WO2022233576A1

WO2022233576A1 - Device for controlling an electrical component of a vehicle and method for operating the device

Info

Publication number: WO2022233576A1
Application number: PCT/EP2022/060497
Authority: WO
Inventors: Tobias DIRLMEIER; Philipp Eck; Imre Fekete
Original assignee: Webasto SE
Priority date: 2021-05-04
Filing date: 2022-04-21
Publication date: 2022-11-10
Also published as: DE102021111426A1

Abstract

The invention relates to a device (10) for controlling an electrical component (12) of a vehicle (24), comprising a control input (10a) for receiving an input signal, a signal output (10b) for controlling the electrical component (12) by means of an output signal, a digital/analogue converter element (16) for generating a primary signal depending upon the received input signal, and an amplifier element (22) for generating the output signal depending upon the primary signal, the output signal having an AC voltage with a frequency and/or an amplitude, and the electrical component (12) being controllable depending upon the AC voltage of the output signal. The invention also relates to a system having an intelligent glass pane (12) and a device (10) according to any of the preceding claims for controlling the glass pane (12) and to a method for operating a device (10) for controlling an electrical component (12) of a vehicle (24).

Description

description

Device for controlling an electrical component of a vehicle and method for operating the device

The invention relates to a device for controlling an electrical component of a vehicle and a method for operating the device.

Metal-oxide-semiconductor field effect transistors (MOSFET), bipolar transistors or bipolar transistors with insulated gate electrodes (IGBT) are often used to amplify electrical signals in the automotive sector. Typically, square-wave signals are used as input signals, which are provided by a control device or a pre-stage, for example. Such signals are easy to generate and adapt.

Voltage converters can also be used to amplify signals, such as DC-AC converters, in which the signals are converted by means of inductors and transformers.

DE 102016214292 A1 describes a control for an “intelligent glass pane”. A cycloinverter is used to provide the output voltage.

In the known methods, problems with regard to electromagnetic compatibility (EMC) occur in many cases. Broadband interference is caused by steep signal edges. This is due, among other things, to the fast switching of MOSFETs, which can be necessary in particular for the transmission of large electrical powers.

It is the object of the invention to provide a device for controlling an electrical component that enables improved electromagnetic compatibility. In particular, electromagnetic interference should be avoided in the long and medium wave ranges as well as in the VHF range.

This object is achieved by a device of the type mentioned with the features of claim 1. Advantageous configurations and developments of the invention are set out in the dependent claims.

The device for activating an electrical component of a vehicle comprises a control input for receiving an input signal and a signal output for activating the electrical component by means of an output signal. It also includes a digital-to-analog converter element for generating a primary signal as a function of the received input signal and an amplifier element for generating the output signal as a function of the primary signal. In this case, the output signal has an alternating voltage with a frequency and/or an amplitude. In this case, the electrical component can also be controlled as a function of the AC voltage of the output signal.

It is a fundamental idea of the invention to improve the electromagnetic compatibility of the control of an electrical component by avoiding or specifically setting particularly rapid switching between voltage values of the output signal. This is done by means of a signal generator and a conversion from a digital to an analog signal, with both the initially provided signal and the amplification being able to be determined very precisely by a suitable choice and/or setting of the further elements.

As a result, parameters of a voltage transition can advantageously be adjusted. In particular, a narrow-band signal is obtained as a result. The electromagnetic compatibility can therefore advantageously be selected appropriately for the respective area of use.

Furthermore, the device can be provided in a particularly cost-effective manner since common and inexpensive components are used.

In addition, the device can be operated at relatively low voltages, in which case, in particular, any risk to human health can be ruled out. Complex and expensive protective measures can therefore be reduced.

The digital-to-analog converter element is connected in particular to the control input and can be designed in a manner known per se. In particular, it is set up to generate an analog primary signal based on a received digital input signal. The amplifier element is in particular upstream of the signal output or connected between the digital-to-analog converter element and the signal output. It can also be designed in a manner known per se. It is set up to generate the output signal using the analog primary signal output by the digital-to-analog converter.

In one embodiment of the device, the input signal is in the form of a digital signal and the primary signal is in the form of an analog signal. As a result, the output signal can advantageously be formed particularly easily by a digital control device. Furthermore, the analog primary signal can advantageously be used directly to amplify and control the electrical component.

In a further embodiment, the amplifier element comprises a pre-stage element for amplifying an amplitude and an end-stage element for amplifying an electrical power. As a result, the output signal can advantageously be generated very precisely with available resources. An operational amplifier (OP amplifier), for example, can be used as a pre-stage element.

In a development, the electrical component can be set and/or adjusted using the output signal. This allows the device to be used advantageously to perform various adjustment tasks.

In one embodiment, the electrical component includes a smart glass pane, an LED headlight, or an electric motor.

In this sense, an “intelligent glass pane” (“smart glass”) can be referred to as glazing whose tint and/or light transmission can be changed by means of an electrical voltage and/or an electrical current. In this context, for example, SPD glass (Suspended Particle Device) and PDLC glass (Polymer Dispersed Liquid Crystal Device) are known per se.

When driving an electric motor, energy can be supplied directly via the output signal in one embodiment. The output signal can be adjusted in various ways, in particular by means of a suitable input signal, so that desired operating parameters of the electric motor are achieved. For example, a specific speed and/or power of the electric motor can be achieved by adjusting the output signal in a suitable manner. The device can be found here advantageously control the motor very specifically, for example when used in different contexts and with different needs. The operation of the electric motor can also be adapted to the current requirements for the performance of the motor and the desired electromagnetic compatibility.

In a further embodiment, the output signal includes an AC voltage, in particular with a frequency between 1 Hz and 1 MHz, for example between 100 kHz and 600 kHz. As a result, the device can advantageously be operated in a frequency range that is highly relevant for the activation of various electrical components of a vehicle. With further development, other frequencies can be reached.

In one development, the output signal essentially has a square shape, a sawtooth shape, a triangular shape or a sinusoidal shape. The output signal can also have mixed forms, such as a superimposition of different signal forms. In the case of triangular and sinusoidal shapes in particular, the steep edges that are usually used in switching processes, such as those that occur with square-wave signals, are advantageously avoided. While steep temporal gradients of voltage or current can lead to broadband EMC-relevant interference, this is avoided or reduced with flatter edges.

In particular, the signal form of the analog primary signal or of the output signal is formed as a function of the digital input signal. The signal form can therefore also be selected or set using the input signal.

In one embodiment, a signal form, in particular a steepness of the edges, of the output signal can be selected or set as a function of a request signal. In particular, the device can be set up to receive the request signal and to adapt the signal form of the primary signal and/or the output signal as a function thereof.

For example, depending on the current requirements, a suitable signal shape can be obtained in this way. For example, when driving a motor, fast switching with correspondingly steep flanks of the voltage curve may be necessary in order to achieve higher performance. With flatter flanks, on the other hand, better electromagnetic compatibility can be achieved. Therefore, in a situation that requires short-term retrieval of higher performance, depending on the context, a poorer EMC can be accepted.

The system of the invention comprises an intelligent glass pane or an electrically switchable glass pane, and a device according to the present description for driving the glass pane.

In the method for operating a device for activating an electrical component of a vehicle, a digital input signal is received and an analog primary signal is generated as a function of the received input signal. An output signal is generated as a function of the primary signal by means of an amplifier element, the electrical component being controlled by means of the output signal and the output signal having an AC voltage with a frequency and/or an amplitude.

The method is designed to operate the device. It therefore has the same advantages as the device according to the invention.

The invention is explained in more detail below with reference to the attached drawings.

Show it:

FIG. 1 shows an exemplary embodiment of the device in a vehicle;

FIG. 2 shows a diagram with a control signal;

FIG. 3 shows a detailed view of the device; and

FIGS. 4 to 6 diagrams of exemplary primary and output signals.

An exemplary embodiment of the device in a vehicle is explained with reference to FIG.

The vehicle 24 includes an electrical component 12, in the exemplary embodiment a smart glass pane 12.

The intelligent glass pane 12 is designed in a manner known per se in such a way that its transparency and/or tint can be adjusted as a function of an applied voltage.

The vehicle 24 also has a control unit 14 which is coupled to the electrical component 12 via a device 10 for controlling the latter. The device 10 has a digital-to-analog converter element 16 which is coupled to a control input 10a of the device 10 .

An amplifier element 22 , which in turn comprises a pre-stage element 18 and a power stage element 20 , is coupled to the digital-to-analog converter element 16 .

The amplifier element 22 is also coupled to the electrical component 12 via a signal output 10b of the device 10 .

The control unit 14 is set up to generate a digital control signal and to transmit it to the device 10 . The digital control signal can be generated, for example, as a function of a user input that makes a setting for a specific parameter of the electrical component 12 .

The control signal is received by the digital to analog converter element 16 . An analogue primary signal is generated on the basis of the digital control signal.

The analog primary signal is then amplified by the amplifier element 22.

In this case, the pre-stage element 18 comprised by the amplifier element 22 is set up to amplify the amplitude of the primary signal. The output stage element 20 then amplifies the power of the signal, which is finally transmitted as an output signal to the electrical component 12 via the signal output 10b.

The output signal here has an AC voltage with a specific frequency and amplitude and a specific signal form. The electrical component 12 is set as a function of these parameters of the output signal.

In further exemplary embodiments, other electrical components 12 of vehicle 10 can be provided, which can be controlled by means of the analog output signal. For example, the electrical component 12 may comprise an LED headlight, an electric motor or another device of the motor vehicle 24 that can be controlled by means of an output signal that can be generated by the device 10 .

FIG. 2 shows an example of a drive signal 30 as can be used in many cases. The diagram shows the course of a voltage in dependence on time.

The signal form is essentially a square-wave voltage. In this case, a quick switch is made between a lower voltage and an upper voltage. During switching, the voltage runs along steep rising 32 or falling edges 34.

A schematic detailed view of the device 10 is explained with reference to FIG.

The sections in which the digital-to-analog converter element 16, the pre-stage element 18 and the end-stage element 20 are formed are indicated in the circuit diagram.

The digital-to-analog converter element 16 is designed in a manner known per se.

In the exemplary embodiment, the pre-stage element 18 comprises an operational amplifier (op-amplifier) designed in a manner known per se.

The output stage element 20 is again also designed in a manner known per se.

Elements known per se from electronics and circuit technology can therefore advantageously be used. In the combination of the invention, these elements allow the generation of a freely configurable signal, in particular with a signal shape that can be easily specified. In this way, for example, an optimal EMC behavior is achieved.

In particular, discrete components are used here, which allow the device 10 to be implemented in a particularly cost-efficient manner.

Other configurations of the amplifier element 22 and its parts 18, 20 can also be provided.

With reference to FIGS. 4 to 6, examples of primary and output signals as they can appear in the device 10 are explained.

In the case shown in Figure 4, a square-wave voltage with direct transitions between a lower voltage level and an upper voltage level than Output signal generated. The curves of the primary signal 42 and the amplified output signal 44 are shown offset in relation to one another in the vertical direction in the diagram. When the amplitude of the primary signal 42 generated by the digital-to-analog converter element 16 is amplified, the signal is also inverted.

In the case shown in FIG. 5, the signal form of the case shown in FIG. 4 was adapted in such a way that a triangular voltage is now present. The voltage is changed linearly between a lower voltage level and an upper voltage level as the output signal. The curves of the primary signal 52 and the amplified output signal 54 are shown offset in relation to one another in the vertical direction in the diagram. When the amplitude of the primary signal 52 generated by the digital-to-analog converter element 16 is amplified, the signal is also inverted.

Finally, in the case shown in Figure 6, the waveform is that of a sine wave. This means that the voltage is changed between a lower voltage level and an upper voltage level along a sine or cosine. The curves of the primary signal 62 and the amplified output signal 64 are shown offset in relation to one another in the vertical direction in the diagram. When the amplitude of the primary signal 62 generated by the digital-to-analog converter element 16 is amplified, the signal is also inverted.

Other signal forms are of course also conceivable and can be converted into an analog primary signal by means of the digital-to-analog converter element 16 .

A particular advantage of the device 10 is that practically any signal form can be set by the control unit 14 together with the digital-to-analog converter element 16 . In addition, the steps of amplifying the primary signal in order to obtain the output signal can be designed flexibly. In particular, the amplification of the voltage and/or the current through the pre-stage element 18 and/or the end-stage element 20 can be selected in a particularly flexible manner. The setting of the signal form offers good access to characteristics of electromagnetic compatibility, so that in particular interference in certain specified frequency ranges can be avoided and/or interference can only be permitted on a case-by-case basis in order to be able to output greater power, for example.

In the embodiment, the device 10 is configured to a to output an output signal with a frequency of between about 35 kHz to 80 kHz.

In further exemplary embodiments, other frequencies or frequency ranges can be provided for the output signal, for example in a range from approximately 1 Hz to the kHz range, ie in a medium wave or long wave range. In further exemplary embodiments, frequencies between 100 and 600 kHz can be provided.

The voltages achieved in this example range up to 32 V peak voltage corresponding to 64 V peak-to-peak voltage. In particular, the device 10 is operated in the low-voltage range in order to minimize health hazards.

Unlike other devices where higher voltages are achieved, the elements of device 10, particularly the digital-to-analog

Converter element 16 and the amplifier element 22 can be made simpler. Less expensive elements can be used so that the device 10 itself can also be manufactured more efficiently. In particular, such a cost advantage is clear in the case of discrete circuit parts compared to integrated components (integrated circuit, IC) and/or transformers.

LIST OF REFERENCE NUMERALS 10 Device

10a control input

10b signal output

12 electrical component; smart pane

14 control unit 16 digital-to-analog converter element

18 precursor element

20 power amp element

22 amplifier element

24 vehicle 30 activation signal

32 Rising edge

34 Falling edge

42 primary signal

44 Output signal (amplified) 52 Primary signal

54 output signal (amplified)

62 primary signal

64 output signal (amplified)

Claims

patent claims

First device (10) for controlling an electrical component (12) of a vehicle (24), comprising a control input (10a) for receiving an input signal; a signal output (10b) for driving the electrical component (12) by means of an output signal; a digital to analog converter element (16) for generating a primary signal in response to the received input signal; and an amplifier element (22) for generating the output signal in dependence on the primary signal; wherein the output signal comprises an AC voltage with a frequency and/or an amplitude; and the electrical component (12) can be controlled as a function of the alternating voltage of the output signal.

2. Device (10) according to claim 1, characterized in that the input signal is in the form of a digital signal and the primary signal is in the form of an analog signal.

3. Device (10) according to any one of the preceding claims, characterized in that the amplifier element (22) comprises a pre-stage element (18) for amplifying an amplitude and an end-stage element (20) for amplifying an electrical power.

4. Device (10) according to one of the preceding claims, characterized in that the electrical component (12) can be set and/or adjusted using the output signal.

5. Device (10) according to any one of the preceding claims, characterized in that the electrical component (12) is a smart glass pane, an LED Includes headlights or an electric motor.

6. Device (10) according to one of the preceding claims, characterized in that the output signal comprises an AC voltage, in particular with a frequency between 1 Hz and 1 MHz, for example between 100 kHz and 600 kHz.

7. Device (10) according to one of the preceding claims, characterized in that the output signal essentially has a rectangular shape, a sawtooth shape, a triangular shape or a sinusoidal shape.

8. Device (10) according to one of the preceding claims, characterized in that a signal form of the output signal can be selected as a function of a request signal.

9. System with a smart glass pane (12) and a device (10) according to any one of the preceding claims for driving the glass pane (12).

10. A method for operating a device (10) for controlling an electrical component (12) of a vehicle (24), wherein a digital input signal is received; an analog primary signal is generated in dependence on the received input signal; and an output signal is generated in dependence on the primary signal by means of an amplifier element (22); wherein the electrical component (12) is controlled by means of the output signal; wherein the output signal comprises an AC voltage with a frequency and/or an amplitude.