structure of a method for calibrating a controller of an electric machine is shown.

[0047] Figure 3A schematic response surface of the resulting response signal is shown.

[0048] Figure 4 A schematically illustrated vehicle with a drive train is shown.

[0049] Figure 5 A schematically illustrated flow chart of a method for calibrating a controller of an electric machine is shown. DETAILED DESCRIPTION

[0050] Figure 1 A device 100 is shown for calibrating a regulator 110 of an electric machine 120. The device comprises a sensor 130, preferably a mechanical sensor having a mechanically rigid or secure direct or indirect connection to the electric machine 120. The device also comprises a circuit carrier 150, wherein the circuit carrier has a test signal generator 160 and a calculation unit 170. The regulator 110 is preferably integrated in an inverter 140, wherein the inverter comprises power electronics 145, preferably a B6 bridge, for feeding the connectable machine 120 from a battery 155. In addition, in Figure 1 1 shows an electric drive system 200 having a device 100 and an electric machine 120. According to a first test signal S_1 and a plurality of test signals S_Test_i, a power electronics 145 of an inverter 140 is controlled to calibrate a regulator 110 of the electric machine 120. The response signal S_Antw_i is detected by means of a sensor 130. After the calibration signal S_kal is determined, the power electronics 145 of the inverter 140 is controlled to operate the regulator 110 of the electric machine 120 according to the first test signal S_1 and the calibration signal S_kal.

[0051] Figure 2A schematic control structure 500 of a method for calibrating a regulator 110 of an electric motor 120 is shown. A signal generator 510 outputs a first signal S_1. The first signal S_1 is superimposed with a test signal S_Test_i of a test signal generator 160 by means of an adder 540 for calibrating the regulator 110 of the electric motor 120. The electric motor 120 is controlled by a control path 520 according to the superimposed signal. The superimposed signal generates a torque with oscillations. These oscillations are detected by means of a sensor 130 and forwarded as a response signal S_Antw_i to a calculation unit 170 for evaluation. The calculation unit 170 also receives the first signal S_1 and the test signal S_Test_i for evaluation. The evaluation includes determining the minimum value of the generated response surface A_Antw from the response signal S_Antw_i resulting from the harmonic oscillation generated by means of the test signal S_Test_i. The calculation unit 170 determines the minimum of the response surface A_Antw and determines, as a function of the parameters of the minimum, a calibration signal S_kal for generating a harmonic oscillation having a predetermined excitation amplitude and a phase position relative to the phase current. The calibration signal is selected by means of a switch 550 and superimposed with the first signal S_1 by means of an adder 540 for normal operation of the regulator 110 of the motor 120. The test signal S_Test_i or the calibration signal S_kal for superposition can be selected by means of the switch 550, depending on whether the regulator 110 is calibrated or operated normally for operating the motor 120.

[0052] Figure 3 A schematic response surface A_Antw is shown, which is generated by the response signal S_Antw_i obtained as a result of the harmonic oscillation generated with the aid of the test signal S_Test_i. The magnitude of the response amplitude S_Antw_i_A of the resulting response signal S_Antw_i is plotted in the z direction. The phase position S_Test_i_Phi of the harmonic oscillation to be generated with the test signal S_Test_i is plotted in the y direction. The magnitude of the excitation amplitude S_Test_i_A of the harmonic oscillation to be generated with the test signal S_Test_i is plotted in the x direction. Four positions of the phase position, the excitation amplitude and the response signal corresponding to the harmonic oscillation generated with the aid of the test signal are plotted by way of example, from which the response surface A_Antw is generated, as described above. The response surface is preferably determined according to the determined minimum value within a predeterminable range of the phase position (e.g. 0 to 360 degrees) and a predeterminable range of the excitation amplitude (e.g. from -15 to +15). In addition, the minimum value of the response surface determined as described above can be determined with the aid of Figure 3The variation of the contour lines and the response surface in FIG. 1 is shown in FIG. 2 . Based on at least one minimum phase position and at least one minimum amplitude, the excitation amplitude and phase position of the harmonic oscillation to be generated by means of the calibration signal are determined and predetermined as parameters.

[0053] Figure 4 A schematically illustrated vehicle 300 is shown with an electric drive system 200. The drive system 200 comprises an apparatus 100 for calibrating a regulator 110 of an electric machine 120 in an inverter 140 and an electric machine 210. The electric drive system preferably comprises a battery 150.

[0054] Figure 5 A schematic sequence of a method 400 for calibrating a regulator of an electric machine 120 is shown. The method starts with step 405. Preferably, an operating point of the electric machine 120, the inverter 140 and / or the battery 150 is subsequently read 407 and the method is carried out as a function of the detected operating point.

[0055] Other methods 400 include the steps of:

[0056] predetermining 410 a first signal S_1 for generating a sinusoidal phase current for energizing a winding of electric motor 120 ,

[0057] superimposing 420 the first signal S_1 with the test signal S_Test_i to generate at least one harmonic oscillation, preferably a harmonic of a predeterminable order, with a predetermined excitation amplitude and / or a phase position relative to the phase current, which is superimposed on the phase current,

[0058] Detecting 430 a response signal S_Antw_i resulting from the superposition of the phase current and the harmonic oscillation by means of the sensor 130;

[0059] Repeating the two previous steps “superposition” 420 and “detection” 430 several times using different test signals S_Test_i in order to generate further harmonic oscillations with predeterminable and / or different excitation amplitudes and / or phase positions relative to the phase currents, said further harmonic oscillations being superimposed on the phase currents,

[0060] determining 440 the minimum value of the response surface A_Antw of the multiple bends generated from the response signal S_Antw_i resulting from the harmonic oscillation generated by means of the test signal S_Test_i,

[0061] determining 450 a calibration signal S_kal according to the determined minimum value of the response surface A_Antw to generate a harmonic oscillation with a predetermined excitation amplitude and phase position relative to the phase current, preferably resulting in a response signal with a minimum response amplitude for the minimum value,

[0062] The controller 110 of the electric motor 120 is operated 460 , wherein a first signal S_1 is predetermined to generate a sinusoidal phase current for energizing the windings of the electric motor 120 , and the first signal S_1 is superimposed with a calibration signal S_kal to generate a harmonic oscillation having a predetermined excitation amplitude and a phase position relative to the phase current. The method ends with step 470 .

Claims

1. A method (400) for calibrating a regulator (110) of a motor (120), comprising the steps of: presetting a first signal (S_1) for generating a sinusoidal phase current for energizing a winding of an electric machine (120), superimposing the first signal (S_1) with a test signal (S_Test_i) to generate at least one harmonic oscillation having a predetermined excitation amplitude and / or phase position relative to a phase current, the harmonic oscillation being superimposed on the phase current, By means of a sensor (130), a response signal (S_Antw_i) obtained as a result of the superposition of the phase current and the harmonic oscillation is detected, Repeating the two previous steps "superposition" and "detection" several times using different test signals (S_Test_i) in order to generate further harmonic oscillations with a predeterminable excitation amplitude and / or phase position relative to the phase current, said further harmonic oscillations being superimposed on said phase current, determining a minimum value of a response surface (A_Antw) of multiple bends, said response surface being generated from a response signal (S_Antw_i) resulting from a harmonic oscillation generated by means of said test signal (S_Test_i), determining a calibration signal (S_kal) according to the determined minimum value to generate a harmonic oscillation having a predetermined excitation amplitude and a phase position relative to the phase current, A controller (110) is operated for operating the electric machine (120); the first signal (S_1) is predefined to generate a sinusoidal phase current for energizing a winding of the electric machine (120), and the first signal (S_1) is superimposed with a determined calibration signal (S_kal) for generating the harmonic oscillation.

2. The method (400) according to claim 1, further comprising the following steps: reading the operating point of the motor (120), inverter (140) and / or battery (150), and The method is performed as a function of the detected operating point.

3. A computer program product, comprising a computer program having instructions, which, when the computer program is executed by a computer, cause the computer to perform the steps of the method (400) according to any one of claims 1 to 2.

4. A computer-readable storage medium comprising instructions which, when executed by a computer, cause the computer to perform the steps of the method (400) according to any one of claims 1 to 2.

5. A device (100) for calibrating a regulator (110) of an electric motor (120), Having a sensor (130), Having a circuit carrier (150), The circuit carrier comprises a test signal generator (160) and a computing unit (170), The device is configured to perform the steps of the method according to any one of claims 1 to 2.

6. The device (100) according to claim 5, The sensor (130) is mechanically firmly connected to the motor (120), or the sensor (130) is firmly mounted on the circuit carrier (150) and the circuit carrier (150) is firmly integrated on or in the motor (120). 7 . The device ( 100 ) according to claim 6 , wherein the sensor ( 130 ) is a microphone, an acceleration sensor or a structure-borne sound sensor or a rotational speed sensor.

8. An electric drive system (200) comprising an electric machine (120) and a device (100) according to any one of claims 5 to 7.

9. A vehicle (300) having the electric drive system (200) according to claim 8.

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