Apparatus and a method for discharging a capacitor

A method for discharging a capacitor. An active discharge circuit is connected in parallel with the capacitor. An interface provides a signal connection between a message-based communication system and the active discharge circuit. The interface comprises at least one input for receiving messages from the message-based communication system. The interface comprises a wake-up functionality. The at least one input comprises an input for the wake-up functionality. The method comprises: receiving at the input for the wake-up functionality a disable discharge command message of said messages for the disabling of the discharge of the capacitor, wherein upon cessation of the disable discharge command message the discharge of the capacitor is enabled. An apparatus for the discharge of a capacitor, wherein the apparatus comprises the interface and the active discharge circuit connectable in parallel with the capacitor.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a National Stage Patent Application (filed under 35 § U.S.C. 371) of PCT/SE2021/050837, filed Aug. 27, 2021, of the same title, which, in turn claims priority to Swedish Patent Application No. 2051075-6 filed Sep. 15, 2020, of the same title; the contents of each of which are hereby incorporated by reference.

FIELD OF THE INVENTION

Aspects of the present invention relate to a method for discharging a capacitor. Aspects of the present invention also relate to an apparatus for the discharge of a capacitor.

BACKGROUND OF THE INVENTION

In general, electrical devices, such as electronic components, electrically connected to an electrical system, may be equipped with one or more capacitors as an electrical buffer. This may, for example, be the case for electrical devices connected to an electrical system of a vehicle, such as a hybrid vehicle or an electric vehicle. An electrical system of a vehicle, which be referred to as a vehicle electrical system, or a vehicle high voltage system (VCB), may be electrically connected, or connectable, to the electric battery or electric batteries of the vehicle, which may be provided as one or more electric battery packs. For example, a vehicle electrical system may transfer electric power or electric current between various electrical devices or units included in the vehicle, for example the hybrid vehicle or the electric vehicle. A vehicle electrical system may transfer electric power or electric current from the electric battery to the electric motor/motors driving, or propelling, the vehicle. In some cases, occasionally the above-mentioned capacitor should be discharged, for example for safety reasons.

SUMMARY OF THE INVENTION

The inventors of the present invention have found drawbacks in conventional solutions for discharging a capacitor. For example, the communication or control system assigned to control the discharge of the capacitor may require additional cable, or wire, harness to implement the control or management of the discharge of the capacitor.

An object of the invention is to provide a solution which mitigates or solves the drawbacks and problems of conventional solutions.

The above and further objects are solved by the subject matter of the independent claims. Further advantageous embodiments of the invention can be found in the dependent claims.

According to a first aspect of the invention, the above mentioned and other objects are achieved with a method for discharging a capacitor,wherein an active discharge circuit is connected in parallel with the capacitor,wherein an interface provides a signal connection between a message-based communication system and the active discharge circuit,wherein the interface comprises at least one input for receiving messages from the message-based communication system,wherein the interface comprises a wake-up functionality,wherein the at least one input comprises an input for the wake-up functionality,wherein the method comprises:receiving at the input for the wake-up functionality a disable discharge command message of said messages for the disabling of the discharge of the capacitor,wherein upon cessation of the disable discharge command message the discharge of the capacitor is enabled.

The capacitor may be included in, or part of, an electrical circuit included in, or part of, or electrically connected to, an electrical device electrically connected to an electrical system. In some embodiments, the at least one input of the interface may comprise a plurality of inputs, i.e. two or more inputs, for receiving messages from the message-based communication system. Thus, the interface may comprise a plurality of inputs for receiving messages from the message-based communication system.

An advantage of the method according to the first aspect is that an interface, which is associated with a message-based communication system and which already has an input for the wake-up functionality, does not need to be equipped with any additional input specifically for the receipt of disable discharge command messages and the control of the active discharge circuit and of the discharge of the capacitor. Further, without the need to add an additional input for the control of the discharge of the capacitor, less cable harness is needed, and consequently, cables and space for cable harness are saved. Thus, the interface and/or the communication system is/are simplified, and the efficiency of the interface and the communication system is improved. Consequently, the efficiency of the discharge functionality is improved.

When many or several electrical devices, each electrical device having a capacitor, are to be connected to an electrical system, even more additional cable harnesses to implement the control of the discharge of all the capacitors would be required in conventional solutions. Thus, in these cases, i.e. when many capacitors are present, the innovative method according to the first aspect further improves the simplification and/or the efficiency of the interface and the communication system, since even less cable harnesses are needed in relation to conventional solutions, and consequently, even more cables and even more space for cable harnesses are saved in relation to conventional solutions. Thus, in these cases, i.e. when many capacitors are present, the efficiency of the discharge of capacitors is further improved by way of the method according to the first aspect.

An advantage of the method according to the first aspect is that less electric power, or electric energy, is consumed by the interface and/or the communication system since there is no need to wake up or activate any electric control unit, ECU, for the control of the active discharge circuit and the control of the discharge of the capacitor, wherein the activation of the electric control unit, ECU, would consume more electric power. Consequently, the efficiency of the interface and the communication system is improved also for this reason, and the efficiency of the discharge functionality is improved.

As defined above, the interface is configured to receive messages from the message-based communication system. However, it is to be understood that the message-based communication system may also be configured to receive messages outputted to the message-based communication system, for example outputted by the interface. The message-based communication system may be referred to as a message-based protocol communication system. It may be defined that the message-based communication system is based on message passing. With regard to communication systems, message passing may be described as a technique where an entity sends a message to a process, for example, and that process selects and runs some appropriate code. Message passing may be described as being different from conventional programming where a process, subroutine, or function is directly invoked by name. Said message may also be referred to as a frame. Thus, the message-based communication system may also be referred to as a frame-based communication system.

An active discharge circuit is a device that actively executes the discharge of the capacitor, for example by way of a resistor and a switch connected in series and then both connected in parallel with the capacitor to be provided with the discharge functionality, wherein the switch is switched to turn on or turn off the discharge of the capacitor. In contrast to the active discharge circuit, there is the passive discharge circuit, which in general includes a resistor (a bleeder resistor), often with a high resistance value, connected in parallel with the capacitor to be provided with the discharge functionality, but without any switch. A passive discharge circuit is constantly discharging the capacitor to a certain degree. In general, an active discharge circuit is more attractive than a passive discharge circuit since the use of an active discharge circuit reduces the losses in the system when the capacitor is in active use.

The wake-up functionality is disclosed in further detail in the detailed described hereinbelow.

According to an advantageous embodiment of the method according to the first aspect, the method comprises:ceasing to receive the disable discharge command message at the input for the wake-up functionality so as to enable the discharge of the capacitor.

An advantage of this embodiment is that the efficiency of the interface and the communication system is further improved. Consequently, the efficiency of the discharge functionality is further improved.

According to a further advantageous embodiment of the method according to the first aspect, the interface comprises an output for signals to the active discharge circuit,wherein the method comprises:in response to the receipt of the disable discharge command message at the input for the wake-up functionality, outputting at the output a disable discharge signal for the disabling of the discharge of the capacitor.

An advantage of this embodiment is that the efficiency of the interface and the communication system is further improved. Consequently, the efficiency of the discharge functionality is further improved.

According to another advantageous embodiment of the method according to the first aspect, the method comprises:in response to the cessation of the disable discharge command message, outputting at the output an enable discharge signal for the enabling of the discharge of the capacitor.

An advantage of this embodiment is that the efficiency of the interface and the communication system is further improved. Consequently, the efficiency of the discharge functionality is further improved.

According to yet another advantageous embodiment of the method according to the first aspect, the method comprises:upon the output of a disable discharge signal from the output, triggering a timer circuit to start timing, whereupon a time period of the timer circuit starts running,during the time period, repeating the disable discharge signal to the active discharge circuit by way of the timer circuit, andon expiry of the time period, ceasing to repeat the disable discharge signal to the active discharge circuit by way of the timer circuit.

An advantage of this embodiment is that the control of the discharge of the capacitor is further improved. Consequently, the efficiency of the discharge functionality is further improved.

According to another advantageous embodiment of the method according to the first aspect, the signal connection between the message-based communication system and the active discharge circuit goes through the timer circuit. An advantage of this embodiment is that the control of the discharge of the capacitor is further improved. Consequently, the efficiency of the discharge functionality is further improved.

According to still another advantageous embodiment of the method according to the first aspect, the method comprises:by way of the waking-up functionality, waking up, or activating, the interface to process the disable discharge command message only, for the disabling and/or enabling of the discharge of the capacitor.

An advantage of this embodiment is that the electric power consumption of the interface and/or the communication system is further reduced. Thus, the efficiency of the interface and the communication system is further improved. Consequently, the efficiency of the discharge functionality is further improved.

According to an advantageous embodiment of the method according to the first aspect, the active discharge circuit comprisesa resistive component, anda discharge switch,wherein the resistive component and the discharge switch are connected in series, andwherein the interface provides a signal connection between the message-based communication system and the discharge switch.

According to a further advantageous embodiment of the method according to the first aspect, the discharge switch comprises a control terminal for selectively closing and opening the discharge switch, wherein the interface provides a signal connection between the message-based communication system and the control terminal of the discharge switch.

According to another advantageous embodiment of the method according to the first aspect, the interface provides a signal connection between the output of the interface and the control terminal of the discharge switch.

According to yet another advantageous embodiment of the method according to the first aspect, the input for the wake-up functionality comprises an input pin. An advantage of this embodiment is that an interface, which is associated with a message-based communication system and which already has an input pin for the wake-up functionality, does not need to be equipped with any additional input pin specifically for the receipt of disable discharge command messages and the control of the active discharge circuit and of the discharge of the capacitor. Without the need to add an additional input pin for the control of the discharge of the capacitor, less cable harness is needed, and consequently, cables and space for cable harness are saved. Thus, the interface and the communication system are simplified, and the efficiency of the interface and the communication system is further improved. Consequently, the efficiency of the discharge functionality is further improved. When many electrical devices, each electrical device having a capacitor, are to be connected to an electrical system, even more additional input pins and even more additional cable harnesses to implement the control of the discharge of all the capacitors would be required in conventional solutions. Thus, in these cases, i.e. when many capacitors are present, this embodiment further improves the simplification and/or the efficiency of the interface and the communication system, since even less cable harnesses are needed in relation to conventional solutions, and consequently, even more cables and even more space for cable harnesses are saved in relation to conventional solutions. Thus, in these cases, i.e. when many capacitors are present, the efficiency of the discharge of capacitors is further improved by way of this embodiment.

According to still another advantageous embodiment of the method according to the first aspect, the output of the interface comprises an output pin.

According to an advantageous embodiment of the method according to the first aspect, the interface comprises a transceiver,wherein the transceiver provides the signal connection between the message-based communication system and the active discharge circuit,wherein the transceiver comprises the at least one input for receiving messages from the message-based communication system, andwherein the transceiver comprises the wake-up functionality.

An advantage of this embodiment is that an efficient implementation of the interface is provided. Consequently, the efficiency of the discharge functionality is further improved.

According to a further advantageous embodiment of the method according to the first aspect, the transceiver comprises the output of the interface.

According to another advantageous embodiment of the method according to the first aspect, the method comprises:by way of the waking-up functionality, waking up, or activating, the transceiver to process the disable discharge command message, for the disabling and/or enabling of the discharge of the capacitor, without waking up, or without activating, any central processing unit, CPU, and/or any electronic control unit, ECU.

An advantage of this embodiment is that the electric power consumption of the interface, which in this embodiment includes the transceiver, and/or the communication system is further reduced. Thus, the efficiency of the interface and the communication system is further improved. Consequently, the efficiency of the discharge functionality is further improved.

According to a further advantageous embodiment of the method according to the first aspect, the transceiver is a controller area network, CAN, transceiver. An advantage of this embodiment is that the efficiency of the interface and the communication system is further improved. Consequently, the efficiency of the discharge functionality is further improved.

However, in alternative embodiments, the transceiver may be a transceiver associated with, or configured to be applied to, any other message-based communication system, for example a local interconnect network, LIN, communication system, or an Ethernet communication system. However, the transceiver may also be configured to be applied to other message-based communication systems.

According to another advantageous embodiment of the method according to the first aspect, the message-based communication system is a vehicle-internal communication system. The innovative control of the discharge functionality is advantageous for vehicles and the message-based communication systems for vehicles, whereby an efficient discharge functionality with regard to the capacitor is provided.

According to still another advantageous embodiment of the method according to the first aspect, the message-based communication system is a controller area network, CAN, protocol communication system. An advantage of this embodiment is that the efficiency of the interface and the communication system is further improved. Consequently, the efficiency of the discharge functionality is further improved. However, in alternative embodiments, the message-based communication system may be any another message-based communication system, for example a local interconnect network, LIN, communication system, or an Ethernet communication system.

According to another advantageous embodiment of the method according to the first aspect, the interface is a controller area network, CAN, interface, and wherein each input of the at least one input is configured to receive controller area network, CAN, protocol messages. An advantage of this embodiment is that the efficiency of the interface and the communication system is further improved. Consequently, the efficiency of the discharge functionality is further improved. However, in alternative embodiments, the interface may be an interface associated with, or configured to be applied to, any other message-based communication system, for example a local interconnect network, LIN, communication system, or an Ethernet communication system. However, the interface may also be configured to be applied to other known message-based communication systems. Correspondingly, in alternative embodiments, each input of the at least one input may be configured to receive any other message according to any other protocol, for example a local interconnect network, LIN, protocol message, or an Ethernet protocol message. Said message may be referred to as a frame. Thus, for example, the controller area network, CAN, protocol message may be referred to as a controller area network, CAN, protocol frame.

According to yet another advantageous embodiment of the method according to the first aspect, the capacitor is included in an electrical circuit, wherein the electrical circuit comprises a direct current link comprising the capacitor. The innovative control of the discharge functionality is advantageous for a direct current link capacitor, whereby an efficient discharge functionality with regard to the capacitor is provided.

According to still another advantageous embodiment of the method according to the first aspect, the capacitor is included in, or part of, an electrical circuit included in, or part of, or electrically connected to, an electrical device electrically connected to an electrical system, wherein the electrical system is electrically connected to one or more electric batteries. The innovative control of the discharge functionality is advantageous for an electrical system provided with one or more electric batteries, whereby an efficient discharge functionality with regard to the capacitor is provided. Each electric battery of the one or more electric battery may be a high voltage electric battery.

According to an advantageous embodiment of the method according to the first aspect, the capacitor is included in, or part of, an electrical circuit included in, or part of, or electrically connected to, an electrical device electrically connected to an electrical system, wherein the electrical system comprises a vehicle electrical system of a vehicle. The innovative control of the discharge functionality is advantageous for vehicles and the electrical systems for vehicles, whereby an efficient discharge functionality with regard to the capacitor is provided.

According to a second aspect of the invention, the above mentioned and other objects are achieved with an apparatus for the discharge of a capacitor, wherein the apparatus comprisesan active discharge circuit connectable in parallel with the capacitor, andan interface for providing a signal connection between a message-based communication system and the active discharge circuit,wherein the interface comprises at least one input for receiving messages from the message-based communication system,wherein the interface comprises a wake-up functionality,wherein the at least one input comprises an input for the wake-up functionality,wherein the interface is configured to receive at the input for the wake-up functionality a disable discharge command message of said messages for the disabling of the discharge of the capacitor, andwherein upon cessation of the disable discharge command message the discharge of the capacitor is enabled.

The capacitor may be included in, or part of, an electrical circuit included in, or part of, or electrically connectable to, an electrical device electrically connectable to an electrical system. As mentioned above, the at least one input of the interface may comprise a plurality of inputs, i.e. two or more inputs, for receiving messages from the message-based communication system.

The advantages of the apparatus according to the second aspect and the advantages of the embodiments of the apparatus according to the second aspect mentioned hereinafter correspond to the above- or below-mentioned advantages of the method according to the first aspect and its embodiments, and are thus not repeated.

According to an advantageous embodiment of the apparatus according to the second aspect, the interface is configured to cease receiving the disable discharge command message at the input for the wake-up functionality so as to enable the discharge of the capacitor.

According to a further advantageous embodiment of the apparatus according to the second aspect, the interface comprises an output, or two or more outputs, for signals to the active discharge circuit,wherein the interface is configured to, in response to the receipt of the disable discharge command message at the input for the wake-up functionality, output at the output, i.e. at the output of the interface, a disable discharge signal for the disabling of the discharge of the capacitor.

According to another advantageous embodiment of the apparatus according to the second aspect, the interface is configured to, in response to the cessation of the disable discharge command message, output at the output, i.e. at the output of the interface, an enable discharge signal for the enabling of the discharge of the capacitor.

According to still another advantageous embodiment of the apparatus according to the second aspect, the apparatus comprises a timer circuit configured to, upon the output of a disable discharge signal from the output, be triggered to start timing, whereupon a time period of the timer circuit starts running,wherein the timer circuit is configured to, during the time period, repeat the disable discharge signal to the active discharge circuit, andwherein the timer circuit is configured to, on expiry of the time period, cease repeating the disable discharge signal to the active discharge circuit.

A timer circuit configured as stated above may be designed in several different ways.

According to yet another advantageous embodiment of the apparatus according to the second aspect, the interface is configured to provide a signal connection between the message-based communication system and the active discharge circuit through the timer circuit.

According to an advantageous embodiment of the apparatus according to the second aspect, the interface is configured to, by way of the waking-up functionality, wake up (or be activated) to process the disable discharge command message only, for the disabling and/or enabling of the discharge of the capacitor.

According to a further advantageous embodiment of the apparatus according to the second aspect, the active discharge circuit comprisesa resistive component, anda discharge switch,wherein the resistive component and the discharge switch are connected in series, andwherein the interface is configured to provide a signal connection between the message-based communication system and the discharge switch.

The resistive component may comprise one or more resistors.

According to another advantageous embodiment of the apparatus according to the second aspect, the discharge switch comprises a control terminal for selectively closing and opening the discharge switch, and wherein the interface is configured to provide a signal connection between the message-based communication system and the control terminal of the discharge switch.

According to yet another advantageous embodiment of the apparatus according to the second aspect, the interface is configured to provide a signal connection between the output of the interface and the control terminal of the discharge switch.

According to still another advantageous embodiment of the apparatus according to the second aspect, the input for the wake-up functionality comprises an input pin.

According to an advantageous embodiment of the apparatus according to the second aspect, the output of the interface comprises an output pin.

According to a further advantageous embodiment of the apparatus according to the second aspect, the interface comprises a transceiver,wherein the transceiver is configured to provide the signal connection between the message-based communication system and the active discharge circuit,wherein the transceiver comprises the at least one input for receiving messages from the message-based communication system, andwherein the transceiver comprises the wake-up functionality.

According to another advantageous embodiment of the apparatus according to the second aspect, the transceiver comprises the output of the interface.

According to still another advantageous embodiment of the apparatus according to the second aspect, the transceiver is configured to, by way of the waking-up functionality, wake up, or be activated, to process the disable discharge command message, for the disabling and/or enabling of the discharge of the capacitor, without waking up, or without activating, any central processing unit, CPU, and/or any electronic control unit, ECU.

According to another advantageous embodiment of the apparatus according to the second aspect, the transceiver is a controller area network, CAN, transceiver.

According to a further advantageous embodiment of the apparatus according to the second aspect, the message-based communication system is a vehicle-internal communication system.

According to still another advantageous embodiment of the apparatus according to the second aspect, the message-based communication system is a controller area network, CAN, protocol communication system.

According to a further advantageous embodiment of the apparatus according to the second aspect, the interface is a controller area network, CAN, interface, wherein each input of the at least one input is configured to receive controller area network, CAN, protocol messages.

According to yet another advantageous embodiment of the apparatus according to the second aspect, the capacitor is included in an electrical circuit, wherein the electrical circuit comprises a direct current link comprising the capacitor.

According to an advantageous embodiment of the apparatus according to the second aspect, the capacitor is included in, or part of, an electrical circuit included in, or part of, or electrically connectable to, an electrical device electrically connectable to an electrical system, wherein the electrical system is electrically connectable to one or more electric batteries, for example one or more battery packs suitable for vehicles. As mentioned above, each electric battery of the one or more electric battery may be a high voltage electric battery.

According to a further advantageous embodiment of the apparatus according to the second aspect, the capacitor is included in, or part of, an electrical circuit included in, or part of, or electrically connectable to, an electrical device electrically connectable to an electrical system, wherein the electrical system comprises a vehicle electrical system of a vehicle. The vehicle electrical system may be configured for direct current. The vehicle electrical system may be a vehicle high voltage system of a vehicle. The vehicle high voltage system may be configured for a voltage above 60 V, for example above 400 V, such as above 650 V. For example, the vehicle high voltage system may be configured for a voltage up to 1500 V.

According to another advantageous embodiment of the apparatus according to the second aspect, the apparatus comprises the capacitor, wherein the active discharge circuit is connected in parallel with the capacitor.

According to still another advantageous embodiment of the apparatus according to the second aspect, the apparatus comprises the message-based communication system, for example the controller area network, CAN, protocol communication system.

According to a third aspect of the invention, the above mentioned and other objects are achieved with vehicle high voltage system comprising one or more apparatuses according to any one of the above- or below-mentioned embodiments.

The vehicle high voltage system may be configured for direct current. The vehicle high voltage system may be configured for a high voltage, such as a voltage above 60 V, for example above 400 V, such as above 650 V. For example, the vehicle high voltage system may be configured for a voltage up to 1500 V. As mentioned above, the vehicle high voltage system may be electrically connectable to one or more electric batteries, for example one or more battery packs suitable for vehicles.

The advantages of the vehicle high voltage system according to the third aspect correspond to the above- or below-mentioned advantages of the apparatus according to the first aspect and its embodiments. The vehicle high voltage system may be, or may be referred to as, a VCB.

According to a fourth aspect of the invention, the above mentioned and other objects are achieved with a vehicle comprising one or more of the group of:an apparatus according to any one of the above- or below-mentioned embodiments; anda vehicle high voltage system according to any one of the above- or below-mentioned embodiments.

The advantages of the vehicle according to the fourth aspect correspond to the above- or below-mentioned advantages of the apparatus according to the first aspect and its embodiments.

The vehicle may be a wheeled vehicle, i.e. a vehicle having wheels. The vehicle may for example be a bus, a tractor vehicle, a heavy vehicle, a truck, or a car. However, other types of vehicles are possible. The vehicle may be referred to as a motor vehicle. The vehicle may be an electric vehicle, EV, for example a hybrid vehicle or a hybrid electric vehicle, HEV, or a battery electric vehicle, BEV.

The above-mentioned features and embodiments of the method, the apparatus, the vehicle high voltage system and the vehicle, respectively, may be combined in various possible ways providing further advantageous embodiments.

Further advantageous embodiments of the method, the apparatus, the vehicle high voltage system and the vehicle according to the present invention and further advantages with the embodiments of the present invention emerge from the detailed description of embodiments.

DETAILED DESCRIPTION

With reference toFIG.1, a vehicle100is schematically illustrated. The vehicle100may be called a motor vehicle100. In embodiments, the vehicle100may, for example, be a car, a bus, a tractor vehicle, a truck, for example a heavy truck, for example provided with a trailer. Other types of vehicles are possible.

With reference toFIG.1, the vehicle100comprises a powertrain102, which in the shown embodiment comprises a combustion engine104, for example an internal combustion engine or another combustion engine, which in a conventional manner, via a first output shaft106and usually via a flywheel, may be connected to a gearbox108via a clutch110. In general, the combustion engine104comprises cylinders.

In addition to the powertrain102comprising a combustion engine104, the vehicle100may include one or more electric motors111, or electrical machines, for driving drive wheels114,116,118,120of the vehicle100and may thus, for example, be a so-called hybrid vehicle. The electric motor111, or electrical machine, may be provided with electric power from an electrical energy unit121, which may be included in the vehicle100. The electrical energy unit121may include an electric battery unit123or a plurality of electric battery units123, which also may be referred to as electric battery packs. The battery unit123may include one or more electric batteries125. Thus, the electric battery125may be configured to power, i.e. to provide electric power to, the electrical motor111. It is to be understood that each of the electric battery125may comprises a plurality of electric battery cells. Electric batteries125, electric battery packs and electric battery cells are known to the skilled person and thus not described in further detail.

However, instead of the powertrain102comprising a combustion engine104, the vehicle100may include only an electric motor111, or only electric motors111, for driving the drive wheels114,116,118,120of the vehicle100, i.e. excluding the combustion engine104, whereby the vehicle100may be a pure electrical vehicle. Thus, according to embodiments, the vehicle100may be an electric vehicle, EV, for example a hybrid vehicle or a hybrid electric vehicle, HEV, or a battery electric vehicle, BEV.

With reference toFIG.1, the combustion engine104is controlled by the engine's control system via a control device112. Likewise, the clutch110and the gearbox108may be controlled by the engine's control system, with the help of one or more control devices (not shown). The control device112and/or another control device may thus be configured to control the combustion engine104, the clutch110, the gearbox108, and/or any other units/devices/entities of the vehicle100. However, inFIG.1, only a small selection of the units/devices/entities of the vehicle100is illustrated.

Naturally, the powertrain102of the vehicle100may be of a different type, such as a type with a conventional automatic gearbox, a type with a hybrid driveline, or a type with a driveline for a pure electrical vehicle, etc. As mentioned above, the powertrain102may include one or more electric motors111, or electrical machines, for driving the drive wheels114,116,118,120of the vehicle100, implementing a so-called hybrid drive. In the shown embodiment, the vehicle100comprises four wheels114,116,118,120, but may have more wheels. The electric motor111, or electrical machine, may be arranged essentially anywhere, as long as torque is provided to one or more of the wheels114,116,118,120, for example adjacent to one or more of the wheels114,116,118,120, or along a propeller shaft122of the vehicle100, for example between the gearbox108and the clutch110, as is understood by a skilled person.

With reference toFIG.1, the vehicle100may comprise a propeller shaft122from the gearbox108which drives two of the wheels114,116via a central gear124, for example a conventional differential, and two drive shafts126,128of the vehicle100. The two drive shafts126,128are connected to the central gear124. The vehicle100may comprise a fuel tank129coupled to the combustion engine104, and the combustion engine104may be provided with fuel from the fuel tank129.

With reference toFIG.1, the vehicle100may comprise an exhaust gas after-treatment system130for treatment/purification of an exhaust gas/emissions of an exhaust gas stream132(indicated with arrows) from the combustion engine104. The exhaust gas/emissions is/are the result of the combustion in the combustion chamber of the combustion engine104. The exhaust gas after-treatment system130may also be called an exhaust gas purification system.

With reference toFIG.1, the vehicle100may include one or more electrical systems134, for example a vehicle electrical system136, electrically connectable to one or more electric batteries125. The electrical system134or the vehicle electrical system136may be configured to electrically connect the electric battery125to the electric motor111. The vehicle electrical system136may be, or referred to as, a vehicle high voltage system (VCB)136. The electrical system134may be configured for direct current, DC. Thus, the vehicle electrical system136may be configured for direct current.

Thus, vehicle high voltage system136may be electrically connected or coupled, or connectable, to one or more electric batteries125and/or one or more electric battery packs of the vehicle100. The electric power, or the electric current, for example the direct current, of the vehicle high voltage system136is transferred at a high voltage, for example above 60 V, such as above 400 V, or above 650 V. The electric power, or the electric current, of the vehicle high voltage system136may be transferred at a voltage up to 1500 V. Thus, the vehicle high voltage system136may be configured for a high voltage, such as a voltage above 60 V, for example above 400 V, or above 650 V. For example, the vehicle high voltage system136may be configured for a voltage up to 1500 V.

With reference toFIG.1, the electric battery125may be electrically connected or coupled to the electric motor111via an inverter138in ways known to the skilled person. The inverter138, for example called power inverter138, may be referred to as an electrical device140. In embodiments, the inverter138may be integrated into the electric motor111or be external thereto. Thus, the electrical device140or the inverter138may be electrically connectable, or connected or coupled, to the electrical system134or the vehicle electrical system136. The electrical device140, for example the inverter138, may comprise or be electrically connected, or connectable, to an electrical circuit142, which may comprise a capacitor150(seeFIGS.2and4), for example provided to act, or function, as an electrical buffer. In the shown embodiment, the electrical circuit142may be called a direct current link142. Expressed alternatively, the electrical circuit142may comprise a direct current link142comprising the capacitor150. In the shown embodiment, the capacitor150may be called a direct current link capacitor. Further, an active discharge circuit144may be provided. The active discharge circuit144may be connectable, or connected, in parallel with the capacitor150(seeFIG.2) in order to discharge the capacitor150at a certain occasion or at certain occasions. For example, it may be desirable to have the capacitor150discharged when the vehicle100is turned off and parked to hinder that users or personal may come into contact with a charged capacitor, to prevent a possible fire, and/or to avoid heating.

With reference toFIG.1, the vehicle100may be provided with at least one electronic control unit, ECU,146. In general, the vehicle100may be provided with a plurality of electronic control units, ECUs. Each electronic control unit, ECU,146may be configured to control a part or various parts, for example one or more electrical devices, of the vehicle100, for example the electric battery unit123holding one or more electric batteries125. The electric battery unit123may be referred to as a direct current, DC, power source. The electronic control unit, ECU,146may be connected to the electrical device140or devices140, for example the electric battery unit123, which the electronic control unit, ECU,146is configured to control, via a message-based communication system148. Thus, the electronic control unit, ECU,146may communicate with the electrical devices140via the message-based communication system148.

With reference toFIG.2, it is schematically illustrated how one or more electric batteries125are electrically connected to an electric motor111, for example an electric motor111of a vehicle100. The electric battery125is connected to the electric motor111via a power inverter138. An electrical circuit142, which comprises a capacitor150, is electrically connected, or connectable, or included in the power inverter138, which may be referred to as an electrical device140. In other embodiments, the electrical device140may be, or comprise, some other component or device instead of a power inverter138.

With reference toFIG.2, in the shown embodiment, the electrical circuit142may be referred to as a direct current link. In the shown embodiment, the capacitor150may be referred to as a direct current link capacitor. In the shown embodiment, the capacitor150is located between the electric battery unit123holding the electric batteries125and the power inverter138. In the shown embodiment, the purpose of the capacitor150may be to provide a more stable direct current, DC, voltage, for example minimizing voltage dips as the power inverter138sporadically demands heavy current. Provided is also an active discharge circuit144, which may correspond to the active discharge circuit202and302disclosed in further detail herein below. As shown inFIG.2, the active discharge circuit144is connected, or connectable, in parallel with the capacitor150. The configuration schematically illustrated inFIG.2, which connects the electric battery125to the electric motor111, may be referred to as an electrical system134or a vehicle electrical system136. In other embodiments, the electrical system134may have other configurations. For example, the electrical system134or the vehicle electrical system136may comprise less or more items, or elements, than what is illustrated inFIG.2.

With reference toFIG.3, a first embodiment of the apparatus200for the discharge of a capacitor, for example the capacitor150shown inFIG.2, according to the second aspect is schematically illustrated. The capacitor150may be included in an electrical circuit142included in, or electrically connectable to, an electrical device140electrically connectable to an electrical system134,136. The apparatus200includes an active discharge circuit202connectable in parallel with the capacitor150. More specifically, it may be defined that the active discharge circuit202is electrically connectable in parallel with the capacitor150. The active discharge circuit202may be connectable in parallel with the capacitor150via position A and position B indicated inFIG.3. Thus, when the active discharge circuit202is connected or coupled to the capacitor150, the capacitor150is positioned between the position A and position B and is connected to position A and position B, wherein the position A may represent a plus or positive (+) position and the position B may represent a minus or negative (−) position of the apparatus200.

With reference toFIG.3, the active discharge circuit202may include a resistive component204and a discharge switch206. The resistive component204and the discharge switch206are connected in series with one another. More specifically, it may be defined that the resistive component204and the discharge switch206are electrically connected in series. The resistive component204may comprise one or more resistors208. The discharge switch206may comprise any one of a MOSFET switch and an IGBT switch. However, other types of switches for the discharge switch206are possible.

With reference toFIG.3, the apparatus200further includes an interface210for providing a signal connection211between a message-based communication system212and the active discharge circuit202. For example, the message-based communication system212may correspond to the message-based communication system148schematically illustrated inFIG.1. However, other configurations of the message-based communication system212are possible. The message-based communication system212may be connectable to one or more electric control units, ECUs, for example included in a vehicle100, for example as illustrated inFIG.1. It may be defined that the interface210is configured to be connected or coupled, directly or indirectly, to the active discharge circuit202. It may be defined that the interface210is configured to, directly or indirectly, communicate with the active discharge circuit202. More specifically, the interface210may be configured to provide a signal connection211between the message-based communication system212and the discharge switch206of the active discharge circuit202.

With reference toFIG.5, which in a more detailed view schematically illustrates an embodiment of the interface210. The interface210comprises at least one input214,216,218,220,222, for example a plurality of inputs214,216,218,220,222, i.e. two or more inputs214,216,218,220,222, for receiving messages from the message-based communication system212. Thus, in some embodiments, the at least one input214,216,218,220,222may comprise a plurality of inputs214,216,218,220,222for receiving messages from the message-based communication system. The interface210comprises a wake-up functionality224, or wake-up function, which is disclosed in further detail hereinbelow. The wake-up functionality224may include, or be referred to as, a selective wake-up functionality. The at least one input214,216,218,220,222, for example the plurality of inputs214,216,218,220,222, of the interface210includes an input218for the wake-up functionality224. In addition to the wake-up functionality224, the interface210may include additional functionalities.

With reference toFIGS.3and5, the interface210is configured to receive at the input218for the wake-up functionality224a disable discharge command message of said messages, i.e. the messages from the message-based communication system212, for the disabling of the discharge of the capacitor150. Upon cessation of the disable discharge command message, the discharge of the capacitor150is enabled. Expressed alternatively, the cessation of the disable discharge command message enables the discharge of the capacitor150. Thus, as long as a disable discharge command message is received at the at the input218for the wake-up functionality224, the discharge of the capacitor150is blocked, inactivated or disabled, and when the disable discharge command message is no longer received by the interface210, the discharge of the capacitor150is enabled or activated.

With reference toFIGS.3and5, the interface210may be configured to cease receiving the disable discharge command message at the input218for the wake-up functionality224so as to enable the discharge of the capacitor150. The interface210may include an output226for signals to the active discharge circuit202, for example, more specifically to the discharge switch206. In addition to the output226for signals to the active discharge circuit202, the interface210may comprise additional outputs220,222,228for the output of signals or messages, for example to the message-based communication system212. Thus, the interface210may comprise a plurality of outputs220,222,226,228, i.e. two or more outputs220,222,226,228.

With reference toFIGS.3and5, the interface210may be configured to, in response to the receipt of the disable discharge command message at the input218for the wake-up functionality224, output at the output226, i.e. at the output226for signals to the active discharge circuit202, a disable discharge signal for the disabling of the discharge of the capacitor150, or for the blocking of the discharge of the capacitor150. Expressed alternatively, the interface210may be configured to, in response to the receipt of the disable discharge command message at the input218for the wake-up functionality224, send a disable discharge signal for the disabling of the discharge of the capacitor150from the output226, i.e. from the output226for signals to the active discharge circuit202, to the active discharge circuit202, for example, more specifically to the discharge switch206. Further, the interface210may be configured to, in response to the cessation of the disable discharge command message, output at the output226, i.e. at the output226for signals to the active discharge circuit202, an enable discharge signal for the enabling of the discharge of the capacitor150.

With reference toFIG.3, the discharge switch206may comprise a control terminal230for selectively closing and opening the discharge switch206, or for selectively turning the discharge switch206on and off, wherein the interface210may be configured to provide a signal connection211between the message-based communication system212and the control terminal230of the discharge switch206. The interface210may be configured to provide a signal connection211between the output226, i.e. the output226for signals to the active discharge circuit202, of the interface210and the control terminal230of the discharge switch206.

With reference toFIG.3, it may be defined that the discharge switch206is electrically operable. It may be defined that the discharge switch206is switchable between an open position and a closed position, or operable between an off-state or on-state. InFIG.3, the discharge switch206is illustrated in the open position while the closed positions of the discharge switch206is illustrated by a dotted line inFIG.3. With reference toFIG.3, more specifically, it may be defined that the interface210is configured to perform a logical inversion of the disable discharge command message received from the message-based communication system212, for example disclosed as follows: When the disable discharge command message has a high logic level, the disable discharge signal outputted from the interface210, for example from the output226, i.e. the output226for signals to the active discharge circuit202, to the control terminal230of the discharge switch206has a low voltage level so that the discharge switch206is in the open position, i.e. the discharge of the capacitor150is disabled, i.e. the capacitor150is not discharged. It may be defined that the output226for signals to the active discharge circuit202is connected to the active discharge circuit202, more specifically to the discharge switch206, or even more specifically to the control terminal230of the discharge switch206. It may be defined that when the disable discharge command message has a high logic level, the output226, i.e. the output226for signals to the active discharge circuit202, has a low voltage level so that the discharge switch206is in the open position. When the disable discharge command message from the message-based communication system212ceases, i.e. drops to a low logic level, the enable discharge signal outputted from the interface210, for example from the output226, i.e. the output226for signals to the active discharge circuit202, to the control terminal230of the discharge switch206has a high voltage level, i.e. a voltage sufficient, to switch the discharge switch206to the closed position, i.e. the discharge of the capacitor150is enabled, i.e. the capacitor150is discharged. It may be defined that when the disable discharge command message has a low logic level, the output226, i.e. the output226for signals to the active discharge circuit202, has a high voltage level, i.e. voltage sufficiently high, to switch the discharge switch206to the closed position.

It may be defined that when the discharge switch206is in the closed position, the discharge switch206is configured to conduct an electric current or allow an electric current to pass. It may be defined that when the discharge switch206is in the open position, the discharge switch206is configured to interrupt an electric current or an electric current path therethrough.

With reference toFIGS.3and5, the interface210may be configured to, by way of the waking-up functionality224, wake up (or be activated) to process the disable discharge command message (received from the message-based communication system212) only, for the disabling and/or enabling of the discharge of the capacitor150, for example without waking up (without activating) any central processing unit, CPU, and/or any electronic control unit, ECU.

With reference toFIG.5, the input218for the wake-up functionality224may comprise an input pin232. Further, each of the other inputs214,216,220,222of the plurality of inputs214,216,218,220,222may comprise an input pin234,236,238,240. The output226of the interface210, i.e. the output226for signals to the active discharge circuit202, may comprise an output pin242. The output226for signals to the active discharge circuit202, which may comprise an output pin242, may be referred to as an inhibit output or inhibit output pin. Further, each of the additional outputs220,222,228may comprise an output pin238,240,244.

With reference toFIGS.3and5, the interface210may comprise a transceiver246. The transceiver246may thus be configured to provide the signal connection211between the message-based communication system212and the active discharge circuit202, for example, more specifically between the message-based communication system212and the discharge switch206, or even more specifically between the message-based communication system212and the control terminal230of the discharge switch206.

When the interface210comprises the transceiver246, the transceiver246comprises the at least one input214,216,218,220,222, for example the plurality of inputs214,216,218,220,222, for receiving messages from the message-based communication system212. When the interface210comprises the transceiver246, the transceiver246comprises the wake-up functionality224. When the interface210comprises the transceiver246, the transceiver246may comprise the output226of the interface210, i.e. the output226for signals to the active discharge circuit202. When the interface210comprises the transceiver246, the transceiver246may be configured to, by way of the waking-up functionality224, wake up (or be activated) to process the disable discharge command message received from the message-based communication system212, for the disabling and/or enabling of the discharge of the capacitor150, without waking up any central processing unit, CPU, and/or any electronic control unit, ECU.

With reference toFIGS.1and3, the message-based communication system212may be a vehicle-internal communication system148.

With reference toFIG.4, a second embodiment of the apparatus300for the discharge of a capacitor, for example the capacitor150shown inFIG.2or the capacitor350included in electrical circuit342present inFIG.4, according to the second aspect is schematically illustrated. The second embodiment of the apparatus300shown inFIG.4corresponds in several aspects to the first embodiment of the apparatus200shown inFIG.3, so only some of the differences between the second embodiment and the first embodiment will be mentioned herein in detail.

However, with reference toFIG.4, as for the first embodiment of the apparatus200according to second first aspect, the second embodiment of the apparatus300ofFIG.4also, in a corresponding manner, includes an active discharge circuit302, which may include a resistive component304and a discharge switch306. The active discharge circuit302may be connectable in parallel with the capacitor350via position A and position B indicated inFIG.4. Thus, when the active discharge circuit302is connected or coupled to the capacitor350, the capacitor350is positioned between position A and position B and is connected to the position A and the position B of the apparatus300. The resistive component304may comprise one or more resistors308. In a corresponding way, the apparatus300includes an interface310for providing a signal connection311between the message-based communication system212and the active discharge circuit302. The interface310may essentially correspond to the interface210illustrated inFIG.5. In corresponding way, the discharge switch306may comprise a control terminal330for selectively closing and opening the discharge switch306.

With reference toFIG.4, the apparatus300may include a timer circuit352configured to, upon the output of a disable discharge signal from the output226(i.e. the output226for signals to the active discharge circuit302), be triggered to start timing, whereupon a time period of the timer circuit352starts running. The timer circuit352is configured to, during the time period, repeat the disable discharge signal to the active discharge circuit302. The timer circuit352is configured to, on expiry of the time period, cease repeating the disable discharge signal to the active discharge circuit302. The interface310may be configured to provide a signal connection311between the message-based communication system212and the active discharge circuit302through, or via, the timer circuit352. It may be defined that the signal connection311between the message-based communication system212and the active discharge circuit302comprises the timer circuit352. Thus, it may be defined that the output226for signals to the active discharge circuit302is connected to timer circuit352, and that the timer circuit352is connected to the active discharge circuit302, more specifically to the discharge switch306, or even more specifically to the control terminal330of the discharge switch306. A timer circuit352per se, which includes the above-mentioned features, may be designed in several different ways.

With reference toFIG.4, the apparatus300may include a central processing unit, CPU,354, which based on messages from the message-based communication system212and received by the interface310is configured to process the messages and output control signals for controlling various different electrical units or devises. The central processing unit, CPU,354is not necessary for the applications of the disclosed innovative embodiments of the apparatus200,300according to the second aspect. The first embodiment of the apparatus200illustrated inFIG.3may also be provided with such a central processing unit, CPU. In embodiments of the apparatus according to the second aspect, the central processing unit, CPU,354schematically illustrated inFIG.4may be excluded while the timer circuit352may be maintained.

With reference toFIGS.3and4, according to some embodiments, each of the apparatuses200,300may include the capacitor150,350, wherein the active discharge circuit202,302may be connected in parallel with the capacitor150,350. Further, according to some embodiments, each of the apparatuses200,300may include the message-based communication system212.

With reference toFIGS.1,3and4, the message-based communication system148,212may be referred to as a message-based protocol communication system. It may be defined that the message-based communication system148,212is based on message passing. As mentioned above, with regard to communication systems, message passing may be described as a technique where an entity sends a message to a process, for example, and that process selects and runs some appropriate code. Message passing may be described as being different from conventional programming where instead a process, subroutine, or function is directly invoked by name. Said message may also be referred to as a frame. Thus, the message-based communication system may be referred to as a frame-based communication system.

The message-based communication system148,212may be a controller area network, CAN, protocol communication system. However, in alternative embodiments, the message-based communication system148,212may be another message-based communication system, for example a local interconnect network, LIN, communication system, or an Ethernet communication system.

With reference toFIGS.1and3to5, the interface210,310may be a controller area network, CAN, interface, wherein each input214,216,218,220,222of the at least one input214,216,218,220,222, for example of the plurality of inputs214,216,218,220,222, is configured to receive controller area network, CAN, protocol messages. However, in alternative embodiments, the interface210,310may be an interface associated with, or configured to be applied to, any other message-based communication system, for example a local interconnect network, LIN, communication system, or an Ethernet communication system. However, the interface210,310may also be configured to be applied to other message-based communication systems. Correspondingly, in alternative embodiments, each input214,216,218,220,222of the at least one input214,216,218,220,222, for example of the plurality of inputs214,216,218,220,222, of the interface210,310may be configured to receive any other message according to any other protocol, for example a local interconnect network, LIN, protocol message, or a Ethernet protocol message. For example, the controller area network, CAN, protocol message may be referred to as a controller area network, CAN, protocol frame.

With reference toFIGS.3to5, the transceiver246,346may be a controller area network, CAN, transceiver. However, in alternative embodiments, the transceiver246,346may be a transceiver associated with, or configured to be applied to, any other message-based communication system, for example a local interconnect network, LIN, communication system, or an Ethernet communication system. However, the transceiver246,236may also be configured to be applied to other message-based communication systems.

With regard to controller area network, CAN, the controller area network, CAN, interface may be referred to as a controller area network, CAN, protocol interface. The controller area network, CAN, interface may comprise, or be referred to as, a controller area network, CAN, circuit. The controller area network, CAN, circuit may comprise the transceiver.

With regard to controller area network, CAN, the controller area network, CAN, communication system may be described as being based on and/or configured to use or apply the controller area network, CAN, protocol. The controller area network, CAN, protocol communication system may be referred to as a controller area network, CAN, communication system. The controller area network, CAN, protocol communication system may include, or be referred to as, a controller area network, CAN, bus.

With regard to controller area network, CAN, the message from the controller area network, CAN, protocol communication system may be referred to as a controller area network, CAN, protocol message. The controller area network, CAN, protocol message may be referred to as a controller area network, CAN, message or a controller area network, CAN, frame.

With regard to controller area network, CAN, the controller area network, CAN, transceiver may be referred to as a controller area network, CAN, protocol transceiver.

When controller area network, CAN, is present, the wake-up functionality224or function, or capability, or mechanism may be referred to as a CAN wake-up functionality, for example selective CAN wake-up functionality. For example, this functionality may be a feature present in some CAN transceivers, and one original use of such a functionality is intended for the waking up a unit, for example an ECU, via a CAN message, hence wake up on CAN. For a version of a wake-up functionality224, or function, reference is made to ISO 11898-2:2016, which inter alia discloses further details about the wake-up functionality224for CAN.

With reference toFIG.6, aspects of embodiments of the method for discharging a capacitor150,350, for example a capacitor150,350as disclosed above, are schematically illustrated, wherein an active discharge circuit202,302is connected in parallel with the capacitor150,350, wherein an interface210,310provides a signal connection211,311between a message-based communication system148,212and the active discharge circuit210,310, wherein the interface210,310comprises at least one input214,216,218,220,222for receiving messages from the message-based communication system148,212, wherein the interface210,310comprises a wake-up functionality224, and wherein the at least one input214,216,218,220,222comprises an input218for the wake-up functionality.

Embodiments of the method may include:receiving401at the input218for the wake-up functionality224a disable discharge command message of said messages for the disabling of the discharge of the capacitor150,350(wherein upon cessation of the disable discharge command message the discharge of the capacitor150,350is enabled);by way of the waking-up functionality, waking up402, or activating, the interface201,310to process the disable discharge command message only, for the disabling and/or enabling of the discharge of the capacitor150,350;in response to the receipt401of the disable discharge command message at the input218for the wake-up functionality224, outputting403at the output226a disable discharge signal for the disabling of the discharge of the capacitor150,350;ceasing404to receive the disable discharge command message at the input218for the wake-up functionality224so as to enable the discharge of the capacitor150,350;in response to the cessation404of the disable discharge command message, outputting405at the output226an enable discharge signal for the enabling of the discharge of the capacitor150,350.

When a timer circuit352is provided, the method may additionally include:upon the output403of a disable discharge signal from the output, triggering406the timer circuit352to start timing, whereupon a time period of the timer circuit352starts running,during the time period, repeating407the disable discharge signal to the active discharge circuit302by way of the timer circuit352, andon expiry of the time period, ceasing408to repeat the disable discharge signal to the active discharge circuit302by way of the timer circuit352.

The dotted arrows inFIG.6illustrate embodiments of the method including the additional steps406,407and408.

Further, when a transceiver246,346is provided, the method may include:

by way of the waking-up functionality224, waking up, or activating, the transceiver246,346to process the disable discharge command message, for the disabling and/or enabling of the discharge of the capacitor150,350, without waking up any central processing unit, CPU, and/or any electronic control unit, ECU.

Unless disclosed otherwise, it should be noted that the method steps illustrated inFIG.6and described herein do not necessarily have to be executed in the order illustrated inFIG.6. The steps may essentially be executed in any suitable order. Further, one or more steps may be excluded or added without departing from the scope of the appended claims.

With reference toFIGS.1,3and4, an embodiment of the vehicle high voltage system136according to the third aspect of the invention is also schematically illustrated. The vehicle high voltage system136may comprise any one of the embodiments of the apparatus200,300disclosed above or below. However, with reference toFIG.2, the electrical circuit142and the capacitor150may be located at other locations in the vehicle100, or outside any vehicle100and may be included in, or electrically connectable to, any other electrical device different from the electrical device140disclosed above, for example an alternating current, AC, compressor, a heater for heating one or more regions in the vehicle100, a power inverter different from the power inverter138disclosed above, a DC-to-DC converter, a pump, a power take-off unit of any kind etc.

With reference toFIG.1, an embodiment of the vehicle100according to the fourth aspect of the invention is schematically illustrated. The vehicle100comprises one or more of the group of: an apparatus200,300according to any one of the above- or below-mentioned embodiments; and a vehicle high voltage system136according to any one of the above- or below-mentioned embodiments.

It is to be understood that other applications of the embodiments of the apparatus200,300according to the second aspect and embodiments of the method according to the first aspect, in addition to an application to a vehicle100and any other application mentioned above, are possible. It is to be understood that embodiments of the apparatus200,300according to the second aspect and embodiments of the method according to the first aspect may be applied to more than one capacitor.

The present invention is not limited to the above described embodiments. Instead, the present invention relates to, and encompasses all different embodiments being included within the scope of the independent claims.