EMC filter and traction network

Abstract

The invention relates to an EMC filter (1), wherein the EMC filter (1) comprises at least one active filter (13), wherein the active filter (13) comprises at least one coupling circuit (4), an amplifier circuit (5) and at least one output coupling circuit (6), wherein the coupling circuit (4) comprises at least one reverberation element (7), and a traction network (100).

Description

The invention relates to an EMC filter and a traction network for an electric or hybrid vehicle having at least one EMC filter.In particular, fast-switching semiconductor switches, such as pulse inverters, generate high-frequency interference radiation. Therefore, EMC filters are known which reduce this interference radiation. Both active EMC filters and passive EMC filters are known here, which are also used in combination.Such a known EMC filter is known from generic DE 10 2017 223 763 A1.WO 2020 / 048850 A1 discloses a device for suppressing interference signals in voltage sources, in particular for high-voltage voltage sources in a drive train of an electric vehicle, in particular for suppressing differential-mode interference and / or common-mode interference, comprising a measurement region, an amplifier region and an input region, wherein the measurement region inductively couples the input of the amplifier region to at least two supply lines of a voltage source in a galvanically isolated manner by one or more inductive transformers in order to pick off a signal. The feed section inductively couples the output of the amplifier section galvanically isolated by one or more inductive transformers to the at least two supply lines of the voltage source in order to feed in a correction signal. In this case, the amplifier region has a plurality of amplifier paths, at least two of which are parallel, wherein the measurement region has only one inductive transformer per supply line and the feed region has at least one inductive transformer per supply line. In this case, amplifier circuits are used to carry out subtraction and / or addition of the signals of the inductive transformers of the measurement range in the amplifier range, wherein the interference signals resulting therefrom are each coupled into an amplifier circuit, with the result that both common-mode and differential-mode signals can be compensated. The measurement range represents an input coupling circuit.Instead of inductive coupling and decoupling, capacitive coupling and decoupling are also known, which can also be combined with one another.Instead of subtraction and / or addition in the amplifier stage, the common mode or differential mode signals can also be compensated in a targeted manner by the choice of the interconnection of the inductive and capacitive coupling-in and coupling-out networks.The invention is based on the technical problem of providing an improved EMC filter which has fewer feedback effects on the component to be suppressed. Another technical problem is the provision of a traction network with such an EMC filter.The solution of the technical problem is achieved by an EMC filter having the features of claim 1 and a traction network having the features of claim 6.The EMC filter comprises at least one active filter, wherein the active filter comprises at least one input coupling circuit, an amplifier circuit and at least one output coupling circuit, wherein the input coupling circuit comprises at least one Hall element. The advantage of a Hall element is that it does not have to be inserted into the line and also otherwise has no feedback effects on the powers. Furthermore, the Hall element is very fast. The Hall element can also be installed in a sensor. Preferably, only a single Hall element is used. The material of the Hall element is, for example, a III-V, II-VI semiconductor (3 or 2 dimensional) or graphene.In one embodiment, the decoupling circuit is designed as a capacitive or inductive feedback.In a further embodiment, the EMC filter has at least one soft-magnetic core having a slot, wherein the Hall element is arranged in the slot. As a result, the resulting magnetic field is amplified, so that the signals of the Hall element are amplified. In a further embodiment, the EMC filter has two input coupling circuits, at least one circuit being provided which is designed such that a sum signal and a difference signal of the signals are generated at the Hall elements, the EMC filter having an amplifier circuit and at least one output coupling circuit for the sum signal and at least one amplifier circuit and one output coupling circuit for the difference signal. Thus, common mode and differential mode interference can be compensated very easily, as is described in WO 2020 / 04880 A1.The traction network for an electric or hybrid vehicle has at least one DC voltage source, at least one inverter and at least one electric machine, wherein the DC voltage source and the inverter are connected to one another via HV lines and the inverter is connected to the electric machine via phase lines, wherein the traction network has at least one EMC filter which has a first active filter whose incoupling circuit has at least one Hall element.In one embodiment, the EMC filter is associated with the HV lines.Alternatively or additionally, the EMC filter is assigned to the phase lines.The invention is explained in more detail below with reference to preferred exemplary embodiments. The figures show: FIG. 1 shows a schematic illustration of an EMC filter in a first embodiment, FIG. 2 shows a schematic illustration of an EMC filter in a second embodiment, FIG. 3 shows a schematic illustration of a Hall element in a gap of a core, FIG. 4 shows a schematic illustration of a traction network, and FIG. 5 shows a schematic illustration of an EMC filter in a further embodiment.FIG. 1 schematically shows an EMC filter 1 which is arranged between an interference source 2 and an interference sink 4. The interference source is, for example, a pulse inverter and the interference sink 3 is, for example, a high-voltage battery of a traction system. The EMC filter 1 is an active filter, and includes an input circuit 4, an amplifier circuit 5, and an output circuit 6. The input coupling circuit 4 has a Hall element 7, the voltage connections of which are connected to the amplifier circuit 5. Ohmic resistors can be connected in parallel to the Hall element 7 and / or in series to the Hall element 7 in order to set the voltage range. Here, the current I through the Hall element 7 is schematically shown. The decoupling circuit 6 is designed as a capacitor 8.FIG. 2 shows an alternative embodiment of the EMC filter 1, the only difference from the embodiment according to FIG. 1 being that the decoupling circuit 6 is designed as an inductive transformer 9.FIG. 3 shows a soft magnetic core 10 having a slot 11 in which the Hall element 7 is arranged. By increasing the magnetic induction, the measurement sensitivity of the Hall element 7 is improved.FIG. 4 schematically illustrates a traction network 100 for an electric or hybrid vehicle. The traction network 100 has a high-voltage battery 101, an inverter 102 and an electric machine 103. In this case, an EMC filter 1 is arranged between the high-voltage battery 101 and the inverter 102, said EMC filter having a passive filter 12 and an active filter 13, the active filter 13 being constructed as illustrated in FIG. 1 or FIG. 2. The passive filter 12 has, for example, capacitors and cores made of soft magnetic materials (e.g. ferrite rings), through which high-voltage lines HV+, HV- of the traction network are led. Furthermore, the traction network 100 has a further EMC filter 14 between the inverter 102 and the electric machine 103. The EMC filter 14 can be designed as a purely passive filter or purely active filter or as a combined filter. In an embodiment as an active filter, it preferably has a core 10 with slot 11 in which a Hall element 7 is arranged (see also FIG. 3 ), wherein all phase lines 104 of the electric machine 103 are led through the common core 10.FIG. 5 shows a further embodiment for an EMC filter 1, which is arranged, for example, between a high-voltage battery 101 and an inverter 102 in a traction network 100 (see also FIG. 4 ). The EMC filter 1 has a first coupling circuit 4 with a Hall element 7, which is assigned to the positive high-voltage line HV+, and a second coupling circuit 4 with a Hall element 7, which is assigned to the negative high-voltage line HV-. Furthermore, the EMC filter 1 has a circuit 15 which is designed in such a way as to generate a sum signal S and a difference signal D of the signals at the Hall elements 7, the sum signal S and the difference signal D being fed in each case to an amplifier circuit 5. The sum signal S represents the common mode interference (common mode) and the difference signal D represents the differential mode interference (differential mode). Corresponding compensated signals are then applied to the high-voltage lines HV+, HV Via decoupling circuits embodied as inductive transformers, which compensate the interference signals.List of reference characters1 EMC filter 2 interference source 3 interference sink 4 input circuit 5 amplifier circuit 6 output circuit 7 Hall element 8 capacitor 9 inductive transformer 10 soft magnetic core 11 slot 12 passive filter 13 active filter 14 EMC filter 15 circuit 100 traction network 101 high-voltage battery 102 inverter 103 electric machine 104 phase lines D difference signal HV+ high-voltage line HV high-voltage line S sum signalReferences included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedDE 10 2017 223 763 A1

[0003] WO 2020 / 04880 A1 [0004, 0011]

Claims

EMC filter (1), wherein the EMC filter (1) has at least one active filter (13), wherein the active filter (13) has at least one input coupling circuit (4), an amplifier circuit (5) and at least one output coupling circuit (6), characterized in that the input coupling circuit (4) has at least one Hall element (7).The EMC filter according to claim 1, characterized in that the decoupling circuit (4) is designed as a capacitive or inductive feedback.The EMC filter according to claim 1 or 2, characterized in that the EMC filter (1) comprises at least one soft magnetic core (10) with a slot (11), wherein the Hall element (7) is arranged in the slot (11).The EMC filter according to one of the preceding claims, characterized in that the EMC filter (1) comprises at least one passive EMC filter (12).The EMC filter according to one of the preceding claims, characterized in that the EMC filter (1) has two input coupling circuits (4), wherein at least one circuit (15) is provided which is designed such that a sum signal and a difference signal (S, D) of the signals are generated at the Hall elements (7), wherein the EMC filter (1) has an amplifier circuit (5) and at least one output coupling circuit (6) for the sum signal (S) and an amplifier circuit (5) and at least one output coupling circuit (6) for the difference signal (D).Traction network (100) for an electric or hybrid vehicle, wherein the traction network (100) has at least one DC voltage source, an inverter (102) and at least one electric machine (103), wherein the DC voltage source and the inverter (102) are connected to one another via HV lines (HV+, HV-) and the inverter (102) is connected to the electric machine (103) via phase lines (104), characterized in that the traction network (100) has at least one EMC filter (1) according to one of the preceding claims.Traction network according to Claim 6, characterized in that the EMC filter (1) is assigned to the HV lines (HV+, HV-).Traction network according to Claim 6 or 7, characterized in that the EMC filter (1) is assigned to the phase lines (104).

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