阅读说明：本技术 用于运行针对机动车中的电蓄能器的充电控制器的方法 (Method for operating a charge controller for an electrical energy accumulator in a motor vehicle ) 是由 B.雷内克 J.穆勒 W.费舍尔 S.葛罗德 于 2018-11-29 设计创作，主要内容包括：本发明涉及一种用于运行针对电蓄能器(S)、尤其是车载电网(100)的电池组(B)的充电控制器(LR)的方法,所述充电控制器能利用电机(30)来加载电能,所述电机直接或经传动地耦合或能耦合到内燃机(112)上,所述电机包括转子(32)、定子(33),所述定子具有至少一个生成相信号(U<Sub>U</Sub>、U<Sub>V</Sub>、U<Sub>W</Sub>、I<Sub>U</Sub>、I<Sub>V</Sub>、I<Sub>W</Sub>)的相绕组(U、V、W),其中在达到或超过所述电蓄能器(S)的第一额定值(U<Sub>soll1</Sub>)之后,所述电机(30)通过所述充电控制器(LR)被操控为使得所述电机(30)以电动机方式来运行。本发明还涉及：一种相对应的计算单元,所述计算机单元被设立用于执行所述方法；以及一种用于执行所述方法的计算机程序。(The invention relates to a method for operating a charging controller (L R) for an electrical energy store (S), in particular a battery pack (B) of a vehicle electrical system (100), which can be supplied with electrical energy by means of an electric machine (30) that is directly or drivingly coupled or can be coupled to an internal combustion engine (112), comprising a rotor (32), a stator (33) having at least one phase signal (U) that is generated U 、U V 、U W 、I U 、I V 、I W ) Phase winding (U, B, C),V, W), wherein the first setpoint value (U) of the electrical energy store (S) is reached or exceeded soll1 ) The electric machine (30) is then operated by the charging controller (L R) in such a way that the electric machine (30) operates as a motor, and a corresponding computer unit, which is set up to carry out the method, and a computer program for carrying out the method.)

1. Method for operating a charging controller (L R) for an electrical energy store (S), in particular a battery pack (B) of a vehicle electrical system (100), which can be charged with electrical energy by means of an electric machine (30) which is coupled directly or in a driven manner to an internal combustion engine (112) and comprises a rotor (32), a stator (R33) The stator having at least one generating phase signal (U)_U、U_V、U_W、I_U、I_V、I_W) In the phase winding (U, V, W), wherein the first rated value (U) of the electrical energy accumulator (S) is reached or exceeded_soll1) Thereafter, the electric machine (30) is controlled by the charging controller (L R) such that the electric machine (30) operates as a motor.

2. Method according to claim 1, wherein the further nominal value (U) is reached or fallen below_soll2) The electric machine (30) is then controlled by the charging controller (L R) in such a way that the electric machine (30) operates as a generator, the further setpoint value being less than the first setpoint value (U)_soll1）。

3. Method according to claim 1 or 2, wherein the first setpoint value (U) of the electrical energy accumulator (S)_soll1) And/or another nominal value (U)_soll2) Is predefined as a function of the rotational speed (n) of the electric motor (30).

4. Method according to at least one of the preceding claims, wherein a first nominal value (U) of the electrical energy accumulator (S)_soll1) And/or another nominal value (U)_soll2) Is predefined as a function of at least one operating point and/or operating state of the internal combustion engine (112).

5. Method according to at least any one of the preceding claims, wherein at least one value (W) is detected_Uu、W_Ud、W_Vu、W_Vd、W_Wu、W_Wd、W_U0、W_V0、W_W0) Said at least one value occurring at least once per revolution of the rotor (32) and at least corresponding to the phase signal (U)_U、U_V、U_W、I_U、I_V、I_W) Rising edge (Fl)_Uu、Fl_Vu、Fl_Wu) The phase signal (U)_U、U_V、U_W、I_U、I_V、I_W) Falling edge (Fl)_Ud、Fl_Vd、Fl_Wd) Or the phase signal (U)_U、U_V、U_W、I_U、I_V、I_W) Is associated with the zero crossing, wherein the at least one value (W) occurs_Uu、W_Ud、W_Vu、W_Vd、W_Wu、W_Wd、W_U0、W_V0、W_W0) The electric machine (30) is then operated by the charging controller (L R) in the form of a motor or in the form of a generator.

6. Method according to any one of the preceding claims, wherein the operation of the electrical machine (30) in motor mode or in generator mode is dependent on at least one rotational angle position (α) of the rotor (32)_Phase) To be executed.

7. The method according to any of the preceding claims, wherein said at least one value (W) occurs_Uu、W_Ud、W_Vu、W_Vd、W_Wu、W_Wd、W_U0、W_V0、W_W0) Thereafter, the motor-or generator-mode operation of the electric machine (30) is maintained until at least one further value (W) is detected_Uu、W_Ud、W_Vu、W_Vd、W_Wu、W_Wd、W_U0、W_V0、W_W0) Said at least one other value being associated with said phase signal (U)_U、U_V、U_W、I_U、I_V、I_W) Subsequent rising edge (Fl)_Uu、Fl_Vu、Fl_Wu) The phase signal (U)_U、U_V、U_W、I_U、I_V、I_W) Falling edge (Fl)_Ud、Fl_Vd、Fl_Wd) Or the phase signal (U)_U、U_V、U_W、I_U、I_V、I_W) Is associated with the zero crossing.

8. The method according to any of the preceding claims, wherein the phase signal (U) if distance from it_U、U_V、U_W、I_U、I_V、I_W) Rising edge (Fl)_Uu、Fl_Vu、Fl_Wu) The phase signal (U)_U、U_V、U_W、I_U、I_V、I_W) Falling edge (Fl)_Ud、Fl_Vd、Fl_Wd) Or the phase signal (U)_U、U_V、U_W、I_U、I_V、I_W) At least one value (W) associated with the zero crossing of_Uu、W_Ud、W_Vu、W_Vd、W_Wu、W_Wd、W_U0、W_V0、W_W0) There is at least one minimum time interval (T)_min) A switching process of the charging controller (L R) is initiated for the operation of the electric machine (30) in the form of a motor or in the form of a generator.

9. Method according to any one of the preceding claims, wherein upon identification of the value (W)_Uu、W_Ud、W_Vu、W_Vd、W_Wu、W_Wd、W_U0、W_V0、W_W0) A switching process of the charging controller (L R) is then initiated with a time delay for the operation of the electric machine (30) in the motor mode or in the generator mode.

10. Method according to any one of the preceding claims, wherein the first value (W) is identified in the first mode_Uu、W_Ud、W_Vu、W_Vd、W_Wu、W_Wd、W_U0、W_V0、W_W0) Wherein the value (W) is identified_Uu、W_Ud、W_Vu、W_Vd、W_Wu、W_Wd、W_U0、W_V0、W_W0) Thereafter, a change is made from the first mode to a further mode, in which a motor-or generator-mode operation of the electric machine (30) is initiated.

11. Method according to any one of the preceding claims, wherein the electric machine (30) is operated by the charging controller (L R) in a timed manner for motor-or generator-mode operation of the electric machine (30), in particular upon occurrence of the at least one value (W ™)_Uu、W_Ud、W_Vu、W_Vd、W_Wu、W_Wd、W_U0、W_V0、W_W0) Thereafter, the operation is clocked, preferably by means of Pulse Width Modulation (PWM).

12. Method according to claim 9, wherein the time control (PWM) is selected such that the operating voltage (U) of the electrical accumulator (S) is at the first nominal value (U)_soll1) And the other rated value (U)_soll2) Preferably by a constant value (U)_const）。

13. The method of any of the above claims, wherein one or more phase signals (U) of the electric machine (30)_U、U_V、U_W、I_U、I_V、I_W) Is processed by means of an electronic circuit, in particular an engine control device (122).

14. A computing unit, preferably an engine control device (122) for an internal combustion engine (12), which is set up by a corresponding integrated circuit and/or by a computer program stored on a memory as: performing the method according to any of the preceding claims.

15. A computer program which, when executed on a computing unit, causes the computing unit to perform a method according to any one of claims 1 to 13.

16. A machine readable storage medium having stored thereon a computer program according to claim 15.

Technical Field

The invention relates to a method for operating a charge controller for an electrical energy store, in particular a battery pack of a vehicle electrical system, which charge controller can be charged with electrical energy by means of an electrical machine that can be coupled directly or by means of a transmission to an internal combustion engine, which electrical machine comprises a rotor, a stator, and the stator has at least one phase winding that generates a phase signal.

Background

The rotational angle position and the rotational speed of the crankshaft of an internal combustion engine are important input variables for various functions of an electronic engine control system. In order to determine the rotational speed, markings may be provided on the body that rotates together with the crankshaft of the internal combustion engine at the same angular distance. The marking due to the rotation of the crankshaft can be detected by the sensor and forwarded as an electrical signal to the evaluation electronics.

The electronic device determines a signal registered for the marker for this purpose or measures the time difference between the two markers for the respective rotational angle position of the crankshaft, and can determine the angular velocity and the rotational speed on the basis of the known angular distance of the two markers from one another. In the case of motor vehicles, in particular motorcycles, motorbikes or motorbikes, these markings can be provided, for example, by teeth of metal teeth of a so-called sensor wheel, which, due to their movement, cause a change in the magnetic field in the sensor. The absence of several teeth can be used as a reference mark for identifying the absolute position.

In the case of passenger vehicles (Pkw), 60-2 teeth (60 teeth evenly distributed, with two teeth left empty) are mostly used, while in the case of motorcycles or motorbikes, for example, 36-2, 24-2 or 12-3 teeth are also used. In the case of this indirect principle of the determination of the rotational speed of the crankshaft or of the rotational angle position of the crankshaft, the resolution of the rotational speed signal or the absolute detection of the rotational angle position is determined by the number of teeth and by a reliable identification of the reference markings.

In any modern vehicle with an internal combustion engine, an electrical generator is built which is driven by the rotation of the crankshaft and provides electrical signals which are used to supply the vehicle with electrical energy and to charge the vehicle battery.

The generator is usually designed such that the maximum energy requirement of the onboard power supply system can be provided at any time. This results in: at various operating points of the internal combustion engine, the generator provides more electrical energy than is necessary for charging the battery pack or for supplying the components connected to the vehicle electrical system. In the event of an excess supply of electrical energy at the respective operating point, an overcharge of the battery pack must always be prevented, so that damage to the battery pack is prevented. For this purpose, the generator is often decoupled from other components of the on-board electrical system, wherein a corresponding charging controller is used, by means of which the energy output into the battery pack is prevented, for example by a phase short circuit or by placing the generator in an idle state. In the case of an externally excited electric machine, the electric machine can also be de-excited by means of the control unit, so that it can be put into an idle state. In particular in the case of short-circuit regulation, in which excess electrical energy is converted into heat (and which is the most frequent way of regulation, in particular in the case of motorized bicycles or other light-duty machine cycles), the generator in this case loads the internal combustion engine parasitically, since the electrical energy converted into heat is no longer available as kinetic energy for the driving of the vehicle. A corresponding freewheeling control for the electric machine is generally avoided, since in this case very high voltages can occur, which can lead to damage of the electronic components or to danger to personnel. Corresponding short-circuit regulation is therefore often tolerated, although in this case power losses occur.

Thus, it would be desirable to describe a way to regulate battery voltage in which the power loss is kept as low as possible.

Disclosure of Invention

According to the invention, a method is proposed with the features of patent claim 1. Advantageous embodiments are the subject matter of the dependent claims and the subsequent description.

THE ADVANTAGES OF THE PRESENT INVENTION

In a method for operating a charge controller for an electrical energy store, in particular a battery pack of a vehicle electrical system (which charge controller can be charged with electrical energy by means of an electrical machine which is coupled directly or in a geared manner or can be coupled to an internal combustion engine, which electrical machine comprises a rotor, a stator with at least one phase winding which generates a phase signal), the electrical machine is controlled by the charge controller such that the electrical machine operates as a motor after a first setpoint value of the electrical energy store has been reached or exceeded. Preferably, the internal combustion engine has a rigid coupling with the shaft of the electric machine. This is particularly advantageous since, on the one hand, the position of one of the axes can be inferred in reverse, knowing the position of the other axis. Particularly good torque transmission can also be ensured. If a first setpoint value of the electrical energy accumulator, in particular a first setpoint value of the voltage of the energy accumulator, is exceeded, the electric machine is operated in the manner of an electric motor, whereby the electric energy stored in the battery pack is at least partially converted into kinetic energy, in particular for assisting the internal combustion engine, whereby an overcharging of the battery pack is prevented by the electric machine. In this case, the battery voltage is a particularly good indicator, since it generally saturates when the capacity of the battery is exhausted and can be identified and measured particularly reliably. In this case, the electric motor-driven operation of the electric machine can correspondingly assist the internal combustion engine, which has the following advantages: the energy drawn from the battery pack for voltage regulation is not converted into heat, but into kinetic energy, so that the internal combustion engine is correspondingly relieved of load. This measure has a particularly advantageous effect on the energy balance of the system consisting of internal combustion engine and electric machine, and can help to reduce the fuel consumption of the internal combustion engine.

In a preferred embodiment of the method, after reaching or falling below a further target value of the electrical energy accumulator (which is numerically lower than the first target value), the electric machine is controlled by the charging control unit in such a way that it operates as a generator.

In this case, the first threshold value preferably describes an upper bound and the further setpoint value a lower bound, wherein a setpoint value section is defined by the first and second setpoint values, preferably the voltage value of the electrical energy accumulator, within which the corresponding voltage regulation of the electrical energy accumulator takes place. In this case, the further threshold value defines a lower tolerance limit up to which the electrical energy store is discharged either by means of the electric machine operating in the manner of a motor or by means of other electrical consumers from the on-board electrical system until the electric machine operating in the manner of a generator is restarted. In this case, the electric machine changes into an operating mode, in which energy is extracted from the battery pack during operation in the form of an electric motor, as already described above, and electrical energy is supplied to the electrical energy store during operation of the electric machine in the form of a generator.

Depending on the duration of the individual operating states, an abrupt change between the electric machine operation in the form of a motor and the generator operation may have a perceptible effect for the driver, since the crankshaft is alternately subjected to an additional acceleration or deceleration torque. In order to minimize this effect and to avoid a change in the driver's feel, the torque applied or reduced by the electric machine can be changed continuously by a further preferred embodiment of the method instead of abruptly switching the operating point. For this purpose, the actuation of the electric machine is selected such that the consumed or output electrical power is continuously increased or decreased.

In a further preferred embodiment of the method, the first setpoint value and/or the further setpoint value of the electrical energy accumulator is predefined as a function of the rotational speed of the electric machine. By predetermining the machine parameters for the setting of the setpoint value of the electrical energy store, it is possible to take into account the rotational speed-dependent energy provided in the electrical machine in a particularly simple manner during the charging of the electrical energy store or in the case of the assistance of the internal combustion engine in the form of an electric motor. Further, it is possible to prevent: in the event of an excessively low rotational speed of the electric machine and thus of the internal combustion engine, which is caused by a possible charging requirement for the battery pack, the internal combustion engine is subjected to a deceleration torque too strongly by the electric machine in generator mode operation, so that the operation of the internal combustion engine can be disturbed or even stopped.

In a further preferred embodiment of the method, the first setpoint value and/or the further setpoint value of the electrical energy accumulator is predefined as a function of at least one operating point and/or operating state and/or rotational speed of the internal combustion engine.

In general, a point within a working cycle of the internal combustion engine, in particular of the cylinder, is defined as the working point, wherein a complete working cycle comprises at least one compression and power stroke depending on the internal combustion engine. In this case, the operating state of the internal combustion engine includes a typical running state of the internal combustion engine. These driving states include, in particular: a load state in which the internal combustion engine is permanently subjected to a load; freewheeling, in which the internal combustion engine is driven essentially by an external energy input as a result of the drive train being switched off; or, for example, idling, in which the internal combustion engine is operated substantially without outputting external torque.

The first or second setpoint value can be selected in relation to the operating cycle and the rotational speed of the electric machine or the internal combustion engine, in order to ensure particularly homogeneous operation of the internal combustion engine. In this case, the operation of the electric machine in the form of a motor or in the form of a generator is used in particular to compensate correspondingly for fluctuations of the internal combustion engine due to operation. As a result of the operation of the internal combustion engine, the internal combustion engine always outputs its torque in a pulsed manner, wherein corresponding rotational speed irregularities occur during the operation of the internal combustion engine. This rotational speed irregularity can be compensated for by a corresponding regulation and selection of the setpoint value of the electrical energy accumulator, so that on the one hand a smooth rotational speed fluctuation and on the other hand a corresponding charging control of the electrical energy accumulator can be ensured. The same applies to the operating state of the internal combustion engine, wherein the electric machine can preferably be operated as an electric motor, in particular during load operation, in order to assist the internal combustion engine. Furthermore, for example, in freewheeling, where an external torque input is applied to the internal combustion engine, the external torque input may be used to: as long as the state of charge of the electrical energy store permits this, the kinetic energy obtained in this way is transferred into the electrical energy store by means of the electric machine in the generator mode of operation. At idle, the electric machine can be controlled by the charging controller in such a way that one or more cylinders of the internal combustion engine are correspondingly assisted by the electric motor during the working cycle of the compression stroke, wherein after ignition and expansion of the fuel-air mixture, the generator operation can correspondingly smooth the pulsed torque and the rotational speed increase of the internal combustion engine, so that the kinetic energy obtained in this way can be converted into electrical energy and the electrical energy can be stored in the electrical energy store. In addition to the advantage of a smooth course of the torque and/or rotational speed profile, it is also possible to realize by this operation: the switching between the motor-mode operation and the generator-mode operation of the electric machine takes place without any perceptible influence on the driver.

In a further preferred embodiment, in addition to reducing rotational irregularities within the working cycle of the internal combustion engine, the differentiation between different working cycles can also be compensated for by suitable actuation of the electric machine. In particular, in the case of a small filling quantity of the cylinder, for example when the internal combustion engine is idling, fluctuations in the quality of the combustion can occur. This results in a different and intense speed increase for different working cycles. To compensate for these fluctuations, the electric machine can, in particular, increase the rotational speed of the crankshaft by operating in the manner of a motor if the combustion is less than the average level or decelerate the crankshaft by operating in the manner of a generator if the combustion is more than the average level. As a result, a balancing of the different work cycles with one another can be achieved and a smoother operation of the overall system can be achieved. In the context of these set goals, the electric motor can be correspondingly controlled, or the control method for the electric motor can be correspondingly adapted.

In a further preferred embodiment of the method, at least one value is detected, which occurs once per revolution of the rotor of the electric machine and is associated with at least a rising edge of the phase signal, a falling edge of the phase signal or a zero crossing of the phase signal, wherein after the occurrence of the at least one value the electric machine is operated by the charging controller in the form of a motor or in the form of a generator. By detecting this value in connection with a rising or falling edge of the phase signal having a zero crossing of the phase signal, the rotational angle position of the rotor of the electrical machine or the rotational speed of this rotor can be deduced in reverse. Thus, by the fixed coupling of the electric machine to the crankshaft of the internal combustion engine, it is also possible to determine the crankshaft position from the rotational angle position of the rotor or to determine the rotational speed of the crankshaft from the rotational speed of the rotor. The exact rotational angle position of the rotor or the rotational speed of the rotor can be seen directly from the free-wheeling voltage of the electric machine, depending on the unloaded electric machine, since the relative phase of the free-wheeling voltage corresponds to the rotational angle position of the rotor. In the case of a loaded motor, in particular in the case of a generator-like operation of the motor under load, the exact rotational angle position of the rotor can be determined by additionally taking into account the pole rotor angle. Thus, it is advantageous: prior to the loading of the electric machine in the form of a motor or in the form of a generator, corresponding values are determined, from which the crankshaft position or the rotational speed of the electric machine is determined without this being adversely affected by the corresponding loading of the electric machine. Thus, as a result, it is possible to prevent: the characteristic signal required for determining the rotational speed or the rotational angle position of the rotor is continuously prevented by the voltage regulation of the energy store. In this way, it is possible to separate the voltage regulation from the determination of characteristic values of the phase signal, which are associated with rising and falling edges or zero crossings of the phase signal, in a time-wise manner, so that the voltage regulation and the determination of secondary variables, such as the rotational angle position of the rotor and the rotational speed of the rotor, as a function of the phase signal are obtained, from which the rotational speed of the crankshaft and also the rotational angle position of the crankshaft can also be determined as a result of the direct coupling to the internal combustion engine.

In a further preferred embodiment of the method, the operation of the electrical machine in the form of a motor or in the form of a generator is carried out as a function of at least one rotational angle position of the rotor. As a result of the knowledge of the absolute crankshaft information, the charging controller can advantageously operate the electric machine as a motor or as a generator over a certain crankshaft range. In this way, a still better quality of the high-resolution rotational speed can be provided for functions which require, in particular, a high-resolution rotational speed in a certain crankshaft range, in particular the injection or ignition of an internal combustion engine. In a further preferred embodiment of the method, the motor-or generator-mode operation of the electrical machine is maintained after the occurrence of the at least one value until at least one further value is identified, which is associated with a subsequent rising edge of the phase signal, a falling edge of the phase signal or a zero crossing of the phase signal. In this case, it is advantageous: by identifying a first value which is associated with a rising edge of the phase signal or a falling edge of the phase signal or a zero crossing of the phase signal, a corresponding trigger can be realized, by means of which a determination of the rotational angle position or the rotational speed of the rotor of the electrical machine is determined. In this case, it may be further preferable that: the control intervention of the electric machine for generator-or motor-controlled control of the electric machine is placed between two adjacent values, preferably between two immediately adjacent values. This ensures that: on the one hand, the required charging control of the electrical energy store can be achieved by the electric machine operating in the form of a motor or in the form of a generator; and the corresponding edge or zero crossing identification associated with the respective token value is not disturbed. In this way, a reliable determination of the rotational angle position or rotational speed of the rotor can be ensured.

In a further preferred embodiment of the method, a switching process of the charge controller is initiated for the motor-or generator-mode operation of the electric machine if at least one minimum time interval exists from at least one value associated with a rising edge of the phase signal, a falling edge of the phase signal or a zero crossing of the phase signal.

By using the shortest time interval from the next edge, it can be ensured that: the overall system is no longer in the transient state at the time of the measurement intervention, but rather in the steady state, as a result of which the measurement of the edge or zero crossing can be determined with even greater accuracy and the rotational angle position of the rotor or the rotational speed of the rotor can be determined accordingly with even greater accuracy. Typical minimum time intervals range from about 100 mus to 1 ms.

In a further preferred embodiment of the method, a switching process of the charge controller is introduced after the identification of the value with a time delay for the motor-or generator-mode operation of the electric machine. In this case it is advantageous: the time delay may be used to perform a plausibility check on the values associated with the edges or zero crossings. By this, artifacts in the signal, such as so-called signal jitter, can be excluded. If necessary, this time delay may vary with the rotational speed in order to ensure sufficient calculation time. Typical time delays vary over a time interval of about 100 mus to 1 ms.

In a preferred embodiment of the method, the occurrence of the first value is detected in a first mode on the computing unit, wherein after the detection of the value a change is made from the first mode to a further mode in which the operation of the electric machine is initiated in the form of a motor or in the form of a generator. A direct jump from the first mode to the further mode, the so-called Interrupt (Interrupt), offers the following advantages: switching along as much as possible synchronization can be achieved. This ensures a reliable settling time to the next edge, and at the same time the implementation in the computing unit is computationally efficient.

In a further preferred embodiment of the method, the electric machine is operated by the charging controller in a clocked manner, for motor-or generator-mode operation of the electric machine, preferably in a clocked manner after the occurrence of the at least one value, preferably by means of Pulse Width Modulation (PWM). The timed control of the electric machine by the charging control unit is advantageous, since the desired target voltage of the electrical energy accumulator can be reliably set. By means of a corresponding adaptation of the pulse width or of the time start and of the end thereof, the energy supply or the energy extraction from the battery pack can be adapted to the current actual situation (state of charge of the battery pack, operating conditions of the internal combustion engine, use of electrical components in the vehicle electrical system, etc.) as good as possible in the selection of the control mode (generator-like or motor-like). Furthermore, the generator-or motor-loaded corresponding clock of the electric machine can be reliably placed between the respective trigger values for determining the rotational angle position or rotational speed of the electric machine, so that on the one hand a reliable charging control and on the other hand an exact identification of the edges and accordingly a reliable determination of the rotational speed or rotational angle position of the rotor can always be ensured.

In a further preferred embodiment of the method, the time control is selected such that the operating voltage of the electrical energy accumulator lies between the first setpoint value and the further setpoint value, preferably at a constant value. The operating voltage of the electrical energy store can be set almost arbitrarily by a corresponding selection of the clock frequency, which is typically 10, 20 or 100kHZ, and a corresponding pulse width of the control signal, in particular of the pulse-width-modulated signal, and/or a selection of the temporal start and/or end point of these pulse widths. On the other hand, the positions of the pulses may be selected such that there is no temporal overlap with the characteristic values of the phase signals that are necessary for determining the respective rising and falling edges of the respective phase signals. In addition, the time constant of the pulse width modulated regulation is usually significantly smaller than the time constant of the motor. The point in time of the switching in connection with the determination of the respective value is thereby no longer of great importance, and it is not necessary for the switching process to take care of the phase signal.

It is further advantageous that: the clocked generator-wise and/or motor-wise loaded clock frequency of the electric machine lies outside the human auditory spectrum. In this case, frequencies greater than 50kHz are particularly preferred.

In a further preferred embodiment of the invention, at least one phase signal of the electric machine is processed by means of an electronic circuit, in particular an engine control device. By corresponding processing and regulation of the phase signal or of the value associated with the phase signal and of the associated rising, falling and zero crossing of the phase signal, in particular the charging control of the electrical energy accumulator in the engine control unit, an additional control component can be dispensed with, since the engine control unit is always present and can in principle also be used for this application. This is advantageous, since the corresponding control architecture can be simplified thereby, whereby additional costs can be saved.

In principle, it is easy to understand that: by the method described above, not only can a particularly energy-efficient voltage regulation of the electrical energy store be achieved, but a high-resolution rotational angle position or rotational speed of the rotor can also be determined directly from the internal signal of the electric machine, but also, due to the fixed coupling of the rotor of the electric machine to the crankshaft of the internal combustion engine, with a correspondingly high degree of accuracy. In principle, therefore, the corresponding sensor wheel and the sensor device arranged thereon for determining the rotational angle position or the rotational speed of the rotor can be dispensed with. The determination of the rotational angle position or the rotational speed of the rotor is always possible when the electric machine or the internal combustion engine is running, since the corresponding charging control of the electrical energy accumulator is separated in time from the determination of the edges or zero crossings of the phase signal, which are necessary for determining the rotational angle position or the rotational speed. In this way, costs can be saved, which is advantageous in particular with regard to a less expensive two-wheeled or lightweight motor cycle operated by means of an electric motor. It is also possible to significantly improve control functions such as fuel injection position calculation, torque calculation, or learning functions for accurately determining the OT position, and the like.

In a further preferred embodiment of the method, the rotational angle position or the rotational speed of the rotor or the crankshaft is used for controlling the internal combustion engine. The detection and processing of the phase signals of the electric machine by the engine control device and the corresponding determination of the rotational angle position or rotational speed of the crankshaft as a function of the rotational angle position of the rotor and the possible angular offset that exists due to the pole rotor angle can be used correspondingly in the control device of the internal combustion engine to control the ignition time or torque of the internal combustion engine. Therefore, the charging control of the battery pack, the control of the internal combustion engine, and the improved determination of the rotational angular position or rotational speed of the crankshaft can be combined in the engine control apparatus, thereby obtaining a further synergistic effect. For this purpose, the computing unit used, which is preferably designed as an engine control device for an internal combustion engine, has a corresponding integrated circuit and/or a computer program stored on a memory, which is/are set up to carry out the method steps described above.

It is advantageous to implement the method or to provide an integrated circuit, in particular an ASIC (application specific integrated circuit), in the form of a computer program which is preferably stored in the form of software on a data carrier, in particular a memory, and is available in the computing unit for implementation of the method, since this results in particularly low costs, in particular when the control device to be implemented is also used for other tasks and thus always already exists. Data carriers suitable for providing the computer program are, in particular, magnetic memories, optical memories and electronic memories, as are often known from the prior art.

The preferred electric machine, which is operated in the manner of a motor and/or in the manner of a generator by means of the method described above, has a converter with active switching elements, preferably transistors, in particular MOSFETs (metal oxide semiconductor field effect transistors), so that the motor or generator operation of the electric machine can be effected not only by actuation of the charging controller or by actuation of further higher-level control devices by corresponding connections of these transistors.

Due to the possibility of also operating the electric machine in the manner of a motor, further functions of the overall system can be achieved. In particular in the case of small single-cylinder internal combustion engines, a low torque is often provided for low rotational speeds, in particular the idling rotational speed of the internal combustion engine. If the internal combustion engine is assisted by the electric machine operating as an electric motor when starting from a standstill, a significant improvement in the starting behavior can be achieved and the driving comfort or the driving pleasure of the driver can thereby be increased.

The function of the starter can be achieved by the electric machine in motor mode operation if the electric machine is capable of supplying a sufficiently high torque for low rotational speeds. In this way, starter components can be saved and system costs and installation space can be reduced thereby. Given a corresponding implementation of the drive train, the electric machine can be used to assist the driver in driving the vehicle when operating in the form of an electric motor.

During a switching process in a gearbox, the shaft to the internal combustion engine is usually decoupled by means of a clutch. After a shift into a new gear, there is usually a rotational speed difference between the clutch half on the transmission side and the clutch half on the engine side before the clutch is closed. This rotational speed difference is compensated for during the closing process by the friction between the two clutch halves. The wear of the clutch disk associated therewith can be reduced if the rotational speed of the crankshaft and thus of the clutch half-section on the engine side is compensated for or brought close to the transmission side in order to synchronize the auxiliary rotational speed of the electric machine. For this reason, the engine speed must be reduced when shifting to a higher gear. This applies in relation to the rotational speed level of the previous gear. For this purpose, the electric machine can be used as a generator in a braked manner, if necessary.

Conversely, if shifting to a lower gear, the engine speed must be increased. For this purpose, the electric machine can be used as an auxiliary in the form of an electric motor.

In a further preferred embodiment of the method, information about traffic conditions and/or travel paths occurring in the near future is taken into account for the planning of the switching points in time between the electric machine operation in the form of a motor and the generator operation and for the planning of the state of charge of the electrical energy store. This information can be obtained from the corresponding map and information about the current location and from current traffic information in the vicinity, which is received by means of suitable communication means.

Further embodiments of the invention emerge from the description which follows and the accompanying drawings.

Drawings

Fig. 1 shows a schematic representation of a sensor wheel according to the prior art with sensors, in particular for rotational speed determination;

fig. 2a to c show schematic diagrams (a, b) of an electric machine coupled to an internal combustion engine and the associated signal waveforms (c);

fig. 3 schematically shows an electric machine with corresponding associated phase signals;

fig. 4a and 4b show possible voltage waveforms for the phases of a three-phase motor;

fig. 5a and 5b show a simplified equivalent circuit diagram (a) of a single phase of the electric machine and an associated vector diagram (b) of the phase voltage vectors; while

Fig. 6a to 6d show possible switching states of the electric machine and various alternative control methods for the generator-wise and/or motor-wise control of the electric machine.

Detailed Description

Fig. 1 schematically shows a sensor wheel 20 and an associated inductive sensor 10, as it is used in the prior art for rotational speed determination or for approximate determination of the rotational angle position of a crankshaft. In this case, the sensor wheel 20 is fixedly connected to the crankshaft of the internal combustion engine and the sensor 10 is mounted in a stationary manner in a suitable location.

The sensor wheel 20, typically a sensor wheel 20 made of ferromagnetic material, has teeth 22 which are arranged on the outside with a space 21 between two teeth 22. At a point on this outer side, the sensor wheel 20 has a recess 23 over the length of a predetermined number of teeth.

This recess 23 serves as a reference mark for identifying the absolute position of the sensor wheel 20.

The sensor 10 has a bar magnet 11 on which a soft magnetic pole pin 12 is mounted. The soft pole pin 12 is in turn surrounded by an induction coil 13. As the sensor wheel rotates, the teeth 22 and the gaps between two respective teeth alternately pass the induction coil 13 of the sensor 10. Since the sensor wheel and therefore also the teeth 22 consist of ferromagnetic material, a signal is induced in the coil during rotation, with which a distinction can be made between the teeth 22 and the recesses.

By correlating the time difference between two teeth with the angle enclosed by the two teeth, the angular speed or rotational speed of the crankshaft and, in addition, the corresponding angular position of the crankshaft can be approximated.

At the gap 23, the signal induced in the induction coil has a different waveform than at the teeth 22 that would otherwise alternate with the gap. In this way, absolute position marking is possible, however only with respect to one full revolution of the crankshaft.

Fig. 2a shows an internal combustion engine 112 to which the electric machine 30 is directly or via a transmission coupling, wherein the electric machine 30 is driven by a crankshaft 17' of the internal combustion engine 112. Thus, the rotational speed n of the motor 130_GenAnd the rotational speed n of the crankshaft 17_BKMAnd the angular position α of the rotor of the motor 30₁And the rotational angle position α of the crankshaft 17' have a fixed relationship with one another, the electric machine 30 is also assigned a charging controller L R, which supplies the battery B within the on-board electrical system 110 with energy depending on the still remaining capacity of the battery B, a computing unit is also provided, in particular an engine control device 122, which exchanges data with the electric machine 30 or with the internal combustion engine 112 via a communication connection 124 and is set up to operate the internal combustion engine 112 and the electric machine 30 accordingly.

In fig. 2b, the motor 30 is again schematically shown in an enlarged form. The motor 30 has: a rotor 32 with a shaft 17, the rotor having field windings; and a stator 33 having stator windings. This therefore relates to separately excited electrical machines, as are customary in motor vehicles in particular. However, especially for motor-driven vehicles, especially in the case of small and lightweight motor-driven vehicles, motors with permanent magnets, that is to say permanent magnet motors, are mostly used. Within the scope of the invention, in principle, both types of electric machines can be used, wherein in particular the method according to the invention does not depend on the use of a corresponding type of electric machine, permanent magnet or separately excited.

The electric machine 30 is designed as a three-phase generator, in which three phase voltage signals are induced, which are phase-shifted by 120 ° with respect to one another. Such three-phase generators are usually used as generators in modern motor vehicles and are suitable for carrying out the method according to the invention. Within the scope of the invention, in principle, all electric machines can be used, independently of their number of phases, wherein in particular the method according to the invention does not depend on the use of a corresponding type of electric machine.

The three phases of the three-phase generator 30 are represented by U, V, W. The phase U, V, W is connected to the first path 34, which has a transistor T for each phase U, V, W, respectively, and to the second path 35_HThe second path having a further transistor T for each phase U, V, W respectively_L. Corresponding transistor T_H、T_LIn each case, control unit 40 in the form of charge controller L R can be acted upon correspondingly in such a way that, in a first operating situation, a phase voltage U can be induced_U、U_V、U_WOr in another operating case the electric machine can be operated as a motor. Charging control of battery B within on-board electrical system 110 is effected by a desired changeover between generator-wise operation of electric machine 30, in which electrical energy is supplied to battery B, and motor-wise operation of electric machine 30, in which electrical energy is extracted from battery B.

Fig. 2c shows three graphs, which show the associated voltage waveforms with respect to the rotational angle of the rotor 32 of the electric machine 30. In the upper diagram, the voltage waveform at phase U, V, W and the associated phase voltage U are plotted_P. It is generally easy to understand that: the numerical sum value ranges illustrated in this diagram and in the subsequent diagrams are merely exemplary and thus do not limit the invention in principle. It is also easy to understand that: the generator is an electric machine 30 in generator mode operation.

In the middle diagram, the generator voltage U is shown_GThe generator voltage is formed by the envelope of the positive and negative half waves of the voltage waveform U, V, W.

Finally, in the lower diagram, the rectified generator voltage U is shown_G-(see fig. 2 a) together with the generator voltage U_G-Effective value of (U)_GeffThe generator voltage is attached between B + and B-.

In fig. 3, the stator 33 with the phase U, V, W from fig. 2b is schematically shown, together with the transistors T of the first path 34 and the further path 35_H、T_L. Depicted as transistor T_H、T_LThe rectifier element in form is preferably configured as a MOSFET (metal oxide semiconductor field effect transistor). These MOSFETs have particularly low power losses. The nomenclature used hereinafter for the voltages and currents that occur is also shown.

Alternatively, U_U、U_V、U_WThe phase voltages of associated phase U, V, W are shown, as they fall between the phase lines and the star point of stator 33. U shape_UV、U_VW、U_WUWhich represents the voltage between two phases or the associated phase lines of these two phases.

I_U、I_V、I_WShowing phase currents from the corresponding phase line of phase U, V, W to the star point. I represents the total current of all phases after rectification.

Now, three phase voltages U with potential B-are shown in FIG. 4a in three graphs with respect to time_U、U_V、U_WAs they occur in generators having an outer pole rotor with six permanent magnets. The illustration of an electrical machine 30 with three-phase stator windings 33 is to be seen merely as an example, wherein the method according to the invention can in principle also be implemented on generators with a correspondingly sufficient number of phases or permanent magnets or field coils, without limiting the generality. Likewise, instead of star-connection of the stator coils, delta-connection or other connection methods can also be selected.

In the case of an electric machine 30 with current output, the phase voltage U is the phase voltage_U、U_V、U_WThe waveform of (a) is approximated to a rectangle at one level. This is indicated in particular by the following: due to the generator voltage, either the positive diode or the negative diode is conducting in the conducting direction, and thus either approximately 15-16 volts (battery charging voltage at 12V lead-acid battery and voltage across the positive diode) or negative 0.7-1 volts (voltage across the negative diode) is measured. The measured reference potentials are respectively grounded. Other reference potentials, such as star point of the stator, may also be selected. These reference potentials result in alternating signal waveforms, but do not change the analyzable information, the acquisition and analysis of this information.

In principle, phase signal (U)_U、U_V、U_W、I_U、I_V、I_W) May be obtained in different ways. For example, it is possible that: determining phase voltages (U) relative to each other_UV、U_VW、U_WU) (ii) a As long as the stator of the electric machine is star-connected with a measurable star point, the phase voltage is determined by the diodes of the connected rectifier relative to the output terminals (B +, B-) of the rectifier; taking into account the output voltage (U) of the branch with respect to the star point_U、U_V、U_W) (ii) a Or similarly analyze the phase currents.

In fig. 4b, the phase voltage U from fig. 4a is plotted together in a diagram_U、U_V、U_W. In this case, a uniform phase shift is clearly visible.

The voltage signal is repeated six times by six magnets, in particular permanent magnets, so-called pole pairs, during one full revolution of the rotor 32 of the electrical machine 30. Correspondingly, for each revolution of the rotor 32, each phase, i.e. each phase voltage U_U、U_V、U_WSix falling edges F L occur_DAnd six rising edges F L_U(F L for the corresponding phase)_UU、FL_VU、FL_WUAnd F L_UD、FL_VD、FL_WD）。

These edges define angular segments, i.e. exactly the angular segments covered by the magnets in the radial direction of the stator, therefore, knowing the absolute reference point per revolution, it is possible to determine the corresponding edge F L_UOr F L_DFor example, the reference point is characterized by a reference magnet having a phase voltage U_U、U_V、U_WDifferent from other magnets.

Now, with suitable means, not only the falling edge F L can be identified_DAnd can recognize rising edge F L_UThe required triggers can either be integrated in the control device or in the control electronics, for example the control device, the controller for the battery pack voltage and/or in the case of an active rectifier in the respective generator controller, or can also be assigned externally to the generator controller, the respective TT L signals can be transmitted in particular for the case of the use of the control device, in particular the engine control device 122 (see fig. 2 a), by way of individual lines or by way of a preceding combined electronics or in other manner suitably in combination via only one data line 124 (see fig. 2 a).

In FIG. 4b, the phase voltage U_U、U_V、U_WRespectively assigned with the value W_U、W_V、W_WThese values are also referred to as W_Ud、W_Vd、W_WdLikewise, rising edge F L may also be given_UAssign the corresponding value W_Uu、W_Vu、W_Wu. The zero crossing of the phase voltage may also be assigned a corresponding value W_U0、W_V0、W_W0These values may be used to identify the rotational angle position α of the rotor 32₁Or angular increments specified by pole pairs of the stator 33, the angular position α of the rotor 32 depending on the plateau region of the phase signal or other region therebetween₁Is also possible. Again, this is trueThese values may also be used to depend on the time difference Δ t₁、Δt₂、Δt₃To determine the rotational speed of the generator.

In this case, with a uniform arrangement of six permanent magnets in the electric machine 30, a total of 18 falling edges F L d and thus 18 associated values occur at equal intervals from one another for each revolution₁、Δt₂Or Δ t₃During this, the angle 360 °/18 = 20 ° is covered, which, as already mentioned at the outset, can also be used to detect the angular position α of the rotor 32 of rotation₁The exemplary determined 20 ° is the detectable angle increment. Furthermore, from this, the angular velocity ω can also be determined_i. The angular velocity is based on ω_i= 20°/Δt_iTo obtain and associated rotational speed n_iAccording to n_i=ω_i60 s/min/360 DEG is obtained in revolutions per minute.

In principle, it is readily understood that the alternative is to fall edge F L_DThe rising edge can also be used for determining the angular position α of the rotor 32₁And for determining the instantaneous speed n of the electric machine 30_GenCorrespondingly, the number of values per revolution is doubled, so that not only the rotational angular position α of the rotor 32 is obtained₁And the rotational speed n_GenMoreover, the edges of these phases can be analyzed in a number of other ways and methods, for example by the rising edge of the respectively identical or corresponding phase F L_UAnd a falling edge F L_DAt intervals from each other or by rising edges F L of the same or all phases together_UOr falling edge F L_DTime intervals of the time interval.

Except for rising edge F L_UAnd a falling edge F L_DIn addition, for the rotational angle position α of the rotor 32₁Determination or rotational speed identification n_GenMay also be used with improved resolution of the phase signal U_U、U_V、U_WZero crossing of (c).

Actual rotational angular position α of rotor 32 and its shaft 17₁And thus the rotational angular position α of the crankshaft 17' can only be determined by the motor 30Electrical signal, in particular phase signal U_U、U_V、U_WOr associated phase current I_U、I_V、I_WThe accuracy is determined to be insufficient, since in the case of a motor 30 which is loaded by the passage of current, this occurs in the phase signal U_U、U_V、U_WOr I_U、I_V、I_WIs in phase with the actual rotational angular position α of the rotor 32₁The angular offset between is a systematic error in the form of. This is further illustrated in subsequent figures.

Fig. 5a shows a schematic diagram of a simplified equivalent circuit diagram of a single phase of the electric machine, while fig. 5b shows the respective voltages or currents and their relative phase shifts from one another in a vector diagram in a corresponding manner. In principle, the knowledge determined from this single-phase equivalent circuit diagram can also be transferred to a polyphase machine, as it is shown, for example, in the above description. From the single-phase equivalent circuit diagram of the electric machine in fig. 5a) and the associated vector diagram shown in fig. 5b), a voltage equation for the loaded electric machine can be derived, which is as follows:

U_p= jX * I + u，

where U corresponds to the output voltage of the motor 30, U_PCorresponding to the idling voltage of the motor without load and I jX corresponding to the voltage drop U_XThis voltage drop falls in the generator due to the through current flowing through the motor and due to the reactance X of the motor.

In this case, the idling voltage U of the motor 30_PCorresponds to an ideal induced voltage which corresponds to the phase-related rotational angular position α of the rotor 32₁And (5) the consistency is achieved. In this case, the angular offset θ corresponding to the pole rotor angle is correspondingly equal to zero. Therefore, the idling voltage U_PAccurately reflects the geometric motion of the rotor 32 and thus describes the precise angular position of the rotor (in the unloaded state of the motor 30).

The output voltage of the generator 30 subjected to the load is determined by the load of the electric machine 30 and the resulting current IU with respect to the induced idling voltage U of the generator_PIn which between U and U_PThe angular offset between them is obtained by the angular offset θ, the so-called pole rotor angle. In principle, this angular offset can be calculated from the coil current I and is difficult to calculate without knowing the coil current I.

Furthermore, the angle between the output voltage U and the current I is obtained by the connected load and is phi = 0 ° for a purely ohmic load. Ideal induced voltage (free-wheeling voltage) U of the motor_PObtained as the product of the motor constant, the excitation and the angular velocity. In the case of permanent magnet machines, a constant excitation is obtained by the permanent magnets used and thereby the ideal induced voltage, which is proportional to the angular velocity. Thus, from the vector diagram in fig. 5b), for the angular offset θ:

(cos(θ) = (U + sin(φ) * X * I)/U_P。

using a voltage regulator 40 operating linearly (such as that shown in fig. 3) and in the linear range (triode range) for the transistor T_H、T_LCan be regulated to be almost constant (relative to the battery voltage) in the case of a manipulation of at least one of the transistors of the motor 30. Furthermore, even if small capacitances may occur in the on-board electrical system, the use of converters as rectifiers 34, 35 in generator mode operation of the electric machine 30 together with the downstream electrical energy store S in the form of a battery B also leads to approximately a purely ohmic load at the output of the generator 30. Thereby, the angular offset Φ between the output voltage U and the current I becomes 0, wherein the addend (sin (Φ) × I) in the aforementioned formula also becomes 0 and thereby disappears.

In principle, the free-wheeling voltage U_PWith the speed n of the motor 30_GenAnd (4) in proportion. Thus, assuming that the amplitude of the output voltage U is substantially constant and assuming that Φ becomes zero and thus the second addend disappears, the aforementioned formula is simplified to the following relationship:

θ_aprox= cos^-1(const./n_Gen)，

wherein the constant const is substantially based on the constant output voltage U and the free-wheeling voltage U_PAnd thereby with the rotational speed n_GenIndependent components.

If chosen according to the edge time t_GenInstead of the speed n_GenTo present for theta_aproxThe formula of (b) then yields theta_aproxAnd t_GenThe following relationships:

θ_aprox= cos^-1(const.' * t_Gen)，

wherein const.' includes, in addition to the above constant factor, a constant factor for a rotational speed n in revolutions per minute (rpm)_GenTo calculate the edge time t in seconds_GenIs constant factor (c).

In the time range of importance for a typical internal combustion engine from idle to approximately 15000rpm, this relationship can be approximately described by a straight-line equation with a negative slope and thus enables high computational efficiency in the application. As already indicated at the outset, the stated value ranges are merely illustrative and should not be limiting for the invention.

In the case of such a design in which the battery pack regulation or a corresponding regulation of the battery pack voltage is such that the corresponding actuator 42 operates in the linear range, the angular offset θ can also be estimated sufficiently accurately, in a first approximation, without knowledge of the current I flowing through, which permits a very reliable determination of the phase voltage U at the phase voltage U_U、U_V、U_WIs in phase with the actual rotational angular position α of the rotor 32₁The angular offset theta therebetween.

Therefore, according to the phase voltage U_U、U_V、U_WTo determine the rotational angular position α of the rotor 32_PhaseCan correspondingly depend on the corresponding rotation speed n_GenAccording to which the actual rotational angular position α of the crankshaft 17 of the internal combustion engine or the rotational angular position α of the rotor 32 can be correspondingly determined₁. With a fixed coupling between the shaft of the rotor 32 and the crankshaft 17, these two rotational angle positions are coupled to one anotherThus, without limiting generality, α = α applies₁But once current flows through, α₁Can no longer be present at phase signal U_U、U_V、U_W、I_U、I_V、I_WIs seen therein.

By means of phase signals U_U、U_V、U_W、I_U、I_V、I_WRelative to an uncorrected rotational angular position α_PhaseThe corresponding determination of (a) and the previously described determination of the pole rotor angle θ may be made by:

α₁≈ α_Phase+ θ

determining the actual angular position α with a particularly good approximation₁。

However, the previously made method for determining the rotational angle position α of the rotor 32 with high accuracy₁Or the speed n, is assumed to be: in determining the corresponding phase signal U_U、U_V、U_W、I_U、I_V、I_WWithout intervention by the charging controller 40 in regulating the voltage of the electrical accumulator S during the time frame.

In fig. 6a, different permissible switching states of the input and/or output of the electric machine 30 with three phases U, V, W can be seen. States V1 to V6 describe states in which a current flow exists between the electric machine 30 and the electrical energy accumulator B, i.e. the electrical energy accumulator B is charged by the electric machine 30 during generator mode operation or the electrical energy accumulator B feeds the electric machine 30 during motor mode operation.

The states V7 and V8 describe states in which there is no passing current between the motor 30 and the electrical accumulator B. In other words, the three phases are short-circuited with respect to each other. The three-digit numbers in parentheses after the state relation, i.e., 1 and 0, represent the switching states in which the respective phases are located. The first digit represents phase U, the second digit represents phase V and the third digit represents phase W. 1 denotes that the phase is connected to the positive input/output of the electrical energy store via the corresponding switch of the inverter, and 0 denotes that there is a connection to the negative input/output of the electrical energy store.

State V1 exists, for example, when phases U and W are connected to the positive input/output of the electrical accumulator and phase V is connected to the negative input/output of the electrical accumulator. The corresponding case applies to the other states V2 to V6. The state V7 represents a state in which the motor is short-circuited through the three lower switches of the inverter, and V8 represents a state in which the three phases are short-circuited through the upper switches of the inverter.

If the states of these phases are selected such that the illustrated states V1 to V6 are switched periodically and continuously before the rotor (rotor position RP) is positioned in the rotational direction, the motor 30 is operated in a motor manner. The angle between the adjusted switching state and the rotor position RP is referred to as the pole rotor angle or the load angle and is θ_MAre depicted.

If the switching state of the rotor position RP lags behind in time in the direction of rotation, there is operation in the manner of a generator. In this case, the pole rotor angle occurs with opposite sign, here as θ_GAre depicted.

If only states V1 to V6 in periodic sequence are selected as switching states, this is referred to as block commutation in the selected steering method. The voltage at the phase connection is predetermined by the voltage of the electrical energy accumulator.

Fig. 6b shows an extension of the control method for setting the electrical power. If maximum power should not be called up (motor-wise or generator-wise) for an operating point set by the pole rotor angle θ and the rotational speed (and in the case of separately excited machines by excitation), a change can be made in rapid succession between the desired switching state V1 to V6 (here, by way of example, V2) and one of the two short-circuit states V7 or V8 (here, by way of example, V7). In this case, during generator operation, the electric machine 30 is partially operated in a short circuit (state V7) and thus prevents the passage of current into the electrical energy store B during this time; during this time, during operation in the form of a motor, the current flow from the electrical energy store B into the electric machine 30 is prevented.

At this operating point of the electric machine, the resulting manoeuvreVector V2_PWMDepending on the time t during which a current flow between the electric machine and the electrical energy store is present_onThe sum of the durations of the two switching states (t)_on+ t_off) And the length of the vector of switching state V2 (defined by the voltage available for matching):

a fast transition between these two switching states can be achieved by means of pulse width modulation PWM.

The decision whether to select the switching state V7 or V8 to set the length of the resulting switching vector may be made depending on the desired switching process of the switches of the inverter. It is appropriate for the switching states V2, V4 and V6 to be selected in combination with the switching state V7, since only one phase has to be switched from 1 to 0 and vice versa from 0 to 1.

While for the switching states V1, V3 and V5 a combination with the switching state V8 is suitable, since only one phase has to be switched from 0 to 1 and vice versa from 1 to 0.

It is preferable that: it is necessary to operate as few switches T as possible of the inverters 34, 35 simultaneously_H、T_LIn order to distribute the switching losses occurring in these switches over time and in this way to achieve a more cost-effective cooling. On the other hand, all switches T cannot be ensured due to component tolerances and other influences_H、T_LThe switching is performed exactly simultaneously. Thus, a small number of simultaneous switching processes suppress high-frequency signal components which may be caused by high-frequency switching due to different switching delays.

Fig. 6c shows another steering method, which is referred to as space vector modulation. This further actuation method results if not only the switching states V1 to V6 (here, by way of example, V2 and V3) and the short-circuit state V7 or V8 are periodically changed, but also intermediate states between V2 and V3 can be set.

The position of the possible switching states in the first two methods (shown by the arrows between the centers (V7, V8) and the points V1 to V6) is limited and consequently a constant pole rotor angle (but a pole rotor angle that fluctuates periodically in time) cannot also be set, while a significantly more constant setting of the pole rotor angle θ can be achieved using the intermediate states.

It is possible to adjust intermediate states in which the method of PWM switching between the two switching states V1 to V6 or V7 or V8 is extended by the third switching states V1 to V6, wherein the first switching states V1 to V6 and the third switching states V1 to V6 are not identical and are periodically adjacent to one another.

The relationship between the time at which the first switching state V2 is present and the time at which the third switching state V3 is present defines the position of the resulting intermediate switching state between these two switching states, i.e., V2 and V3. By the duration of the second switching state V7 or V8, the vector length and thereby the power at the operating point can be adjusted.

In the case of a continuously changing duration of the three switching states, a resulting steering vector SZ can be realized, the tip of which moves on a circle around the center. By means of two vectors SZ of these switching states_M1And SZ_M2And the desired resulting switching vector to calculate the corresponding time duration.

As shown in FIG. 6b, vector SZ_M1And SZ_M2By a transformation between V2 and V7 or by a transformation between V3 and V8. As in the previous control method, the positioning of the vector in the direction of rotation before or after the rotor position with respect to the rotor position (with the pole rotor angle in between) illustrates: an operating mode, i.e. in the form of an electric motor or in the form of a generator; and an operating point of the electric machine for the selected or current rotational speed.

In order to have to operate as few switches as possible of the inverter at the same time and to achieve the advantages listed above resulting therefrom, a switching sequence V7-V2-V3-V8-V8-V3-V2-V7 is suitable in this example.

In fig. 6d is shown: how an efficient voltage regulator design (achieved by switching between motoring and motoring of the machine) can be assisted in the space vector approach by high frequency switching.

Instead of adjusting the angle theta of the rotor having poles over a longer period of time_MIn the motor mode or with a pole rotor angle theta_GThe generator mode of (2) may also be switched between these states at high frequencies. The relationship between the two durations of these states remains unchanged, only the respective duration being greatly reduced. For example, the plotted rotor position RP is assumed. The resulting switching vector SZ is required to achieve the desired motor or generator operation_MSwitching vector SZ for motor operation or demand_GFor generator operation. The direction of rotation of the rotor should be in the clockwise direction without limiting generality.

If the resulting intermediate control vector SZ is calculated from the relationship between the duration of the motor-mode operation and the duration of the generator-mode operation_resThe voltage regulator operation can be simplified to have the resulting pole rotor angle θ_resIs operated in a motor mode.

Alternatively, it is possible to operate according to the switching vector SZ_MAnd SZ_GAnd the two-pole rotor angle theta with the sign taken into account_MAnd theta_GTo calculate the resulting vector. If SZM and SZG have different vector lengths, then, for example, the average of the two vector lengths may be selected as an approximation of the resulting vector length.