DE102021213729A1 - Sensor device for a drive device for a vehicle, drive device for a vehicle and method for operating a sensor device - Google Patents

Abstract

Sensor device (104) for a drive device (102) for a vehicle (100). The sensor device (104) has a high-voltage line (112) for electrically connecting an electric machine (106) for driving the vehicle (100) and an inverter (108) for providing an alternating current for operating the electric machine (106), the high-voltage line (112) has an electrically conductive core for conducting the alternating current and a screen surrounding the core for shielding the core. A shield voltage is induced in the shield when the alternating current is conducted through the core. Furthermore, the sensor device (104) has a converter device (114) with an input interface (116), which is electrically connected to the shield of the high-voltage line (112), and an output interface (118) to a sensor unit (109) of the drive device (102). , wherein the converter device (114) is designed to convert the screen voltage into an operating voltage for the sensor unit (109).

Description

The present invention relates to a sensor device for a drive device for a vehicle, to a drive device for a vehicle and to a method for operating a sensor device.

Sensors are used nowadays in the automotive sector, for example for security and monitoring purposes, and require a corresponding power supply. Sensors in the vehicle are usually supplied with energy directly via components, such as evaluation units, and thus at least indirectly via the on-board battery.

Against this background, the present invention creates an improved sensor device for a drive device for a vehicle, an improved drive device for a vehicle and an improved method for operating a sensor device according to the main claims. Advantageous configurations result from the dependent claims and the following description.

The approach presented makes it possible to relieve an energy supply device, for example a battery, and thus to keep a vehicle electrical system energy balance stable, for example. For this purpose, sensors, for example high-voltage sensors, can be independently supplied with electrical energy.

A sensor device for a drive device for a vehicle is presented, the sensor device having a high-voltage line for electrically connecting an electric machine for driving the vehicle and an inverter for providing an alternating current. The high-voltage line has an electrically conductive core for conducting the alternating current and a screen surrounding the core for shielding the core, a screen voltage being induced in the screen when the alternating current is passed through the core. Furthermore, the sensor device has a converter device with an input interface, which is electrically connected to the shield of the high-voltage line, and an output interface to a sensor unit, the converter device being designed to convert the shield voltage into an operating voltage for the sensor unit.

The vehicle can be a motor vehicle, for example in the form of a passenger car, truck or commercial vehicle. The vehicle can also be configured as a single-track vehicle. The vehicle can be driven at least partially electrically. The drive device can be connected to an on-board network of the vehicle. The high-voltage line can be used, for example, as a phase for a three-phase alternating current to operate the electrical machine. The electric machine can be designed as an electric motor or as an electric drive, for example. The high-voltage line has the core, which can have, for example, a plurality of wires or stranded electrical cables. The shield voltage that occurs in an operating state of the drive device and is otherwise unused can now advantageously be used to operate the sensor unit. This can advantageously improve the energy balance of the drive device.

According to one embodiment, the sensor device can have the sensor unit, which can be connected to the output interface of the converter device. The sensor unit can, for example, be a temperature sensor for detecting a temperature of the high-voltage cable, a voltage sensor for detecting an electrical voltage present at the core of the high-voltage cable, a current sensor for detecting the alternating current flowing through the core, a speed sensor for detecting a motor speed of the electrical machine, or something else have sensor. For example, the sensor unit can include at least one high-voltage sensor. Advantageously, the sensor unit can be operated using the screen voltage, so that the sensor unit can advantageously supply itself with electrical energy independently and thus, for example, does not additionally load the battery of the vehicle.

Furthermore, the sensor device can have a connecting line that can connect a contact point of the shield to the input interface. The connecting line can be realized, for example, as a cable or as an electrically conductive connection, for example as a wire. Using the connecting line and the contact point, the screen voltage can be tapped directly on the screen. As a result, losses can be kept low. Advantageously, a shield current induced in the shield, or at least part of the shield current, can be branched off directly in order to generate the operating voltage for the sensor unit.

According to one embodiment, the contact point can be arranged on a middle third of a length of the high-voltage line. Advantageously, effects acting on the shield voltage in the middle of the high-voltage line Connection points of the high-voltage cable are neglected.

The converter device can be designed to provide the operating voltage as a DC voltage. Advantageously, the converter device can provide the operating voltage in such a way that it can be used directly, ie without further adjustment, for operating the sensor unit.

Accordingly, the converter device can be designed to convert a voltage level of the shield voltage into an adjusted voltage level of the operating voltage. For example, the voltage level can be increased or decreased so that the operating voltage can have a voltage level required for the sensor unit.

The converter device can have a transformer unit which can be coupled to the input interface on the input side. Furthermore, the transformer unit can be designed to be able to convert the shield voltage into an intermediate voltage. Advantageously, the screen voltage and the intermediate voltage can be electrically isolated from one another.

According to one embodiment, the transformer unit can have a diode in order to be able to provide the intermediate voltage as a direct voltage. The diode can advantageously prevent energy from being able to be transmitted bidirectionally.

The transformer unit can have two coils, for example, of which the coil on the input side can be connected between the input interface and ground. In this way, the screen voltage can be optimally used.

According to one specific embodiment, the converter device can have a converter which is coupled to the output interface and can be designed to be able to convert the intermediate voltage into the operating voltage. The converter can also be referred to as a converter, for example, and is designed, for example, to convert AC voltage into DC voltage. This means that the intermediate voltage can be an AC voltage, for example, and the operating voltage for the sensor unit can be a DC voltage.

Furthermore, according to one embodiment, the converter can be designed as a step-down converter. In this case, the step-down converter can be designed, for example, to convert the intermediate voltage, which has a higher voltage level than the operating voltage, for example, into the operating voltage. This can advantageously prevent the sensor unit from being overloaded and thereby damaged, for example.

A drive device for a vehicle is also presented, the drive device having a sensor device in an aforementioned variant, the electric machine for driving the vehicle, and an inverter.

The electrical machine can have a housing, for example, which can enclose a stator and a rotor of the electrical machine.

According to one embodiment, the drive device can have an energy supply device for providing the electrical energy, it being possible for the energy supply device to be connected to the inverter. The energy supply device can be in the form of a power source, for example a battery. The drive device can thus be connected to an on-board network of the vehicle. Using the inverter, a DC voltage provided by the energy supply device can be converted into an AC voltage in a known manner. Known machines such as those used in electrically driven vehicles can be used for the electric machine.

Furthermore, a method for operating a sensor device is presented in an aforementioned variant, the method comprising a conducting step and a converting step. In the conducting step, an alternating current is passed through a core of a high-voltage line for electrically connecting an electric machine for driving the vehicle and an inverter for providing an alternating current for operating the electric machine, the high-voltage line having the electrically conductive core for conducting the alternating current and a den Having a core surrounding shield for shielding the core, wherein a shield voltage is induced in the shield. In the conversion step, the screen voltage is converted into an operating voltage for a sensor unit.

With the method, an interference current acting during operation of the drive device can advantageously be used via the shield voltage in order to operate the sensor device. For this purpose, the induced interference current can be branched off via the input interface of the converter device, converted accordingly and used the. By using the interference current, the sensor unit can be supplied with power independently.

• 1 eine schematische Darstellung eines Fahrzeugs mit einer Antriebsvorrichtung gemäß einem Ausführungsbeispiel;
• 2 eine schematische Darstellung einer Sensorvorrichtung gemäß einem Ausführungsbeispiel; und
• 3 ein Ablaufdiagramm eines Ausführungsbeispiels eines Verfahrens zum Betreiben einer Sensorvorrichtung.

The invention is explained in more detail by way of example with reference to the attached drawings. Show it:

• 1 a schematic representation of a vehicle with a drive device according to an embodiment;
• 2 a schematic representation of a sensor device according to an embodiment; and
• 3 a flowchart of an embodiment of a method for operating a sensor device.

In the following description of preferred exemplary embodiments of the present invention, the same or similar reference symbols are used for the elements which are shown in the various figures and have a similar effect, with a repeated description of these elements being dispensed with.

1 shows a schematic representation of a vehicle 100 with a drive device 102 according to an embodiment. According to this exemplary embodiment, vehicle 100 is implemented as a two-track motor vehicle that is designed, for example, to transport people and/or objects. Vehicle 100 has drive device 102 , which has a sensor device 104 , an electric machine 106 and an inverter 108 . The sensor device 104 is implemented here by way of example as part of the drive device 102 and is designed, for example, to operate a sensor unit 109 .

The electric machine 106 is designed to drive the vehicle 100 and is designed or usable accordingly, for example as a vehicle drive in the form of an electric motor. The inverter 108 is electrically connected to the electric machine 106 using the sensor device 104 and is configured to provide an AC voltage for operating the electric machine 106 . The inverter 108 is also referred to as an inverter, for example. Furthermore, drive device 102 optionally has an energy supply device 110 that is designed to provide electrical energy that is used by inverter 108 to provide the AC voltage for operating electrical machine 106 . The energy supply device 110 is implemented as a battery, for example, which is electrically connected to the inverter 108 .

Sensor device 104 has a high-voltage line 112 for electrically connecting electric machine 106 and inverter 108 . The high-voltage line 112 in turn has an electrically conductive core for conducting the alternating current provided by the inverter 108 and a screen for shielding the core, as shown in 2 to be discribed. When the alternating current is conducted through the core of the high-voltage line 112 in an operating state of the drive device 102, a shield voltage is induced in the shield. The induced screen voltage and thus a corresponding screen current induced in the screen is used to operate the sensor unit 109 .

For this purpose, the sensor device 104 has a converter device 114 with an input interface 116 which is electrically conductively connected to the shield of the high-voltage line 112 . The converter device 114 also has an output interface 118 to the sensor unit 109 . In this case, the converter device 114 is designed to convert the shield voltage tapped via the input interface 116 into an operating voltage for the sensor unit 109 . According to one embodiment, the converter device 114 is designed to provide the operating voltage as a DC voltage. In this case, the converter device 114 only optionally converts a voltage level of the shield voltage into an adapted voltage level of the operating voltage. This means that the voltage level of the shield voltage is increased or decreased, for example, in order to operate the sensor unit 109 accordingly with the adjusted voltage level. To convert the screen voltage into the operating voltage, the conversion device 114 can be implemented in a suitable known manner.

By way of example only, the converter device 114 has a transformer unit 120 and a converter 122 . The transformer unit 120 is coupled to the input interface 116 on the input side and is designed to convert the shield voltage into an intermediate voltage. The converter 122, for example in the form of a step-down converter (or step-up converter), is designed to convert the intermediate voltage into the operating voltage and to make it available at the output interface 118.

For example, the transformer unit 120 is connected to ground 124 on the input side and has two inductively coupled coils 126 . An input side of the coils 126 is connected between the input interface 116 and ground 124 . The input side of the coils 126 can be connected directly to ground 124 or, for example, via a The housing of the electric machine 106 can be connected to ground 124 . According to one exemplary embodiment, the transformer unit 120 also has a diode 128 in order to provide the intermediate voltage as a DC voltage. The diode 128 is connected, for example, between a terminal of one of the coils 126 on the output side and a terminal of the converter 122 .

According to one exemplary embodiment, sensor unit 109 is implemented as part of sensor device 104 . The sensor unit 109 is electrically connected to the output interface 118 and is supplied with the operating voltage via the output interface 118 . According to one exemplary embodiment, the sensor unit 109 is supplied with the operating voltage generated from the shield voltage exclusively via the output interface 118 .

Sensor unit 109 is designed, for example, as a sensor for detecting a temperature, an electrical voltage, an electrical current and/or a speed or a position of a rotor of electrical machine 106 . For example, a corresponding sensor of the sensor unit 109 can be integrated in the inverter 108 or can be arranged on a casing of the high-voltage line 112 or on the electrical machine 106 .

According to one exemplary embodiment, sensor device 104 has a connecting line 130 that connects a contact point 132 arranged directly on the shield of high-voltage line 112 to input interface 116 . In this case, the contact point 132 is only optionally arranged on a middle third of a length of the high-voltage line 112 . Alternatively, however, the contact point 132 can also be placed elsewhere. According to one exemplary embodiment, the connecting line 130 is formed in order to connect the contact point 132 directly, ie without including further components or electrical parts, to the input interface 116, here a connection of the coils 126 on the input side.

In other words, the approach described enables an autonomous sensor supply by means of a line-bound induced shielding current, so that the energy balance of the overall system is no longer influenced by additional small sensors, for example. This means that the energy supply device 110 embodied as a battery, for example, is further relieved and the vehicle electrical system energy balance of the vehicle 100 is thus kept stable, in that high-voltage sensors, for example, which can be comprised by the sensor unit 109 , are supplied autonomously with regard to the electrical energy balance. For this purpose, the operation of the unit, here the drive device 102, induces a current on the shielded high-voltage line 112 and part of the induced shield current of the high-voltage line 112 is used to supply the sensor point, which is referred to as sensor unit 109 according to this exemplary embodiment. In this way, the branched shielding current is transformed and electrical safety is established. On an output side, for example, the diode 128 protects the system so that the energy within the converter device 114 is not transmitted bidirectionally. In order to supply the sensor unit 109 with a corresponding voltage level, the screen voltage is converted by the converter 122 according to one exemplary embodiment and thus supplies the sensor unit 109. The converter 122 is embodied as a DC/DC converter, for example as a step-down converter.

2 10 shows a schematic representation of a sensor device 104 according to an exemplary embodiment. In the 2 The sensor device 104 shown corresponds or is at least similar to that in 1 described sensor device 104. The sensor device 104 illustrated according to this exemplary embodiment is also implemented or can be implemented, for example, as part of a drive device, as is shown, for example, in 1 was described. According to this exemplary embodiment, only the high-voltage line 112 is shown in a cross section in order to show the electrically conductive core 200 in an interior of the high-voltage line 112 and to show the shield 202 for shielding the core 200 , which surrounds the core 200 . The contact point 132 of the screen 202 is also electrically conductively connected to the input interface 116 of the converter device 114 according to this exemplary embodiment. The converter device 114, or the transformer unit 120 of the converter device 114, has the coils 126, of which the input side is connected to the ground 124 according to this exemplary embodiment. According to this exemplary embodiment, the converter device 114 is also connected between the high-voltage line 112 and the sensor unit 109 .

3 shows a flowchart of an embodiment of a method 300 for operating a sensor device. The method 300 is performed, for example, using a sensor device as described in one of 1 until 2 was described. The method 300 includes a step 302 of routing and a step 304 of conversion. In step 302 of conduction, an alternating current provided by an inverter is conducted through a core of the high-voltage line to an electric machine in order to drive the electric machine. Alternatively, the alternating current from the electric cal machine provided when the electric machine is operated as a generator. The alternating current induces a shield voltage and a corresponding shield current in a shield of the high-voltage cable. In step 304 of conversion, the shield voltage and thus at least part of the shield current is used to generate an operating voltage for a sensor unit.

Reference List

100

vehicle

102

drive device

104

sensor device

106

electric machine

108

inverter

109

sensor unit

110

power supply device

112

high-voltage line

114

converter device

116

input interface

118

output interface

120

transformer unit

122

converter

124

Dimensions

126

Wash

128

diode

130

connection line

132

contact point

200

electrically conductive core

202

umbrella

300

Method for operating a sensor device

302

step of guiding

304

step of converting

Claims (14)

Sensor device (104) for a drive device (102) for a vehicle (100), the sensor device (104) having the following features: a high-voltage line (112) for electrically connecting an electric machine (106) for driving the vehicle (100) and an inverter (108) for providing an alternating current for operating the electric machine (106), the high-voltage line (112) having an electrically conductive core (200) for conducting the alternating current and a shield (202) surrounding the core (200) for shielding the core (200), a shield voltage being induced in the shield (202) when the alternating current is passed through the core (200). becomes; and a converter device (114) with an input interface (116), which is electrically connected to the shield (202) of the high-voltage line (112), and with an output interface (118) to a sensor unit (109) of the drive device (102), the converter device (114) is designed to convert the screen voltage into an operating voltage for the sensor unit (109). Sensor device (104) according to claim 1 , With the sensor unit (109), which is connected to the output interface (118) of the converter device (114). Sensor device (104) according to one of the preceding claims, with a connection line (130) which connects a contact point (132) of the screen (202) to the input interface (116). Sensor device (104) according to claim 3 , wherein the contact point (132) is arranged on the high-voltage line (112). Sensor device (104) according to one of the preceding claims, wherein the converter device (114) is designed to provide the operating voltage as a DC voltage. Sensor device (104) according to one of the preceding claims, wherein the converter device (114) is designed to convert a voltage level of the shield voltage into an adjusted voltage level of the operating voltage. Sensor device (104) according to one of the preceding claims, wherein the converter device (114) has a transformer unit (120) which is coupled to the input interface (116) on the input side, and wherein the transformer unit (120) is designed to convert the screen voltage into an intermediate voltage to convert Sensor device (104) according to claim 7 , wherein the transformer unit (120) comprises a diode (128) to provide the intermediate voltage as a DC voltage Sensor device (104) according to one of Claims 7 or 8th wherein an input coil of the transformer unit (120) is connected between the input interface (116) and ground (124). Sensor device (104) according to one of Claims 7 until 9 , wherein the converter device (114) has a converter (122) which is coupled to the output interface (118) and is designed to convert the intermediate voltage into the operating voltage. Sensor device (104) according to claim 10 , wherein the converter (122) is designed as a buck converter. Drive device (102) for a vehicle (100), the drive device (102) having the following features: a sensor device (104) according to any one of the preceding claims; the electric machine (106) for propelling the vehicle (100); and the inverter (108). Drive device (102) according to claim 12 , With an energy supply device (110) for providing the electrical energy, wherein the energy supply device (110) is connected to the inverter (108). Method (300) for operating a sensor device (109) according to one of Claims 1 until 11 , wherein the method (300) comprises the following steps: passing (302) an alternating current through a core (200) of a high-voltage line (112) for electrically connecting an electric machine (106) for driving the vehicle (100) and an inverter (108 ) for providing an alternating current for operating the electrical machine (106), the high-voltage line (112) having the electrically conductive core (200) for conducting the alternating current and a screen (202) surrounding the core (200) for shielding the core (200) wherein a screen voltage is induced in the screen (202); and converting (304) the screen voltage into an operating voltage for a sensor unit (109).

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