Patent Description:
The use of contactor devices for connecting and disconnecting electronic circuits in a power supply system is known state of the art. With the advanced development of electric vehicles (EV) or hybrid electric vehicles (HEV), high voltage (HV) power supply systems become more and more common in vehicles. As such high voltage systems nowadays are capable of supplying voltages in a typical range between <NUM> V and <NUM> kV and may be even capable of supplying higher voltages in future applications, these high voltage power supply systems present a greater shock hazard than traditional powertrains. Accordingly, the prevention of safety hazards and overcurrent protection is of utmost importance for these systems. For example, it is important to ensure the safety of the vehicle's passengers, of roadside assistance or of maintenance workers, in cases of malfunctions of the high voltage power supply system or of an accident of the vehicle, which affects the electronic circuits of the power supply system.

Accordingly, the safety requirements for a power supply system and for contactor devices used to control current flow in the power supply system are increasing, especially where the power supply system is used for storing energy to drive a vehicle. <FIG> shows a typical setup of a power supply system <NUM>, which is for example used in an electrified vehicle.

For providing high voltage in the range between <NUM> V and at least <NUM> kV to a motor of the EV or HEV vehicle in a driving state, a plurality of batteries modules (or battery packs) are electrically connected to form a high voltage battery <NUM>. Each battery pack usually comprises a plurality of battery cells, which are electrically connected in series and/or in parallel. Hereby, for example, around <NUM> to <NUM> battery cells may be electrically connected to form a single high voltage battery pack.

In case that the operation conditions in the power supply system become unsafe, for example due to overcurrent or malfunctions occurring in the electronic circuits of the power supply system or because a vehicle, which is driven by the power stored in the power supply system, has an accident, the current flow in the power supply system should be interruptible immediately and permanently. For this purpose, it is known to connect an additional overcurrent protection device <NUM> in series to the high voltage battery <NUM>. One example for such an overcurrent protection device <NUM> is a fuse, which uses a metal wire or a strip that melts, when overcurrent occurs. Recently, also the use of pyroelectric devices, also known as pyrofuses, which are activated by triggering a pyroelectric charge for severing a busbar being mounted in the supply line of the power supply system, has been established as overcurrent protection devices <NUM>. Overcurrent protection devices <NUM> can be located at the positive terminal of the battery <NUM>, at the negative terminal of the battery <NUM>, within the battery <NUM> or in several locations of the HV power supply system <NUM>.

In order to connect and disconnect the battery <NUM> on the positive terminal and on the negative terminal to a DC bus that connects the battery to external loads (or to a charger), a positive main contactor <NUM> and a negative main contactor <NUM> are electrically connected in series with the terminals of the battery <NUM>. External loads may include high voltage components, like motor inverters (DCAC converters), DCDC converters, or chargers (ACDC converters), heaters, auxiliary loads or other high voltage components. Conventional contactor devices are capable of reversibly changing a state between a closed state, where current flow through the contactor device is possible and an open state, where current flow through the contactor device is prevented, usually by moving at least one moveable contact.

In order to measure a battery current provided by the battery, the power supply system <NUM> usually also comprises one or more current sensors, often in form of a dedicated shunt resistor <NUM>, which is electrically connected in series with the HV battery <NUM>. The power supply system <NUM> contains electronics to measure a voltage drop across the shunt resistor <NUM>. Typically, these electronics are part of a battery management system (BMS, not shown), which monitors the operation of the power supply system <NUM>. The battery management system also often controls the actuation of the positive main contactor <NUM> and the negative main contactor <NUM>, and controls and diagnoses the functioning of the fuse or pyro fuse <NUM>.

Accordingly, in conventional power supply systems, various individual components need to be interconnected in the HV power supply system, for example, when assembling the HV battery power supply system <NUM>, or a sub-assembly of the HV battery, e.g. a HV battery junction box or a HV battery disconnection unit or a HV battery power distribution unit. For connecting the individual components of the power supply system <NUM>, typically copper or aluminium busbars are used. The interfaces between the individual components are mostly bolted or accomplished by connectors. In rare cases also welding may be applied, when the individual components provide weld interfaces, but bolt interfaces. Accordingly, depending on the type of interconnection, the interfaces between battery <NUM> and fuse <NUM>, between fuse <NUM> and positive main contactor <NUM>, between battery <NUM> and shunt current sensor <NUM> and the interface between shunt current sensor <NUM> and negative main contactor <NUM> all introduce an additional ohmic resistance into a main battery current path. Depending on the interconnection technology, these interfaces may become a large source of energy loss and unintended heat generation. Especially in high power applications, such as fast charging, this issue becomes a system level limitation, which limits the charging currents applicable in the power supply system and can prolong the charging duration. Furthermore, it is necessary that the BMS of the power supply system <NUM> needs dedicated control and monitoring functions for each of the components comprises in the power supply system <NUM>, so that the structure of the BMS can become complicated.

For example, <CIT> discloses a contactor device, which comprises at least one fixed contact, at least one moveable contact, and at least one first actuator, which is configured to reversibly move the at least one moveable contact between the open position and the closed position. The contactor device further comprises at least one second actuator, which is configured to move the at least one fixed contact into a fired position, wherein in the fired position, the at least one fixed contact is permanently disconnected from the at least one moveable contact.

<CIT> discloses a fuse assembly, which includes a pair of connectors and formed of an electrically conductive material to allow the fuse assembly to be electrically connected into an electric vehicle drive system. A fusible link, which reacts to current flowing through the fuse assembly in excess of a predetermined current, is electrically connected between the connectors. A current sensing element, which includes a shunt resistor, is also electrically connected between the connectors.

In this respect, the inventors of the present invention have recognized that there is still a need for a contactor device, which can provide a higher integration of functionalities and/or can lower the interconnections necessary in a power supply system. Accordingly, it is an object of the present invention to provide an improved contactor device for high voltage applications, a high voltage energy storage system comprising the contactor device and a corresponding method for controlling the contactor device, which can provide a higher level of functional integration and/or can lower the necessary interconnections and the associated interconnection resistances in a power supply system. Furthermore, it is an object of the present invention to provide a space- and weight-saving and economic solution.

At least one of these objects is solved by the subject matter of the independent claims. Advantageous aspects of the present disclosure are the subject matter of the dependent claims.

In particular, the present disclosure provides a contactor device, which comprises a contact arrangement, which includes at least one moveable bus bar and at least one fixed bus bar, wherein the at least one moveable bus bar has a first contact region and the at least one fixed bus bar has a second contact region, and at least one actuation element, which is configured to change a state of the contactor device at least to and from an open state, and to and from a closed state, wherein in the open state the first contact region is electrically isolated from the second contact region, and in the closed state the first contact region is conductively coupled to the second contact region. The contact arrangement comprises a first current sensing element with a first predetermined resistance, wherein the first current sensing element is integrally formed with one of the bus bars included in the contact arrangement.

By integrating a current sensing element into the contactor device, the need for providing an external shunt resistor in a HV power supply system can be dispensed, so that the number of necessary interconnections in the HV power supply system can be reduced. This allows a quicker and more cost efficient assembly of the HV power supply system or a battery pack. By integrally forming the current sensing element as a shunt resistor with one of the bus bars of the contactor device, the two components can be merged into a single component or can be fabricated as a single component. Accordingly, the energy loss and unintended heat generation at interconnection interfaces of the HV power supply system can be decreased. Here, the term "integrally formed" should explicitly include that two components, which are integrally formed, cannot be separated from each other without destroying at least one of the two components.

According to a second example, the contactor device may comprise a contactor housing, which at least partially houses the first bus bar and the second bus bar, wherein the first current sensing element is arranged within the contactor housing. In an optional implementation, the contactor housing is a hermetically sealed housing, which further helps in suppressing the formation of arcs, since the sealed housing may be filled with a vacuum and/or an electronegative gas.

According to a third example, each of the at least one moveable bus bars comprises a deflectable contact region, which is capable of elastically deflecting between an open position, in which each of the at least one moveable bus bars is electrically isolated from each of the at least one fixed bus bar, and a second position, in which each of the at least one moveable bus bars is conductively coupled to respectively one of the at least one fixed bus bar. In this manner a transition force provided by the at least one actuation element for changing the state of the contactor device can be transmitted effectively, since it is not necessary to move the second bus bars as a whole. In an alternative implementation, however, the moveable bus bars may be moved as a whole between the first position and the second position.

According to a fourth example, the first current sensing element and the one bus bar of the contact arrangement, with which the first current sensing element is integrally formed, are formed of a same conductive material. This configuration may simplify the fabrication of the integrated first current sensing element, since it is possible to directly fabricate the respective bus bar with the current sensing element in one piece. Accordingly, it is also possible to further reduce the resistance of the interconnection interfaces, since no additional interface resistance needs to be introduced. Alternatively, the first current sensing element and the one bus bar may be formed from different conductive materials and the first current sensing element may be interconnected with the one bus bar by welding, soldering, brazing or any other suitable interconnection method, which introduces only a small interface resistance.

According to a fifth example, the contact arrangement comprises a second current sensing element with a second predetermined resistance, wherein the second current sensing element is integrally formed with one of the bus bars included in the contact arrangement. In an optional implementation of the fifth example, the second current sensing element and the one bus bar of the contact arrangement, with which the second current sensing element is integrally formed, are formed of a same conductive material. This allows a redundant measurement of the contactor current, since two independent voltage detection signals are provided, which are both proportional to the contactor current. In this manner, a single point fault in one of the detection lines used for detecting the voltage drop across one of the first and the second current sensing elements only affects one of the two detection signals, and the determination of the contactor current can be continued.

According to a sixth example, the first current sensing element and the second current sensing element are integrally formed with a same bus bar included in the contact arrangement. In this manner, it is possible to introduce the redundancy in the contactor current measurement by only replacing a single bus bar from a common contactor device
According to a seventh example, the first current sensing element and the second current sensing element are integrally formed with different bus bars included in the contact arrangement. This allows to introduce the redundancy in the contactor current measurement to different bus bars of the contactor device and also allows to determine the contactor current in different locations on the current carrying path of the contactor device.

According to an eight example, the first current sensing element and the second current sensing element are formed of a same conductive material. In this manner, a fabrication of the bus bar including the first current sensing element and the second current sensing element can be simplified, since both current sensing elements can be fabricated through a same process.

Alternatively, according to a ninth example, the first current sensing element and the second current sensing element may be formed of different conductive materials.

According to a tenth example, the contactor device may further comprise at least one second actuator, which, upon activation, is configured to irreversibly prevent current flow through the contact arrangement. The integration of the second actuator further allows to integrate the functionalities of an overcurrent protection device into the contactor device. In an optional implementation of the third example, the second actuator is a pyrotechnic actuator, but the second actuator may also be a mechanical actuator. In another optional implementation of the third example, the second actuator is configured to irreversibly displace or irreversibly sever one or more of the at least one moveable bus bars, and/or the second actuator is configured to irreversibly displace or irreversibly sever one or more of the at least one fixed bus bars.

According to an eleventh example, at least a part of the first current sensing element defines a weak point, which supports the second actuator in severing the one bus bar, with which the first current sensing element is integrally formed. In an optional implementation of the eleventh aspect, also at least a part of the second current sensing element defines a (second) weak point, which supports the second actuator in severing the one bus bar, with which the second current sensing element is integrally formed. In this manner, the first current sensing element and/or the second current sensing element can integrate two functionalities and can support the breaking or bending of a bus bar after the second actuator is activated. Accordingly, it becomes unnecessary to specifically design a weak point in a bus bar, in which the first current sensing element and/or the second current sensing element are integrated.

According to a twelfth example, the weak point is formed as a predetermined breaking region, so that the respective bus bar is configured to break in the predetermined breaking region in response to the activation of the second actuator. With this implementation, the first current sensing element and/or the second current sensing element can support the second actuator in breaking the respective bus bar.

According to a thirteenth example, the weak point is formed as a hinge flexure, so that the respective bus bar is bendable around the hinge flexure in response to the activation of the second actuator. With this implementation, the first current sensing element and/or the second current sensing element can support the second actuator in bending or displacing the respective bus bar.

According to a fourteenth example, the contact arrangement includes a pair of moveable bus bars each having a moveable contact region and a pair of fixed bus bars each having a fixed contact region, wherein the at least one actuation element is configured to simultaneously move the pair of moveable bus bars when changing the state of the contactor device to and from the open state, and to and from the closed state, so that the moveable contact regions are electrically isolated from fixed contact regions in the open state, and the moveable contact regions are conductively coupled to the fixed contact regions in the closed state. Such an implementation allows the integration of a current shunt into a <NUM> pole combination contactor, which provides the functionality of two single contactor devices. In this manner, the integration of the functionalities of the contactor device can be further enhanced and the system integration can be simplified.

The present disclosure also relates to a high voltage power supply system, which comprises at least one battery and the contactor device.

Throughout this document, the term "terminal" is meant to describe a point at which a conductor from an electric device, an electric circuit or an electric component ends, and where a point is provided for electrically connecting an external electric device, an external electric circuit or an external electric component to this conductor. The term "node" may refer to a point where the terminals of one or more circuit components meet or may refer to the entire wire, which conductively couples the terminals of one or more electric circuit components. Further, the terms "electrically connected" and "conductively coupled" describe the establishing of an electrical connection between at least two electric devices, electric components or electric conductors, which allows the flow of electric current. Hereby, the electrical connection should not be restricted to a direct coupling of the terminals of the at least two electric devices, electric components or electric conductors, but other electric devices, electric components or electrical conductors may be coupled in between.

The accompanying drawings are incorporated into the specification and form a part of the specification to illustrate several examples of the present disclosure. These drawings, together with the description serve to explain the principles of the disclosure. The drawings are merely for the purpose of illustrating the preferred and alternative examples of how the disclosure can be made and used, and are not to be construed as limiting the disclosure to only the illustrated and described examples. Furthermore, several aspects of the examples may form-individually or in different combinations-solutions according to the present disclosure. The following described examples thus can be considered either alone or in an arbitrary combination thereof. Further features and advantages will become apparent from the following more particular description of the various examples of the disclosure, as illustrated in the accompanying drawings, in which like references refer to like elements, and wherein:.

The present disclosure will now be further explained referring to the Figures, and firstly referring to <FIG> shows a schematic perspective view of a first exemplary contactor device <NUM>. In an application scenario exemplarily described in the following the contactor device <NUM> may be used in a power supply system of an electric vehicle for controlling the power supply of electric loads like an electric motor, which are supplied at a predetermined high voltage. However, the contactor device <NUM> may also be used in other application scenarios, which require the storage and/or supply of high voltage energy in one or a plurality of high voltage batteries, like an energy storage system used in an electrical power grid.

The contactor device <NUM> comprises two fixed bus bars <NUM> and <NUM> and two moveable bus bars <NUM> and <NUM>, which form a contact arrangement of the contactor device <NUM>. In this manner, the contactor device <NUM> can function as a <NUM> pole combination contactor, which acts as a <NUM> pole single-break style contactor.

Advantageously, the design of the contact arrangement of the contactor device <NUM> allows that respectively one of the fixed bus bars <NUM> and <NUM> and respectively one of the moveable bus bars <NUM> and <NUM> can function as a first main contactor and the other one of the fixed bus bars <NUM> and <NUM> and the other one of the moveable bus bars <NUM> and <NUM> can function as a second main contactor, so that the contactor device can integrate the functionalities of two main contactors. However, the number of two moveable bus bars and two fixed bus bars is not essential for the functionality of contactor device <NUM>, but contactor device <NUM> may have more than two moveable bus bars and more than two fixed bus bars, or may have only one moveable bus bar and one fixed bus bar. Further, it is also conceivable, that the number of moveable bus bars differs from the number of fixed bus bars. For example, the principles of the present disclosure may also be applied to a contactor device, which comprises two fixed bus bars and one moveable bus bars, which is configured to reversibly connect the two fixed bus bars.

Turning back to <FIG>, it is schematically shown that the moveable bus bars <NUM> and <NUM> may be in a closed position, where each of the moveable bus bars <NUM> and <NUM> is conductively coupled to one of the fixed bus bars <NUM> and <NUM>, so that the contactor device is in a closed state. Accordingly, the closed state allows electric current flow between a first terminal <NUM>, which is integrally formed with the moveable bus bar <NUM>, and a second terminal <NUM>, which is integrally formed with the fixed bus bar <NUM>, and between a third terminal <NUM>, which is integrally formed with the moveable bus bar <NUM>, and a fourth terminal <NUM>, which is integrally formed with the fixed bus bar <NUM>. Alternatively, the moveable bus bars <NUM> and <NUM> may be in an open position, where each of the moveable bus bars <NUM> and <NUM> is electrically isolated from the fixed bus bars <NUM> and <NUM>, so that the contactor device is in an open state. Accordingly, the open state interrupts the current flow through the contact arrangement of the contactor device <NUM>.

For reversibly connecting and disconnecting the current path through the contactor device <NUM>, the contactor device <NUM> comprises an electromagnetic actuator <NUM> as an example of an actuation element. The electromagnetic actuator <NUM> is configured to reversibly move the moveable bus bars <NUM> and <NUM> between the closed position and the open position, in order to change a state of the contactor device <NUM> to and from the closed state and to and from the open state.

In order to facilitate the reversible transition between the open position and the closed position, the moveable bus bars <NUM> and <NUM> are formed in such a way that they are able to deflect elastically between the open and closed position in deflectable bus bar regions <NUM>, which constitute at least a part of the moveable bus bars <NUM> and <NUM>. For this purpose, the moveable bus bars <NUM> and <NUM> may be formed of a multi-layer structure, which comprises, for example, <NUM> to <NUM> layers of copper, aluminum or other suitable electrically conducting material. In addition, each of the moveable bus bars <NUM> and <NUM> may comprise a bulge <NUM>, for supporting the deflection capability of the moveable bus bars <NUM> and <NUM>. The bulge <NUM> may also contribute in applying a preload to the moveable bus bars <NUM> and <NUM>, which pushes the moveable bus bars <NUM> and <NUM> towards the open position.

The electromagnetic actuator <NUM> is configured to hold the moveable bus bars <NUM> and <NUM> in the closed position, when being powered. For this purpose, the deflectable bus bar regions <NUM> of the moveable bus bars <NUM> and <NUM> may be individually moved by the electromagnetic actuator <NUM>, for example by means of a shaft <NUM>, which is arranged on a top side of the moveable bus bars <NUM> and <NUM> in the deflectable bus bar region <NUM>. Additional spring elements may be arranged around the shaft <NUM>, which help to absorb small dislocations or imbalances between the moveable bus bars <NUM> and <NUM> during operation of the contactor device <NUM>, so as to prevent that such dislocations affect the electromagnetic actuator <NUM> or greatly impact the force applied between the fixed bus bars <NUM> and <NUM> and the moveable bus bars <NUM> and <NUM>. In this manner, tolerances between the fixed bus bars <NUM> and <NUM> and the moveable bus bars <NUM> and <NUM> introduced during fabrication of the contactor device <NUM> can be better compensated. Furthermore, a retaining spring <NUM> may be situated below each of the moveable bus bars <NUM> and <NUM>, i.e. on a bottom side of each of the moveable bus bars <NUM> and <NUM>, so as to bias the moveable bus bars <NUM> and <NUM> to be in the open position, when no force is applied by the shafts <NUM>, i.e. when the electromagnetic actuator <NUM> is not powered.

<FIG> shows the contactor device <NUM> in an unpowered state, where the electromagnetic actuator <NUM> is not energized, so that the moveable bus bars <NUM> and <NUM> are simultaneously in the open position. Accordingly, contact elements <NUM> of the moveable bus bars <NUM> and <NUM> are electrically isolated from contact elements <NUM> of the fixed bus bars <NUM> and <NUM> by a spatial gap, so that current flow through the contact arrangement of the contactor device <NUM> is interrupted. For reducing a contact resistance, the contact elements <NUM>, may be for example made of silver or any silver alloy, and may be mounted to the fixed bus bars <NUM> and <NUM> and the moveable bus bars <NUM> and <NUM> by welding, soldering or brazing. Each bus bar may comprise one or more than one contact element, and the contact elements of a bus bar form contact points, which together constitute the contact region of the bus bar for electrically contacting another bus bar of the contact arrangement. Of course, also other suitable electrically conducting materials or interconnection technologies may be used for forming the contact elements <NUM> on the bus bars of the contactor device <NUM>.

<FIG> shows the contactor device <NUM> in a powered state, where the moveable bus bars <NUM> and <NUM> are in the closed position, so that the contact points <NUM> of the moveable bus bars <NUM> and <NUM> are conductively coupled to the contact points <NUM> of the fixed bus bars <NUM> and <NUM>.

For bringing the moveable bus bars <NUM> and <NUM> from the open position into the closed position, the armature of the electromagnetic actuator <NUM>, applies a closing force to the moveable bus bars <NUM> and <NUM>, for example through the shafts <NUM>, thereby pushing the moveable bus bars <NUM> and <NUM> in a direction of the closing force, i.e. in a direction towards the fixed bus bars <NUM> and <NUM>.

As an alternative to the electromagnetic actuator <NUM>, the contactor device <NUM> may be equipped with a linear motor actuator as an actuation element, which moves the moveable bus bars <NUM> and <NUM> between the open position (shown in <FIG>) and the closed position (shown in <FIG>), by driving the shaft <NUM> with the linear motor actuator. In such a configuration, the shaft <NUM> is only moved, when the linear motor actuator is powered, so that the moveable bus bars <NUM> and <NUM> remain in the previous position, when the linear motor actuator is not powered. Accordingly, the linear motor actuator can function as a bi-stable actuator, which allows to introduce the open state and the closed state of the contactor device <NUM> as bi-stable states of the contactor device <NUM>, which are only changed, when the linear motor actuator is powered. Hence with such a configuration, when the linear motor actuator experiences a power loss, for example by a damage event, or due to a communication loss, the contactor device <NUM> can remain in the closed state (or open state).

Referring back to <FIG>, the contactor device <NUM> advantageously may further comprises a pyrotechnic actuator <NUM>, which is configured to permanently displace the fixed bus bars <NUM> and <NUM> into a fired position, after the pyrotechnic actuator <NUM> has been triggered (activated). In the fired position the fixed bus bars <NUM> and <NUM> are permanently electrically isolated from the moveable bus bars <NUM> and <NUM>. Hereby, the fixed bus bars <NUM> and <NUM> may be displaced as a whole, or may be displaced only in a displacement region <NUM> of the fixed bus bars <NUM> and <NUM>, which includes the contact elements <NUM>. In this manner, it can be prevented that the moveable bus bars <NUM> and <NUM> are still capable of conductively coupling to the fixed bus bars <NUM> and <NUM> after activation of the pyrotechnic actuator <NUM>. Consequently, current flow through the contact arrangement of the contactor device <NUM> is interrupted permanently after the activation of the pyrotechnic actuator <NUM>.

The pyrotechnic actuator <NUM> can comprise two or more pyrotechnic pins <NUM>, which cause ignition of a pyrotechnic charge, in response to the reception of an electric control signal. The pyrotechnic charge may be an explosive, which is directly ignited by the electric control signal or may be a gas generator charge, which suddenly expands after reception of the electric control signal. Alternatively, the pyrotechnic charge may have a multiple charge structure, comprising for example an initiator charge and a secondary gas generator charge.

Alternatively, the pyrotechnic pins <NUM> may be connected to an internal controller of the contactor device <NUM>, as it will be described later, or may be connected to an external controller, like a battery management system of a high voltage battery or an ECU or a crash sensor of a vehicle. The electric control signal for triggering the pyrotechnic actuator <NUM> can be, for example, issued by the internal controller or the external controller in response to a detected anomaly or a malfunction in any other circuit component of an electric circuit to which the contactor device <NUM> is conductively coupled or in response to the detection of an accident of the vehicle.

After activation, the pyrotechnic actuator <NUM> may drive, propelled by the ignition of the pyrotechnic charge, displacement elements <NUM> by means of a piston structure <NUM>, in order to push the fixed bus bars <NUM> and <NUM> into the fired position, where the fixed bus bars <NUM> and <NUM> are electrically isolated from the moveable bus bars <NUM> and <NUM>. For example, studs or bolts, which are driven by the energy of the piston structure <NUM> to displace or server the fixed bus bars <NUM> and <NUM> may serve as the displacement elements <NUM>.

In order to facilitate the displacement of the fixed bus bars <NUM> and <NUM>, a weak point (or a weak region) may be formed in each of the fixed bus bars <NUM> and <NUM>. The weak point may be formed for example in form of a hinge flexure <NUM>. In the shown example, the hinge flexure <NUM> is formed by a cut-out of the bus bar. A position of the cut-out, which forms the hinge flexure <NUM> may be adjusted in order to change the swinging radius of the displacement region <NUM> of the fixed bus bars <NUM> and <NUM>. In this manner, a movement path of the fixed bus bars <NUM> and <NUM> or at least of the displacement region <NUM> of the fixed bus bars <NUM> and <NUM> can be well defined, when the fixed bus bars <NUM> and <NUM> are moved into the fired position.

Alternatively, the weak point may be formed by a cut-out or a notch in the respective bus bar, which define a predetermined breaking region. In this manner, the weak point helps in severing or breaking the respective bus bar in the predetermined breaking region in response to the activation of the pyrotechnic actuator <NUM>.

An exemplary operation of the pyrotechnic actuator <NUM> is shown in <FIG>, which each show a schematic top view of contactor device <NUM>. <FIG> shows the contactor device <NUM> in the closed state before the pyrotechnic actuator <NUM> is activated. A holding force <NUM>, which points into the paper plane in this example, holds the moveable bus bars <NUM> and <NUM> in electrical contact with the fixed bus bars <NUM> and <NUM>.

<FIG> shows a top view of the of the contactor device <NUM> in a state where the pyrotechnic actuator <NUM> has been triggered. While only the fixed bus bar <NUM> is illustrated to be in the fired position, also the fixed bus bar <NUM> may be moved simultaneously the fired position after triggering the pyrotechnic actuator <NUM>. The pyrotechnically generated force drives the displacement elements <NUM> to irreversibly move the fixed bus bars <NUM> and <NUM> into the fired position, in order to electrically isolate the fixed bus bars <NUM> and <NUM> from the moveable bus bars <NUM> and <NUM>. As indicated by an arrow <NUM>, the fixed bus bars <NUM> and <NUM> or the displacement region <NUM> of the fixed bus bars <NUM> and <NUM> performs a rotational movement around the hinge flexure <NUM>, which defines the weak point of the fixed bus bars <NUM> and <NUM> in this example. This rotational movement preferably happens in a plane, which is perpendicular to the direction of the holding force <NUM> applied to the moveable bus bars <NUM> and <NUM> by the electromagnetic actuator <NUM>. However, not in all cases the plane, in which the fixed bus bars <NUM> and <NUM> or the displacement region <NUM> of the fixed bus bars <NUM> and <NUM> move into the fired position, must be perpendicular to the direction of the holding force <NUM>. Instead, this plane may only enclose a predetermined angle with the direction of the holding force <NUM>, so that the direction of movement of the fixed bus bars <NUM> and <NUM> or of the displacement region <NUM> of the fixed bus bars <NUM> and <NUM> at least comprises an angle with respect to the movement direction of the moveable bus bars <NUM> and <NUM> between the open position and the closed position.

In this manner, it can be ensured that the fixed bus bars <NUM> and <NUM> can be moved into the fired position, without affecting the actuation mechanism for moving and holding the moveable bus bars <NUM> and <NUM> in the closed position. Similarly, it is prevented that the motion of the fixed bus bars <NUM> and <NUM> into the fired position is affected by the actuation mechanism for moving and holding the moveable bus bars <NUM> and <NUM> in the closed position, as the force generated by the pyrotechnic actuator <NUM> is transmitted in such a way to the fixed bus bars <NUM> and <NUM> that it does not work against the forces generated by the electromagnetic actuator <NUM>. Similar the movement of the fixed bus bars <NUM> and <NUM> or of the displacement region <NUM> into the fired position is not restricted to a rotational movement, but may follow a linear movement path.

Notable, the same principles as described above may be applied to the moveable bus bars <NUM> and <NUM>, so that the pyrotechnic actuator <NUM> may not permanently displace or sever the fixed bus bars <NUM> and <NUM>, but the moveable bus bars <NUM> and <NUM>. Alternatively, a second pyrotechnic actuator may be provided for the contactor device <NUM>, so that respectively one dedicated pyrotechnic actuator permanently displaces or severs the fixed bus bars <NUM> and <NUM>, and respectively one dedicated pyrotechnic actuator permanently displaces or severs the moveable bus bars <NUM> and <NUM>. Furthermore, instead of using the energy of one or more pyrotechnic actuator(s) for severing and/or displacing one or more bus bars of the contactor device <NUM>, the energy of one or more mechanical actuators may be used. The mechanical actuator may, for example, be a biased spring, which is configured to permanently sever and/or displace one or more bus bars of the contactor device <NUM>, after the mechanical actuator has been triggered (activated), for example by releasing the biased spring.

In another alternative, instead of mechanically moving one or more bus bar(s) of the contactor device <NUM> into the fired positon (or breaking the one or more bus bars), the fixed bus bars <NUM> and <NUM> may be irreversibly separated from the moveable bus bars <NUM> and <NUM>, by driving at least one isolation cap, which is formed of electrically insulating material, to completely encompass an end region of the fixed bus bars <NUM> and <NUM> after activation of the pyrotechnic actuator <NUM>. In this manner, the isolation cap interrupts the current flow through contact arrangement of the contactor device <NUM> and at the same time suppress the formation of electric arcs. Details on this activation mode are further explained with respect to Figs. <NUM> and <NUM> of European patent application <CIT>, which is incorporated herein by reference.

<FIG> shows the contactor device <NUM> together with an optional contactor housing <NUM>, which houses a significant part of the internal components of the contactor device <NUM>. In this example, only the terminals <NUM> and <NUM> of the fixed bus bars <NUM> and <NUM> and the terminals <NUM> and <NUM> of the moveable bus bars <NUM> and <NUM> are not enclosed by the contactor housing <NUM>. However, the terminals <NUM>, <NUM>, <NUM> and <NUM> may be formed by connectors, instead, and the connectors may be integrated into the contactor housing <NUM>. The contactor housing <NUM> may be a sealed housing, which may be filled with a vacuum or an electronegative gas, in order to suppress the formation of arcs, when opening the moveable contacts <NUM> and <NUM>. However, by the specific design of the moveable bus bars <NUM> and <NUM> already under normal atmosphere sufficient electrical isolation between the moveable bus bars <NUM> and <NUM> and the fixed bus bars <NUM> and <NUM> can be provided. Accordingly, it is not essential to seal the contactor housing <NUM> or for to use a vacuum or an electronegative gas. Furthermore, while the terminals <NUM>, <NUM>, <NUM> and <NUM> have been shown in <FIG> as bolt interfaces, it is also possible to use weld interfaces or connectors, which are, for example, provided as part of the connector housing <NUM> instead.

<FIG> shows a schematic circuit diagram of the contactor device <NUM>, conductively coupled to a high voltage battery <NUM>. In the shown example, the first terminal <NUM> of the contactor device <NUM> is electrically connected to a positive terminal of the HV battery <NUM>. The second terminal <NUM> may be electrically connected to the positive voltage side of a high voltage DC bus, which is supplied by the power of the HV battery <NUM>. Similar the third terminal <NUM> is electrically connected to a negative terminal of the HV battery <NUM>. The second terminal <NUM> may be electrically connected to the negative voltage side of a HV DC bus. Accordingly, in the shown example, the fixed bus bar <NUM> and the moveable bus bar <NUM> function as a positive main contactor (schematically illustrated by reference numeral <NUM>), which can be opened and closed for controlling the electrical connection between the battery <NUM> and the positive side of the HV DC bus. Similar, the fixed bus bar <NUM> and the moveable bus bar <NUM> function as a negative main contactor (schematically illustrated by reference numeral <NUM>), which can be opened and closed for controlling the electrical connection between the battery <NUM> and the positive side of the HV DC bus.

As described above, and schematically shown in <FIG>, the two moveable bus bars <NUM> and <NUM> are moved by the same actuation element <NUM>, in order to change the state of the contactor device <NUM> to and from the open state, where the HV DC bus is disconnected from the HV battery <NUM>, and to and from the closed state, where the HV DC bus is connected to the HV battery <NUM>.

<FIG> further illustrates a first aspect of the present disclosure, namely the integration of a (first) current sensing element <NUM>, which may be also signified as a shunt resistor or shunt current sensor, into the contactor device <NUM>. The current sensing element <NUM> is integrally formed with one of the bus bars of the contactor device <NUM>, here for example with the moveable bus bar <NUM>. In this manner, it is not required anymore to connect a separate shunt current sensor in series with the contactor device <NUM> and the HV battery <NUM>. Accordingly, the integration of the first current sensing element <NUM> within the contactor device <NUM> allows to get rid of the (bolted) interconnection between the current sensing element <NUM> and one of the main contactors <NUM> and <NUM> formed by the contact arrangement of the contactor <NUM>.

As a consequence, the moveable bus bar <NUM> includes the current sensing element <NUM>, which has a predefined resistance and can be used for measuring a battery current provided by the HV battery <NUM>. Since the battery current corresponds to a current flowing through the contactor device, it is throughout this document also signified as "contactor current". In order to measure a voltage dropping across the first current sensing element <NUM>, the contactor device <NUM> comprises detection nodes <NUM> and <NUM>. A battery management system of the battery <NUM> or another external controller of the HV power supply system, in which the contactor <NUM> is used, can be electrically connected to the detection nodes <NUM> and <NUM>, for example by means of a wire harness or a flex circuit. The BMS or external controller can then determine the battery current Ibat as <MAT> wherein VRes describes the detected voltage dropping across the first current sensing element <NUM>, and R describes the predefined resistance of the first current sensing element <NUM>. In addition to the voltage drop across the first current sensing element <NUM>, the BMS or the external controller may also determine the temperature of the first current sensing element <NUM> and may correct the resistance value by considering the temperature coefficient of resistance (TCR). In this manner, it is possible to take into account the temperature-dependency of the resistance of the first current sensing element, so that the battery current can be determined more precisely.

<FIG> schematically illustrate the integration of the first current sensing element <NUM> into one of the bus bars of the contact arrangement of the contactor <NUM>. In the following, the moveable bus bar <NUM>, which is arranged on the negative output side of the HV battery <NUM> in the example of <FIG>, is shown as an example of one bus bar of the contactor device <NUM>, which is integrally formed with the first current sensing element <NUM>. However, the first current sensing element may instead be integrally formed with the fixed bus bar <NUM>, which is arranged on the negative output side of the HV battery <NUM> in the example of <FIG>, or with one of the moveable bus bar <NUM> or the fixed bus bar <NUM>, which are arranged on the positive output side of the HV battery <NUM> in the example of <FIG>. In <FIG>, the dimensions and shape of the exemplary bus bar is shown only schematically, and it should be noted that the inventive concept described with respect to this Figures may in particular be applied to one or more of the moveable bus bars <NUM> and <NUM> and the fixed bus bars <NUM> and <NUM> of the contactor device <NUM> as shown and described with reference to <FIG>.

<FIG> shows the moveable bus bar <NUM> in form of an interconnected tri-band, which comprises a first bus bar part <NUM>(<NUM>), a second bus bar part <NUM>(<NUM>) and the current sensing element <NUM>, which is arranged between the first bus bar part <NUM>(<NUM>) and the second bus bar part <NUM>(<NUM>). As described above, the first bus bar part <NUM>(<NUM>) and the second bus bar part <NUM>(<NUM>) may be formed of copper, aluminum or any other suitable electrically conducting material known in the art. In the shown example, the current sensing element <NUM> is preferably formed as a manganin strip, which is fixedly connected to the first bus bar part <NUM>(<NUM>) and the second bus bar part <NUM>(<NUM>) at interconnection interfaces <NUM> and <NUM> by welding the manganin strip to the first bus bar part <NUM>(<NUM>) and to the second bus bar part <NUM>(<NUM>).

Other than manganin, it can be also possible to form the current sensing element <NUM> from Isotan, Isabellin, or constatan, or from another copper alloy containing Copper, Mangan, and/or Nickel. However, also other suitable materials known in the art, which allow to fabricate the current sensing element <NUM> with a well-defined resistance are conceivable. Instead of welding, the current sensing element <NUM> may be interconnected to the the first bus bar part <NUM>(<NUM>) and to the second bus bar part <NUM>(<NUM>) by soldering or brazing or any other suitable interconnection method, which introduces only a small resistance at the interconnection interfaces <NUM> and <NUM>.

Alternatively, the current sensing element <NUM> may be directly formed out of the moveable bus bar <NUM>, and accordingly may be formed of a same material as the current sensing element. In this exemplary implementation, the predetermined resistance of the current sensing element <NUM> may be defined as a region of the first bus bar <NUM>, which is formed with a specific geometry, so that the region forming the current sensing element <NUM> has a predefined resistance. For example, a constriction, which has a predetermined width and/or thickness in a direction transverse to a main direction of the current flow, may be formed in the moveable bus bar <NUM> to serve as the current sensing element <NUM>. As a technique for forming the current sensing element <NUM> from the the moveable bus bar <NUM>, for example stamping or punching may be used. Alternatively, it is also conceivable, that certain parts of precast bus bars are cut out in order to integrate the current sensing element <NUM> into the bus bar.

By directly forming the current sensing element <NUM> from a bus bar of the contactor device <NUM>, it is possible to directly fabricate the respective bus bar with the current sensing element in one piece. Accordingly, it is also possible to further reduce the resistance of the interconnection interfaces <NUM> and <NUM>, since no additional interface resistance needs to be introduced.

<FIG> shows an exemplified arrangement of the first current sensing element <NUM> between the contact element <NUM> of the moveable bus bar <NUM> and the third terminal <NUM> (not shown in <FIG>), which is integrally formed with the moveable bus bar <NUM>. Here, the second bus bar part <NUM>(<NUM>) may for example include the deflectable bus bar region <NUM>, so that the current sensing element <NUM> is arranged within a static region of the moveable bus bar <NUM>, which is not affected by the actuation of the electromagnetic actuator <NUM>. Accordingly, it is avoided that changing the state of the contactor device has an influence on the detection of the battery current, for example due to a change in the resistance of the current sensing element <NUM>.

In another advantageous configuration, the current sensing element <NUM> may be arranged in one of the bus bars of the contactor <NUM> as the weak point, which facilitates the displacement or severing of the respective bus bar. For example, the current sensing element <NUM> may be arranged as the hinge flexure <NUM>, which was described with respect to <FIG>, in one of the bus bars of the contactor device <NUM> and allows to displace the respective bus bar. Alternatively, the current sensing element <NUM> may define a predetermined breaking region, which helps in severing or breaking the respective bus bar in the predetermined breaking region in response to the activation of the pyrotechnic actuator <NUM> similar as it has been described above especially with respect to <FIG>.

<FIG> shows another advantageous configuration of the moveable bus bar <NUM>. In addition to the (first) current sensing element <NUM>, the moveable bus bar <NUM> may also comprise a (second) current sensing element <NUM>. Like, the first current sensing element <NUM>, the second current sensing element <NUM> may be formed as a manganin strip, which is fixedly connected to the second bus bar part <NUM>(<NUM>) and a third bus bar part <NUM>(<NUM>) at interconnection interfaces <NUM> and <NUM> by welding the manganin strip to the first bus bar part <NUM>(<NUM>) and to the second bus bar part <NUM>(<NUM>). However, also the other fabrication techniques and interconnection techniques as described above for integrating the first current sensing element <NUM> may be used to integrate the second current sensing element <NUM> into the moveable bus bar <NUM> or any of the bus bars of the contactor device <NUM>. Hereby, each of the first and the second current sensing elements <NUM> and <NUM> may be formed of the same conductive material, or the first and the second current sensing elements <NUM> and <NUM> may be formed of different conductive materials.

The integration of a second current sensing element allows a redundant measurement of the battery current, since respectively one voltage drop across each of the first and the second current sensing elements <NUM> and <NUM> may be measured, so that two independent voltage detection signals are provided, which are both proportional to the battery current. In this manner, a single point fault in one of the detection lines used for detecting the voltage drop across each of the first and the second current sensing elements <NUM> and <NUM> only affects one of the two detection signals, and the determination of the battery current can be continued.

Apparently, the first current sensing element <NUM> and the second current sensing element <NUM> may not necessarily be arrangend in a same bus bar of the contactor device <NUM>, but may be provided in different bus bars of the contactor device. For example, the first current sensing element <NUM> may be part of one of the fixed bus bar <NUM> and the moveable bus bar <NUM>, which are electrically connected with the the negative output side of the HV battery <NUM> in the example of <FIG>, and the second current sensing element <NUM> may be part of one of the fixed bus bar <NUM> and the moveable bus bar <NUM>, which are electrically connected with the the positive output side of the HV battery <NUM> in the example of <FIG>. Furthermore, it is also possible that more than two current sensing elements are integrally formed with the bus bars of the contactor device <NUM>.

<FIG> shows a schematic circuit diagram of a second exemplary contactor device <NUM>, being conductively coupled to the high voltage battery <NUM>. Hereby, the elements of the second exemplary contactor device <NUM>, which correspond to elements of the first exemplary contactor device <NUM>, are referenced with corresponding reference numerals. The second exemplary contactor device <NUM> benefits from a second aspect of the present disclosure, namely the integration of an assembled circuit, which allows to transfer at least a part of the functions of the battery management system of battery <NUM> to the contactor device <NUM> or to allow the contactor device <NUM> to integrate the battery management system of the battery <NUM>, so that the contactor device can function more independently. As will become apparent in the following, the integration of the assembled circuit may be performed together with the integration of the at least one current sensing element <NUM>.

The assembled circuit <NUM> comprises a control circuit, which is configured to control the operation of the electromagnetic actuator <NUM> in order to open and close the positive main contactor <NUM> formed by the movable bus bar <NUM> and the fixed bus bar <NUM>, and the negative main contactor <NUM> formed by the movable bus bar <NUM> and the fixed bus bar <NUM> as schematically shown in <FIG> by the lines <NUM>, <NUM> and <NUM>. In this manner, the control circuit of the assembled circuit <NUM> can directly overtake the control for the actuator <NUM>, so that it becomes unnecessary to implement a control function for the actuator <NUM> in a battery management system of the HV battery <NUM> or in another external controller of a HV power supply system, which comprises the HV battery <NUM>. The control circuit can control the operation of the electromagnetic actuator <NUM> in accordance with an operational parameter, which is determined by a processing circuit of the assembled circuit. The operational parameter can be a control command received by the processing circuit from an external controller, like a BMS of the battery <NUM>, which is arranged external to the contactor device <NUM>, or a vehicle ECU, for changing the state of the contactor device <NUM> by operating the electromagnetic actuator <NUM> or a control command received by the processing circuit from the external entity for activating the pyrotechnic actuator. Alternatively, the operational parameter may be a measured value, which is either directly determined by the processing circuit or is determined by the external controller and communicated to the processing circuit. The measured value can be one of the battery current, a contactor voltage, which indicates a voltage dropping between the first terminal <NUM> and the second terminal <NUM> or a voltage dropping between the third terminal <NUM> and the fourth terminal <NUM>, or a leakage path resistance, which exists between a grounding terminal (or voltage reference terminal) of the assembled circuit and at least one of the bus bars of the contactor device <NUM>.

The assembled circuit <NUM> may further comprise several peripheral circuits, like a communication circuit, which enables communication between the processing circuit and one or more external controllers, so that the processing circuit can receive and/or transmit control commands to and from the one or more external controllers, which can thus monitor the operation of the contactor device <NUM>. Communication between the communication circuit and the external controller may for example be performed, by using a CAN (Controller Area Network) bus and the CAN protocol, by using an isoSPI (isolated Serial Port Interface) interface and the isoSPI protocol, or by using Ethernet. However, also other known on-board networks and industrial communication protocols may be used.

The peripheral circuits may, for example, also comprise a power supply unit, which supplies power to the circuits of the assembled circuit <NUM>. Hereby, it is possible that the assembled circuit <NUM> is directly supplied from the HV battery <NUM>. But also another (external) power source for the supply of the assembled circuit <NUM> is conceivable.

The various circuits of the assembled circuit <NUM> may be mounted on a single component carrier, to form the assembled circuit as an integrated component. Hereby the term integrated component especially refers to the fact, that all components of the assembled circuit are packaged together as a single compact component. For example, a printed circuit board (PCB) may be used as the component carrier, and by mounting the assembled circuit <NUM> on the PCB, the PCB becomes an assembled printed circuit board (PCBA).

To further enhance the level of integration, the assembled circuit <NUM>, for example mounted on the PCB to form the PCBA, can be arranged within the contactor housing <NUM> (shown in <FIG>). For example, the connector housing may allow to provide a specific housing portion for the assembled circuit <NUM> and/or may provide specific cooling channels for effectively cooling the assembled circuit <NUM>. The connection interfaces, which are necessary for allowing wired connection between the assembled circuit <NUM> and the external controller may be provided in the form of connectors, which are integrated into the contactor housing <NUM>. However, it is also conceivable that the communication circuit of the assembled circuit <NUM> allows wireless communication with the external circuit.

Furthermore, it is possible that the contactor device <NUM> is not housed in the contactor housing <NUM>. In this case, the PCBA, onto which the assembled circuit <NUM> is mounted, may be fixed to the contactor device <NUM>, for example by screwing or welding. In such implementation, protection for the PCBA may be for example provided by a protective coating or by overmolding the PCBA.

Besides receiving the measured value from the external controller, the integration level of the contactor device <NUM> may be further enhanced by implementing additional detection functions in the assembled circuit, in order to allow the assembled circuit to directly detect and/or determine at least one of the battery current, the contactor voltage or the leakage path resistance.

In a first example, the assembled circuit <NUM> comprises a first detection circuit, which is configured to detect a first detection voltage, which is indicative of the battery current (or contactor current).

For this purpose, the contactor device <NUM> also includes the integrated current sensing element <NUM>, which is integrally formed with one of the bus bars of the contactor <NUM>. Herein, the current sensing element <NUM> may be designed in any of the ways, which have been described with reference to the first exemplary contactor device <NUM>, and here especially with reference to <FIG>. In order to measure the voltage drop across the current sensing element <NUM>, the first detection circuit may be electrically connected through detection wires <NUM> and <NUM> to detection nodes <NUM> and <NUM> of the bus bar (in this example the moveable bus bar <NUM>), with which the current sensing element <NUM> is formed. As described above, more than one current sensing element may be integrally formed with the bus bars of the contactor device <NUM>. In this case, the first detection circuit may be electrically connected to each of the current sensing elements individually through detection wires and may measure a voltage drop across each of the current sensing elements individually.

It is essential that an integrated current sensor element is integrally formed with the contactor device <NUM>.

On the basis of the detected voltage drop, the processing circuitry is configured to determine the contactor current by using equation (<NUM>) described above, wherein the detected first detection voltage is used as the detected dropping voltage VRes and the resistance of the respective current sensing element (or external shunt) as the predefined resistance R. Alternatively, in order to determine the contactor current, the processing circuit may communicate the detected first detection voltage to the external controller and the external controller may calculate the contactor current and communicate the result of the calculation back to the processing circuit.

Based on the result of the determination of the contactor current, the control circuit controls the operation of the electromagnetic actuation element <NUM> and may optionally also control the activation of the pyrotechnic actuator or an external fuse (for example fuse <NUM> shown in <FIG>). For example, due to electromagnetic forces, it may not be possible to separate the moveable contacts <NUM> and <NUM> from the fixed contacts <NUM> and <NUM>, when the contactor current (or battery current) exceeds a predetermined current threshold. Accordingly, if the control circuit determines that the determined contactor current is larger or equal to the predetermined current threshold, the control circuit does not actuate the electromagnetic actuator <NUM>, but issues an activation signal to activate the pyrotechnic actuator or an external fuse instead. However, in some exemplary configurations this activation signal may be issued instead by the external controller, if the external controller determines that the control circuit is unable to interrupt the contactor current through the actuating the electromagnetic actuator <NUM>.

In a second example, the assembled circuit <NUM> comprises a second detection circuit which is configured to detect a second detection voltage, which is indicative of the contactor voltage. For this purpose, the second detection circuit may determine a voltage dropping across the negative main contactor <NUM>, i.e. a voltage dropping between the moveable bus bar <NUM> and the fixed bus bar <NUM>. For detecting the voltage drop between the moveable bus bar <NUM> and the fixed bus bar <NUM>, the second detection circuit may be electrically connected through the detection wire <NUM> to the detection node <NUM> of the moveable bus bar <NUM> and through a detection wire <NUM> to a detection node <NUM> of the fixed bus bar <NUM>.

Alternatively, or in addition the second detection circuit may determine a voltage dropping across the positive main contactor <NUM>, i.e. a voltage dropping between the moveable bus bar <NUM> and the fixed bus bar <NUM>. For detecting the voltage drop between the moveable bus bar <NUM> and the fixed bus bar <NUM>, the second detection circuit may be electrically connected through a detection wire <NUM> to a detection node <NUM> of the fixed bus bar <NUM> and through a detection wire <NUM> to a detection node <NUM> of the moveable bus bar <NUM>.

On the basis of the detected voltage drop(s), the processing circuitry is configured to determine the contactor voltage as the voltage dropping across one of the main contactors <NUM> and <NUM> or as an average of these voltages. Again, the determination of the contactor voltage may include that the processing circuit communicates the detected second detection voltage to the external controller and the external controller calculates the contactor voltage and communicate the result of the calculation back to the processing circuit. By implementing the detection of the contactor voltage as a function of the assembled circuit <NUM>, the state of the contactor device <NUM> can be confirmed by the assembled circuit <NUM> and/or by an external controller, which monitors the operation of the contactor device <NUM>, so that a determination of the contactor health and wearing can be performed.

Based on the result of the determination of the contactor voltage, the control circuit controls the operation of the electromagnetic actuator <NUM>. For example, due to possible current peaks, which may harm components electrically connected to the HV DC bus, like a DC link capacitor, the control circuit may only actuate the electromagnetic actuator <NUM> to bring the moveable bus bars <NUM> and <NUM> in the closed position, if the determined contactor voltage is equal or smaller than a predetermined voltage threshold, but will refrain from actuating the electromagnetic actuator <NUM>, if the determined contactor voltage is larger than the predetermined voltage threshold.

In order to reduce the contactor voltage before changing the state of the contactor device <NUM>, the assembled circuit may further include a precharge circuit <NUM>, which may be electrically connected in parallel to one of the main contactors <NUM> and <NUM>. <FIG> shows a schematic circuit diagram of an exemplary precharge circuit <NUM>, which is electrically connected in parallel to the positive main contactor <NUM> by electrically connecting the precharge circuit with a node <NUM> provided on the moveable bus bar <NUM> and with a node <NUM> provided on the fixed bus bar <NUM> for electrically connecting the precharge circuit to the respective bus bar. The precharge circuit comprises at least one precharge resistor <NUM> and at least one precharge switch <NUM>, which are conductively coupled in series in between the nodes <NUM> and <NUM>. In this manner, the precharge circuit <NUM> allows to optionally bypass the main contactor <NUM> formed by the contact points of the moveable bus bar <NUM> and the fixed bus bar <NUM>, in order to short circuit the terminals <NUM> and <NUM> of the contactor device when the precharge switch <NUM> is closed.

The resistance of the precharge resistor <NUM> may be chosen depending on application scenarios, so as to limit the maximal current flowing through the precharge circuit <NUM>, so that dangerous current peaks can be avoided when the precharge switch <NUM> is closed. The precharge switch <NUM> can be a semiconductor switch, for example a metal-oxide-semiconductor field-effect transistor or an insulated-gate bipolar transistor (IGBT), which can easily be integrated into the assembled circuit <NUM>. But also another type of precharge relay may be used.

The opening and closing of the precharge switch <NUM> may be controlled by the control circuit of the assembled circuit <NUM> or maybe controlled by the external controller dependent on the contactor voltage. For example, if it is determined that the contactor voltage is larger than the predetermined voltage threshold, the electromagnetic actuator <NUM> is not actuated, but the precharge switch <NUM> is closed. As soon as the contactor voltage reaches or decreases below the predetermined voltage threshold, the electromagnetic actuator <NUM> may be actuated to bring the moveable contacts <NUM> and <NUM> in the closed position, so as to allow current flow through the main contactors <NUM> and <NUM>. In this manner, the contactor device <NUM> is only brought into the closed state, when the contactor voltage is equal or smaller than the predetermined voltage threshold, so that the risk for generating hazardous current peaks after closing the moveable contacts <NUM> and <NUM> can be significantly reduced. Since the precharge circuit <NUM> is an integral part of the assembled circuit <NUM>, it is directly integrated in the contactor device <NUM>, so that the need for connecting an external precharge circuit to the contactor device <NUM> is dispensed.

In a third example, the assembled circuit <NUM> comprises a third detection circuit which is configured to detect a third detection voltage, which is indicative of the leakage path resistance between one of the bus bars of the contactor device <NUM> and a grounding potential (or reference potential), which may for example correspond to the potential of the chassis of a vehicle. For the purpose of leakage path resistance detection, the third detection circuit may be part of a leakage path resistance detection circuit. A circuit diagram of an exemplary leakage path resistance detection circuit <NUM> is shown in <FIG>. The leakage path resistance detection circuit <NUM> is here for example conductively coupled with a node <NUM> to the moveable bus bar <NUM> and with a node <NUM> to a grounding terminal <NUM> of the contactor device, which may be electrically connected to a chassis of a vehicle or another reference potential.

The leakage path resistance detection circuit <NUM> comprises at least a first leakage path resistance detection resistor <NUM> and a second leakage path resistance detection resistor <NUM>, which are conductively coupled in series with a node <NUM> between the moveable bus bar <NUM> and the grounding terminal <NUM>. A leakage path resistance detection switch <NUM> is conductively coupled in parallel to the first leakage path resistance detection resistor <NUM>, so as to optionally bypass (short circuit) the first leakage path resistance detection resistor <NUM>, when the leakage path resistance detection switch <NUM> is closed. The leakage path resistance detection switch <NUM> can be a semiconductor switch, for example a metal-oxide-semiconductor field-effect transistor or an insulated-gate bipolar transistor (IGBT), which can easily be integrated into the assembled circuit <NUM>. But also another type of relay may be used.

The third detection circuit (see reference numeral <NUM> in <FIG>) is conductively coupled with the node <NUM> between the first leakage path resistance detection resistor <NUM> and the second leakage path resistance detection resistor <NUM>. The third detection circuit is configured to detect a first leakage path resistance detection voltage Vleak,<NUM> across the second leakage path resistance detection resistor <NUM>, when the leakage path resistance detection switch <NUM> is open, and to detect a second leakage path resistance detection voltage Vleak,<NUM> across the second leakage path resistance detection resistor <NUM>, when the leakage path resistance detection switch <NUM> is closed.

Based on the detected leakage path resistance detection voltages Vleak,<NUM> and Vleak,<NUM>, the processing circuitry is configured to determine the leakage path resistance of the contact arrangement of the contactor by using the following equation (<NUM>), <MAT> where Vbat is the voltage of the battery <NUM> and RST1 is the resistance of the leakage path resistance detection circuit <NUM> when the leakage path resistance detection switch <NUM> is closed. A more detailed description of the leakage path resistance determination can be found with respect to the description of <FIG> of European patent application <CIT>, which is incorporated herein by reference. More details of possible leakage path resistance detection circuits <NUM> can be found in the description of <FIG> of European patent application <CIT>. Of course, the circuits, and methods, which are disclosed in European patent application <CIT> can also be implemented for the leakage path resistance detection of the assembled circuit <NUM>. But also other known leakage path resistance circuits, and detection methods may be implemented for the leakage path resistance detection of the assembled circuit <NUM>.

Instead of electrically connecting the leakage path resistance detection circuit <NUM> to the moveable bus bar <NUM>, the leakage path resistance detection circuit <NUM> may be electrically connected to another bus bar of the contactor <NUM>. Furthermore, the leakage path resistance detection may be performed for more than one bus bar of the contactor <NUM>. In particular, it is especially advantageous, if the leakage path resistance detection is performed for one bus bar, which is part of the positive main contactor <NUM> and for one bus bar, which is part of the negative main contactor <NUM>.

Again, the determination of the leakage path resistance may include that the processing circuit communicates the detected third detection voltage to the external controller and the external controller may calculate the leakage path resistance of the contact assembly and communicate the result of the calculation back to the processing circuit.

Based on the result of the determination of the leakage path resistance, the control circuit controls the operation of the electromagnetic actuator <NUM> or may activate the pyrotechnic actuator <NUM>. In particular, the control circuit may be configured to control the electromagnetic actuator <NUM> to change the state of the contactor device <NUM> to the open state, if the control circuit determines that the leakage path resistance of the assembled circuit (i.e. of any bus bar of the assembled circuit) is equal or smaller than a predetermined resistance threshold. If it is not possible to move the moveable contacts anymore, for example because the contactor current is above the predetermined current threshold, the control circuit is configured to activate the pyrotechnic actuator <NUM> in order to interrupt the current flow through the contactor device permanently. Alternatively, in some exemplary configurations the command for opening the moveable contacts <NUM> and <NUM> or the activation signal for activating the pyrotechnic actuator may be issued instead by the external controller and be processed by the processing circuit and the control circuit of the assembled circuit, if the external controller determines that the leakage path resistance of the assembled circuit is equal or smaller than a predetermined resistance threshold.

The detection wires <NUM>, <NUM>, <NUM>, <NUM> and <NUM>, which electrically connect the individual detection circuits to the respective detection nodes, as well as other wires, which electrically connect components of the assembled circuit, like the precharge circuit <NUM> and the leakage path resistance detection circuit <NUM> with one or more of the bus bars of the contactor device <NUM>, may be provided in form of a wire harness or in form of conductors of a flexible PCB. The latter option for example allows to directly integrate the assembled circuit on the flexible PCB in order to further enhance the integration level of the contactor device <NUM>.

Notably, the functionalities of each circuit of the assembled circuit <NUM> may be realized by software, hardware, or software in cooperation with hardware. Furthermore, each circuit of the assembled circuit <NUM> can be realized as a dedicated integrated circuit and the dedicated integrated circuits are assembled to form the assembled circuit. Alternatively, the functionalities of each circuit may be integrated into a common integrated circuit, which forms the assembled circuit. Alternatively, one or more circuits of the assembled circuit may be realized by using general-purpose processors, special-purpose processors, or FPGAs (Field Programmable Gate Array) that can be programmed.

Furthermore, the voltage detection circuits of the assembled circuit may be formed by dedicated analog to digital converters (ADC-converters), or may be formed by a single ADC converter, which performs the individual voltage detections as described above in a serial order.

The present disclosure also relates to a high voltage power supply system, which comprises the first exemplary contactor device <NUM> or the second exemplary contactor device <NUM> and the battery <NUM>. The HV power supply system may further comprise the external controller, for example a BMS of the battery <NUM> or the vehicle ECU, which control the operation of the battery <NUM>. As described above, the external controller may control the operation of the contactor device either alone (for the contactor device <NUM>) or in interplay with an internal controller (assembled circuit <NUM>) of the contactor (contactor device <NUM>). Hereby, it is possible that the internal controller can overtake at least a part functionalities of the external controller and accordingly can at least partly control the contactor device independent from the external controller. In particular, the internal controller in form of the assembled circuit <NUM> may even replace the BMS of the battery <NUM>. Furthermore, the contactor devices <NUM> and <NUM> may allow to directly electrically connect the contactor device <NUM> or <NUM> to the HV battery <NUM> without connecting external bus bars in between. This may be achieved, by extending the length of the bus bars of the contact assembly on the side of the battery, for example the moveable bus bars <NUM> and <NUM> in the described examples. This reduces the likelihood of a short circuit during assembling of the HV power supply system or in case of a vehicle crash. Further, the contactor devices <NUM> and <NUM> can be installed within a battery pack formed by the HV battery <NUM> by only connecting two conductive element.

As should have been apparent from the above description, the ideas of the first aspect of the present disclosure the ideas of the second aspect of the present disclosure may be combined individually or in combination to enhance the integration level of a contactor device and to help in providing a cheap, space-and weight saving contactor device.

Claim 1:
A contactor device (<NUM>) comprising:
a contact arrangement, which includes at least one moveable bus bar (<NUM>, <NUM>) and at least one fixed bus bar (<NUM>, <NUM>), wherein the at least one moveable bus bar (<NUM>, <NUM>) has a first contact region and the at least one fixed bus bar (<NUM>, <NUM>) has a second contact region;
at least one actuation element (<NUM>), which is configured to change a state of the contactor device (<NUM>) at least to and from an open state, and to and from a closed state, wherein
in the open state the first contact region is electrically isolated from the second contact region, and in the closed state the first contact region is conductively coupled to the second contact region;
wherein the contact arrangement comprises a first current sensing element (<NUM>) with a first predetermined resistance;
characterised in that the first current sensing element (<NUM>) is integrally formed with one of the bus bars (<NUM>, <NUM>, <NUM>, <NUM>) included in the contact arrangement.