DE102020210108A1 - Power distribution unit for a mobile work machine and mobile work machine with the power distribution unit - Google Patents

Abstract

Disclosed is a power distribution unit for a mobile working machine for distributing electrical energy from a voltage source of the working machine to its electrified functions, in particular drive, work, protection, protection, charging and/or energy storage functions, with a housing in which the functions associated functional assemblies are electrically contacted. Also disclosed is a mobile working machine with the power distribution unit.

Description

The invention relates to a power distribution unit for a mobile machine according to the preamble of patent claim 1, and a mobile machine with it according to patent claim 15.

Power Distribution Units (PDUs) are used to distribute electrical energy in vehicles. In the case of electrically powered vehicles, these are also high-voltage voltages (HV). Nowadays these go up to 800V DC. In addition to distributing electrical energy, PDUs often perform other functions, such as protecting the DC connections against overcurrent, switching off DC connections using high-voltage contactors, insulation monitoring and reporting of insulation faults, as well as communication and sensor technology tasks and the like. Depending on the application, the structure, the range of functions and the implementation of the PDUs for HV applications are very different.

In the automotive sector, the trend towards increased integration of various functions in a subsystem assembly has become increasingly noticeable in recent years. The PDU is also included here. Representative of this progressive integration is the development of the Nissan Leaf from its first generation in 2010 to the generation of 2017. The inverter, electric motor, gearbox and PDU are integrated into a compact unit.

This increase in integration is useful in the automotive or motor vehicle sector, as it reduces the number of plug connections, the number of cables required, the installation work and the installation space occupied by the PDU, which offers a price advantage and enables a more compact design. Large quantities in the automotive sector justify the increased development effort for such highly integrated solutions.

In the case of mobile work machines or in the off-highway area, on the other hand, the achievable quantities per vehicle are significantly lower and a greater variety of variants is usually required. The number of drives required and the power of the drives vary greatly from application to application and from machine size to machine size. If inexpensive standard PDUs are then used, these are either oversized or undersized for the specific application. A standard PDU is, for example, a PDU that is already available on the market, for example that of a predecessor of the mobile working machine. If, on the other hand, a custom-made PDU is selected, this entails a high level of engineering effort, which is associated with higher costs and a longer development time. This results in an unfavorable ratio of development and validation costs to the turnover that can be achieved with the machine.

In contrast, the invention is based on the object of creating a power distribution unit for a mobile machine with electrified functions, which is designed to meet requirements with less effort, and to create a mobile machine that can be configured with less effort with regard to its electrified functions with regard to energy distribution .

These objects are achieved by a power distribution unit having the features of patent claim 1 and a mobile working machine having the features of patent claim 15.

Advantageous developments of the power distribution unit are described in patent claims 2 to 14.

A power distribution unit for a mobile working machine is used to distribute electrical energy from a voltage source of the working machine to its electrified functions, in particular drive, work, protection, protection, charging and/or energy storage functions. The voltage source can be, for example, a battery or a DC charger coupled to a generator or the like. The power distribution unit has a housing that is protected, in particular according to IP69 or IP6K9K, in which electrical and/or electronic functional assemblies assigned to the functions are electrically contacted. According to the invention, the functional assemblies are each part of a module. This is attached to the housing as one part, ie with little assembly and disassembly effort, and is contacted in the housing. This contacting establishes contact with the functional assembly.

Due to the modular design, a power distribution unit is created with function-specific functional assemblies that are easy to attach and contact because they are modular. As a result, the power distribution unit can be configured more flexibly and with less effort for a specific working machine, which particularly affects the adaptation to the number, current carrying capacity, range of functions (e.g. load disconnectors) of the modules and the integration of additional functional assemblies.

The following functions of the working machine should be mentioned in particular: inverters, high-voltage batteries, on-board chargers, DC/DC converters, DC charging, all in different performance classes, as well as insulation monitors (Insulation Monitoring Device - IMD) or communication and sensor units.

The function of the power distribution unit is to connect it to the electrical energy source. The following functions of the power distribution unit are particularly worth mentioning: Connection of inverter, connection of high-voltage batteries, connection of on-board charger, connection of DC/DC converter, DC charging option, all in different power classes, and insulation monitor (Insulation Monitoring Device - IMD ) or communication and sensor units.

The following functional assemblies should be mentioned in particular: protection of current paths to reduce the cross-section of connected cables using fuses of various sizes and characteristics, capacitances to stabilize an electrical intermediate circuit in the housing, filter elements, for example EMC filters, contactors to switch off individual current paths, current measuring devices, voltage measuring devices, insulation measuring devices, Control units, such as charging controllers, conductive structures or current paths without additional functions.

In a further development, the modules are detachably fastened in a non-destructive manner. Changing the modules, for example to adapt to a changed function of the working machine or for maintenance or repair, can thus be carried out even more easily.

In a further development, functional modules are combined into one of the modules, which often occurs in combination with functions, which simplifies and accelerates assembly or changing of the combined functional modules.

The modules correspond to module slots on the housing side, in short slots to which the modules are attached and contacted. At least two, preferably more, in particular a number of places adapted to the range of functions of the work machine are provided.

In a further development, at least one of the places is kept unoccupied, ie no module is arranged there. In this way, future viability of the power distribution unit is ensured in a simple manner, since further modules for further functions can be subsequently added to the vacant place or places. In addition, if a module is defective, it can be easily replaced with less downtime or no downtime at all. Furthermore, it is also conceivable to enable an upgrade functionality by exchanging modules, which represents a retrofit in the life cycle of a vehicle, for example.

In a further development, the modules are the same and/or the places are the same. It is particularly advantageous for them to have a standardized design. Function-specific features of the modules and/or places may be an exception to this. In this way, a power distribution unit based on the needs of the working machine can be provided in a modular manner and with particularly little effort from modules and/or locations of the housing that are essentially the same or standardized. Under- or over-dimensioning is thus prevented with even less effort and the engineering effort is minimized. An additional advantage is that an arrangement or sequence of the modules can be varied very easily through equality and/or standardization. However, it should be noted here that due to the current carrying capacity, certain arrangements/sequences of the modules are to be preferred when integrating them into the housing.

The previously described disadvantageous effect of low unit numbers of the working machine is thus eliminated. The advantage of high quantities can thus be exploited at the module level but also at the housing level.

These advantages are reinforced if, in a further development, the modules, with or without a functional assembly, and/or the housing, in particular its locations, are each removed and tested for standardization.

These advantages are reinforced if, in a development, attachment interfaces and/or contact interfaces of the modules in the housing and/or the places are the same and/or are standardized.

These advantages are reinforced if, in a further development, the modules and/or the spaces have the same main dimensions as one another.

In addition, modules and spaces tailored to them can be provided that have a multiple of these main dimensions. The main dimensions are in particular a width and height of the module and the corresponding width and height of its place or a mounting opening or a panel or front panel of the module or a cutout in the housing that is covered by the panel or front panel.

In particular, the cutout is dimensioned such that it is a mounting opening for the module. This enables very simple and quick assembly and disassembly of the module.

Equality and/or standardization is easily implemented with a development in which the modules each have a carrier on which the functional assembly is arranged and contacted by conductor tracks of the carrier. The carrier consists in particular of a non-conductive material on which conductive structures for contacting the functional assembly are applied. The conductive structures represent the current paths of the DC connections, for example, and can be located on the top or bottom of the non-conductive material. In particular, the carrier is designed as a printed circuit board or printed circuit board (PCB). The use of a different technology, such as a simple plastic plate with current paths, is of course possible. The carrier can be placed in the housing lying down, ie with one surface horizontal, or standing up, with a main surface vertical.

A particularly uncomplicated contacting of the modules in the housing, and thus of the functional assemblies, is implemented in a development that has at least one busbar in the housing. In particular, a plus or ground rail is provided. Preferably both are provided. In this way, the modules are contacted and connected via an intermediate circuit, in particular a DC circuit.

The busbar or busbars can be arranged on the housing side or on the module side or distributed over these.

In one development, the at least one busbar extends along the locations continuously or, in particular in sections, from module to module, so that sections of the busbar are formed by the modules.

In a development, the busbar extends along one side of the housing, in particular in a straight line. This enables clear and simple contacting.

In a further development, the contacting of the module in the housing, and thus of the functional assembly, in particular of the busbar, takes place via a spring or clamp mount or via screw connections. The latter are based in particular on press-in elements with a thread. The spring or clamp mount or the press-in elements and screw connections can be arranged on the module or, alternatively, on the sites.

The module preferably has one contact per busbar.

In a further development, the seats are arranged in one or more rows next to and/or on top of one another.

In one development, the respective space has at least one cutout in one side of the housing and a space section in the housing to the rear of the cutout. The cutouts preferably all have the same cross section, diameter, width and/or height. The space sections are also preferably the same in terms of their volume, length, width and/or height.

The module preferably penetrates or grips the cutout.

In a development, a panel or front panel of the module covers and/or closes the cutout.

In a further development, sections of unoccupied spaces are closed off by a plate, in particular a plate without a plug.

A sealant is preferably arranged between the plate and the side of the housing, via which the cutout is sealed, in particular according to an IP69 or IP6K9K standard that meets the requirements, in particular the high-quality IP69 or IP6K9K standard that is preferred for dirt-loaded outdoor applications.

In a further development, an electrical interface of the functional module towards the function is arranged on the front panel, in particular in the form of a plug or a screw plug or a cable gland or the like. These "external" electrical interfaces are function-specific, i.e. they are usually different from one another, but are preferably standardized.

A mobile working machine has a power distribution unit that is configured in accordance with at least one aspect of the preceding description. It also has an electrical voltage source as the energy source, which is connected to the module of a functional assembly of the power distribution unit that is assigned to it. In addition, it has at least two functions to which power is to be distributed. These are propulsion, work, protection, protection, and/or energy storage functions. These are also connected to the module of the functional assembly of the power distribution unit assigned to them.

The mobile work machine is, for example, a municipal vehicle, wheel loader, excavator, telehandler, handling loader for containers, or the like.

The design of the power distribution unit according to the invention and its use in the mobile machine solves the problems discussed above, which result from the small number of units and the high variety of mobile machines, or the "off-highway" mobility. A mobile work machine is thus created which can be configured with less effort in terms of its electrified functions.

Apart from the work machines mentioned, or “off-highway” mobility, further uses of the invention are conceivable. The focus here is primarily on vehicles that are manufactured in small numbers and also require a high degree of flexibility.

• 1 zwei Ausführungsbeispiele eines Gehäuses einer Stromverteilereinheit mit drei und mit fünf Plätzen in perspektivischer Ansicht,
• 2 ein Ausführungsbeispiel eines Moduls der Stromverteilereinheiten gemäß 1 in perspektivischer Ansicht,
• 3 ein Ausführungsbeispiel einer Frontplatte mit Stecker des Moduls gemäß 2 in einer Vorder-, einer Schnitt- und einer Detailansicht,
• 4 zwei Ausführungsbeispiele eines Gehäuses einer Stromverteilereinheit mit elektrischem Zwischenkreis mit einmal vier und einmal sechs Plätzen, in transparenter Draufsicht,
• 5 ein Ausführungsbeispiel einer Stromverteilereinheit mit dem Gehäuse gemäß 4 mit vier Plätzen, und mit montierten Modulen mit Frontplatten,
• 6 drei Ausführungsbeispiele von mit Funktionsbaugruppen bestückten Modulen in einer Draufsicht,
• 7 drei Ausführungsbeispiele von Kontaktierungen von Modulen im Zwischenkreis mittels Verschraubungen, und
• 8 ein Ausführungsbeispiel einer Kontaktierung eines Moduls im Zwischenkreis mittels Federkontaktierung.

In the following, exemplary embodiments of a power distribution unit according to the invention for a mobile working machine, and a mobile working machine with it, are explained in more detail with reference to figures. Show it:

• 1 two exemplary embodiments of a housing for a power distribution unit with three and five places in a perspective view,
• 2 an embodiment of a module of the power distribution units according to 1 in perspective view,
• 3 an embodiment of a front panel with connector of the module according to 2 in a front, a sectional and a detail view,
• 4 two exemplary embodiments of a housing for a power distribution unit with an electrical intermediate circuit with one for four and one for six places, in a transparent top view,
• 5 an embodiment of a power distribution unit with the housing according to 4 with four places, and with mounted modules with front panels,
• 6 three exemplary embodiments of modules equipped with functional assemblies in a plan view,
• 7 three exemplary embodiments of contacting modules in the intermediate circuit using screw connections, and
• 8th an exemplary embodiment of contacting a module in the intermediate circuit by means of spring contacts.

According to 1 is a housing 2; 102 of a power distribution unit 1; 101 with for modules (these are shown as an example 2 , 6 , 7 , 8th ) provided places 4 realized. The modular design results in different lengths of the housing 2; 102 depending on the number of necessary places 4 in order to be able to accommodate different numbers of modules depending on the needs of the working machine. In 1 the housing 2 with four spaces 4 for modules is shown on the left, and the housing 102 with six spaces 4 for modules is shown on the right. Each seat 4 has the same main dimensions of width B, height H and depth T. Thus, each expression of a standardized module on any place 4 within the housing 2; 102 can be mounted. The assembly of a module in the housing 2; 102 can be horizontal (lying) or vertical (standing). The housing 2; 102 has at each seat 4 in its front side a cutout 5, which is rectangular in the exemplary embodiments shown. It is dimensioned in width B and height H in such a way that the module passes through it into the housing 2; 102 can be used.

2 shows an embodiment of a standardized module 6, which can be used in the housing of all shown embodiments at the 4 places. It has a carrier 8 on which at least one area 10 for variable assembly with a function-specific functional module and at least one electrical interface 12 for contacting in the housing, in particular a DC intermediate circuit, is provided. At the front, the module 6 has a plate or front plate 14 which is normal to the carrier 8. This is continuous or has a sealable area 16 for arranging an externally pointing electrical interface of the module, for example a plug, for contacting the electrified function. For the sake of simplicity, the front panel 14 and the carrier 8 are designed to be rectangular and planar, but they can also have shapes or cross-sections that deviate from this.

A challenge for the case 2; 102; 202; 302 represent the electrical interfaces of the individual modules 4 to the outside, to the functions, regardless of the exemplary embodiment. These are designed in accordance with the requirements for the degree of protection for the off-highway area, in particular according to the IP69 or IP6K9K standard. Nevertheless, the flexibility of the modular construction method must be maintained.

A solution to this is the use of standardized cutouts 5 in the respective housing 2; 102; 202; 302, with the same main dimensions B and H already mentioned. These 5 are then closed by the corresponding, likewise standardized front panels 14 of the modules 6. The excerpts 5 are identical for each square 4.

3 shows this interaction of section 5 and front panel 14. It is in 3 on the left a front view with a cut definition AA, the section along AA is shown in the middle and a detail of section AA is shown on the right. A seal 20 is arranged between the front panel 14 and the housing 2, so that the housing meets the IP69 or IP6K9K standard. The front panel 14 is fastened to the housing 2 with screws 22 as possible fastening means, as a result of which the entire module 6 is mechanically fastened to the housing 2 . The drilling pattern of the screws 22 around the section 4 and in the front panel 14 is the same for all sections 5 and front panels 14 . Such identical or standardized mechanical fastening points between the module 6 and the housing 2 make it possible to arrange the modules 6 in all 4 places.

4 shows two further embodiments of housings 202; 302 in a plan view. The display is transparent and thus allows a glimpse into the interior. In this case, two busbars 24, 26 of a DC high-voltage intermediate circuit (DC+, DC-) extend for electrical contacting and connection of the modules 6 in the housing 202; 302 continuous along its broadside. The design with such continuous busbars is not limited to these exemplary embodiments.

5 shows an example of the front view of an integration of four modules 6 in the housing 202 according to FIG 4 with four module spaces 4, with each having a different external electrical interface 18, so a different connector due to the different functional assembly of the modules 6. From left to right, the interfaces are a large two-pin connector, a small four-pin connector, and a small two-pin connector. The right base plate 14 is continuous and has no interface. This position 4 is therefore not occupied by a module.

The respective electrical interface, in the form of a plug connector or a cable gland, is preferably installed in a sealed manner in the front panel.

The front panel can be screwed and/or bonded to the housing, in particular glued or welded. A non-destructively releasable connection is generally preferred, so that the advantages in terms of flexibility, replacement, maintenance, repair and the like of the modules come into play.

The front panel can be mechanically and/or cohesively attached to the carrier and the electrical interface can be mechanically and/or cohesively attached to the front panel.

6 shows an example of two individual modules 6 for the functions of an inverter (left) and the function of DC charging (DC charging) (middle). Current paths 28, 30 applied to the carrier represent the electrical interfaces of the modules 6 to the busbars 24, 26. The respective poles of the external electrical interfaces 18 are connected to the busbars 24, 26 via the current paths 28, 30 on the carriers 8 . As a special feature, the left module 6 has a fuse 32 in the positive current path 28 and the module for implementing the DC charging function has DC contactors 34 (disconnecting devices) in both current paths 28, 30. The modules 6 have the same width b and depth t.

6 on the right shows an exemplary embodiment of a module 6 in which the two aforementioned modules and a module assigned to a voltage source are combined to form a module 6, which then has three times the width 3×b. This module 6 also has the depth t.

In order to enable the core function of the power distribution unit 1, namely the distribution of the electrical energy to the functions that can be connected to the electrical interfaces 18, the individual modules 6 in the housing 2; 102; 202; 302 to be electrically connected to the DC intermediate circuit 24, 26.

For this purpose, according to 7 the three modules 6 of three exemplary embodiments, in particular their current paths 28, 30, are connected to the busbars 24, 26. The electrical interfaces 36 required for this in the housing can be realized, for example, by means of press-in elements with or without a thread or by screw connections.

In 7 on the left the busbars 24, 26 are designed in sections 24', 26' from module 6 to module 6 and connected to sections 24", 26" on the carriers 8 of the modules 6 by means of press-in elements with a thread and a screw connection.

In the embodiments according to 7 In the middle and on the right, however, the busbars 24, 26 are continuous, realized once on the upper side (central exemplary embodiment) and once on the lower side (right exemplary embodiment) of the carrier 8.

Alternatively or in addition, these electrical interfaces 36 are conceivable, for example, as plug-in connections with a clamping or clamping principle of action, what 8th shows, wherein the carrier 8 is inserted with its current paths 28, 30 in each case a corresponding clamp receptacle of the interface 36.

In addition, the arrangement or the course of the busbars 24, 26 can be variable, in particular the row of the modules 6 (single-level, multi-level) and the installation position of the carrier 8 (standing, lying) deviating from that shown, for example meandering or the like. The connection technology shown for the internal interfaces is of course not limited to what is shown.

The electrical interfaces in the housing preferably have at least one intermediate circuit current path.

In a further development, additional discrete signals, e.g. for controlling a contactor or signals from an HVIL (High Voltage Interlock) or communication signals (e.g. CAN) can be transferred to neighboring modules via the electrical interfaces in the housing.

The intermediate circuit current path can be contacted via busbars.

The busbars can run from girder to girder or across the entire width of the girder.

The supports can have a through-hole through which a screw is screwed into a threaded hole in the busbar.

Alternatively, a threaded fastener is secured to the support onto which the bus bar is bolted.

The discrete, HVIL, or communication signals can be passed through lengths of cable or connectors.

Disclosed is a power distribution unit for a mobile working machine for distributing electrical energy from a voltage source of the working machine to its electrified functions, in particular drive, work, protection, protection, charging and/or energy storage functions, the functional modules assigned to the functions being modular, are standardized and in particular detachably fastened and contacted on a carrier or in a housing of the power distribution unit. Also disclosed is a mobile working machine with it.

Reference List

1

power distribution unit

2; 102; 202; 302

casing

4

place

5

cutout

6

module

8th

carrier

10

Functional assembly area

12

internal electrical interface

14

plate

16

External interface area

18

Interface external

20

poetry

22

Module/housing fasteners

24

Busbar Plus

24'

Busbar section Plus

24"

current path plus

26

busbar mass

26'

Busbar section ground

26"

circuit ground

28

current path plus

30

circuit ground

32

fuse

34

contactor/disconnector

36

electrical interface

Claims (15)

Power distribution unit for a mobile working machine for distributing electrical energy from a voltage source of the working machine to its electrified functions, in particular drive, work, protection, protection, charging and/or energy storage functions, with a housing (2; 102; 202; 302) in which the functional assemblies (28, 30, 32, 34) assigned to the functions are electrically contacted, characterized in that the functional assemblies (28, 30, 32, 34) are each part of a module (6) which is attached to the housing ( 22) and is contacted (36) in the housing (2; 102; 202; 302). power distribution unit claim 1 with housing-side places (4) to which the modules (6) are fastened (22) and contacted (36). power distribution unit claim 2 , wherein at least one of the seats (4) is kept unoccupied. Power distribution unit at least after claim 1 or 2 , wherein the modules (6) and/or the spaces (4) are identical to one another and/or are standardized, in particular apart from function-specific features. Power distribution unit at least after claim 1 or 2 , wherein attachment interfaces (22) and / or contact interfaces (36) of the modules (6) with each other and / or the places (4) are the same with each other, and / or are standardized, in particular apart from function-specific features. Power distribution unit at least after claim 1 or 2 , wherein the modules (6) to one another and/or the spaces (4) have the same main dimensions (h, b, t, H, B, T) to one another. Power distribution unit according to one of the preceding claims, wherein the modules (6) each have a carrier (8) on which the functional assembly (28, 30, 32, 34) is arranged and/or is contacted by conductor tracks or current paths (28, 30). power distribution unit claim 7 , wherein the carrier (8) is designed as a printed circuit board. Power distribution unit according to one with at least one busbar (24, 26; 24', 26'), in particular a positive (DC+) or ground busbar (DC-), from which the modules (6) in the housing (2; 102; 202; 302 ) are contacted. Power distribution unit at least after claim 2 and 9 , wherein the at least one busbar extends continuously (24, 26) along the spaces (4), or wherein the at least one busbar extends from space (4) to space (4) with sections (24', 26') which are connected via current paths (24", 26") of the modules (6). power distribution unit claim 9 or 10 , wherein the modules (6) are electrically connected to the at least one busbar (24, 26; 24', 26') via a spring or clamp receptacle (36) or via screw connections (36). Power distribution unit at least after claim 2 , wherein the places (4) each have at least a cut-out (5) in a side of the housing (2; 102; 202; 302) and a space section in the housing (2; 102; 202; 302) behind the cut-out (5). . Power distribution unit according to 12, wherein the respective module (6) passes through the cutout (5) and has a front panel (14) from which the cutout (5) is covered. Power distribution unit according to 13, wherein an electrical interface (16, 18) of the functional assembly (28, 30, 32, 34) towards the function is arranged on the front panel (14). Mobile working machine with a power distribution unit (1), which is designed according to at least one of the preceding claims, and with a voltage source as the energy source function, which is connected to the module (6) of a functional assembly of the power distribution unit (1) assigned to it, and with at least two electrified Drive, work, protection, protection, charging and/or energy storage functions that are connected to the module (6) of a functional assembly of the power distribution unit (1) that is assigned to them.

Images