Control unit with zone concept

Abstract

Control unit (1) for an electrically powered motor vehicle, with a housing (2) that separates an outer zone (3) located outside the housing (2) from inner zones (4, 5, 6) located inside the housing (2), wherein in a first inner zone (4) lines (7), in a second inner zone (5) filters (8) and in a third inner zone (6) a logic board (9), a power board (10) and an inverter (11) are arranged, and the outer zone (3) is separated from the inner zones (4, 5, 6) and the inner zones (4, 5, 6) are separated from each other by at least one measure selected from the measures of shielding, filtering and spatial separation, characterized by the fact that the control unit (1) has a metallic shield (33) within the third inner zone (6) which separates a first subzone (31) in which the logic board (9) is arranged and a second subzone (32) in which the power board (10) and the inverter (11) are arranged.

Description

[0001] The invention relates to a control unit, in particular a high-voltage control unit, for a (purely) electrically driven motor vehicle.

[0002] With the increasing introduction of electrically powered vehicles (electric vehicles), the importance of batteries required to power them is increasing. Batteries are being installed that can provide voltages between 400 V and 800 V in the electric vehicle. Such higher voltages are particularly advantageous because the currents can be reduced while maintaining the same power output, which in turn can reduce the cable cross-sections required for current-carrying capacity and thus the material requirements.

[0003] The problem with higher voltages, however, is that higher operating voltages also result in higher levels of interference. Control units, in particular, play a crucial role in this, as they often represent the main source of interference in mechatronic systems (particularly due to the steep switching edges of the inverters built into the control units). Therefore, an electromagnetic compatibility (EMC) concept must be developed for high-voltage applications in general, and for high-voltage control units in particular, in order to comply with the strict EMC requirements in automotive applications.

[0004] The control units known from the state of the art have the disadvantage that they often cannot comply with the strict EMC requirements or can only do so with adverse effects on the required installation space and costs.

[0005] From DE 10 2021 202 450 A1 a control device according to the preamble of claim 1 is known.

[0006] For further prior art, reference is made to WO 2022 / 038 162 A1, DE 10 2019 100 877 A1, DE 10 2016 226 094 A1 and DE 10 2010 001 152 A1.

[0007] The object of the invention is therefore to avoid or at least mitigate the disadvantages of the prior art. In particular, a control unit, especially a high-voltage control unit, is to be provided that is electromagnetically compatible, simultaneously meets the high installation space requirements, and is cost-effective.

[0008] This object is achieved by a control device having the features of claim 1. Advantageous further developments are the subject of the subclaims.

[0009] Accordingly, this object is achieved according to the invention in that the control unit has a housing that delimits an outer zone located outside the housing from inner zones located within the housing, wherein lines (and optionally an (AC) current sensor (described later) are arranged in a first inner zone, filters are arranged in a second inner zone, and a logic board, a power board, and an inverter are arranged in a third inner zone. The outer zone is separated from the inner zones, and the inner zones are separated from one another by at least one measure selected from the measures of shielding, filtering, and spatial separation.

[0010] This means that the control unit according to the invention utilizes the principles of filtering, shielding, and spatial separation of interference sources and sinks, or spatially specific arrangement, through the zone concept, and combines them to achieve an EMC-robust design. Accordingly, the control unit is divided into different zones, and the transition between two zones incorporates at least one of the three measures: shielding, filtering, spatial separation, or specific spatial arrangement.

[0011] This has the advantage that the different zones ensure that circuit components, such as the inverter (power module) and the logic board (logic PCB), do not negatively influence each other. Furthermore, it ensures that neither external sources of interference negatively influence the control unit nor does the control unit interfere with external systems. In other words, the zone concept meets the EMC requirements both within the control unit itself and externally.

[0012] According to a preferred embodiment, a transition between the outer zone and the first inner zone can be shielded and filtered. This means that all interfaces of the control unit to the outer zone / the environment / an area outside the control unit are filtered and / or shielded. Thus, only very minimal interference escapes from the control unit.

[0013] Preferably, the first interior zone can be the outermost interior zone (compared to the other interior zones) within the control unit. This means that the first interior zone spatially separates / spaces the second and third interior zones from the outer zone. In particular, the first interior zone can preferably completely enclose the second and third interior zones. Preferably, the third interior zone can be the innermost interior zone (compared to the other interior zones) within the control unit.

[0014] According to a preferred embodiment, a transition between the first inner zone and the third inner zone can be filtered by the filters arranged at the transition between the first inner zone and the third inner zone, in the second inner zone. This means that the first inner zone is an area within the housing of the control unit in which all lines leading out of the control unit are already filtered. Furthermore, the first inner zone can be partially shielded, for example to separate a region adjacent to the logic board from a region of the first inner zone adjacent to the inverter. This allows interference from zones with higher interference, in particular from the third inner zone or coming from the inverter, to be shielded with respect to the logic board / to the logic board. Thus, the interference coming from the control unit is low in the first inner zone, but higher than in the outer zone.

[0015] According to the invention, the control unit has a metallic shield within the third inner zone, which separates a first subzone in which the logic board is arranged, and a second subzone in which the power board and the inverter are arranged. By providing different areas in the third inner zone, which is highly susceptible to interference due to the arrangement of components with high interference emissions, such as the inverter, and in which the interference from the logic board and the power board is not yet filtered or shielded, interference sources and interference sinks can be separated from one another by spatial separation and additionally shielded by the metallic shield. This reduces the influence between the logic board, which acts as an interference source and interference sink, and the power board, which generates more severe interference than the logic board.

[0016] According to a preferred embodiment, the filters can include a controller area network filter (CAN EMC filter), a supply filter (supply EMC filter), and / or an RPS temperature filter (RPS + Temp EMC filter), which serve as filters for the logic board. According to a preferred embodiment, the filters can include a high-voltage AC filter (HV AC EMC filter) and / or a high-voltage DC filter (HV DC EMC filter), which serve as filters for the power board and the inverter. The filters ensure that the transition from high interference (in the third internal zone) to low interference (in the first internal zone) occurs in the second internal zone with respect to the interference coming from / generated by the control unit.

[0017] Preferably, the filters can be spatially positioned and, in particular, arranged as close as possible to the interface from the control unit to the outside.

[0018] According to a further development of the preferred embodiment, the high-voltage AC filter can be connected directly downstream of the inverter. This means that the high-voltage AC filter is specifically positioned so that the interference generated in the inverter propagates as little as possible into the control unit.

[0019] According to a further development of the preferred embodiment, the control unit can have an AC current sensor connected downstream of the high-voltage AC filter and arranged in the first internal zone. Because the inverter interference is directly filtered by the high-voltage AC filter, the AC current sensor can be placed in the first internal zone, so that the AC current sensor is subjected to as little interference as possible from the inverter.

[0020] Preferably, the high-voltage AC filter may have at least one ferrite or nanocrystalline core in common mode around all three motor phases.

[0021] According to a further development of the preferred embodiment, the controller area network filter, the supply filter, the RPS temperature filter, and / or the high-voltage AC filter can be unshielded relative to the first interior zone and the third interior zone. This eliminates the need for additional shielding of the filters where it is not absolutely necessary. This means that the controller area network filter, the supply filter, the RPS temperature filter, and / or the high-voltage AC filter are arranged in a first subzone of the second interior zone, in which the filters are spatially positioned, namely as close as possible to the interface from the control unit to the outside, but are not shielded in a separate metallic space.

[0022] According to a further development of the preferred embodiment, the high-voltage DC filter connected downstream of the inverter can be metallically shielded to the first inner zone and / or the third inner zone, in particular the second subzone of the third inner zone. Since this high-voltage DC filter is located in an area with the greatest interference, the additional metallic housing for the control unit is installed as metallic shielding for the high-voltage DC filter. This means that the high-voltage DC filter is arranged in a second subzone of the second inner zone, in which the filter is spatially positioned, namely as close as possible to the interface from the control unit to the outside, and is additionally shielded in a separate metallic space.

[0023] Preferably, the high-voltage DC filter may comprise or consist of X and Y capacitors and at least one ferrite or nanocrystalline core.

[0024] According to the development of the preferred embodiment, the control unit may comprise a DC current sensor which is interposed between the high-voltage DC filter and the inverter and is arranged in the third inner zone.

[0025] According to the development of the preferred embodiment, the control device may have a DC link which is interposed between the DC current sensor and the inverter and is arranged in the third inner zone.

[0026] In other words, the invention relates to a control unit divided into zones, which essentially consists of the following components: control unit housing, logic board (logic PCB), inverter (power module), AC current sensor, DC current sensor, HV DC EMC filter, power board, various interfaces, intermediate circuit. Zone 0 / outer zone is the area outside the control unit. All interfaces from the control unit to the environment are filtered and / or shielded here. In this area, only very low levels of interference escape from the control unit. Zone 1 / first inner zone is the area inside the housing of the control unit / ECU, but all cables in this area are already filtered. In some cases, interference from zones with higher levels of interference is also shielded in this area, such as the logic board of the power module / inverter. In Zone 1, the interference coming from the device is low, but higher than in Zone 0.Zone 2 / second interior zone comprises the areas in which the filters are located. Within Zone 2, a distinction can be made between Zone 2A / first subzone of the second interior zone, in which the filters are only spatially positioned (as close as possible to the interface from the control unit to the outside) but are not additionally metallically shielded, and Zone 2B / second subzone of the second interior zone, in which the filters are both spatially positioned (as close as possible to the interface from the control unit to the outside) and additionally metallically shielded. In Zone 2, the transition from high interference to low interference occurs with regard to the interference emanating from the control unit. Zone 3 / third interior zone comprises the areas in which the printed circuit boards with circuit components and circuit arrangements without printed circuit boards are located.Zone 3 is highly susceptible to interference and is the "dirty" zone in which the interference from the respective circuit boards has not yet been filtered and shielded. Different areas (interference sources and interference sinks) on the circuit boards and circuit components can be demarcated from one another by spatial separation. Within Zone 3, a distinction can be made between a Zone 3A / first subzone of the third inner zone, in which the logic boards (which act as both an interference source and an interference sink) are located, and a Zone 3B / second subzone of the third inner zone, in which the power electronics are located and in which the inverter represents a strong source of interference. Zones 3A and 3B can be separated from one another by metallic shielding.

[0027] The invention further relates to an implementation of the zone concept. At the transition between Zone 0 / outer zone and Zone 1 / first inner zone, all interfaces of the control unit are filtered to the outside, and in addition, the control unit has a metal housing at this transition with a maximum screw spacing of 7 cm and thus shielding to the outside. At the transition between Zone 1 / first inner zone (i.e. within the metal housing) and Zone 2 / second inner zone, there is no shielding for the circuit boards, but the filter zones (= Zone 2) begin at this transition. The filter circuits begin at the transition between Zone 2 / second inner zone and Zone 3 / third inner zone, when looking from the inside out.

[0028] The invention is explained below with the aid of a drawing. It shows: Fig. 1 is a diagram of a zoned structure of a control device according to the present invention.

[0029] The figure is purely schematic and serves solely to facilitate understanding of the invention. The same elements are provided with the same reference numerals.

[0030] Fig. 1 shows a structure of a control unit 1 according to the invention. The control unit 1 is designed as a high-voltage control unit.

[0031] The control unit 1 has a housing 2. The housing 2 delimits an outer zone 3 located outside the housing 2 from inner zones 4, 5, 6 located in the housing. Lines 7 are arranged in a first inner zone 4. The lines 7 are already filtered, ie a filter is connected upstream. Filters 8 are arranged in a second inner zone 5. A logic board 9 with microcontroller 9a, a power board 10 and an inverter 11 are arranged in a third inner zone 6. Fig.1, in particular the power module is referred to as inverter 11, whereby alternatively the entire area in which the power module is arranged could also be referred to as inverter 11.

[0032] In the control unit, the outer zone 3 is separated from the inner zones 4, 5, 6 and the inner zones 4, 5, 6 are separated from each other by at least one measure selected from the measures of shielding, filtering and spatial separation.

[0033] Outer zone 3 (zone 0) is an area outside of control unit 1. All interfaces between control unit 1 and the environment are filtered and shielded. In this area, very little interference escapes from control unit 1.

[0034] The first inner zone 4 (zone 1) is an area within control unit 1. All interfaces / lines 7 in this area are filtered and, in some cases, additionally shielded. Only minor interference from control unit 1 escapes in this area, but higher levels than from outer zone 3.

[0035] The second inner zone 5 (zone 2, or 2A and 2B) is an area in which the filters 8 are located. In a first subzone 12 of the second inner zone 5 (zone 2A), the interfaces or the filters 8 are not additionally shielded. In a second subzone 13 of the second inner zone 5 (zone 2B), the interfaces or the filters 8 are additionally metallically shielded. The second inner zone 5 utilizes the principle of specific spatial placement, in which the filters 8 are placed as close as possible to the interface from the control unit 1 to the outside.

[0036] A "Logic PCB Filter" area 14 is assigned to the first subzone 12 of the second inner zone 5. A supply filter 15 (supply EMC filter) and a controller area network filter 16 (CAN EMC filter) are located in this area. Transmission occurs via a Level 0 IF line 17 to the supply 18 and CAN 19, respectively.

[0037] A "Logic PCB Filter Sensor" area 20 is assigned to the first subzone 12 of the second inner zone 5. An RPS temperature filter 21 (RPS + Temp EMC Filter) is located in this area. Transmission occurs via a Level 0 IF line 17 to the RPS + Temp 22.

[0038] An "HV AC Filter" area 23 is assigned to the first subzone 12 of the second inner zone 5. A high-voltage AC filter 24 (HV AC EMC filter) is arranged in this area. Transmission occurs via a Level 1 IF line 25 to an AC current sensor 26 (AC current sensor) and from there via a Level 0 IF line 17 to an electric drive motor 27 (EM). The AC current sensor 26 is connected downstream of the high-voltage AC filter 24 and is arranged in the first inner zone 4.

[0039] An "HV DC Filter" area 28 is assigned to the second subzone 13 of the second inner zone 5. A high-voltage DC filter 29 (HV DC EMC filter) is located in this area. Transmission occurs via a Level 0 IF line 17 to a high-voltage supply 30 (HV supply).

[0040] The third inner zone 6 (zone 3 or 3A and 3B) is an area in which the logic board 9, the power board 10, and the inverter 11 are located. In a first subzone 31 of the third inner zone 6 (zone 3A), the interfaces are unfiltered and unshielded. In a second subzone 32 of the third inner zone 6 (zone 3B), the interfaces are unfiltered and unshielded. The third inner zone 6 utilizes the principle of specific spatial placement, in which the logic board 9 is arranged separately from the power board 10 and the inverter 11. Furthermore, the first subzone 31 and the second subzone 32 are separated from each other by a metallic shield 33. Furthermore, the second subzone 32 of the third inner zone 6 (zone 3B) utilizes the principle of specific spatial placement, in which the power board 10 is arranged separately from the inverter 11.

[0041] The "Logic PCB Filter" 14 and "Logic PCB Filter Sensor" 20 areas are located in the first subzone 31 of the third inner zone 6 (Zone 3A). The "HV AC Filter" 23 and "HV DC Filter" 28 areas are located in the second subzone 32 of the third inner zone 6 (Zone 3B).

[0042] The logic board 9 with the microcontroller (µC) 9a is connected to the power board 10 (power PCB / gate driver) via a Level 1 IF line 25. The power board 10 is connected to the inverter 11 (power module) via a Level 1 IF line 25.

[0043] The inverter 11 is connected to the high-voltage AC filter 24 via a Level 1 IF line 25. In particular, the high-voltage AC filter 24 is connected directly downstream of the inverter 11. The inverter 11 is connected to a DC link 33 (located in the second subzone 32 of the third inner zone 6 (Zone 3B)) via a Level 1 IF line 25. The DC link 33 is connected to a DC current sensor 34 (located in the second subzone 32 of the third inner zone 6 (Zone 3B)) via a Level 1 IF line 25. The DC current sensor 34 is connected to the high-voltage DC filter 29 via a Level 0 IF line 17. List of reference symbols 1 control unit 2 housings 3 Outer zone 4 first inner zone 5 second inner zone 6 third inner zone 7 Line 8 filters 9 Logic board 10 Power board 11 inverters 12 first subzone 13 second subzone 14 Logic PCB Filter area 15 supply filters 16 controller area network filters 17 Level O IF line 18 Supply 19 CAN 20 Logic PCB Filter Sensor area 21 RPS temperature filter 22 RPS + Temp 23 “HV AC Filter” area 24 high-voltage AC filters 25 Level 1 IF line 26 AC current sensor 27 electric drive motor 28 “HV DC Filter” area 29 High-voltage DC filters 30 high-voltage supply 31 first subzone 32 second subzone 33 metallic shielding 34 DC connection 35 DC current sensor

Claims

[1] Control unit (1) for an electrically driven motor vehicle, with a housing (2) which delimits an outer zone (3) located outside the housing (2) from inner zones (4, 5, 6) located in the housing (2), wherein in a first inner zone (4) lines (7), in a second inner zone (5) filters (8) and in a third inner zone (6) a logic board (9), a power board (10) and an inverter (11) are arranged, and the outer zone (3) is separated from the inner zones (4, 5, 6) and the inner zones (4, 5, 6) are separated from each other by at least one measure selected from the measures of shielding, filtering and spatial separation, characterized by , that the control device (1) has a metallic shield (33) within the third inner zone (6), which separates a first sub-zone (31), in which the logic board (9) is arranged, and a second sub-zone (32), in which the power board (10) and the inverter (11) are arranged. [2] Control device (1) according to claim 1, characterized by that a transition between the outer zone (3) and the first inner zone (4) is shielded and filtered. [3] Control device (1) according to claim 1 or 2, characterized by that a transition between the first inner zone (4) and the third inner zone (6) is filtered by the filters (8) arranged in the second inner zone (5). [4] Control device (1) according to one of claims 1 to 3, characterized bythat the filters (8) contain a controller area network filter (16), a supply filter (15) and / or an RPS temperature filter (21), which serve as filters (8) of the logic board (9), and / or that the filters (8) contain a high-voltage AC filter (24) and / or a high-voltage DC filter (29), which serve as filters (8) of the power board (10) and the inverter (11). [5] Control device (1) according to claim 4, characterized by that the high-voltage AC filter (24) is connected directly downstream of the inverter (11). [6] Control device (1) according to claim 5, characterized by that the control unit (1) has an AC current sensor (26) which is connected downstream of the high-voltage AC filter (24) and is arranged in the first inner zone (4). [7] Control device (1) according to one of claims 4 to 6, characterized by that the high-voltage DC filter (29) connected downstream of the inverter (11) is metallically shielded from the first inner zone (4) and / or the third inner zone (6). [8] Control device (1) according to one of claims 4 to 7, characterized by that the controller area network filter (16), the supply filter (15), the RPS temperature filter (21) and / or the high-voltage AC filter (24) are unshielded to the first inner zone (4) and to the third inner zone (6). [9] Control device (1) according to one of claims 4 to 8, characterized by that the control unit (1) has a DC current sensor (35) which is interposed between the high-voltage DC filter (29) and the inverter (11) and is arranged in the third inner zone (6).

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