Method for recovering information of a space vector control, method for operating an inverter, demodulator device, control device and converter device

Abstract

A method for recovering information from a space vector control is described, the method comprising a step of determining a duty cycle of an input signal (202) using the input signal (202), the input signal (202) representing a signal pulse-width modulated using a space vector, and a step of determining a rotational speed (210) and a modulation degree (212) of the space vector using the duty cycle (604).

Description

[0001] The present invention relates to a method for recovering information from a space vector control system, a method for operating an inverter, a demodulator device, a control device and a converter device, as well as an electric axle drive and a motor vehicle.

[0002] Controlled drives generally consist of a control unit, an inverter, and an electric motor. The control unit comprises a microcontroller, which typically implements the control circuitry for the electric motor as well as a PWM driver for modulation methods for the inverter. Asynchronous PWM methods are frequently used (e.g., space vector modulation, sine-triangle modulation). PWM stands for pulse duration modulation, which can also be referred to as pulse width modulation. Alternatively, synchronous PWM methods are based on pulse patterns optimized with respect to a criterion, usually low electric motor losses, and are referred to as optimized pulse patterns (OPP). A switching mechanism between asynchronous and synchronous modulation is disclosed in DE 10 2017 204 106 A1.A velocity and position estimation device in which phase currents are measured and voltage vectors are evaluated is described in WO 2022 / 272 158 A1 and DE 10 2022 203 427 A1.

[0003] Against this background, the present invention provides an improved method for recovering information from a space vector control system, an improved method for operating an inverter, an improved demodulator device, an improved control device, and an improved converter device, as well as an improved electric axle drive and an improved motor vehicle according to the main claims. Advantageous embodiments are described in the dependent claims and the following description.

[0004] The presented approach offers a way to reduce machine and inverter losses when using asynchronous PWM methods alone. Combined PWM methods can advantageously reduce memory requirements as well as microcontroller and software architecture demands.

[0005] A method for recovering information from a space vector control system is presented. The method comprises a step of determining the duty cycle of an input signal using the input signal, where the input signal represents a pulse-period-modulated signal using a space vector, and a step of determining the rotational speed and modulation level of the space vector using the duty cycle.

[0006] The method can advantageously be used in conjunction with an inverter. Thus, the input signal can be suitable for operating an inverter, for example, to convert a DC voltage into an AC voltage to drive an electric motor. However, the method can also be applied to other devices or systems. Advantageously, the method can be used for plug-in solutions, for example, in the form of a chip, and integrated into an existing system. Advantageously, demodulation can be performed independently of a pulse-width modulated frequency and is therefore resource-efficient. This means that the required values ​​or quantities can be advantageously derived from existing information.

[0007] The input signal can be shaped to operate an inverter using an asynchronous PWM method. For example, the input signal can be a signal modulated using space vector modulation or sine-triangle modulation. The duty cycle can represent a duty ratio or correspond to the duty cycle. The duty cycle can be determined as the quotient of the duration of a high level during a current period of the input signal and the duration of the input signal's period. The duty cycle can be recalculated for each period, allowing for continuous determination of current values ​​for the rotational speed and the modulation level of the space vector. Using the rotational speed and the modulation level of the space vector, a signal can be generated to operate the inverter using a synchronous PWM method.In synchronous PWM, the number of switching pulses per period is predefined, resulting in comparatively low switching losses in the inverter. The switching pulses are synchronized with the rotor angle of the electric machine, and the electrical frequency of the synchronously modulated signal is synchronized with the rotor speed. Synchronous PWM methods are usually combined with asynchronous PWM methods, as the latter are advantageous for low speed ranges. Asynchronous and synchronous PWM methods can advantageously be implemented in a switchable manner. The approach described here allows both methods to be implemented while minimizing memory requirements, microcontroller (CPU + FPGA or CPU + Advanced Timing Unit), and software architecture requirements.

[0008] In the determination step, the duration of the high level and the period of the input signal can be easily recorded using at least one counter. Using two counters, both can be reset, for example, on a rising edge of the input signal. One counter can then count from the rising edge to the next falling edge, and the other counter can count from the rising edge to the next rising edge. In this way, the duty cycle can be determined very easily.

[0009] According to one embodiment, the rotational speed can be determined using a Clarke transformation during the determination step. Advantageously, this allows multiphase quantities, for example in a three-phase machine, to be transformed into a simpler two-axis coordinate system.

[0010] The input signal can represent a three-phase signal. In the determination step, the first duty cycle of the first phase of the input signal, the second duty cycle of the second phase of the input signal, and the third duty cycle of the third phase of the input signal can be determined. In the analysis step, the rotational speed and modulation level of the space vector can be determined using the first, second, and third duty cycles. The three phases can be designated as phases U, V, and W. Thus, the respective duty cycle for each phase can be continuously determined for the current period. This means that the space vector can advantageously be determined using the three duty cycles.

[0011] Furthermore, a method for operating an inverter in a first operating state and in a second operating state is presented, the method comprising the following steps: Reading in an input signal that represents a pulse-duration modulated signal asynchronously using a space pointer; Determining a rotational speed and modulation level of the space vector of the input signal using a method in a previously mentioned variant; Outputting the input signal to an interface with the inverter in order to operate the inverter in its initial operating state; Creating a synchronously pulse-duration modulated signal using the rotation speed and modulation level; and Outputting the synchronously pulse-duration modulated signal to the interface to the inverter in order to operate the inverter in the second operating state.

[0012] Advantageously, the inverter can be operated asynchronously in the first operating state. Synchronous modulation methods (PWM) are usually combined with asynchronous modulation methods, which can advantageously correspond to the second operating state. The method also advantageously allows switching between asynchronous and synchronous modulation methods. Known modulation methods can be used to generate the synchronously pulse-width modulated signal.

[0013] Furthermore, a demodulator device is presented which is designed to control a method for recovering information from a space vector control in a previously mentioned variant.

[0014] Advantageously, the demodulator device can control and additionally or alternatively execute the aforementioned recovery process. The demodulator device can advantageously be designed as a chip incorporating an integrated circuit. This means that the demodulator device can advantageously be integrated into an existing system. For example, a chip representing the demodulator device can be inserted into an existing circuit layout as an additional component.

[0015] Furthermore, a control device is presented which is designed to control a method for operating an inverter in a previously mentioned variant.

[0016] Advantageously, the control device can be used to control an inverter and thus operate it in its various states, and additionally or alternatively switch between modulation methods. Advantageously, the control device can be implemented as a chip with an integrated circuit, allowing it to be designed as a plug-in component and integrated into an existing system. This saves costs, as the existing system does not need to be modified. For example, the demodulator device can be integrated as part of the control device.

[0017] Furthermore, a converter device is presented which includes a provisioning device configured to provide an input signal representing an asynchronously pulse-duration modulated signal using a space vector, an inverter, and a control device in a previously mentioned variant arranged between the provisioning device and the inverter.

[0018] The supply device can be implemented as a microcontroller. According to one embodiment, the input signal provided by the supply device can be used to operate the inverter using an asynchronous PWM method. By interposing the control device between the supply device and the inverter, the inverter can be switched between operating with both the asynchronous and synchronous PWM methods.

[0019] The converter device can be used, for example, in vehicles, but also in conjunction with other electrical machines or devices. For instance, the control device can be designed as a separate component that can be inserted into the converter device. Advantageously, operation within the converter device can be switched between two operating states.

[0020] According to one embodiment, the provisioning device can be designed as an electronic component and the control device as another electronic component. Advantageously, the two components can be separated from each other.

[0021] Furthermore, the invention relates to an electric axle drive for a motor vehicle comprising at least one electric motor, a transmission unit, and a converter device. The electric axle drive is characterized in that the converter device is designed as described.

[0022] The transmission device may include a gearbox for reducing the speed of the electric machine as well as a differential.

[0023] Furthermore, the invention relates to a motor vehicle with an electric axle drive and / or a converter device. The motor vehicle is characterized in that the electric axle drive and / or the converter device is designed as described.

[0024] The invention is explained in more detail by way of example with reference to the accompanying drawings. These show: Fig. 1 a schematic representation of a motor vehicle according to an exemplary embodiment; Fig. 2 a schematic representation of an embodiment of a converter device; Fig. 3 a schematic representation of an embodiment of a demodulator device; Fig. 4 a schematic diagram representation of a target voltage of three phases for a converter device according to an exemplary embodiment; Fig. 5 a representation of an exemplary implementation of a period of an input signal; Fig. 6 a flowchart of an embodiment of a method for recovering information from a space vector control; Fig. 7 a block diagram of an exemplary embodiment of a demodulator device; Fig. 8 a flowchart of an exemplary embodiment of a method for operating an inverter; Fig. 9 a block diagram of an exemplary embodiment of a control device; Fig. 10 a diagram representation of an exemplary embodiment of partial signals as SVPWM high-side signals; Fig. 11 a diagram representation of an exemplary embodiment of partial signals as SVPWM low-side signals; and Fig. 12 a diagram representation of an exemplary implementation of a demodulation result.

[0025] In the following description of preferred embodiments of the present invention, the same or similar reference numerals are used for the elements shown in the various figures and having a similar effect, without repeating these elements.

[0026] Fig. Figure 1 shows a schematic representation of a motor vehicle 100 according to an exemplary embodiment. The motor vehicle 100 is also referred to, for example, as a vehicle and has an electric axle drive 102, which in turn comprises at least one electric machine 104, a transmission unit 106, and a converter device 108. The electric machine 104 is also referred to, for example, as a drive unit or an electric motor and is coupled, for example, to the transmission unit 106. The motor vehicle 100 further comprises a power supply unit 110, which is referred to, for example, as a battery. According to this exemplary embodiment, the converter device 108 is connected between the power supply unit 110 and the electric machine 104.The converter device 108, for example, includes a capacitor 112 serving as an intermediate circuit capacitor and an inverter for converting a DC voltage from the power supply unit 110 into an AC voltage for operating the electric machine 104. As with known inverters, the inverter comprises a plurality of switches 114, here six in number, with three of the switches 114 being assigned to the high side and three to the low side.

[0027] For switching the switches 114, the converter device 108 has a supply device configured to provide an input signal representing an asynchronously pulse-width modulated signal using a space vector. To enable the inverter to be operated with a synchronously pulse-width modulated signal as an alternative to the asynchronously pulse-width modulated signal, the converter device 108 has a control device, which, according to one embodiment, is connected between the supply device and the inverter. Depending on the required operating mode, the control device is configured to either output the input signal for switching the switches 114 or to generate a synchronously pulse-width modulated signal using the input signal and output it for switching the switches 114.The control device is designed to determine information about a space vector of the asynchronously pulse-duration modulated signal and to use it to generate the synchronously pulse-duration modulated signal.

[0028] According to one embodiment, the converter device 108 has a plug-in PWM driver for inverter and demodulator for recovering the information of a space vector control from a pulse duration modulation signal, as described in more detail in at least one of the following figures.

[0029] Fig. Figure 2 shows a schematic representation of an embodiment of a converter device 108, which is used, for example, in Fig. 1 corresponds to or at least resembles the converter device described.

[0030] The converter device 108 includes a provisioning device 200 configured to provide an input signal 202 representing a pulse-width modulated signal asynchronously using a space vector. The provisioning device 200 is, for example, configured as an SVPWM modulator or controller. SVPWM stands for space vector-modulated pulse-width modulation.

[0031] The converter device 108 further comprises an inverter 204 and a control device 206, which is configured to control a method for recovering information from a space vector control system and / or a method for operating the inverter 204. The inverter 204 is configured to provide an alternating voltage suitable for driving an electric machine. The methods are described in more detail in at least one of the following figures. The control device 206 is arranged between the supply device 200 and the inverter 204. For example, the supply device 200 is configured as an electronic component and the control device 206 as another electronic component, such as a chip with an integrated circuit.For example, the provisioning device 200 and the control device 206 are arranged as separate components on a printed circuit board and are electrically connected to each other via conductor tracks of the printed circuit board.

[0032] The control device 206 is configured to provide a signal 202' corresponding to the input signal 202 to the inverter 204 for a first operating state, in order to control the inverter 204 using an asynchronous PWM method. For example, the control device 206 allows the input signal 202 to pass through unchanged for the first operating state of the inverter 204. Alternatively, the control device 206 is configured to use the input signal to control the inverter 204 for a second operating state using a synchronous PWM method.

[0033] The control device 206 includes a demodulator device 208 configured to control and / or execute the method for recovering information from a space vector control system. The demodulator device 208 is configured to read the input signal 202 and, according to one embodiment, to determine the duty cycle of the input signal 202. According to one embodiment, the demodulator device 208 is configured to determine a rotational speed 210 and a modulation level 212 of the space vector using the duty cycle.

[0034] The control device 206 further comprises a modulation device 214, which is configured to generate a synchronously pulse-duration modulated signal 222 using the rotation speed 210 and the modulation level 212 and to provide it to the interface to the inverter 204 in order to operate the inverter 204 in the second operating state.

[0035] According to one embodiment, both the input signal 202 for the first operating state and the synchronously pulse-width modulated signal 222 are implemented as a three-phase signal, and the inverter 204 is configured to provide three phases U, V, W of an alternating voltage for driving the electric machine. According to this embodiment, the input signal 202 comprises six sub-signals 202a, 202b, 202c, 202d, 202e, and 202f, of which each of the phases U, V, W is assigned one sub-signal as an SVPWM high-side signal and one sub-signal as an SVPWM low-side signal. According to this embodiment, the partial signal 202a is an SVPWM high-side signal and the partial signal 202d is the SVPWM low-side signal for phase U. Furthermore, the partial signal 202b represents the SVPWM high-side signal and the partial signal 202e the SVPWM low-side signal for phase V.The sub-signal 202c further represents the SVPWM high-side signal and the sub-signal 202f the SVPWM low-side signal for phase W.

[0036] In other words, the use of the control device 206 provides a way to achieve the use of an optimal pulse pattern (OPP) for pulse-width modulation (PWM) without modifying the existing hardware or the developed controller. However, generating the OPP PWM requires the modulation index and the rotational speed or position of the rotor (synchronization). To avoid using a data interface or to achieve a plug-in solution, this information is obtained by another means. This information is acquired by the described demodulator device 208.

[0037] In addition, a multitude of applications are conceivable. The demodulator device 208 presented here, also referred to as a demodulator, can be implemented as a component for the OPP driver. For example, this makes it possible, in addition to the classic control of the driver via a dedicated data interface, to insert the driver into the signal path of the inverter control signals, thus enabling switching between modulation methods during operation. Furthermore, it is possible to control BLDC motor inverters, optionally with alternative control signals, and to integrate a sensor for observer drafts and / or a sensor for analyzing the current controller output.

[0038] In other words, the control device 206 can be used, for example, as a plug-in driver or an in-circuit OPP driver. The plug-in driver is, for example, a single circuit or chip that is placed between an existing power supply unit 200 and the inverter 204. This allows the modulated signals 202, also referred to as standard asynchronous PWM, from an existing power supply unit 200 (e.g., a microcontroller) to pass through and / or, by further utilizing the PWM driver signals implemented in the power supply unit 200, to generate loss-optimized synchronous PWM signals (OPPs), here in the form of the pulse-width modulated signal 222. Apart from the insertion of the control device 206, the existing system remains unchanged, and the advantages of OPPs can be realized.

[0039] To operate an OPP driver as a plug-in solution according to one embodiment, information about the control system or the controller output is required. Specifically, the desired rotational speed 210 and the modulation level 212 are needed. To obtain this information, according to one embodiment, the control device 206 is integrated into the existing system as a component without requiring any modifications to the controller. For this purpose, the control device 206 is used with the demodulator device 208, which derives the information about the space vector in real time from the existing input signal 202, which, according to one embodiment, comprises a plurality of partial signals. For this purpose, the control device 206 is simply connected between the controller and the OPP driver.The modulator output and the inverter 204, for example in the form of an inverter, are looped in without the need to change the existing implementation and without, for example, an existing microcontroller as a provisioning device 200.

[0040] Fig. Figure 3 shows a schematic representation of an embodiment of a demodulator device 208, which is used, for example, in Fig. The demodulator device described in Figure 2 corresponds to the demodulator device 208. More precisely, the demodulator device 208 is depicted as a functional block. Here, the three-phase input signal 202 is read and processed. The demodulator device 208 determines the rotational speed 210 and thus an angle of the space vector as well as the modulation level 212. The modulation level 212 and the rotational speed 210 provide the necessary information for the control system to generate the pulse-width modulated signal.

[0041] For example, the input signal 202 includes the signals SVPWM_PHASE_U_High-Side, SVPWM_PHASE_V_High-Side, SVPWM_PHASE_W_High-Side, SVPWM_PHASE_U_Low-Side, SVPWM_PHASE_V_Low Side and SVPWM_PHASE_W_Low Side.

[0042] Fig. Figure 4 shows a schematic diagram representation of a target voltage for three phases. More precisely, the target voltage for a first phase U is shown in a first diagram 400, the target voltage for a second phase V is shown in a second diagram 402, and the target voltage for a third phase W is shown in a third diagram 404, each represented by a curve 406, 408, and 410, respectively. This means that a first curve 406 is assigned to the first phase U, a second curve 408 to the second phase V, and a third curve 410 to the third phase W. More precisely, in Fig. 4. The target voltages of the three phases U, V, W normalized to U DC(corresponding to m) is shown, where time is plotted on the abscissa and the normalized amplitude on the ordinate.

[0043] The functionality is outlined below based on the derivation: It is assumed that the space vector modulation, or the concept, is known. The normalized length of the space vector corresponds to the degree of modulation; therefore, the following applies: m=UsollUDC where U DC the DC circuit voltage corresponds to and U soll the desired amount of the space pointer.

[0044] The magnitude of the space vector corresponds to the magnitude of the instantaneous values ​​of the individual phases: |RZ→|=uu2(t)+uv2(t)+uw2(t)

[0045] Since classically the duty cycle (D) of a frequency-fixed PWM is modulated, the following applies: uu(t)=m⋅UDC⋅sin(ωt)=Du(t)⋅UDC uv(t)=m⋅UDC⋅sin(ωt+2π3)=Du(t)⋅UDC uw(t)=m⋅UDC⋅sin(ωt+4π3)=Dw(t)⋅UDC

[0046] It is already apparent that the DC link voltage has no influence on the modulation index in this context. Substituting (3), (4), (5) into (2) yields: |RZ→|=uu2(t)+uv2(t)+uw2(t)=Du2(t)+Dv2(t)+Dw2(t)=(m⋅sin(ωt))2+(m⋅sin(ωt+2π3))2+(m⋅sin(ωt+4π3))2

[0047] In a side calculation, the trigonometric expressions are to be simplified (substitution: ωt = x): sin2(x)=12(1−cos(2x))sin2(x+2π3)=(sin(x)cos(2π3)+sin(2π3)cos(x))2=(12sin(x)+32cos(x)) =14sin2(x)+32sin(x)cos(x)+34cos2(x)=14(12(1−cos(2x))+23sin(x)cos(x)+32(1+cos(2x)))=14(12−12cos(2x)+23sin(x)cos (x)+32+32cos(2x))=14(2+cos(2x)+23sin(x)cos(x))sin2(x+4π3)=(sin(x)cos(4π3)+sin(4π3)cos(x))2=(−12sin(x)−32cos(x)) =14sin2(x)−32sin(x)cos(x)+34cos2(x)=14(12(1−cos(2x))−23sin(x)cos(x)+32(1+cos(2 x)))=14(12−12cos(2x)+23sin(x)cos(x)+32+32cos(2x))=14(2+cos(2x)−23sin(x)cos(x))

[0048] Substituting (7), (8) and (9) into (6) yields: |RZ→|=m12(1−cos(2x))+14(2+cos(2x)+23sin(x)cos(x))+14(2+cos(2x)−23sin(x)cos(x))=m12 (1−cos(2x))+14(2+cos(2x)+23sin(x)cos(x))+14(2+cos(2x)−23sin(x)cos(x))=m12+12+12=m32

[0049] From (6) it is known: m32=Du2(t)+Dv2(t)+Dw2(t)m=Du2(t)+Dv2(t)+Dw2(t)32

[0050] It can be concluded from this that the magnitude of the duty cycles is proportional to the modulation level, that the duty cycles of the individual phases are proportional to their voltages, that the normalized magnitude of the space vector is directly derived from the magnitude of the duty cycles, that the DC link voltage has no influence on the space vector itself and can therefore be neglected in this consideration, and that it is irrelevant where the duty cycle is tapped, so that there is no need to intervene in the power side of the inverter.

[0051] By utilizing these relationships, the duty cycles from the three-phase system can be transformed into the stator-fixed α-β coordinate system using the Clarke transformation: [DαDβ]=32⋅[1−12−1203232]⋅[DuDvDw]

[0052] If one considers the space vector as a complex number in polar coordinates RZ→=|RZ→|eƒϕ=m32eƒϕ, Only the phase needs to be determined. Its magnitude is determined in (11). The phase φ is calculated from the Clarke transform: ϕ=tan−1(32Dv+32DvDu−12Dv−12Dw)

[0053] The space vector is now completely determined from the PWM duty cycles of the phases.

[0054] In an inverter, the high-side and low-side are driven by a corresponding control signal, for example, with the respective half-wave of the fundamental harmonic, where the high-side is driven by the positive half-wave and the low-side by the negative half-wave. By extracting these two signals and adding them together, the space vector PWM can be demodulated from the sum. For this purpose, the duty cycle of the current period is determined for each of the phases U, V, W. This is done, for example, using two counters for each phase, where one counter stops on the falling edge and the other on the rising edge. Both counter registers are reset on the rising edge. Relating the values ​​of both counter registers yields the duty cycle: D=THTPWM=THTH+TL=nH⋅1ƒcountnH⋅1ƒcount+nL⋅1ƒcount=nHnH+nL, with T H for the duration of the high level, T L for the duration of the low level, f countthe counting frequency, n H the counted bars for the high level and n L the counted bars of the low level.

[0055] Fig. 5 shows the aforementioned sizes T H , T L and T PWM a PWM period of an input signal 202 with (|x̅| = D · x̂) plotted mean value.

[0056] Fig. Figure 6 shows a flowchart of an exemplary embodiment of method 500 for recovering information from a space vector control system. Method 500 is implemented, for example, using the information derived from Fig. The demodulator device 208 described in Section 3 is implemented. Method 500 comprises a step 502 of determining a duty cycle of an input signal using the input signal, wherein the input signal represents a pulse-duration modulated signal using a space vector, and a step 504 of determining a rotational speed and a modulation level of the space vector using the duty cycle. For example, the modulation level corresponds to a normalized length of the space vector.

[0057] According to this embodiment, in step 504 of the determination process, the rotational speed is determined using a Clarke transform. For example, the input signal represents a three-phase signal, so in step 502 of the determination process, a first duty cycle of the first phase of the input signal, a second duty cycle of the second phase of the input signal, and a third duty cycle of the third phase of the input signal are determined. Consequently, in step 504 of the determination process, the rotational speed and the modulation level of the space vector are determined using the first, second, and third duty cycles.

[0058] Fig. Figure 7 shows a block diagram of an embodiment of a demodulator device 208, as used, for example, in at least one of the Fig. 1 to 3 described or at least mentioned. The demodulator device 208 is configured to control and / or execute a process such as that described, for example, in Fig. 5 was described. For this purpose, the demodulator device 208 has a determination unit 600 and a detection unit 602.

[0059] The determination unit 600 is configured to determine a duty cycle 604 of an input signal 202 using the input signal 202, wherein the input signal 202 represents a pulse-duration modulated signal using a space vector.

[0060] The determination unit 602 is configured to determine a rotational speed 210 and a modulation level 212 of the space vector using the duty cycle 604. According to this embodiment, the input signal 202 represents a three-phase signal, so the determination unit 600 is configured to determine the first duty cycle 604 of a first phase of the input signal 202, a second duty cycle 606 of a second phase of the input signal 202, and a third duty cycle 608 of a third phase of the input signal 202.

[0061] Consequently, the determination unit 602 is designed to determine the rotational speed 210 and the modulation degree 212 of the space pointer using the first duty cycle 604, the second duty cycle 606 and the third duty cycle 608.

[0062] Fig. Figure 8 shows a flowchart of an embodiment of a method 700 for operating an inverter, as used in at least one of the Fig. 1 to 2 described or at least mentioned. For example, procedure 700 is carried out and / or controlled in a control device such as that described in Fig. 2 was described. Method 700 allows the inverter to be operated switchably in a first operating state or in a second operating state. Method 700 comprises a reading step 702, a determining step 704, an output step 706, a creation step 708, and a further output step 710.

[0063] In step 702 of the reading process, an input signal 202 is read in, representing a signal asynchronously pulse-duration modulated using a space vector. In step 704 of the determination process, a rotational speed and a modulation level of the space vector of the input signal are determined using a method as described in Fig. As described in section 5. In step 706 of the output process, the input signal is output to an interface to the inverter to operate the inverter in the first operating state. In step 708 of the creation process, a synchronously pulse-width modulated signal is created using the rotational speed and the modulation level, and in the subsequent step 710 of the output process, the synchronously pulse-width modulated signal is output to the interface to the inverter to operate the inverter in the second operating state.

[0064] Optionally, step 704 and thus steps 708 and 710 for the first operating state can be omitted, since in this case the input signal can be used directly to control the inverter.

[0065] Fig. Figure 9 shows a block diagram of an exemplary embodiment of a control device 206, which is used, for example, in Fig. The control device described in section 2 is similar to or corresponds to the control device described in section 2. The control device 206 is configured to control and / or execute a method for operating an inverter in a first operating state and in a second operating state, as is described, for example, in section 2. Fig. 8 was described.

[0066] The control device 206 includes a demodulator device 208 and a modulation device 214.

[0067] By way of example, the demodulator device 208 comprises a reading unit 800, a detection unit 802, and an output unit 804. The reading unit 800 is configured to read an input signal 202, which represents a signal asynchronously pulse-duration modulated using a space vector. The detection unit 802 is configured to determine a rotational speed 210 and a modulation level 212 of the space vector of the input signal 202, for example, using a method as described in Fig. The output unit 804 is designed to output the rotational speed 210 and the modulation level 212, for example in the form of signals to the modulation device 214, as described in section 7.

[0068] The modulation device 214 comprises, by way of example, a generation unit 806 and a further output unit 808. The generation unit 806 is configured to generate a synchronously pulse-width modulated signal 222 using the rotational speed 210 and the modulation level 212. The further output unit 808 is configured to output the synchronously pulse-width modulated signal 222 to an interface with the inverter 204 in order to operate the inverter in the second operating state.

[0069] According to one embodiment, the control device 206 comprises a forwarding unit 810 configured to output the input signal 202 as input signal 202' to the interface to the inverter 204 in order to operate the inverter 204 in the first operating state. In other words, the input signal 202 is passed through for the first operating state.

[0070] This allows switching between multiple modulation methods.

[0071] The individual units 800, 802, 804, 806, 808, 810 are, for example, the in Fig. 2 described demodulator device 208 and modulation device 214, or may be designed as part of the same.

[0072] Fig. Figure 10 shows a diagram representation of an embodiment of partial signals 202a, 202b, 202c as SVPWM high-side signals, as already described, for example, in at least one of the Fig. 2 to 3 were described. According to this embodiment, the curve represents control signals over a period of time. The individual peaks of the partial signals 202a, 202b, 202c of the phases occur at different times.

[0073] Fig. Figure 11 shows a diagram representation of an embodiment of partial signals 202d, 202e, 202f as SVPWM low-side signals, as already described, for example, in at least one of the Fig. 2 to 3 were described. According to this embodiment, the curve represents control signals over a period of time. The individual peaks of the sub-signals 202d, 202e, 202f of the phases occur at different times. If one compares, for example, the peaks in the Fig. 10 and Fig. 11, it is found that both the peaks of the high-side signals and the peaks of the low-side signals occur at different times.

[0074] Fig. Figure 12 shows a diagram representation of an exemplary embodiment of a demodulation result of a method for recovering information from a space vector control system, as is the case, for example, in Fig.6 was described. To represent the rotational speed 210, time is plotted on the abscissa and the angle phi [radians] on the ordinate, and to represent the modulation degree 212 of the space vector, time is plotted on the abscissa and the modulation depth on the ordinate.

[0075] According to this embodiment, the modulation level 212 initially increases linearly until a certain value is reached and then remains constant. The rotational speed 210 has a uniform period. Reference sign 100 motor vehicles 102 Electric axle drive 104 Electric Machine 106 Gearbox unit 108 Converter device 110 Energy supply facility 112 Capacitor 114 Plural of switches 200 provisioning facility 202 Input signal 202a Partial signal of the input signal 202b Partial signal of the input signal 202c Partial signal of the input signal 202d Partial signal of the input signal 202e Partial signal of the input signal 202f Partial signal of the input signal 202' Input signal 204 inverters 206 Control device 208 Demodulator device 210 rotational speed 212 Modulation level 214 Modulation unit 222 synchronous pulse-width modulated signal 400; U first phase 402; V second phase 404; W third phase 406 first curve 408 second curve 410 third curve 500 methods for recovering information from a space vector control Step 502 of determining Step 504 of determining 600 units of determination 602 Investigation Unit 604 first duty cycle 606 second duty cycle 608 third duty cycle 700 methods for operating an inverter in a first operating state and in a second operating state Step 702 of the reading process Step 704 of the determination process Step 706 of spending Step 708 of the creation process 710 further step of spending 800 reading units 802 Investigation Unit 804 output unit 806 creation unit 808 additional output units

Claims

[1] Method (500) for recovering information from a space vector controller, wherein the method (500) comprises the following steps: Determining (502) a duty cycle (604) of an input signal (202) using the input signal (202), wherein the input signal (202) represents a pulse-duration modulated signal using a space vector; and Determine (504) a rotational speed (210) and a modulation degree (212) of the space vector using the duty cycle (604). [2] Method (500) according to claim 1, wherein in step (504) of determining the rotational speed (210) is determined using a Clarke transformation. [3] Method (500) according to one of the preceding claims, wherein the input signal (202) represents a three-phase signal, and in the step (502) of determining a first duty cycle (604) of a first phase (U) of the input signal (202), a second duty cycle (606) of a second phase (V) of the input signal (202) and a third duty cycle (608) of a third phase (W) of the input signal (202) is determined, wherein in the step (504) of determining the rotational speed (210) and the modulation level (212) of the space vector is determined using the first duty cycle (604), the second duty cycle (606) and the third duty cycle (608). [4] Method (700) for operating an inverter (204) in a first operating state and in a second operating state, wherein the method (700) comprises the following steps: Reading (702) an input signal (202) representing a pulse-duration modulated signal asynchronously using a space pointer; Determining (704) a rotational speed (210) and a modulation level (212) of the space vector of the input signal (202) using a method (500) according to one of the preceding claims; Output (706) of the input signal (202') to an interface to the inverter (204) in order to operate the inverter (204) in the first operating state; Creating (708) a synchronously pulse-duration modulated signal (222) using the rotation speed (210) and the modulation level (212); and Output (710) of the synchronously pulse-duration modulated signal (222) to the interface to the inverter (204) in order to operate the inverter (204) in the second operating state. [5] Demodulator device (208) configured to control a method (500) according to any one of claims 1 to 3. [6] Control device (206) configured to control a method (700) according to claim 4. [7] Converter device (108) with the following features: a provisioning device (200) configured to provide an input signal (202) representing a pulse-duration modulated signal asynchronously using a space pointer; an inverter (204); and a control device (206) according to claim 6, which is connected between the provisioning device (200) and the inverter (204). [8] Converter device (108) according to claim 7, wherein the provision device (200) is designed as an electronic component and the control device (206) is designed as a further electronic component. [9] Electric axle drive (102) for a motor vehicle (100) comprising at least one electric machine (104), a transmission device (106) and a converter device according to one of claims 7 to 8. [10] Motor vehicle (100) comprising an electric axle drive (102) according to claim 9 and / or a converter device according to one of claims 7 to 8.

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