DE102020205981A1 - Assembly of a vehicle with an integrated actuator - Google Patents

Abstract

An assembly of a vehicle comprises an integrated actuator (2) for adjusting a vehicle assembly (11), which has an electromotive adjustment drive (21) for adjusting the vehicle assembly (11), a power control assembly (220) with an arrangement of semiconductor switching units (HS1, HS2 , LS1, LS2) for electrically feeding the adjustment drive (21), a logic module (222) for controlling the adjustment drive (21) for performing an adjustment process and a communication module (223) for exchanging data with a higher-level control unit (3). The power control module (220) has a control module (224) for switching the semiconductor switching units (HS1, HS2, LS1, LS2) between an on state and an off state. A first of the semiconductor switching units (HS1, HS2, LS1, LS2) and a second of the semiconductor switching units (HS1, HS2, LS1, LS2) form a current path for electrically feeding the adjustment drive (21) in the on state. It is provided that the control module (224) is designed to feed the adjustment drive (21) in a pulse-width-modulated manner, the first of the semiconductor switching units (HS1, HS2, LS1, LS2) and the second of the semiconductor switching units (HS1, HS2, LS1, LS2) to switch between the on-state and the off-state according to a predetermined switching scheme in order to interrupt the current path for the pulse-width-modulated feeding of the adjustment drive (21).

Description

The invention relates to an assembly of a vehicle according to the preamble of claim 1 and to a method for adjusting a vehicle assembly.

Such an assembly comprises an integrated actuator for adjusting a vehicle assembly. The integrated actuator comprises an electromotive adjustment drive for adjusting the vehicle assembly, a power adjustment assembly with an arrangement of semiconductor switching units for electrically feeding the adjustment drive, a logic module for controlling the adjustment drive for performing an adjustment process and a communication module for exchanging data with a higher-level control unit. The power control module has a control module for switching the semiconductor switching units between an on state and an off state. A first of the semiconductor switching units and a second of the semiconductor switching units form, in the on state, a current path for electrically feeding the adjustment drive.

Such a vehicle assembly can, for example, be a door or flap on a motor vehicle. A door can be formed, for example, by a vehicle side door arranged pivotably on a vehicle body or by a tailgate or a sliding door. The vehicle assembly can, for example, also be a sliding roof or another adjustment unit, for example on a vehicle seat or on a ventilation device.

In the present case, an integrated actuator is understood to mean a drive device that is integrated in such a way that it can perform an adjustment function for adjusting a vehicle assembly, for example a tailgate or an assembly of a vehicle seat, largely independently, i.e. largely without a higher-level controller. Modules of the integrated actuator are integrated in a common housing, so that the integrated actuator can be arranged at the location of the vehicle assembly to effect the adjustment movement of the vehicle assembly.

Such an integrated actuator can promote a modular design in a vehicle, for example in that in a vehicle only commands for triggering an adjustment process, for example for opening or closing a tailgate, are transmitted to an assigned actuator from a central controller, which then largely carries out an adjustment process executes automatically.

Such an integrated actuator should require little installation space, so that the integrated actuator can be installed on a vehicle assembly that is to be adjusted. This requires modules of the actuator, such as the adjustment drive, the power control module, the logic module and the communication module to be arranged in a tight installation space, but this can have the disadvantage that thermal power loss, for example at the semiconductor switching units of the power control module, can be dissipated more poorly can be.

Heat is generated in semiconductor switching units, among other things, by switching processes that are carried out when the adjustment drive is energized as part of a pulse width modulation. Usually, within the scope of the power control module, semiconductor switching units are interconnected to form a switching bridge, in that the semiconductor switching units jointly form a full bridge for energizing the adjustment drive. When the adjustment drive is driven in one direction of rotation, a current flows along a current path, for example via a first semiconductor switching unit, which is connected, for example, to a supply voltage and is also referred to as a high-side switching unit, and a second semiconductor switching unit, which is for example connected to a ground potential is connected and is referred to as a low-side switching unit. As part of the pulse width modulation, one of the switching units, usually the high-side switching unit, is switched between an on-state and an off-state using a duty cycle, so that the current path is interrupted in a clocked manner and the motor current is interrupted using a The mean value of the pulsed current flow is set. In this case, due to the switching operations on the high-side switching unit, heat losses occur which can lead to heating, in particular of the high-side switching unit.

From the DE 10 2007 031 548 A1 an electric motor commutator with a switching bridge with a high-side semiconductor and a low-side semiconductor is known. The commutator has a pulse width modulator for controlling the switching bridge. The pulse width modulator is connected to both semiconductors. The pulse width modulator is switched through alternately to the two semiconductors, creating a uniform Heating of all semiconductors of the switching bridge can be realized so that the power loss and the temperature load of the semiconductors are the same.

The object of the present invention is to provide a subassembly of a vehicle with an integrated actuator and a method for adjusting a vehicle subassembly, which enable a thermally favorable operation and thus an integration of modules of the actuator into one another.

This object is achieved by an object with the features of claim 1.

Accordingly, the control module is designed to switch the first of the semiconductor switching units and the second of the semiconductor switching units between the on-state and the off-state in accordance with a predetermined switching pattern for pulse-width-modulated feeding of the adjustment drive, in order to switch the current path for pulse-width-modulated feeding of the adjustment drive to interrupt.

While usually when controlling an adjustment drive in the form of an electric motor for adjusting a vehicle assembly, for example a tailgate or a seat assembly, a (single) semiconductor switching unit is switched in a current path of a switching bridge and another semiconductor switching unit is continuously switched through to create a current flow To enable the current path in a pulsed manner, it is provided in the present case that the control module switches the first semiconductor switching unit and the second semiconductor switching unit in the current path alternately according to a predetermined switching scheme. The switching scheme can provide for a regular or irregular change between switching the first semiconductor switching unit and the second semiconductor switching unit within the scope of the pulse width modulation. In any case, switching operations are carried out to provide the pulse width modulation and thus to interrupt the current path in a pulsed manner on the first semiconductor switching unit and the second semiconductor switching unit.

In this way, it is made possible that the semiconductor switching units of the power control assembly do not predominantly heat up on a single semiconductor switching unit, but rather that heat losses are preferably evenly distributed over a plurality of semiconductor switching units. This can prevent a semiconductor switching unit from heating up excessively, in that heat losses are distributed over a plurality of semiconductor switching units.

The switching scheme can be predetermined in such a way that regular alternation between switching the first semiconductor switching unit and the second semiconductor switching unit is provided, so that heating occurs at least approximately uniformly on the semiconductor switching units in the current path.

However, the circuit diagram can also be such that the semiconductor switching units of the current path heat up irregularly, for example by performing more switching operations on one of the semiconductor switching units. Such a procedure can be beneficial, for example, if one of the semiconductor switching units enables improved heat dissipation, for example if a semiconductor switching unit is in such a position in the actuator that it is advantageously connected to a heat sink for heat dissipation, for example can be, but not another semiconductor switching unit. In this case, for example, more switching operations can be carried out on the semiconductor switching unit that is thermally more favorably connected for heat dissipation than on the other semiconductor switching unit in the current path.

The switching scheme specifies the change between a switching phase in which the first of the semiconductor switching units is switched and a switching phase in which the second of the semiconductor switching units is switched. The switching scheme can be matched to a frequency of the pulse width modulation, within which the adjustment drive is pulsed with a duty cycle that indicates the duration of a pulse in relation to the period determined by the modulation frequency and is also referred to as the duty cycle.

The integrated actuator has, for example, a sensor assembly for detecting an adjustment movement on the adjustment drive. The integrated actuator should have an integrated control for the operation of the adjustment drive and for this purpose it has components and modules that enable largely independent operation for carrying out an adjustment process. For example, the integrated actuator can only receive an adjustment command from a higher-level control unit (which is implemented, for example, by a central control of a vehicle) via the communication module, which prompts the integrated actuator to perform an adjustment process to adjust the vehicle assembly, for example a tailgate or an assembly of a vehicle seat. The actual adjustment process is then controlled by the integrated actuator itself, in particular by the logic module of the integrated actuator in cooperation with the power control module. The logic module can in particular be designed to evaluate sensor signals from the sensor assembly in order to control the adjustment process as a function of the sensor signals.

The sensor assembly can have Hall sensors, for example, with which a rotary movement of a motor shaft of the adjustment drive can be detected. Using sensor signals from the sensor assembly, a speed of the adjustment drive and an adjustment path can be determined using, for example, counting pulses from the Hall sensors.

The logic module can in particular be designed to evaluate sensor signals of the sensor assembly or other sensors that are part of the integrated actuator or also external to the integrated actuator to provide a safety functionality in order to control an adjustment process as a function of such an evaluation. For example, the logic module can provide anti-trap functionality, overvoltage protection functionality and / or overtemperature protection functionality. As part of an anti-jamming functionality, it can be recognized, for example, whether an object is in the adjustment path of a vehicle assembly to be adjusted, for example by evaluating the speed of the adjustment drive or the motor current, so that an adjustment process can be modified or interrupted if a jamming event is detected. As part of an overvoltage protection functionality, a malfunction in the event of an overvoltage can be prevented. As part of an overtemperature protection functionality, excessive heating can be counteracted, for example by modifying or stopping an adjustment process.

As part of the integrated actuator, the components and modules of the actuator, in particular the adjustment drive, the power control assembly and the logic module, are integrated in a common housing and can thus be arranged in an integrated manner at the location of the vehicle assembly in order to carry out an adjustment process on the vehicle assembly.

In one embodiment, the semiconductor switching units are formed by transistors, in particular MOSFETs (metal-oxide-semiconductor field effect transistors), to which diodes can optionally be connected in parallel or which can have intrinsic diodes, so-called body diodes. The semiconductor switching units are connected to the control module, in particular in that the control module is connected to a gate of each transistor formed, for example, by a MOSFET for providing a control voltage for switching the respective semiconductor switching unit.

The first semiconductor switching unit can, for example, form a so-called high-side switching unit connected to a supply voltage, while the second of the semiconductor switching units represents a low-side switching unit connected to a ground potential. If both semiconductor switching units are in their on state, the adjustment drive, which is arranged between the semiconductor switching units, is connected to the supply potential via the first semiconductor switching unit and to ground potential via the second semiconductor switching unit, so that a motor current flows into the Adjustment drive is fed. By alternately switching the semiconductor switching units, the current path formed in this way can be interrupted so that pulse width modulation of the motor current is carried out.

The semiconductor switching units of the arrangement of the power control assembly preferably together form a full bridge for feeding the adjustment drive. While one with two semiconductor switching units enables the adjustment drive to be operated, for example, in a (certain) direction of rotation, a full bridge - which is formed by two high-side switching units and two low-side switching units that are interconnected to form an H-bridge - can be used Enable operation of the adjustment drive in different directions of rotation by energizing the adjustment drive in different directions.

In one embodiment, the control module is designed to switch the first of the semiconductor switching units and the second of the semiconductor switching units between the on state and the off state in such a way that a predetermined first number of switching operations of the first the semiconductor switching units is followed by a predetermined second number of switching operations of the second of the semiconductor switching units. In a first phase, the first semiconductor switching unit is thus switched between the on-state and the off-state for the predetermined first number of switching operations. In this first phase, the second semiconductor switching unit is switched through and is therefore in its on state. In a second phase that follows, the second Semiconductor switching unit switched for the predetermined second number of switching operations between the on-state and the off-state, while the first semiconductor switching unit is continuously in the on-state. There is thus a pulsed energization of the adjustment drive in the sense of a pulse width modulation.

The first number of switching operations and the second number of switching operations is each equal to or greater than 1. The first predetermined number and the second predetermined number can be the same, for example. For example, if the first number and the second number are equal to 1, the first semiconductor switching unit and the second semiconductor switching unit are switched alternately, so that a switching operation of the first semiconductor switching unit is followed by a switching operation on the second semiconductor switching unit and thus between different phases for alternating switching of the switching units is changed according to the modulation frequency of the pulse width modulation.

However, it is also conceivable that the first number and the second number are greater, for example significantly greater than 1, for example 5, 10, 20, 100 or 200.

In one embodiment, the control module is designed to switch the first of the semiconductor switching units and the second of the semiconductor switching units in a first control phase with a first duty cycle and in a second control phase with a second duty cycle different from the first duty cycle for pulse-width modulated feeding of the adjustment drive . The first control phase can, for example, correspond to a start-up process when the vehicle assembly is adjusted. In contrast, the second activation phase can correspond to an adjustment of the vehicle assembly after it has started up. Correspondingly, the first duty cycle can be greater than the second duty cycle. For example, the first duty cycle can be in a range between 50% and 100%, while the second duty cycle is in a range between 0% and 50%. In each case, the duty cycle corresponds to the ratio of the length of a current pulse and the period duration within the scope of the pulse width modulation.

The first control phase can be significantly shorter than the second control phase. In the first control phase, greater thermal losses and thus greater heating of the semiconductor switching units occur with a greater duty cycle, so that it may be desirable to keep the first control phase short compared to the second control phase.

The length of the control phases and a change between the control phases can be set dynamically during operation by monitoring power loss or energy loss on the semiconductor switching units of the power control module during operation. The power loss and the energy loss, which leads to heating of the semiconductor switching units, can for example be calculated during operation using the motor current and the number of switching processes using a model calculation. If, for example, during the first control phase it is determined on the basis of such a monitoring that the heating on one or more of the semiconductor switching units exceeds a predetermined threshold value, then it is possible to switch to the second control phase with a reduced duty cycle in order to counteract excessive heating.

In one embodiment, the control module is designed to switch the first of the semiconductor switching units and the second of the semiconductor switching units with a predetermined duty cycle for pulse-width-modulated feeding of the adjustment drive if a target duty cycle required to carry out an adjustment is in an energetically unfavorable range between a predetermined lower one Duty cycle limit and a predetermined upper duty cycle limit is. The predetermined duty cycle is set here, for example, to the upper duty cycle limit or the lower duty cycle limit or a value outside the range specified by the duty cycle limits if the target duty cycle is in the range. The idea behind this is that in a range, for example with a duty cycle between 85% and 99.9%, it is energetically more favorable to set a duty cycle of 100% because switching losses increase in a duty cycle range between 85% and 99.9% increased switching losses and thus would lead to greater heating than with a duty cycle of 100%. If a duty cycle within the predetermined, unfavorable duty cycle range is required for an adjustment process, for example for starting from a certain adjustment position, a different duty cycle value is set instead of the target duty cycle, which is at the limits of the range or outside the range, so that a thermally unfavorable one Duty cycle range is avoided.

It would also be conceivable to alternate between two duty cycle values, for example between 85% and 100%, in order to set intermediate values.

The duty cycle limits can be defined in advance. These duty cycle limits can be determined, for example, using a model calculation in which the switching losses are included.

The object is also achieved by a method for performing an adjustment process for a vehicle assembly. In the method, the vehicle assembly is adjusted by an integrated actuator which has an electric motor adjustment drive, a power adjustment assembly with an arrangement of semiconductor switching units for electrically feeding the adjustment drive, a logic module for controlling the adjustment drive to carry out the adjustment process and a communication module for exchanging data having a higher-level control unit. The control module of the power control module switches the semiconductor switching units between an on state and an off state. A first of the semiconductor switching units and a second of the semiconductor switching units form, in the on state, a current path for electrically feeding the adjustment drive. It is provided that the control module for pulse-width-modulated feeding of the adjustment drive switches the first of the semiconductor switching units and the second of the semiconductor switching units according to a predetermined switching pattern between the on-state and the off-state, in order to establish the current path for pulse-width-modulated feeding of the adjustment drive to interrupt.

The advantages and advantageous configurations described above for the assembly are also applied analogously to the method, so that reference should be made to what has been stated above.

• 1 eine schematische Ansicht einer Fahrzeugbaugruppe in Form einer Heckklappe eines Fahrzeugs;
• 2 eine schematische Ansicht der Fahrzeugbaugruppe in Form der Heckklappe, mit daran angeordneten integrierten Aktoren;
• 3 eine schematische Ansicht eines integrierten Aktors;
• 4 eine schematische Ansicht einer Leistungsstellbaugruppe eines integrierten Aktors;
• 5 eine Ansicht der Leistungsstellbaugruppe in einem ersten Schaltzustand während einer Pulsweitenmodulation zum Speisen eines Verstellantriebs;
• 6 eine Ansicht der Leistungsstellbaugruppe in einem anderen Schaltzustand;
• 7A eine schematische Ansicht eines Ansteuersignals zum Schalten von Halbleiter-Schalteinheiten und eines sich ergebenden Stromflusses eines Motorstroms, nach einem herkömmlichen Schema;
• 7B eine schematische Ansicht eines Ansteuersignals zum Schalten von Halbleiter-Schalteinheiten und eines sich ergebenden Stromflusses eines Motorstroms, nach einem vorgeschlagenen Schema;
• 8A eine Ansicht einer Verlustleistung an den Halbleiter-Schalteinheiten einer Leistungsstellbaugruppe; und
• 8B eine Ansicht der sich ergebenden Verlustenergie an den Halbleiter-Schalteinheiten.

The idea on which the invention is based will be explained in more detail below with reference to the exemplary embodiments shown in the figures. Show it:

• 1 a schematic view of a vehicle assembly in the form of a tailgate of a vehicle;
• 2 a schematic view of the vehicle assembly in the form of the tailgate, with integrated actuators arranged thereon;
• 3 a schematic view of an integrated actuator;
• 4th a schematic view of a power control module of an integrated actuator;
• 5 a view of the power control module in a first switching state during a pulse width modulation for feeding an adjustment drive;
• 6th a view of the power control module in a different switching state;
• 7A a schematic view of a control signal for switching semiconductor switching units and a resulting current flow of a motor current, according to a conventional scheme;
• 7B a schematic view of a control signal for switching semiconductor switching units and a resulting current flow of a motor current, according to a proposed scheme;
• 8A a view of a power loss on the semiconductor switching units of a power control module; and
• 8B a view of the resulting energy loss at the semiconductor switching units.

1 shows a vehicle assembly in a schematic view 11th in the form of one on a vehicle body 10 of a motor vehicle 1 arranged tailgate around a hinge axis 110 to the vehicle body 10 is pivotable and between a closed position x1 and an open position x2 along an opening direction O can be pivoted.

A drive device in the form of an integrated actuator 2 is used to adjust the vehicle assembly by means of an electric motor 11th and is designed in the manner of an adjusting strut that extends between the vehicle body 10 and the vehicle assembly 11th extends in the form of the tailgate. Integrated actuators 2 can for example be on both sides of the vehicle assembly 11th be arranged in the form of the tailgate to ensure a symmetrical introduction of force into the vehicle assembly 11th as this is shown schematically in 2 is shown. The integrated actuators 2 each have two strut sections 200 , 201 on that using an electromotive adjustment drive 21 are longitudinally displaceable relative to one another, by between the vehicle body 10 and the vehicle assembly 11th effective length of the integrated actuators 2 to change and the vehicle assembly 11th thus relative to the vehicle body 10 to adjust.

Adjusting the vehicle assembly 11th can in an automatic, electrical adjustment mode between defined positions x1 , x2 take place, one position x1 for example the closed one Position of the vehicle assembly 11th and another position x2 for example a maximally open position of the vehicle assembly 11th can correspond. An opening of the vehicle assembly 11th takes place along the opening direction O around the hinge axis 110 to which the vehicle door 11th articulated to the vehicle body 10 is adjustable.

The integrated actuators 2 should, for example, enable automatic operation and thus automatic, electrical adjustment of the vehicle assembly 11th can cause. In automatic mode, for example, regulation can be carried out using a speed to control the vehicle assembly 11th to move between different positions, for example the closed position and an open position.

The integrated actuators 2 should enable an essentially self-sufficient adjustment operation. As schematically in 3 is shown, have the integrated actuators 2 in the illustrated embodiment each have an adjusting drive 21 as well as control electronics 22nd on which a power control module 220 , a sensor assembly 221 , a logic module 222 and a communication module 223 having. The power control module 220 serves to feed a motor current into the adjustment drive 21 to adjust the actuator 21 to adjust the assigned vehicle assembly (in the example according to 1 and 2 the tailgate 11th ) head for. The sensor assembly 221 is used, for example, to detect an adjustment movement on the adjustment drive 21 and includes, for example, Hall sensors that detect a rotary movement of a motor shaft of the adjustment drive 21 detect and enable detection of the speed and the adjustment position. The logic module 222 is to control the adjustment drive 21 and can, for example, have an electronic module in the form of a microprocessor or Asics, which controls an adjustment process and, for example, also provides protection functionality such as anti-trap protection, overvoltage protection and overtemperature protection. The communication module 223 can for example be designed as a bus module and provides a communication link with a bus system 4th of the vehicle 1 , for example in the form of a LIN bus or CAN bus. The modules are together in one housing 23 of the integrated actuator 2 enclosed and are thus integrated with one another in order to provide a compact drive unit at the location of the vehicle assembly to be adjusted.

As schematically in 2 shown, any integrated actuator 2 via the bus system 4th with a higher-level control unit 3 in the form of a central control of the vehicle 1 be connected. The central control 3 can send control commands to the integrated actuators 2 transmit, for example a control command to open or close the vehicle assembly to be adjusted, for example the tailgate 11th . Adjustment mode is then carried out by the integrated actuators after receiving the control command 2 independently undertaken and controlled, so that in particular a control of the adjustment drives 21 including any protective functionality to be provided, such as anti-trap protection, automatically by the actuators 2 he follows.

4th shows an embodiment of a power control module 220 the control electronics 22nd . In the illustrated embodiment, the power control module 220 by an arrangement of semiconductor switching units HS1 , HS2 , LS1 , LS2 formed, which together realize a switching bridge in the manner of a full bridge (H-bridge). Each semiconductor switching unit HS1 , HS2 , LS1 , LS2 has a transistor T1-T4 in the form of a MOSFET, which is an intrinsic so-called body diode D1-D4 having. Two of the semiconductor switching units HS1 , HS2 are connected to a supply voltage U _B and thus implement high-side switching units. The other semiconductor switching units LS1 , LS2 are on the other hand at a ground potential M. connected and implement lowside switching units.

Another semiconductor switching unit RPP serves as polarity reversal protection and is implemented by a transistor T5 in the form of a MOSFET with a body diode D5 educated.

The semiconductor switching units HS1 , HS2 , LS1 , LS2 , RPP are shared via a control module 224 controlled, each with the gate of the transistors T1-T5 of the semiconductor switching units HS1 , HS2 , LS1 , LS2 , RPP is connected and the switching units HS1 , HS2 , LS1 , LS2 , RPP controls via a control voltage. The logic module 220 controls the control module via a microcontroller 224 for switching the semiconductor switching units HS1 , HS2 , LS1 , LS2 , RPP.

By means of the power control module 220 a motor current is used to carry out an adjustment process in the adjustment drive 21 fed in, the motor current via pulse width modulation by switching the semiconductor switching units HS1 , HS2 , LS1 , LS2 the switching bridge is set.

When operating the adjustment drive 21 in one direction of rotation, for example, form the semiconductor switching unit HS1 and the semiconductor switching unit LS2 together a current path S1 from, via which a motor current is fed into the adjustment drive 21 fed out like this 4th can be seen. The semiconductor switching units HS1 , LS2 are each switched to an on state to feed the motor current, so that the motor current is between the supply voltage U _B and the ground potential M. through the adjustment drive 21 can flow.

This is in 5 illustrated in the by the semiconductor switching units HS1 , LS2 formed bridge path for operating the adjustment drive 21 is shown in the assigned direction of rotation (the other semiconductor switching units HS2 , LS1 are located accordingly when energizing 5 in the off state and thus lock). The motor current is fed in in a pulsed manner in that the semiconductor switching units HS1 , LS2 alternately, as will be explained below, are switched from the on state to an off state, so that the current path is closed and opened in a pulsed manner and a motor current is established based on an average value of the current pulses set via the pulse width modulation.

As part of the pulse width modulation, the current path is in accordance with 5 thus closed and opened in a pulsed manner. For example, it is the semiconductor switching unit HS1 closed and opened in a pulsed manner, the power control module changes 220 between the state according to 5 and according to the state 6th . Are both semiconductor switching units HS1 , LS2 when on, a current flows through the in 5 current path shown. Is the semiconductor switching unit HS1 open, the power control module is located 220 in a freewheel, with a current flow via the semiconductor switching unit, which is still in the on state LS2 and also the diode D3 the semiconductor switching unit LS1 according to the in 6th current path shown. Becomes the semiconductor switching unit HS1 opened, the diode switches D3 the semiconductor switching unit LS1 in freewheel due to an adjustment drive 21 continued current flow and a voltage induced thereby, the semiconductor switching unit usually after a short dead time LS1 is switched through (so-called active freewheeling), because the losses on the through-connected MOSFET during freewheeling are lower than on the associated body diode.

The pulse width modulation for operating an adjustment drive for adjusting a vehicle assembly takes place conventionally, as shown in FIG 7A is shown, in that a control signal to the semiconductor switching unit HS1 is created in the form of the high-side switching unit, so that the semiconductor switching unit HS1 switches on and off in a pulsed manner (see the upper signal in 7A) . The switching unit LS2 in the form of the low-side switching unit, on the other hand, is switched on permanently (see the middle signal in 7A) . The result is a current flow corresponding to that in 7A The curve shown below, in which the motor current changes in a pulsed manner based on the duty cycle of the semiconductor switching unit HS1 adjusts.

The in 7A Strictly speaking, the pulsed current shown below corresponds to the current flow taken from the energy source. Due to the freewheeling, the motor current will continue to exist in the freewheeling phase. The result is an average motor current with a slight increase during the active phase and a slight decrease during the freewheeling phase.

When switching the semiconductor switching units HS1 , HS2 , LS1 , LS2 In the context of the pulse width modulation, there is a power loss in the semiconductor switching units HS1 , HS2 , LS1 , LS2 . Due to the power loss in the semiconductor switching units HS1 , HS2 , LS1 , LS2 , RPP, the semiconductor switching units heat up HS1 , HS2 , LS1 , LS2 , RPP, which occurs with asymmetrical switching of the semiconductor switching units HS1 , HS2 , LS1 , LS2 , as in 7A shown, to an unequal heating of the different semiconductor switching units HS1 , HS2 , LS1 , LS2 , RPP leads.

For the in 5 and 6th The switching states shown here can be used to determine the power loss at the various semiconductor switching units HS1 , HS2 , LS1 , LS2 , Calculate RPP. The power loss at the semiconductor switching unit RPP serving as polarity reversal protection results as follows: $$\mathrm{P.}={\mathrm{I.}}_{\mathrm{L.}}{}^2\cdot {\mathrm{R.}}_{\mathrm{D.}\mathrm{S.},On}\cdot \mathrm{D.}uty$$

$$P=\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\cdot U_B\cdot I_L\cdot t_{ein}\cdot {ƒ}_{PWM}+I^2\cdot R_{DS,on}\cdot Duty+\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\cdot U_B\cdot I_L\cdot t_{aus}\cdot {ƒ}_{PWM}$$

The power loss on the semiconductor switching unit HS1 in the on phase can be calculated as follows: $$\mathrm{P.}={\mathrm{P.}}_{ein}+{\mathrm{P.}}_{stat,akt}+{\mathrm{P.}}_{aus}$$

$$\mathrm{P.}=\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\cdot U_{\mathrm{B.}}\cdot {\mathrm{I.}}_{\mathrm{L.}}\cdot t_{ein}\cdot {ƒ}_{\mathrm{P.}\mathrm{W.}\mathrm{M.}}+{\mathrm{I.}}^2\cdot {\mathrm{R.}}_{\mathrm{D.}\mathrm{S.},On}\cdot \mathrm{D.}uty+\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\cdot U_{\mathrm{B.}}\cdot {\mathrm{I.}}_{\mathrm{L.}}\cdot t_{aus}\cdot {ƒ}_{\mathrm{P.}\mathrm{W.}\mathrm{M.}}$$

The power loss on the semiconductor switching unit LS2 can be calculated as follows: $$\mathrm{P.}={\mathrm{I.}}_{\mathrm{L.}}{}^2\cdot {\mathrm{R.}}_{\mathrm{D.}\mathrm{S.},On}$$

$$P=U_{Body}\cdot I_L\cdot t_{tot1}\cdot {ƒ}_{PWM}+I^2\cdot R_{DS,on}\cdot \left(1-Duty\right)+U_{Body}\cdot I_L\cdot t_{tot2}\cdot {ƒ}_{PWM}$$

I_L bezeichnend hierbei jeweils den Motorstrom; R_DS,on bezeichnet den Leitungswiderstand des jeweiligen Transistors T1-T5; Duty bezeichnet den Tastgrad. U_B bezeichnet die Versorgungsspannung; t_ein bezeichnet die Einschaltzeit und t_aus die Ausschaltzeit beim Schalten des betroffenen Transistors T1-T5; f_PWM bezeichnet die Schaltfrequenz der Pulsweitenmodulation; und U_Body bezeichnet die Spannung über der jeweiligen Freilaufdiode D1-D4 während der Totzeit t_tot1, t_tot2. P_stat,aus berücksichtigt den aktiven Freilauf. Die kurzen Zeitbereiche davor (t_ein) und danach (t_aus) entsprechen einem passiven Freilauf über die Bodydiode.The power loss on the semiconductor switching unit LS1 in the freewheeling phase can be calculated as follows: $$\mathrm{P.}={\mathrm{P.}}_{\mathrm{B.}Ody,ein}+{\mathrm{P.}}_{stat,aus}+{\mathrm{P.}}_{\mathrm{B.}Ody,aus}$$

$$\mathrm{P.}=U_{\mathrm{B.}Ody}\cdot {\mathrm{I.}}_{\mathrm{L.}}\cdot t_{tO\mathrm{<figure-callout\; id="1"\; label="t"\; filenames="DE102020205981A1\_0007.png,DE102020205981A1\_0008.png"\; state="\{\{state\}\}">t</figure-callout>}1}\cdot {ƒ}_{\mathrm{P.}\mathrm{W.}\mathrm{M.}}+{\mathrm{I.}}^2\cdot {\mathrm{R.}}_{\mathrm{D.}\mathrm{S.},On}\cdot \left(1-\mathrm{D.}uty\right)+U_{\mathrm{B.}Ody}\cdot {\mathrm{I.}}_{\mathrm{L.}}\cdot t_{tO\mathrm{<figure-callout\; id="2"\; label="t"\; filenames="DE102020205981A1\_0007.png,DE102020205981A1\_0008.png"\; state="\{\{state\}\}">t</figure-callout>}2}\cdot {ƒ}_{\mathrm{P.}\mathrm{W.}\mathrm{M.}}$$

I _L denotes the motor current in each case; R _{DS, on} denotes the line resistance of the respective transistor T1-T5 ; Duty denotes the duty cycle. U _B denotes the supply voltage; t _a and t denotes the switch _from the switch-off during the switching of the transistor concerned T1-T5 ; f _PWM denotes the switching frequency of the pulse width modulation; and U _Body denotes the voltage across the respective freewheeling diode D1-D4 during the dead time t _tot1 , t _tot2 . P _{stat, off} takes into account the active freewheel. The short time periods before (t _a) and after (t _off) corresponding to a passive free-wheeling diode across the body.

About asymmetrical heating on the semiconductor switching units HS1 , HS2 , LS1 , LS2 the power control module 220 to avoid as they are in accordance with the scheme 7A results, it is proposed in the present case for the integrated actuator 2 for adjusting the vehicle assembly, for example the tailgate 11th who have favourited Semiconductor Switching Units HS1 , HS2 , LS1 , LS2 a current path to operate the adjustment drive 21 to switch alternately in one direction of rotation, as shown schematically in 7B is shown. The semiconductor switching units HS1 , LS2 are thus switched alternately between the on-state and the off-state, so that the same current flow as in 7A results (see the course in 7B below), but the switching operations on the two semiconductor switching units HS1 , LS2 be distributed, as can be seen from the control signals in 7B can be seen above and in the middle.

In particular, they are in on-phases A1 , A3 , A5 , A7 , A9 the semiconductor switching units HS1 , LS2 both in the on-state, so that a current flow over the in 4th and 5 current path shown S1 results. In the switching phases A2 and A6 is the semiconductor switching unit HS1 switched to the off state. In the switching phases A4 , A8 on the other hand is the semiconductor switching unit LS2 switched to the off state.

The semiconductor switching units HS1 , LS2 are thus switched alternately: After a switching process on the one semiconductor switching unit HS1 becomes the other semiconductor switching unit LS2 switched and vice versa. The duty cycle of the current flow results from the ratio of the on-phases A1 , A3 , A5 , A7 , A9 to the total period.

The power loss resulting from the switching processes and the associated loss of energy and thus heating is thus on the semiconductor switching units HS1 , HS2 , LS1 , LS2 distributed, wherein in the freewheeling phase of the semiconductor switching unit LS2 freewheels via the semiconductor switching unit HS2 adjusts, analogous to the switching status according to 6th , and accordingly also a thermal power loss on the semiconductor switching unit HS2 occurs.

The duty cycle during the pulse width modulation is not necessarily constant, but can be adjusted dynamically during operation, as shown 8A , 8B can be seen. This can be done by monitoring the power loss ( 8A) and the energy loss ( 8B) take place.

So can in a first control phase B1 For example, a large duty cycle can be set, for example in a range between 50% and 100%, for example between 80% and 90%. There is a large power loss in the semiconductor switching units HS1 , HS2 , LS1 , LS2 , RPP and a correspondingly large energy loss. Such a duty cycle can be set, for example, during start-up when adjusting the vehicle assembly.

In a subsequent control phase B2 in contrast, a smaller duty cycle is set, for example in a range between 0% and 50%, for example between 20% and 30%. This can correspond to an adjustment after starting. There is less power loss in the semiconductor switching units HS1 , HS2 , LS1 , LS2 , RPP and a correspondingly smaller loss energy that contributes to warming.

The change between the control phases B1 , B2 can take place dynamically during operation, for example using energy monitoring. This can reduce the thermal energy loss to the semiconductor switching units HS1 , HS2 , LS1 , LS2 , RPP can be monitored during operation, for example using a model calculation, in particular using the equation scheme referred to above. If there is excessive heating based on such a loss calculation on one or more of the semiconductor switching units HS1 , HS2 , LS1 , LS2 , RPP detected during operation, it can be from a control phase B1 with a larger duty cycle in a control phase B2 can be switched with a smaller duty cycle.

When controlling the power control module 220 it can result that for a duty cycle in a certain range, for example between 85% and 99.9%, the power loss and energy loss at the semiconductor switching units HS1 , HS2 , LS1 , LS2 , RPP is greater than with a duty cycle of 100%. Used by the logic module 222 If a target duty cycle is determined for adjusting the assigned vehicle assembly with a certain adjustment speed over a certain adjustment path that lies within the predetermined range, a duty cycle can be set corresponding to a limit of the range or outside the range to reduce the power loss and the energy loss. For example, with a target duty cycle between 85% and 99.9%, a duty cycle of 100% can be used to enable thermally optimized operation. A duty cycle that leads to a large power loss and a corresponding heating of the semiconductor switching units HS1 , LS2 , LS1 , LS2 , RPP is thus avoided.

The idea on which the invention is based is not restricted to the exemplary embodiments described above, but can also be implemented in other ways.

An integrated actuator, as described above, can be used to adjust a vehicle assembly in the form of a tailgate or another vehicle door or flap, such as a vehicle side door or a sliding roof, but also to adjust other vehicle assemblies, such as an adjustment assembly a vehicle seat or a ventilation system.

The electromotive adjustment drive can be implemented by an electric motor, for example by a brushless direct current motor with electronic commutation or also by another electric motor.

List of reference symbols

1

Motor vehicle

10

Vehicle body

11th

Vehicle assembly (vehicle door)

110

Hinge axis

2

Integrated actuator

20th

strut

200, 201

section

21

Adjustment drive

22nd

Control electronics

220

Power control module

221

Sensor assembly

222

Logic module

223

Communication module (bus module)

224

Control module

23

casing

3

Control unit (central control)

4th

Bus system

A1-A9

Switching phase

B1, B2

Control phase

D1-D5

diode

HS1, HS2

Semiconductor switching unit

LS1, LS2

Semiconductor switching unit

M.

Ground potential

O

Opening direction

S1

Food path

T1-T5

transistor

x1

Starting position

x2

End position

UB

Supply voltage

QUOTES INCLUDED IN THE DESCRIPTION

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

Patent literature cited

• DE 102007031548 A1 [0008]

Claims (14)

Assembly of a vehicle, with an integrated actuator (2) for adjusting a vehicle assembly (11), the integrated actuator (2) having an electromotive adjustment drive (21) for adjusting the vehicle assembly (11), a power control assembly (220) with an arrangement of semiconductors -Switching units (HS1, HS2, LS1, LS2) for electrically feeding the adjustment drive (21), a logic module (222) for controlling the adjustment drive (21) for performing an adjustment process and a communication module (223) for exchanging data with a higher-level control unit (3), wherein the power control module (220) has a control module (224) for switching the semiconductor switching units (HS1, HS2, LS1, LS2) between an on state and an off state, a first of the semiconductor switching units (HS1, HS2, LS1, LS2) and a second of the semiconductor switching units (HS1, HS2, LS1, LS2) in the on state a current path for electrically feeding the adjustment drive (21) a Forming, characterized in that the control module (224) is designed to feed the adjustment drive (21) in a pulse-width-modulated manner, the first of the semiconductor switching units (HS1, HS2, LS1, LS2) and the second of the semiconductor switching units (HS1, HS2, LS1 , LS2) to switch between the on-state and the off-state according to a predetermined switching scheme in order to interrupt the current path for the pulse-width-modulated feeding of the adjustment drive (21). Assembly according to Claim 1 , characterized in that the integrated actuator (2) has a sensor assembly (221) for detecting an adjustment movement on the adjustment drive (21). Assembly according to Claim 1 or 2 , characterized in that the logic module (222) is designed to evaluate sensor signals for providing an anti-trap functionality, an overvoltage protection functionality and / or an overtemperature protection functionality and to control an adjustment process as a function of sensor signals. Assembly according to one of the Claims 1 until 3 , characterized in that the semiconductor switching units (HS1, HS2, LS1, LS2) have MOSFETs (T1-T4). Assembly according to one of the preceding claims, characterized in that the first of the semiconductor switching units (HS1, HS2, LS1, LS2) is a _{high-side switching unit connected to a supply voltage (U B} ) and the second of the semiconductor switching units (HS1, HS2, LS1, LS2) forms a low-side switching unit connected to a ground potential (M). Assembly according to one of the preceding claims, characterized in that the semiconductor switching units (HS1, HS2, LS1, LS2) together form a full bridge for feeding the adjusting drive (21). Assembly according to one of the preceding claims, characterized in that the control module (224) is designed to feed the adjustment drive (21) with pulse width modulation, the first of the semiconductor switching units (HS1, HS2, LS1, LS2) and the second of the semiconductor switching units ( HS1, HS2, LS1, LS2) to switch between the on-state and the off-state in such a way that a predetermined second number of Switching operations of the second of the semiconductor switching units (HS1, HS2, LS1, LS2) follows. Assembly according to Claim 7 , characterized in that the first predetermined number and the second predetermined number are the same. Assembly according to Claim 7 or 8th , characterized in that the first predetermined number and the second predetermined number is one, so that the first of the semiconductor switching units (HS1, HS2, LS1, LS2) and the second of the semiconductor switching units (HS1, HS2, LS1, LS2) alternate be switched. Assembly according to one of the preceding claims, characterized in that the control module (224) is designed to feed the adjustment drive (21) with pulse width modulation, the first of the semiconductor switching units (HS1, HS2, LS1, LS2) and the second of the semiconductor switching units ( HS1, HS2, LS1, LS2) to switch in a first control phase (B1) with a first duty cycle and in a second control phase with a second duty cycle different from the first duty cycle. Assembly according to Claim 10 , characterized in that the first duty cycle is greater than the second duty cycle. Assembly according to Claim 10 or 11th , characterized in that the power control module (220) is designed to determine a power loss or energy loss of the semiconductor switching units (HS1, HS2, LS1, LS2) and a change between the first control phase (B1) and the second control phase (B2) dependent of the conduction loss or energy loss of the semiconductor switching units (HS1, HS2, LS1, LS2). Assembly according to one of the preceding claims, characterized in that the control module (224) is designed to feed the adjustment drive (21) with pulse width modulation, the first of the semiconductor switching units (HS1, HS2, LS1, LS2) and the second of the semiconductor switching units ( HS1, HS2, LS1, LS2) to switch with a predetermined duty cycle if a target duty cycle required to carry out an adjustment is in an energetically unfavorable range between a predetermined lower duty cycle limit and a predetermined upper duty cycle limit, the predetermined duty cycle being the upper duty cycle limit or the lower Duty cycle limit or a value outside the range between the predetermined lower duty cycle limit and the predetermined upper duty cycle limit. A method for performing an adjustment process of a vehicle assembly (11), comprising: adjustment of the vehicle assembly (11) by means of an integrated actuator (2) which has an electromotive adjustment drive (21), a power adjustment assembly (220) with an arrangement of semiconductor switching units (HS1, HS2, LS1, LS2) for electrically feeding the adjustment drive (21), a logic module (222) for controlling the adjustment drive (21) for performing the adjustment process and a communication module (223) for exchanging data with a higher-level control unit (3), wherein a control module (224) of the power control module (220) switches the semiconductor switching units (HS1, HS2, LS1, LS2) between an on state and an off state and a first of the semiconductor switching units (HS1, HS2, LS1, LS2) ) and a second of the semiconductor switching units (HS1, HS2, LS1, LS2) in the on state form a current path for electrically feeding the adjustment drive (21), thereby marked hnet that the control module (224) for pulse width modulated feeding of the adjustment drive (21) the first of the semiconductor switching units (HS1, HS2, LS1, LS2) and the second of the semiconductor switching units (HS1, HS2, LS1, LS2) according to a predetermined Switching scheme switches between the on-state and the off-state in order to interrupt the current path for pulse-width-modulated feeding of the adjustment drive (21).

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