Method for operating an electric machine

Abstract

The invention relates to a method for operating an electrical machine, the electrical machine having a rotor and a stator, wherein the stator has a stator winding, the stator winding having a first phase assembly and a second phase assembly, and wherein the phase assemblies each have the same number of phases, wherein at least one first actual phase current of a first phase of the first phase assembly is detected, and wherein a second actual phase current of a second phase of the first phase assembly is detected. It is provided here that a first rated phase current of a first phase of the second phase assembly or a rated phase current of a third phase of the first phase assembly is determined from the following variables: the first actual phase current; the second actual phase current; a first angle difference between the first phase of the first phase assembly and the first phase of the second phase assembly or the third phase of the first phase assembly; and a second angle difference between the second phase of the first phase assembly and the first phase of the second phase assembly or the third phase of the first phase assembly.

Description

Technical Field

[0001] This invention relates to a method for operating an electric motor. Furthermore, this invention relates to a controller for performing the method and a motor having such a controller. Background Technology

[0002] An electric motor is known from the prior art, for example from DE 10 2007 005 742 A1.

[0003] To operate the motor, for example in the automotive field, high safety requirements, such as those according to ISO 26262, are required. For drive units with safety classifications, the generated torque is typically dominated by a safe load. Typically, for cost reasons, torque is not measured by torque sensors, but rather by measuring phase current using machine equations. To meet safety requirements, reliability verification techniques may be required to ensure the calculated signals and their input parameters are adequately verified.

[0004] Here, confidence verification can only be performed in the sense of ISO 26262 if it is ensured that it is sufficiently independent of the measurement parameters and confidence verification algorithm, so as to be able to exclude so-called common-cause faults.

[0005] This might require the use of sensors that can measure at any point in time. This could result in high costs. The reliability check performed by comparing the measured phase current with a preset current used to energize that phase could be costly, as the motor's operating point must be known.

[0006] Other applications, such as those not critical to safety, are also possible. In motors with multiple independent subsystems or phase assemblies (e.g., two three-phase assemblies) in the stator (with fixed torsional angles relative to each other), each subsystem or phase assembly is equipped with its own control electronics. For each phase assembly, energizing a single phase is achieved independently of the others, using a measurement of the corresponding phase current as the actual value for regulation. This requires high-cost current sensors. Alternatively, while current sensors can be eliminated, regulation becomes inaccurate or impossible, and the motor cannot be operated particularly efficiently. Summary of the Invention

[0007] This invention is based on the understanding that, due to limited space and ongoing cost pressures, motors and / or electric drive devices should be smaller and more advantageous while maintaining the same power and high efficiency, and safe operation is also required.

[0008] Therefore, there is a need for a method for operating a motor that ensures safe operation, where torque sensors can be eliminated. Simultaneously, it may be necessary to use cost-effective sensors to measure the current in individual phases, which may not be available for measurement at all times (e.g., of three sensors on three phases, only two sensors can be used simultaneously for measurement). Finally, there may be a need to ensure motor operation and / or to perform reliability checks solely based on the measured and calculated current (without comparison to the preset phase current) without knowledge of the current preset by the control electronics. There may also be a need to enable the diagnosis of, for example, winding short circuits, winding open circuits, or short circuits relative to the housing in subsystems or phase assemblies using this method.

[0009] Alternatively or additionally, there is a need to design the method in such a way that simple and cost-effective control of the phase current of the second phase component can be achieved in a motor with multiple phase components in the stator. For this purpose, the measurement of the phase current in the second phase component (as the actual value used for control) should be eliminated as much as possible. Thus, other phase components can also be effectively energized based on the operation of the first phase component and the measurement of its phase current. This should also apply, for example, to situations where different high partial torques are required by means of different phase components, which then derive the total torque. Simultaneously, it is desirable to place only a current measuring sensor in one of the two phase components, preferably, even exactly two current measuring sensors, in order to save cost and space in this way.

[0010] In addition, there may be a need for a controller that can implement this method, and there may be a need for a motor with such a controller.

[0011] Advantages of the present invention

[0012] This need can be met by the subject matter of this invention. Advantageous embodiments of the invention are described below.

[0013] According to a first aspect of the present invention, a method for operating an electric motor is provided.

[0014] This method can be used, for example, for a motor used to operate a motor vehicle, but is not limited to such a motor. The motor has a rotor and a stator, wherein the rotor is arranged anti-torsional on a shaft rotatably supported in a housing, wherein the stator is fixedly arranged to the housing and has a stator winding having a first phase assembly and a second phase assembly electrically separated from the first phase assembly, wherein each phase assembly has the same number of phases, wherein the same phase of the first phase assembly is arranged to be twisted relative to the same phase of the second phase assembly by a torsion angle, wherein the phases of the first phase assembly are controlled according to the rotation angle of the rotor, wherein the phases of the second phase assembly are phase-shifted relative to the phases of the first phase assembly according to the rotation angle, wherein at least one first actual phase current of the first phase of the first phase assembly is detected, and wherein a second actual phase current of the second phase of the first phase assembly is detected. Herein, it is specified according to the following parameters:

[0015] -- The first actual phase current of the first phase of the first phase component;

[0016] -- The second actual phase current of the second phase of the first phase component.

[0017] -- The first angle difference (Differenzwinkel) between the first phase of the first phase component whose first actual phase current has been detected and the first phase of the second phase component whose first rated phase current will be measured.

[0018] or

[0019] The first angle difference between the first phase of the first phase component whose first actual phase current has been detected and the third phase of the first phase component whose rated phase current will be measured.

[0020] -- The second angle difference between the second phase of the first phase component whose second actual phase current has been detected and the first phase of the second phase component whose first rated phase current will be measured.

[0021] or

[0022] The second angle difference between the second phase of the first phase component whose second actual phase current has been detected and the third phase of the first phase component whose rated phase current will be measured.

[0023] To determine the first rated phase current of the first phase of the second phase component or the rated phase current of the third phase of the first phase component.

[0024] Therefore, it is advantageous to determine each phase current of the second phase component in a simple manner by detecting or measuring only the two actual phase currents of the first phase component. If, for example, there exists a motor with two three-phase phase components, namely phases A1, B1, and C1 for the first phase component and phases A2, B2, and C2 for the second phase component, then, for example, the rated phase current as the first rated phase current can be determined for each of phases A2, B2, and C2 by detecting the actual phase currents of phases A1 and B1 (as the first and second actual phase currents). Similarly, detecting the actual phase currents of phases A1 and C1 or B1 and C1 is also sufficient for this purpose.

[0025] The same consideration applies to an exemplary motor having two five-phase phase assemblies or subsystems in the stator, namely phases A1, B1, C1, D1, and F1 in the first phase assembly and phases A2, B2, C2, D2, and F2 in the second phase assembly. Each rated phase current of the second phase assembly can be determined as the first rated phase current, i.e., for each of phases A2, B2, C2, D2, and E2, from only two actual phase currents detected in the first phase assembly (e.g., A1, B1 or A1, C1 or A1, D1 or A1, E1 or B1, C1 or B1, D1, etc.).

[0026] It goes without saying that the third phase current of the first phase assembly can also be determined from the measurement of the two phase currents of the first phase assembly. In this case, for the sake of literal interpretation, the phrase "the first phase of the second phase assembly" will be understood as "the third phase of the first phase assembly," or synonymously. Therefore, for example, the rated phase current of the third phase C1 of the first phase assembly can be determined from the measured phase currents of phases A1 and B1. This also applies to systems where each phase assembly has more than three phases, provided that the torsion angle is known.

[0027] It goes without saying that when testing the two actual phase currents in the second phase component, each phase current of the first phase component can also be measured as the rated phase current. In this case, the first phase component can be regarded as the second phase component, and vice versa.

[0028] The first rated phase current can also depend on other parameters. This can be, for example, when the two phase components are to contribute different torque components to the total torque of the motor, or when the phase components are wound differently and thus have different power or torque at the same nominal current flow, such as when the first phase component provides 25 Nm and the second phase component provides 75 Nm, etc. In this case, the rated phase current that should flow in the first phase of the second phase component will also depend, for example, on the desired ratio of the two partial torques and / or the power characteristics of the two phase components in the motor.

[0029] In one improved embodiment, the first actual phase current of the first phase of the first phase assembly is detected by means of a first shunt resistor or a first magnetic sensor. This enables particularly accurate and cost-effective detection of the first actual phase current.

[0030] This method is particularly suitable for using cost-effective shunt resistors as current sensors (shunt sensors). This is because, although these shunt resistors are not necessarily available for measurement at all times depending on the motor's operating conditions, this method can ultimately determine the current in the phase that the shunt resistors cannot precisely measure at any given time (this current is then measured as the rated phase current by the measurable shunt sensor).

[0031] On the other hand, if a sensor that can be measured at any time (such as a Hall sensor) is used, it is possible to eliminate the need for a current sensor for each phase. This is because all other phase currents (as rated phase currents) can be determined by measuring two different phase currents and considering the torsional angle between the connected phases.

[0032] Alternatively or additionally, it can be specified that the second actual phase current of the second phase of the first phase assembly is detected by means of a second shunt resistor or by means of a second magnetic sensor. This achieves particularly accurate and cost-effective detection of the second actual phase current.

[0033] By detecting the actual phase current for each phase of the first phase component, it is advantageous to determine the first rated phase current of the first phase of the second phase component by considering different combinations of each of the two actual phase currents. This allows for a more accurate and redundant determination of the first rated phase current.

[0034] Furthermore, this approach can also be used when sensors that are not available for measurement at all times are not available for measurement. Instead, each additional phase current (from the first phase component and / or from the second phase component) (as a rated value) can be determined by means of two sensors that are precisely available for measurement, using phase current measurements for both phases. Thus, the behavior of the system can be advantageously monitored at any given time.

[0035] Here, for example, a shunt resistor or a magnetic sensor can be used to detect the phase current of the first phase component.

[0036] In one improved embodiment, a rated phase current is measured for each phase of the second-phase assembly. This allows for advantageous, particularly cost-effective, operation of the motor, enabling the rated phase current to be used, for example, as the control current for the second-phase assembly. If a single phase current or all phase currents are measured in the second-phase assembly, it is also advantageous to perform reliability verification of the measured phase currents using the rated phase current. This can be used, for example, to detect fault conditions.

[0037] It goes without saying that in a three-phase motor, for example, the first phase of the second phase component can be any one of the three phases A2, B2, or C2.

[0038] In one improved embodiment, it is specified that another first actual phase current of the first phase of the second phase component is detected, wherein the first rated phase current of the first phase of the second phase component is used as a first value and the other first actual phase current of the first phase of the second phase component is used as a second value, wherein the presence of a motor fault is determined based on the comparison between the first value and the second value (and thus also the fault condition of the current sensor belonging to the motor component).

[0039] In this way, motor monitoring can be advantageously simple and cost-effective. This is because it allows for the reliable verification of the detected first actual phase current of the first phase of the second-phase assembly. Consequently, the highest safety requirements can be met cost-effectively, and, for example, the magnitude and sign of the deviation between the first and second values ​​can identify whether a sensor fault exists, i.e., the detection of the other first actual phase current of the first phase of the second-phase assembly is faulty. However, other fault types, such as winding short circuits, winding open circuits, or short circuits relative to the housing, can also be advantageously identified.

[0040] The other first actual phase current of the first phase of the second phase component can be detected, for example, by means of a shunt resistor or a magnetic sensor.

[0041] One improved embodiment specifies that a fault signal is output when a motor fault is detected. This advantageously triggers the necessity of a fault response or notification response. For example, the fault signal could be a fault setting in the controller. However, the fault signal could also be an acoustic, optical, or tactile signal, accessible, for example, to the motor operator. The operator could then, for example, stop the motor or put it into idle operation in response to the fault signal, etc.

[0042] Here, determining the motor fault includes identifying a current sensor among the motor's current sensors that is displaying an abnormality or has a fault.

[0043] By switching the motor to a safe state when a fault is detected, it is advantageous to prevent external interference from the operator, ensuring the motor is no longer a danger to the operator and / or third parties and / or the motor is not damaged due to the fault. A safe state or operating state could be, for example, shutting off the motor, operating the machine in an emergency operating mode, switching the motor from motor operation to generator operation to generate braking torque, or decoupling the consumer from the motor to achieve no-load operation.

[0044] In one improved embodiment, a first phase of the second phase assembly is energized with a first preset current (as an input current for energizing), which depends on a measured first rated phase current of the first phase of the second phase assembly (which is determined using two measured or detected currents and with knowledge of the torsional angle between the phases).

[0045] In other words, the preset current of the first phase of the second-phase component can be controlled by means of the measured first rated phase current of the first phase of the second-phase component, without having to measure or determine the actual phase current of the first phase of the second-phase component. More precisely, instead of this actual phase current that would otherwise be measured, the first rated phase current is used indirectly or directly as the actual value for controlling the first preset current, and thus the first phase of the second-phase component is energized according to the first rated phase current of the second-phase component.

[0046] This advantageously eliminates the need for a current sensor used to determine or measure the actual phase current of the first phase in a second-phase assembly. This results in savings in cost, materials, signal paths, and space.

[0047] This applies at least to motors that are not critical to safety (e.g., smaller tools such as battery screwdrivers).

[0048] In other words: From the detection of at least two actual phase currents of two different phases of the first phase assembly, a current vector or voltage vector can be determined based on the measured rated phase current of the first phase of the second phase assembly, and this current vector or voltage vector can be used to regulate that phase (or the preset current of that phase). It can be assumed here that the phase position of this current vector or voltage vector (the first phase of the second phase assembly) is offset relative to the detected phase current of the first phase assembly (e.g., by a (fixed) magnitude or by a (fixed) torsional angle). However, the length or amplitude of the current or voltage vector is measured, calculated, or determined based on the measured rated phase current of the first phase of the second phase assembly. This is important, for example, when the two phase assemblies should contribute different torque components to the total torque of the motor. For example, the first phase assembly contributes 30 Nm and the second phase assembly contributes 70 Nm. In this case, the length of the preset current vector (i.e., for the preset phase current), for example, the ratio of the two partial torques and the power characteristics of the two phase assemblies in the motor, are also important. Of course, the amplitudes of the phase assemblies can also be the same.

[0049] In other words, to regulate the preset current in the first and second phase components, it is sufficient to measure or determine exactly two actual phase currents (assuming the torsional angle between the phases is known). The actual value required for regulation can then be obtained either from the measured or determined actual phase currents or from the rated phase currents determined from these actual phase currents.

[0050] In one improved embodiment, each phase of the second-phase assembly is energized using a preset current, where each preset current depends on the rated phase current of the second-phase assembly measured for the corresponding phase. In other words, the preset currents (as rated values ​​for regulation) of all phases of the second-phase assembly are regulated by the measured rated phase currents (as actual values), wherein the rated phase currents are corrected if necessary (e.g., due to aging effects, different torque components of the two phase assemblies, temperature, etc.) before being supplied to the regulator as actual values. Therefore, the phases are regulated or energized with preset currents based on the separately measured rated phase currents of the second-phase assembly.

[0051] This advantageously enables the second-phase assembly to function entirely without its own current-measuring sensor, and thus allows for very cost-effective, space-saving, and simple manufacturing.

[0052] According to a second aspect of the invention, a controller for an electric motor is provided.

[0053] The motor has a rotor and a stator, wherein the rotor is arranged anti-torsional on a shaft rotatably supported in a housing, and the stator is fixedly arranged to the housing and has a stator winding having a first phase assembly and a second phase assembly electrically separated from the first phase assembly, wherein each phase assembly has the same number of phases, and wherein identical phases of the first phase assembly are arranged to be torsional relative to identical phases of the second phase assembly by a torsion angle. Here, the controller is configured to execute the above method.

[0054] According to a third aspect of the present invention, an electric motor is provided.

[0055] The motor has a rotor and a stator, wherein the rotor is arranged anti-torsional on a shaft rotatably supported in a housing, and the stator is fixedly arranged to the housing and has a stator winding having a first phase assembly and a second phase assembly electrically separated from the first phase assembly, wherein each phase assembly has the same number of phases, and wherein identical phases of the first phase assembly are arranged to be torsional relative to identical phases of the second phase assembly by a torsion angle. The motor also has a controller as described above.

[0056] This motor can be advantageously manufactured very simply, in a space-saving and cost-effective manner. It can, for example, meet safety-critical requirements such as ISO 26262, without requiring redundantly constructed current sensor devices in each phase.

[0057] In one improved embodiment, the first actual phase current of the first phase of the first phase assembly is detected by means of a first shunt resistor or by means of a first magnetic sensor.

[0058] This allows for particularly accurate and cost-effective detection of the first actual phase current.

[0059] Alternatively or additionally, it can be specified that the second actual phase current of the second phase of the first phase assembly is detected by means of a second shunt resistor or by means of a second magnetic sensor.

[0060] This allows for the particularly accurate and cost-effective detection of the second actual phase current. Attached Figure Description

[0061] Other features and advantages of the present invention will become apparent to those skilled in the art from the following description of exemplary embodiments with reference to the accompanying drawings; however, these embodiments should not be construed as limiting the invention. Wherein shown:

[0062] Figure 1 A schematic sketch of the motor and inverter is shown;

[0063] Figure 2 A detailed section of the motor in 1 is shown;

[0064] Figure 3 A flowchart is shown illustrating the process for running... Figure 1 and Figure 2 An embodiment of the method for using a motor;

[0065] Figure 4 A flowchart is shown illustrating the process for running... Figure 1 and Figure 2 Another embodiment of the method for using a motor. Detailed Implementation

[0066] Figure 1 A schematic sketch of a motor system 100 is shown, which includes a motor 1 and an inverter 10. The motor has a rotor 2 and a stator 3, wherein the rotor 2 is arranged anti-torsionally on a shaft 5 rotatably supported in a housing 4, wherein the stator 3 is fixedly arranged to the housing and has stator windings with a first phase assembly P1 and a second phase assembly P2 electrically separated from the first phase assembly P1, wherein the phase assemblies P1 and P2 each have the same number of three phases A1, B1, and C1 for the first phase assembly, and similarly have three phases A2, B2, and C2 for the second phase assembly P2. The same phases A1, B1, and C1 of the first phase assembly P1 are tortuous relative to the same phases A2, B2, and C2 of the second phase assembly P2 by a torsion angle Δφ of 30° (i.e., A1 relative to A2: 30°, B1 relative to B2: 30°, and C1 relative to C2: 30°). Phases A1, B1, and C1 of the first phase component P1 are controlled according to the rotation angle of the rotor 2.

[0067] Furthermore, the inverter 10 includes a circuit carrier 11 having electronic circuitry 13, or control logic device 13. The circuit carrier 11 may, for example, be part of a controller. The electronic circuitry 13 is connected to a DC link 12 and can regulate or control the DC link 12 or receive signals from the DC link 12, which may, for example, have an intermediate loop capacitor. Two lines are run in the DC link 12, both having a ground potential (“GND”) and, exemplary only, a voltage of 48V.

[0068] Furthermore, the electronic circuit 13 is configured to control or regulate the first power electronic device 14, the second power electronic device 15, and the third power electronic device 16. The three power electronic devices—modules 13, 14, and 15—are supplied with current and voltage by the DC link 12.

[0069] The first power electronic device 14 controls three phases A1, B1, and C1 of the first phase assembly P1 of the stator 3 of the motor 1 via three phase lines (first phase line 20, second phase line 21, and third phase line 22). The second power electronic device 15 controls three phases A2, B2, and C2 of the second phase assembly P2 of the stator 3 of the motor 1 via three phase lines (fourth phase line 30, fifth phase line 31, and sixth phase line 32). The third power electronic device 16 controls the energization of the rotor 2 via the first rotor line 40 and the second rotor line 41.

[0070] In order to effectively control phases A1, B1, and C1 of the first phase assembly P1, a rotor position sensor 18 connected to the electronic circuit 13 is provided. The electronic circuit 13 controls at least the first phase assembly P1 based on the position of the rotor 2 relative to the stator 3, or simply based on the rotation angle of the rotor 2.

[0071] The control of phases A2, B2, and C2 of the second phase assembly can be performed in a phase-shift manner relative to the control of phases A1, B1, and C1 of the first phase assembly P1, wherein the movement can be based on a torsion angle Δφ. For example, this movement can correspond to a torsion angle Δφ.

[0072] Furthermore, in motor 1, at least two actual phase currents of two different phases of the first phase assembly P1, namely the first actual phase current I1, are detected by a current sensor (not shown here). Ist，P1 Second actual phase current I2 Ist，P1 The current sensor can be designed as a Hall sensor or a shunt resistor, for example. In this embodiment, the third actual phase current I3 can also be detected, by way of example. Ist，P1 .

[0073] Given two actual phase currents, for example, two actual phase currents I1 Ist，P1 and I2 Ist，P1 Based on the following parameters:

[0074] -- The first actual phase current I1 of the first phase of the first phase component P1 Ist，P1 ,

[0075] -- The second actual phase current I2 of the second phase of the first phase component P1 Ist，P1 ,

[0076] -- In its first phase current I1 Ist，P1 The first phase of the first phase component P1 and its rated phase current I1 have been measured. Soll，P2 The first angle difference α between the first phases of the second phase component P2 to be measured

[0077] -- In its second actual phase current I2 Ist，P1The second phase of the first phase component P1 and its rated phase current I1 have been tested. Soll，P2 The second angle difference β between the first phases of the second-phase component P2 to be measured,

[0078] The first rated phase current I1 of the first phase of the second phase component P2 can be measured. Soll，P2 .

[0079] Figure 2 Show Figure 1 A magnified partial view of motor 1 is shown. The surrounding angle φ is shown here, which surrounds motor 1 in a clockwise direction. The three phases A1, B1, and C1 of the first phase assembly P1 are arranged at positions 0°, 120°, and 240°. The three phases A2, B2, and C2 of the second phase assembly P2 are arranged with a torsion angle Δφ = 30° relative to the corresponding phases A1, B1, and C1 of the first phase assembly P1, i.e., at positions 30°, 150°, and 270°.

[0080] It goes without saying that more than three phases can be set, such as four, five, or six, or only two phases can be set. In a five-phase system, the five phases A1, B1, C1, D1, and E1 can be arranged, for example, staggered from each other by 72°, starting with A1 = 0°. The five phases of the second phase component P2 can be arranged with a torsional angle relative to the five phases of the first phase component P1, for example, by a torsional angle of Δφ = 20°, i.e., at A2 = 20°, B2 = 92°, C2 = 164°, D2 = 236°, and E2 = 308° in this example.

[0081] exist Figure 2 In the example, the first actual phase current I1 is the first phase current of the first phase component P1. Ist，P1 The measured current of the first phase A1 (in principle, "first phase" can also be B1 or C1) is detected and used as the second actual phase current I2 of the first phase component P1. Ist，P1 The measured current of the second phase C1 is detected (in principle, this second phase can be any phase different from the first phase). The first rated phase current I1 of the first phase, which is the component P2 of the second phase, is also measured. Soll，P2 Consider phase B2 here (in principle, but this could also be one of two other phases, A2 or C2).

[0082] In the motor 1 shown, it is now assumed that the two phase components are identical in terms of their power characteristics and that the two phase components should provide the same torque component.

[0083] In this case, the first rated phase voltage I1 of the first phase of the second phase component P2 Soll，P2 For example, it can be determined using the following equation:

[0084] (Equation 1)

[0085] in:

[0086] α = φ (first phase of second phase component P2) - φ (first phase of first phase component P1);

[0087] β = φ (first phase of second phase component P2) - φ (second phase of first phase component P1).

[0088] In other words:

[0089] α, as the first angle difference, corresponds to its first rated phase current I1 Soll，P2 The first phase of the second phase component P2 to be measured relative to its first actual phase current I1 Ist，P1 The torsional angle between the first phases of the first phase component P1 being tested;

[0090] β, as the second angle difference, corresponds to its first rated phase current I1. Soll，P2 The first phase of the second phase component P2 to be measured relative to its second actual phase current I2 Ist，P1 The torsion angle between the second phase and the first phase component P1 being tested.

[0091] exist Figure 2 The example corresponding to

[0092] α = φ(B2) - φ(A1) = +150° - 0° = +150°, and

[0093] β=φ(B2)-φ(C1)=(150°+360°)-240°=+270°.

[0094] It should be considered that the phase angle of B2 with 150° corresponds to a phase angle of 360° + 150°.

[0095] It goes without saying that the third phase current of the first phase assembly can also be determined from the measurement of the two phase currents of the first phase assembly. In this case, the statement "the first phase of the second phase assembly" is understood as "the third phase of the first phase assembly" or synonymous with it. Therefore, for example, the rated phase current of the third phase C1 of the first phase assembly can be determined from the measured phase currents of phases A1 and B1. This also applies to systems where each phase assembly has more than three phases, provided that the torsion angle is known.

[0096] Figure 3 The following flowchart illustrates the process for running... Figure 1 and 2An embodiment of the method for monitoring motor 1 is provided. Here, the method can also refer to a method for monitoring motor 1, wherein monitoring motor 1 may also include outputting a fault signal and / or switching motor 1 to a safe operating state. Here, the steps taken in or for the first phase assembly P1 are shown on the left, and the steps taken in or for the second phase assembly P2 are shown on the right.

[0097] First, in step 200, a preset phase current I is used. Vorgabe，A1，B1，C1 The three phases A1, B1, and C1 of the first phase component P1 are energized (these are preset phase currents I). Vorgabe，A1，B1，C1 This can be understood as the regulated rated value. These are provided, for example, by the first power electronic device 14. In step 210, the first and second actual phase currents I1 of the first phase assembly P1 are detected on at least two phases (the first and second phases of the first phase assembly P1). Ist，P1 I2 Ist，P1 This can be achieved, for example, by using a shunt resistor or a Hall sensor. In this embodiment, the third actual phase current I3 can be detected, by way of example. Ist，P1 .

[0098] Three actual phase currents I1 Ist，P1 I2 Ist，P1 I3 Ist，P1 This can then be fed back to step 200 as a preset phase current I for regulating the first phase component. Vorgabe，A1，B1，C1 The actual value (which is the rated value used for regulation here). In other words: the regulation is matched to the current load on a single phase so that the actual phase current I1 Ist，P1 I2 Ist，P1 I3 Ist，P1 (As quickly as possible) corresponds to the preset phase current I Vorgabe，A1，B1，C1 Or as close as possible to the preset phase current.

[0099] In step 220, based on the first and second actual phase currents I1 of the first phase component P1 Ist，P1 I2 Ist，P1 The first rated phase current I1 of the first phase of the second phase component P2 is determined by the first and second angle differences α and β. Soll，P2 (In principle, the rated phase current of the third phase of the first phase component can also be measured here). This can be achieved, for example, according to the relationship in Equation 1. However, in motor 1 where the power characteristics or the torque to be output of the first and second phase components P1 and P2 are different, it may be necessary to modify the relationship in Equation 1. Similarly, factors such as temperature effects and aging effects may require modifications to the relationship in Equation 1.

[0100] If, for example, the current sensor is removed for the third phase of the first phase assembly, then the rated phase current of the third phase of the first phase assembly, as determined here, can then be used after step 220 as the actual value for regulation (or a correction value determined therefrom, for example, for temperature effects, aging, etc.).

[0101] In the second phase assembly P2, the three phases A2, B2, and C2 are subjected to a preset phase current I, for example, provided by the second power electronics 15, in step 300. Vorgabe，A2，B2，C2 They can be energized, for example, with the preset phase current I of the first phase component P1. Vorgabe，A1，B1，C1 It is calculated or determined irrelevantly. In step 310, another first actual phase current I1* of the second phase component P2 is detected on at least two phases (the first and second phases of the second phase component P2). Ist，P2 And another second actual phase current I2* Ist，P2 In this embodiment, another third actual phase current I3* can also be detected, by way of example. Ist，P2 .

[0102] Three additional actual phase currents I1* Ist，P2 I2* Ist，P2 I3* Ist，P2 This can then be fed back to step 300 as a preset phase current I for regulating the second phase component. Vorgabe，A2，B2，C2 The actual value (which is the rated value used for regulation here). In other words: the regulation is matched to the current load on a single phase so that the actual phase current I1* Ist，P2 I2* Ist，P2 I3* Ist，P2 As close as possible to the preset phase current I Vorgabe，A2，B2，C2 .

[0103] In step 320, based on two of the other actual phase currents, here: based on another first and another second actual phase current I1* of the second phase component P2. Ist，P2 I2* Ist，P2 And for the selected phase, the effective first and second angle differences α, β determine another first rated phase current I1* of the first phase of the first phase assembly P1. Soll，P1 This can be achieved, for example, by using the matched actual and rated phase currents according to the relationship in Equation 1. However, in motor 1 where the power characteristics of the first and second phase components P1 and P2 are different, or where the output torque is different, it may be necessary to modify the relationship in Equation 1. This also applies to considerations of temperature effects, aging phenomena, etc.

[0104] In step 330, a comparison can now be made, for example, to perform a confidence check. For this purpose, the first rated phase current I1 of the first phase of the second phase component P2 is now...Soll，P2 The measured value is used as the first value W1 and the other first actual phase current I1 of the first phase of the second phase component P2. Ist，P2 The detected or measured value is compared with the second value W2.

[0105] It goes without saying that in step 330, the measured rated phase current I2 of the second or third phase of the second phase component P2 can also be used. Soll，P2 I3 Soll，P2 The measured second or third actual phase current I2* of the second or third phase of the first phase component P1, which is the first value W1. Ist，P2 I3* Ist，P2 It is compared as the second value W2.

[0106] The comparison determines whether a fault signal should be output. In other words, the first value W1 can be verified for reliability using the second value W2. If the two values ​​W1 and W2 deviate significantly from each other beyond a predefined tolerance range, a fault is identified. This can be triggered, for example, by a faulty current sensor or by a short circuit or open circuit in the winding of one of the phases. If a fault is identified, a fault signal is output and / or the machine is switched to a safe operating state.

[0107] If these values ​​are within a preset tolerance range relative to each other, it is assumed that the motor is in a safe operating state and the current sensing sensor is functioning properly.

[0108] In the same way, the reliability of current measurements on the phases of the first phase component can be verified or monitored.

[0109] Therefore, a comparison can be made in step 230, for example, to perform a confidence check. For this purpose, the other first rated phase current I1* of the first phase of the first phase component P1 is now compared. Soll，P1 The measured value is taken as the first value W1* and the first actual phase current I1 of the first phase of the first phase component P1. Ist，P1 The detected or measured value is compared as another second value W2*.

[0110] It goes without saying that in step 230, the additional measured rated phase current I2* of the second or third phase of the first phase component P1 can also be used. Soll，P1 I3* Soll，P1 As another first value W1*, the measured second or third actual phase current I2 of the second or third phase of the first phase component P1. Ist，P1 I3 Ist，P1 It is compared as another second value, W2*.

[0111] In principle, the measured rated phase current I3* of the third phase of the second phase component P1 can also be used here. Soll，P2 The measured third actual phase current I3* is the third phase of the third phase, which is the first value W1 and the second phase component P2. Ist，P2 Compare it as another second value, W2*. Figure 3 The flowchart shown does not illustrate this comparison.

[0112] Here, a fault signal can also be output based on the comparison and / or the motor 1 can be switched to a safe operating state.

[0113] In principle, in step 230, the measured rated phase current I3 of the third phase of the first phase component P1 can also be used. Soll，P1 As another first value W1*, the measured third actual phase current I3 of the third phase of the first phase component P1. Ist，P1 It is compared as another second value, W2*. However, in Figure 3 The flowchart shown does not illustrate this comparison, therefore it is necessary to start from step 220 and compare the measured rated phase current I3 of the third phase of the first phase component P1. Soll，P1 As another first value W1*, it is fed in (from the right) in step 230.

[0114] In principle, in step 330, the measured third rated phase current I3* of the third phase of the second phase component P2 can also be used. Soll，P2 The measured third actual phase current I3* is the third phase of the third phase, which is the first value W1 and the second phase component P2. Ist，P1 It is compared as the second value, W2. Figure 3 The flowchart shown does not illustrate this comparison, therefore it is necessary to start from step 320 and compare the measured third-phase current I3* of the third phase of the second-phase component P2. Soll，P1 The first value W1 is fed in during step 330 (from the left).

[0115] The advantage of this method is that it allows for reliable verification of whether the motor is operating correctly using only a single, unique current sensor or current measurement sensor for each phase. It can also determine whether the current sensor is functioning correctly or is defective.

[0116] Figure 4 The following flowchart illustrates the process for running... Figure 1 and 2Another embodiment of the method for motor 1. This method can also be used, for example, for motors in which current sensor data or torque reliability verification is not required, such as for consumer appliances, like battery screwdrivers or household appliances. Here, the regulation of the second phase component P2 can be performed particularly cost-effectively because no current sensor is required on the phase of the second phase component P2 to provide the actual value for regulation. The otherwise necessary reverse coupling is achieved through... Figure 4 The dashed lines in the diagram illustrate the components (especially step 310 and the dashed lines), and it is advantageous to omit these dashed elements (especially current measurements) in the described method.

[0117] Instead, the actual value for regulating the second-phase component P2 is calculated or determined based on the rated phase current of the second-phase component P2 measured in step 220. Therefore, the phase current I1 of the measured second-phase component P2 is used to... Soll，P2 I2 Soll，P2 I3 Soll，P2 With preset current I Vorgabe，A2，B2，C2 To power the second phase assembly P2 (A2, B2, C2), two current sensors are sufficient: one current sensor is installed on each of the two phases of the first phase assembly P1.

[0118] and Figure 3 The same method steps are used here as the method steps. Figure 3 The same reference numerals are used in the accompanying drawings.

[0119] First, in step 200, according to the preset phase current I Vorgabe，A1，B1，C1 To energize the three phases A1, B1, and C1 of the first phase component P1.

[0120] Similarly, in step 300, by means of a preset current I Vorgabe，A2，B2，C2 Power on the three phases A2, B2, and C2 of the second phase component P2.

[0121] In step 210, the first and second actual phase currents I1 of the first phase component P1 are detected or measured on at least two phases of the phase (the first and second phases of the first phase component P1). Ist，P1 I2 Ist，P1 This can be achieved, for example, through a shunt resistor or a Hall sensor.

[0122] In step 220, based on the first and second actual phase currents I1 of the first phase component P1 Ist，P1 I2 Ist，P1 And the first rated phase current I1 of the first phase of the second phase component P2 is determined by the first and second angle differences α and β. Soll，P2This can be done, for example, using the relationship in Equation 1. However, in motor 1 where the power characteristics of the first and second phase components P1 and P2 are different, or where the torque to be output is different, it may be necessary to modify the relationship in Equation 1. But this can also be done in the next step (step 240).

[0123] It is also possible to measure the second rated phase current I2 of the second phase component P2. Soll，P2 and the third rated phase current I3 Soll，P2 Similarly, the third rated phase current I3 of the first phase component P1 can also be measured. Soll，P1 .

[0124] In step 240, the first rated phase current I1 of the first phase of the second phase component P2 is now... Soll，P2 To determine the first virtual actual value I1 of the first phase used to regulate the second phase component P2 virtuell，P2 Here, for example, the torque shares to be output of the two phase components P1 and P2 can be considered, provided that this has not yet been considered in step 220. Furthermore, aspects such as temperature effects, the power characteristics of the second phase component P2, aging effects, etc., can be considered.

[0125] However, the following situation also exists, where the first virtual actual value I1 of the first phase of the second phase component P2 is also possible. virtuell，P2 The first rated phase current I1 of the first phase of the second phase component P2 remains unchanged. Soll，P2 If no modifications are needed, step 240 can be cancelled.

[0126] The first virtual real value I1 of the first phase of the second phase component P2 virtuell，P2 The process now proceeds to step 300, which involves energizing the second-phase component P2, thereby enabling the second-phase component P2 to be energized in a controlled manner. For this purpose, the preset current of the first phase for the second-phase component P2 is readjusted for such a long period until the first virtual actual value I1 is reached. virtuell，P2 It is consistent with the corresponding preset current used for the first phase (approximately).

[0127] Similarly, in step 240, the second rated phase current I2 of the second phase component P2 can also be used. Soll，P2 Determine the second virtual actual value I2 virtuell，P2 And by the third rated phase current I3 of the second phase component P2 Soll，P2 Determine the third virtual actual value I3 virtuell，P2 Then, similarly, in order to regulate the second phase component, it can be compared with the preset current I of the second phase component P2, which is the rated value. Vorgabe，A2，B2，C2 Compare them.

[0128] In this way, in principle, only two detected actual phase currents from two different phases of the first phase component P1 can be effectively used to energize all phases of the second phase component P2, or to energize it in the control loop. Similarly, the third phase of the first phase component can also be energized in a controlled manner (without measurement). In this way, the motor 1 can, for example, operate at its optimal point of use. Here, separate torque identification is not required, and only two current sensors are needed in the motor 1, wherein, of course, for example, one current measuring sensor can also be provided on each phase of the first phase component P1.

[0129] It should be noted that, for clarity, the control loop for the first phase component P1 with feedback is not shown. This means that it is not shown how the actual phase current of the first phase component measured in step 210 or the rated phase current measured in step 220 is fed back as an actual value to the control in step 200. This control feedback can be obtained from... Figure 3 I learned this from the middle.

Claims

1. Method for operating an electric machine, the electric machine having a rotor (2) and a stator (3), wherein the rotor (2) being arranged torsionally fixed on a shaft (5) rotatably supported in a housing (4), wherein the stator (3) is arranged fixed with the housing and has a stator winding, the stator winding having a first phase assembly (PI) and a second phase assembly (P2) electrically separated from the first phase assembly (PI), and wherein the phase assemblies (PI, P2) each have the same number of phases, wherein the same phases (Al, Bl, Cl) of the first phase assembly (PI) are arranged with a torsion angle (Δφ) relative to the same phases (A2, B2, C2) of the second phase assembly (P2), wherein the phases (Al, Bl, Cl) of the first phase assembly (PI) are controlled in dependence on a rotation angle of the rotor (2), wherein the phases (A2, B2, C2) of the second phase assembly (P2) are controlled in phase displacement relative to the phases (Al, Bl, Cl) of the first phase assembly (PI) in dependence on the torsion angle (Δφ), wherein at least one first actual phase current (I1 Ist，P1 ) of a first phase of the first phase assembly (P1) is detected, And wherein a second actual phase current (I2 Ist，P1 ) of a second phase of the first phase assembly (P1) is detected, characterized in that in dependence on the following parameters: -- a first actual phase current (I1 Ist，P1 ) of a first phase of the first phase assembly (P1 Ist，P1 ) -- a second actual phase current (I2 Ist，P1 ) of a second phase of the first phase assembly (P1) - a first angle difference (a) between a first phase of the first phase assembly (PI) and a first phase of the second phase assembly (P2) or a third phase of the first phase assembly (PI), - a second angle difference (β) between a second phase of the first phase assembly (PI) and a first phase of the second phase assembly (P2) or a third phase of the first phase assembly (PI), to determine a first rated phase current (I1 Soll，P2 ) of a first phase of the second phase assembly (P2) or a rated phase current of a third phase of the first phase assembly (P1), wherein a further first actual phase current (I1 Ist，P2 ) of a first phase of the second phase assembly (P2) is detected, wherein a first rated phase current (I1 Soll，P2 ) of a first phase of the second phase assembly (P2) is compared as a first value (W1) with another first actual phase current (I1 Ist，P2 ) of the first phase of the second phase assembly (P2) as a second value (W2), wherein it is determined in dependence on a comparison between the first value (Wl) and the second value (W2) whether a fault of the electric machine (1) exists.

2. Method according to claim 1, wherein The first actual phase current (I1) is detected by means of the first shunt resistor or by means of the first magnetic sensor Ist，P1 ) and / or wherein the second actual phase current (I2) is detected by means of the second shunt resistor or by means of the second magnetic sensor Ist，P1}.

3. Method according to claim 1 or 2, wherein actual phase currents (I1 Ist，P1 , I2 Ist，P1 , I3 Ist，P1 ) are detected for each phase (A1, B1, C1) of the first phase assembly (P1).

4. Method according to claim 1 or 2, characterized in that A rated phase current (I1 Soll，P2 , I2 Soll，P2 , I3 Soll，P2 ) is determined for each phase (A2, B2, C2) of the second phase assembly (P2) separately.

5. Method according to claim 1 or 2, wherein - detecting another first actual phase current (I1 Ist，P2 ) of a first phase of the second phase assembly (P2) by means of a shunt resistor or a magnetic sensor.

6. Method according to claim 1 or 2, wherein a fault signal is outputted when the electric machine (1) is determined to be faulty.

7. Method according to claim 1 or 2, wherein the electric machine (1) is transferred into a safe state when the electric machine (1) is determined to be faulty.

8. Method according to claim 1 or 2, wherein a first phase of the second phase assembly (P2) is energized with a first preset current (I1 Vorgabe，P2 ) depending on a determined first nominal phase current (I1 Soll，P2 ) of the first phase of the second phase assembly (P2).

9. Method according to claim 4, wherein, each phase (A2, B2, C2) of said second phase assembly (P2) is energized with a preset current (I1 Vorgabe，P2 , I2 Vorgabe，P2 , I3 Vorgabe，P2 ), wherein each of said preset currents (I1 Vorgabe，P2 , I2 Vorgabe，P2 , I3 Vorgabe，P2 ) depends on a rated phase current (I1 Soll，P2 , I2 Soll，P2 , I3 Soll，P2 ) determined for the respective phase (A2, B2, C2) of said second phase assembly (P2).

10. Method according to claim 1, wherein the electric machine is an electric machine of a motor vehicle.

11. Method according to claim 3, wherein, The actual phase currents (I1 Ist，P1 , I2 Ist，P1 , I3 Ist，P1 ) are detected for each phase (A1, B1, C1) of the first phase assembly (P1) by means of a shunt resistor or a magnetic sensor, respectively.

12. Controller for an electric machine, the electric machine having a rotor (2) and a stator (3), wherein the rotor (2) being arranged torsionally fixed on a shaft (5) rotatably supported in a housing (4), wherein the stator (3) is arranged fixed with the housing and has a stator winding, the stator winding having a first phase assembly (PI) and a second phase assembly (P2) electrically separated from the first phase assembly (PI), wherein the phase assemblies (PI, P2) each have the same number of phases, wherein the same phases (Al, Bl, Cl) of the first phase assembly (PI) are arranged with a torsion angle (Δφ) relative to the same phases (A2, B2, C2) of the second phase assembly (P2), wherein the phases (Al, Bl, Cl) of the first phase assembly (PI) are controlled in dependence on a rotation angle of the rotor (2), wherein the phases (A2, B2, C2) of the second phase assembly (P2) are controlled in phase displacement relative to the phases (Al, Bl, Cl) of the first phase assembly (PI) in dependence on the torsion angle (Δφ), characterized in that in dependence on the following parameters: - a first angle difference (a) between a first phase of the first phase assembly (PI) and a first phase of the second phase assembly (P2) or a third phase of the first phase assembly (PI), - a second angle difference (β) between a second phase of the first phase assembly (PI) and a first phase of the second phase assembly (P2) or a third phase of the first phase assembly (PI), wherein it is determined in dependence on a comparison between the first value (Wl) and the second value (W2) whether a fault of the electric machine (1) exists. wherein the same phases (A1, B1, C1) of the first phase package (P1) are arranged with a twist angle (Δφ) relative to the same phases (A2, B2, C2) of the second phase package (P2), wherein the controller is configured to perform the method according to any one of claims 1 to 11.

13. An electric machine having a rotor (2) and a stator (3), wherein the rotor (2) being arranged torsionally fixed on a shaft (5) rotatably supported in a housing (4), wherein the stator (3) is arranged fixed with the housing and has a stator winding having a first phase package (P1) and a second phase package (P2) electrically separated from the first phase package (P1), wherein the phase packages (P1, P2) each have the same number of phases, wherein the same phases (A1, B1, C1) of the first phase package (P1) are arranged with a twist angle (Δφ) relative to the same phases (A2, B2, C2) of the second phase package (P2), characterized in that the controller is according to claim 12.

14. The electric machine according to claim 13, wherein, The first actual phase current (I1) of the first phase (P1) of the first phase assembly (P1) is detected by means of the first shunt resistor or by means of the first magnetic sensor Ist，P1 ), wherein the second actual phase current (I2) of the second phase of the first phase assembly (P1 ) is detected by means of the second shunt resistor or by means of the second magnetic sensor Ist，P1 .

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