Integrated Power Box

Abstract

Power arrangement (10) for a vehicle, comprising an AC charger (12) for connecting to an external AC power supply (38) and providing a high-voltage direct current (HV DC) voltage (40) for the vehicle, a DC / DC converter (16) for converting the HV DC voltage (40) into a vehicle electrical system voltage, and an HV voltage distribution unit (18) for distributing the HV DC voltage (40) in the vehicle, wherein the AC charger (12) is implemented using semiconductor technology without galvanic isolation, and wherein the power arrangement (10) comprises a housing (22) in which the AC charger (12), the HV temperature control unit (14), the DC / DC converter (16), and the HV voltage distribution unit (18) are arranged to form an integrated power box (20), characterized by an HV temperature control unit (14) for temperature control of a HV battery storage (52) of the vehicle,wherein the housing (22) of the power arrangement (10) also includes the HV temperature control unit (14) forming the integrated power box (20), and safety function hardware (42) for electrical protection of the AC charger (12).

Description

The present invention relates to a power arrangement for a vehicle according to the preamble of claim 1 or according to the preamble of claim 6. The increasing prevalence of electric drives in vehicle manufacturing is leading to a transformation in vehicle construction. Currently, electric vehicles are often still small-series production models, the manufacturing of which is very complex. To enable the widespread adoption of electric drives in mass-produced models with increasing production volumes, optimizations compared to existing designs are therefore necessary. Current vehicle architectures must be analyzed and optimized. To enable an electric drive, the vehicle is supplied with a high-voltage (HV) direct current (DC) supply, currently in the range of several hundred volts. Vehicles with electric drives therefore typically include an AC charger, an HV temperature control unit, a DC / DC converter, and an HV power distribution system. These HV components together form a high-voltage power arrangement. Additionally, an electric vehicle usually has an HV battery storage system for storing electrical energy. In the HV battery storage system, a number of individual battery cells are connected in series to provide HV DC voltage. A higher current can be provided by connecting such battery cell strings in parallel. If necessary, the voltage supplied by the HV battery storage system is increased to the HV DC voltage by a DC / DC converter. The aforementioned high-voltage (HV) components are currently provided individually within the vehicle; that is, each HV component has its own housing, is separately mounted in the vehicle, has its own electrical wiring and location, and includes its own cooling system with separate cooling hoses. This results in a high installation effort, high weight, and significant packaging overhead. The AC charger allows the vehicle to be connected to an external AC power supply for charging its high-voltage (HV) battery storage system. For safety reasons, modern AC chargers are equipped with an isolation transformer to provide galvanic isolation between the AC power supply and the HV DC voltage in the vehicle. This galvanic isolation protects against electric shocks and prevents DC feedback from the vehicle to the external AC power supply. This galvanic isolation requires a relatively large amount of space within the AC charger, adds considerable weight, and is typically expensive. DE 11 2016 002 239 T5 discloses a performance arrangement for a vehicle according to the preamble of claim 1 or according to the preamble of claim 6. From DE 11 2006 003 033 T5, a system and a method for the general control of power converters are known in this context. A power conversion module for a vehicle is also known from DE 10 2015 219 917 A1. The module comprises a housing and a power conversion unit installed on an inner surface of a base panel of the housing. The power conversion unit comprises a capacitor module, a power module, an inverter, and an LDC. A water-cooled cooling unit is installed on an outer surface of the base panel of the housing and is arranged in a position corresponding to the inverter's power module and the LDC, with the base panel of the housing inserted between them. An air-cooled cooling fin is installed on the outer surface of the base panel and is arranged in a position corresponding to a capacitor module, with the base panel of the housing inserted between them. Furthermore, DE 10 2014 016 076 A1 discloses a DC / DC converter for a motor vehicle comprising two high-voltage connections, a high-voltage DC / AC converter with a high-voltage converter switch, a galvanically isolated transformer, a low-voltage AC / DC converter, an intermediate circuit with an intermediate circuit capacitor, and a converter module connected to the intermediate circuit for converting an intermediate circuit voltage into a low-voltage DC voltage. The converter module includes two low-voltage connections. A control device for the high-voltage converter switch is designed to control the high-voltage converter switch with a predetermined and fixed duty cycle, such that the conversion ratio between the high-voltage DC voltage and the intermediate circuit voltage, realized via the high-voltage DC / AC converter, the transformer, and the low-voltage AC / DC converter, remains constant. Furthermore, an AC / DC converter of an energy conversion device is known from DE 10 2015 223 655 A1. This converter comprises a filter, a PFC circuit, a first full-bridge circuit, a first transformer, and a first rectifier circuit, and converts an externally supplied AC voltage into a DC voltage. A DC / DC converter comprises a filter, a second full-bridge circuit, a second transformer, and a second rectifier circuit, and reduces a DC voltage output by the AC / DC converter. Circuit components of the AC / DC converter located on the primary side of the first transformer are mounted on the upper surface of a cooling enclosure that cools both converters. Circuit components of the AC / DC converter located on the secondary side of the first transformer and circuit components of the DC / DC converter are mounted on the lower side of the cooling enclosure. DE 10 2014 217 703 A1 discloses a power arrangement for a vehicle with an AC charger for connecting to an external AC power supply and providing a high-voltage direct current for the vehicle, with a DC / DC converter for converting the high-voltage direct current into a vehicle electrical system voltage, wherein the AC charger is implemented using semiconductor technology without galvanic isolation. Temperature control devices for a vehicle are known from DE 11 2015 001 115 T5 , DE 11 2015 004 646 T5 and DE 10 2011 082 584 A1. From DE 10 2015 108 372 A1, from US 5 504 655 A and from DE 10 2006 034 020 A1, HV voltage distributions for distributing the HV DC voltage in the vehicle are known. DE 10 2006 034 020 A1 and DE 10 2007 024 567 A1 show a housing of power arrangements. Safety devices for protecting electrical components are disclosed in DE 10 2011 084 362 B4 , DE 10 2013 015 206 B3 and DE 10 2010 062 369 A1. DE 10 2016 013 490 A1 discloses further state of the art, Based on the aforementioned prior art, the invention is therefore based on the objective of specifying a power arrangement of the aforementioned type, wherein the power arrangement is efficient to manufacture, easy to assemble, has a low weight, a small form factor, generates low electrical losses and is also cost-effective to provide. The problem is solved according to the invention by the features of the independent claims. Advantageous embodiments of the invention are specified in the dependent claims. Thus, a power arrangement for a vehicle is provided with an AC charger for connecting to an external AC power supply and providing a high-voltage direct current (HV DC) voltage for the vehicle, a high-voltage temperature control unit for temperature control of a high-voltage battery storage unit of the vehicle, a DC / DC converter for converting the high-voltage direct current into a vehicle electrical system voltage, and a high-voltage distribution unit for distributing the high-voltage direct current in the vehicle, wherein the AC charger is implemented using semiconductor technology without galvanic isolation, and the power arrangement comprises a housing in which the AC charger, the high-voltage temperature control unit, the DC / DC converter, and the high-voltage distribution unit are arranged to form an integrated power box. The basic idea is to provide an integrated power box by intelligently combining high-voltage (HV) functions, offering advantages in terms of packaging, efficiency, weight, cost, and overall performance. For example, the combined arrangement of these components reduces the number of cable runs between them—the AC charger, the HV temperature control unit, the DC / DC converter, and the HV voltage distribution unit. This applies to both electrical cables and, for instance, coolant lines for cooling the individual components of the integrated power box, thus reducing cable and cooling line lengths and saving weight. Furthermore, in conventional designs, each component must be connected individually. Compared to mounting the components separately, the integrated power box can be assembled more efficiently.Further optimization of the AC charger, eliminating the need for a conventional transformer, allows for various degrees of freedom in the design of the integrated power box. Such an AC charger also boasts high efficiency. The vehicle is specifically an electric vehicle powered by an integrated power box. It can be powered exclusively by electricity or, as a hybrid vehicle, combine an electric drive with another type of drive, such as a conventional combustion engine. The AC charger connects to an external AC power supply and converts the external AC voltage into a high-voltage direct current (HV DC) voltage for use in the vehicle. In vehicles with an electric power generator, also known as a range extender, electrical energy from the range extender can also be converted via the AC charger and fed into the HV battery storage or the drive system. The AC charger is a power electronic component implemented using semiconductor technology without galvanic isolation. This allows for a lightweight AC charger and a corresponding integrated power box. The elimination of a transformer also reduces the required installation space. The AC charger can be connected to the external AC power supply via a charging cable or inductively. The high-voltage (HV) temperature control system is used to regulate the temperature of the vehicle's HV battery storage system. The HV battery storage system is typically circulated by a heat transfer fluid, which can heat and / or cool the HV battery storage system, depending on factors such as battery load, operating mode, and / or ambient conditions. For example, the HV temperature control system may include an HV heater that warms the heat transfer fluid at low temperatures. The heated fluid then flows through a battery circuit to raise the temperature of the HV battery storage system and thereby reduce its internal resistance. This allows for higher available system power. If the temperature of the HV battery storage system exceeds a certain threshold, the HV temperature control system can cool the HV battery storage system to protect the battery cells.The high-voltage (HV) temperature control unit is positioned within the integrated power box for optimal placement within the fluid circuit. Heating elements used in the HV heater include, for example, heating stones or a surface resistor. The surface resistor is positioned over a large area within the integrated power box to ensure maximum heat transfer into the battery circuit via a special thermally conductive material. The HV temperature control unit is equipped with semiconductor switching elements for operation. The DC / DC converter transforms the high-voltage direct current (HV DC) into the vehicle's electrical system voltage. The DC / DC converter transforms the HV DC voltage, as supplied by the vehicle's AC charger or HV battery storage system for propulsion, into the vehicle's electrical system voltage. The HV DC voltage can be, for example, approximately 800V. The vehicle's electrical system voltage is typically 12V, but can also be 24V or 48V. The DC / DC converter is preferably implemented as a power electronic component using semiconductor technology, for example, as a step-up or step-down converter, or as a boost converter. The high-voltage (HV) power distribution system enables the distribution of high-voltage direct current (HV DC) within the vehicle. In principle, any HV load can be supplied with HV DC via the HV power distribution system. In particular, the vehicle's electric drive system is connected to the HV power distribution system. The HV power distribution system typically includes multiple busbars and switching devices for connecting or disconnecting individual branches. To facilitate maintenance and / or repair, the HV power distribution system is positioned in an upper section of the integrated power box, making it easily accessible from above when installed in the vehicle's engine compartment. The housing is designed as a common enclosure for all components, i.e., it includes the AC charger, the high-voltage temperature control unit, the DC / DC converter, and the high-voltage distribution unit. Additionally, a common connection to a cooling system can be provided via the housing. The housing is preferably made of lightweight materials. Such lightweight materials include, for example, plastics or light metals such as aluminum, with plastics or other electrically non-conductive materials being preferred. By designing the power arrangement as an integrated power box, a single cooling unit can, for example, cool all the components within the power box simultaneously. The cooling unit dissipates heat generated by the resistance of the electrical components and their connections, preventing damage from overheating and reducing ohmic resistance by lowering the temperature. According to claim 1, the power arrangement includes safety function hardware for the electrical protection of the AC charger. Preferably, the safety function hardware is an integral part of the AC charger. In the event of a fault, the safety function hardware becomes active to protect the vehicle. In particular, the safety function hardware is designed and arranged to disconnect the AC charger from the external AC power supply in the event of a fault. The safety function hardware typically comprises a plurality of switching elements. The switching elements can be electromechanical, for example as contactors, or purely electronic with power semiconductors. An embodiment with power semiconductors is preferred. In an advantageous embodiment, the power arrangement includes a safety device for disconnecting the DC / DC converter. Preferably, the safety device is an integral part of the DC / DC converter. The safety device activates in the event of a fault to protect the vehicle. In particular, the safety device is designed and arranged to disconnect the DC / DC converter in the event of a fault. The safety device typically comprises multiple switching elements. These switching elements can be electromechanical, for example, as contactors, or purely electronic using power semiconductors. An embodiment using power semiconductors is preferred. In an advantageous embodiment, the power arrangement includes a switching device for switching the high-voltage distribution. Preferably, the switching device is an integral part of the high-voltage distribution. The switching device typically comprises a plurality of switching elements. The switching elements can be electromechanical, for example as contactors, or purely electronic with power semiconductors. An embodiment with power semiconductors is preferred. In an advantageous embodiment, the power arrangement has a modular design with at least two modules, in particular one module each for the AC charger, the high-voltage temperature control unit, the DC / DC converter, and the high-voltage distribution unit. The modular design allows for the easy provision of various integrated power boxes by selecting individual modules as needed and combining them to form the integrated power box. A modular design also facilitates the replacement of individual modules in the event of a failure or damage. The modules can be selected and combined not only according to their electrical function but also taking into account their size and mechanical requirements. This allows for the use of different vehicle platforms. A sufficient sealing concept between the modules is important to ensure the safety of the components they contain. According to claim 6, the housing is designed as a crash-relevant structure for stabilizing the vehicle, in particular as a stabilizing strut for at least a few of the vehicle's strut towers. The integrated power box can thus, in addition to its electrical function, form a structural component that enhances the vehicle's stability. For example, a suitably designed housing can eliminate the need for one or more strut tower braces in the front of the vehicle to stabilize the overall vehicle. Accordingly, the integrated power box can, for instance, be mounted between two front strut towers, with a mounting bracket being screwed from each front strut tower to the integrated power box. The integrated power box can therefore assume the function of one or more strut tower braces. In an advantageous embodiment, the housing has at least one service hatch that allows access to replaceable components of the power arrangement. Such replaceable components are, in particular, fuses, enabling easy replacement in the event of a fault. The fuses are, in particular, high-voltage fuses, for example, for protecting the AC charger. Preferably, the integrated power box also includes an evaluation circuit that monitors and, if necessary, reports the correct installation of the fuses and / or the opening of the service hatch. Furthermore, the electronics of a module can also be completely replaceable via a service hatch. In an advantageous embodiment, internal electrical connections between the AC charger, the HV temperature control unit, the DC / DC converter, and the HV voltage distribution are implemented using a "blade" technology. In blade technology, an electrical connection comprises a blade and a Faston connector. During the establishment of the electrical connection, the blade plunges into the Faston connector and makes contact using friction and pressure. The blade technology is designed to allow the connection between the blade and the Faston connector to be established and closed multiple times. In an advantageous embodiment of the invention, the power arrangement has an internal communication link that connects the AC charger, the high-voltage temperature control unit, the DC / DC converter, and the high-voltage distribution system. This communication link can be based, for example, on an internal communication bus commonly used in the automotive sector, such as CAN, SPI, LIN, or Ethernet. Preferably, the communication link is shielded against electromagnetic interference to meet electromagnetic compatibility (EMC) requirements. The invention is explained below by way of example with reference to the accompanying drawings and preferred embodiments, wherein the features shown below can represent an aspect of the invention both individually and in combination. Figure 1 shows a perspective view of a power arrangement according to a first, preferred embodiment with an AC charger, an HV temperature control device, a DC / DC converter and an HV voltage distribution, which are arranged in a common housing to form an integrated power box; Figure 2 shows a schematic representation of the AC charger from Figure 1 with an input filter, a rectifier, a power factor correction filter, a smoothing element, a DC / DC converter and an output filter; and Figure 3 shows a functional, schematic representation of the AC charger from Figure 2 with an additionally shown current monitoring device and a further shown shutdown device. Fig. 1 shows a power arrangement 10 according to the invention for a vehicle according to a first, preferred embodiment. The vehicle of the first embodiment is an electric vehicle with an electric drive which is supplied with electrical energy via the power arrangement 10. The power arrangement 10 comprises an AC charger 12, an HV temperature control unit 14, a DC / DC converter 16, and an HV voltage distribution unit 18, which are arranged in a common housing 22 to form an integrated power box 20. Internal electrical connections between the AC charger 12, the HV temperature control unit 14, the DC / DC converter 16, and the HV voltage distribution unit 18 are implemented using blade technology. The AC charger 12 is used to connect to an external AC power supply 38 and to convert the AC voltage supplied by it into a high-voltage direct current (HV) voltage 40, which is provided in the vehicle. The AC charger 12 is designed as a power electronic element using semiconductor technology without galvanic isolation. The AC charger 12 is connected to the external AC power supply 38 via a charging cable. The AC charger 12 of the first embodiment is shown in detail in Figures 2 and 3. The illustration in Figure 2 is based on a functional structure as used in AC chargers 12 known per se. Accordingly, the AC charger 12 comprises as functional components an input filter 24, a rectifier 26 with a plurality of semiconductor switching elements 28, a power factor correction filter 30, a smoothing element 32, a DC-DC converter 34, and an output filter 36, which are connected in series in this order. On the input side, the AC charger 12 is connected to the AC voltage supply 38 and delivers the high-voltage DC voltage 40 on the output side. The AC charger 12 additionally includes safety function hardware 42 for the electrical protection of the AC charger 12, which is shown in Fig. 3. In the event of a fault, the safety function hardware 42 disconnects the AC charger 12 from the external AC power supply 38. For this purpose, the safety function hardware 42 includes a disconnecting device 44 with a plurality of switching elements (not shown individually) which interrupt the connection to the AC power supply 38 when activated. The switching elements are electronically implemented with power semiconductors. The safety function hardware 42 also includes a differential current monitor 46, which monitors differential currents in the three phases I1, I2, I3 and the neutral conductor N of the external AC power supply 38. The safety function hardware 42 further includes a compensation device 48. A monitoring device 50 receives differential currents measured in the differential current monitor 46 to identify faults. In the event of a fault, the current monitoring device 50 controls the disconnecting device 44 to disconnect the AC charger 12 from the external AC power supply 38, or the compensation device 48 to perform current compensation. Additionally, the monitoring device 50 also controls the DC / DC converter 34, for example, to deactivate the DC / DC converter 34 in the event of a fault in the AC charger 12. As shown in Fig. 3, the AC charger 12, in accordance with the descriptions in Fig. 2, includes an input filter 24, which is referred to here as the EMC filter. The DC-DC converter 34, together with the power factor correction filter 30, is connected downstream of the input filter 24. The DC-DC converter 34 and the power factor correction filter 30 are integrated in this representation. The output filter 36 is also connected downstream in this illustration. On the output side, the HV DC voltage 40 provided in this way is connected to an HV battery storage system 52. The HV temperature control unit 14, the DC / DC converter 16, and the HV voltage distribution unit 18 are also connected to the HV DC voltage 40. The high-voltage (HV) temperature control unit 14 serves to regulate the temperature of the vehicle's HV battery storage unit 52. Here, the HV temperature control unit 14 is implemented as an HV heater 14. A heat transfer fluid flows through the HV battery storage unit 52 to heat it. The HV heater 14 heats the heat transfer fluid. The HV temperature control unit 14 is equipped with semiconductor switching elements for control. The DC / DC converter 16 converts the high-voltage direct current (HV DC) voltage 40, as supplied by the vehicle's AC charger 12 or HV battery storage 52, to the vehicle's electrical system voltage. Here, the HV DC voltage 40 has a value of 800 V, and the electrical system voltage is 12 V. In an alternative embodiment, the electrical system voltage is 24 V or 48 V. The DC / DC converter 16 is implemented as a power electronic component using semiconductor technology. Furthermore, the DC / DC converter 16 includes a safety device for disconnecting the DC / DC converter 16. The safety device is designed and configured to disconnect the DC / DC converter 16 in the event of a fault. The safety device typically comprises multiple switching elements. These switching elements are implemented electronically using power semiconductors. The high-voltage distribution unit 18 distributes the high-voltage DC voltage 40 within the vehicle. Consumers in the vehicle are supplied with the high-voltage DC voltage 40 via the high-voltage distribution unit 18. This applies in particular to the vehicle's electric drive system. The high-voltage distribution unit 18 is positioned in an upper area of ​​the housing 22. The high-voltage distribution unit 18 comprises several busbars and a switching device for connecting or disconnecting individual supply branches. The switching device is equipped with individual switching elements that are electronically implemented with power semiconductors. The power arrangement 10 includes an internal communication link (not shown here) that connects the AC charger 12, the HV temperature control unit 14, the DC / DC converter 16, and the HV voltage distribution unit 18. The internal communication link can be connected to a control device of the vehicle via an interface formed on the housing 22. The housing 22 serves as a common enclosure for all components 12, 14, 16, and 18, in which the AC charger 12, the HV temperature control unit 14, the DC / DC converter 16, and the HV voltage distribution unit 18 are arranged. The integrated power box 10 is connected to a cooling system via the housing 22. The housing 22 is made of plastic. It features a service hatch that provides access to replaceable components of the power assembly 10. The housing 22 is designed as a crash-relevant structure for stabilizing the vehicle. The power assembly 10, when installed, is mounted within the housing 22 as a stabilizing strut, also known as a strut brace, between two front strut towers of the vehicle. For this purpose, a mounting bracket is screwed from each front strut tower to the integrated power box 20. The power arrangement 10 of the first embodiment has a modular design, wherein the AC charger 12, the HV temperature control unit 14, the DC / DC converter 16 and the HV voltage distribution unit 18 are each designed as individual modules and connected to the integrated power box 20. The individual modules are sealed against each other to seal the housing 22 as a whole.

Claims

Power arrangement (10) for a vehicle, comprising an AC charger (12) for connecting to an external AC power supply (38) and providing a high-voltage direct current (HV DC) voltage (40) for the vehicle, a DC / DC converter (16) for converting the HV DC voltage (40) into a vehicle electrical system voltage, and an HV voltage distribution unit (18) for distributing the HV DC voltage (40) in the vehicle, wherein the AC charger (12) is implemented using semiconductor technology without galvanic isolation, and wherein the power arrangement (10) comprises a housing (22) in which the AC charger (12), the HV temperature control unit (14), the DC / DC converter (16), and the HV voltage distribution unit (18) are arranged to form an integrated power box (20), characterized by an HV temperature control unit (14) for temperature control of a HV battery storage (52) of the vehicle,wherein the housing (22) of the power arrangement (10) also includes the HV temperature control unit (14) forming the integrated power box (20), and safety function hardware (42) for electrical protection of the AC charger (12). Power arrangement (10) according to claim 1, characterized in that the power arrangement (10) has a safety device for disconnecting the DC / DC converter (16). Power arrangement (10) according to one of the preceding claims, characterized in that the power arrangement (10) has a switching device for switching the HV voltage distribution (18). Power arrangement (10) according to one of the preceding claims, characterized in that the power arrangement (10) has a modular structure with at least two modules. Power arrangement (10) according to claim 4, characterized in that the power arrangement (10) comprises a module for the AC charger (12), the HV temperature control device (14), the DC / DC converter (16) and the HV voltage distribution (18). Power arrangement (10) for a vehicle, comprising an AC charger (12) for connecting to an external AC power supply (38) and providing a high-voltage direct current (HV DC) voltage (40) for the vehicle, a DC / DC converter (16) for converting the HV DC voltage (40) into a vehicle electrical system voltage, and an HV voltage distribution unit (18) for distributing the HV DC voltage (40) in the vehicle, wherein the AC charger (12) is implemented using semiconductor technology without galvanic isolation, and wherein the power arrangement (10) comprises a housing (22) in which the AC charger (12), the HV temperature control unit (14), the DC / DC converter (16), and the HV voltage distribution unit (18) are arranged to form an integrated power box (20), characterized by an HV temperature control unit (14) for temperature control of a HV battery storage (52) of the vehicle,wherein the HV temperature control unit (14) is also arranged in the housing (22) of the power arrangement (10) forming the integrated power box (20), the housing (22) being designed as a crash-relevant structure for stabilizing the vehicle. Performance arrangement (10) according to one of the preceding claims, characterized in that the housing (22) serves as a stabilizing strut for at least a few vehicle domes. Power arrangement (10) according to one of the preceding claims, characterized in that the housing (22) has at least one service flap which allows access to replaceable components of the power arrangement (10). Power arrangement (10) according to one of the preceding claims, characterized in that internal electrical connections between the AC charger (12), the HV temperature control unit (14), the DC / DC converter (16) and the HV voltage distribution (18) are implemented according to a “blade” technology. Power arrangement (10) according to one of the preceding claims, characterized in that the power arrangement (10) has an internal communication link connecting the AC charger (12), the HV temperature control unit (14), the DC / DC converter (16) and the HV voltage distribution unit (18).

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