DE102018121936A1 - Method and amplifier circuit for increasing inductance - Google Patents

Abstract

The solution according to the invention is a method for suppressing interference signals in at least one supply line, in particular in at least one supply line for high-voltage sources in a drive train of an electric vehicle. The at least one supply line has at least two inductive transmitters, which couple an amplifier circuit to the supply line in an electrically isolated manner. The at least two inductive transmitters each have a primary circuit and a secondary circuit, the at least one primary circuit being assigned to the supply line and the at least one secondary circuit being assigned to the amplifier circuit (2), with an inductance of the at least one primary circuit of a first transformer in the at least one supply line is designed to suppress interference signals, and a signal is tapped from the supply line by means of a second transformer and is fed to an input of the amplifier circuit (2). It is essential that the inductance of the at least one primary circuit of the first transformer is increased by the amplifier circuit (2) feeding a correction signal into the first transformer and the amplifier circuit (2) forming the correction signal by amplification from the signal of the second inductive transmission.

Description

The invention relates to a method for suppressing interference signals in voltage sources, in particular in high-voltage sources for vehicles, with the features of the preamble of claim 1.

Filter arrangements for suppressing interference signals for drive trains for vehicles are known in practice. Due to the requirements for the frequency response and the prevailing high voltages and currents, passive components are used almost exclusively, which are large and expensive.

Active filter concepts are also known, for example from WO 2003/005578 A1 which, however, can mainly be used for applications in signal processing or for applications in which lower voltages and / or lower powers prevail.

The object of the invention is to provide an improved, cost-effective and advantageous method and a device for suppressing interference signals, which can also be used at higher voltages and / or powers and which requires less space and has a high interference signal suppression.

This object is achieved with a method according to the features of claim 1.
The solution according to the invention is a method for suppressing interference signals in at least one supply line, in particular in at least one supply line for high-voltage sources in a drive train of an electric vehicle. The at least one supply line has at least two inductive transmitters, which couple an amplifier circuit to the supply line in an electrically isolated manner. The at least two inductive transmitters each have a primary circuit and a secondary circuit, the at least one primary circuit being assigned to the supply line, and the at least one secondary circuit being assigned to the amplifier circuit, with an inductance of the at least one primary circuit of a first transformer in the at least one a supply line for suppressing interference signals is formed, and wherein a signal is tapped from the supply line by means of a second transformer and fed to an input of the amplifier circuit. It is essential that the inductance of the at least one primary circuit of the first transformer is increased by the amplifier circuit feeding a correction signal into the first transformer and the amplifier circuit forming the correction signal by amplification from the signal of the second inductive transmission.

It can be provided that an interference voltage current is converted into a voltage by the second inductive transformer. This voltage is amplified via a pre-stage of the amplifier circuit or influenced in the frequency response. The voltage signal amplified by the preamplifier undergoes current amplification in a power amplifier and is fed into the supply line as a correction current via the first inductive transformer.

The amplifier circuit is in particular designed such that the interference voltage tapped off from the supply line is present at the input of the amplifier voltage and the amplifier circuit feeds a correction current based on this interference voltage back into the supply line. In contrast to a real increase in inductance, which takes place, for example, through more coil windings or another core material, the inductance is increased purely electronically. This has the advantage that there are no additional ohmic losses in the supply line. The problem of saturation of the core material of an inductive transmitter is also reduced in the method according to the invention. This advantage is essential in order to be able to transmit high performance, as required in traction drives in vehicles, with as little loss as possible and without interference. Furthermore, costs and space can also be saved by the method according to the invention.

In the method according to the invention, it is provided to suppress common-mode disturbances and / or push-pull disturbances. The signal in the supply line for forming the correction signal can be a push-pull interference signal or a common-mode interference signal, or can be used to obtain a push-pull interference signal or a common-mode interference signal. In the event of push-pull interference, the signal can be read from a transformer from the supply line and then corresponds to the interference signal. In the case of push-pull interference, it is also possible to obtain a push-pull interference signal by differential amplification of the signals from several transmitters in the case of several supply lines. In the case of common mode interference, the signal can be read out from a transformer with one primary circuit per supply line in the case of several supply lines and then corresponds to the interference signal. In the case of common mode interference, it is also possible to obtain a common mode interference signal by adding amplification of the signals from several transmitters from several supply lines.

When suppressing interference signals, it can simply be assumed that in In a simple model, a source of interference (transmitter) generates an interference. This interference reaches the interference sink (receiver) via a coupling path and thus influences the receiver. In general, a distinction is made between common mode interference sources and differential mode interference sources. Common mode interference sources drive common mode interference currents, which flow in the same direction in all conductors to the receiver. Push-pull interference sources drive push-pull interference currents that propagate in the same way as the useful signal currents.

The interference current can be composed of a symmetrical and / or an asymmetrical part. With a symmetrical interference current, the currents in the lines are in push-pull and are also called push-pull interference or DMN. In the case of an asymmetrical interference current, the currents in the lines are in common mode. The ground line forms the return conductor. These disturbances are called common mode disturbances or CMN.

Push-pull disturbances, or also called differential mode (DM) noise (DMN) (hereinafter DMN), are generated in the circuit by push-pull interference sources. These push-pull interference sources can have their origin e.g. in magnetic coupling (or also called inductive coupling) or galvanic coupling in the circuit (lines) or by common-mode / push-pull conversion. Push-pull interference sources are usually arranged in series with the useful signal source. Push-pull interference or DMN can be push-pull interference currents, e.g. in the forward and return conductor of a signal circuit, in opposite directions.

Common mode interference, or also called Common Mode (CM) Noise (CMN) (hereinafter CMN), are generated in the circuit by common mode interference sources. These common mode sources can originate e.g. in capacitive coupling, potential increase from ground / ground or grounding points or in potential differences of spatially separated ground and ground terminals. Common mode interference sources are usually arranged between a circuit and a reference potential. Common mode interference or CMN can cause common mode interference currents, e.g. flow in the same direction to the receiver in all conductors of a signal core.

In the method according to the invention, the amplifier circuit with the inductive transmitters can be looped into or used between the battery or a rechargeable battery and a source of interference.

In the method according to the invention, it can be provided that the degree of increase in inductance is specifically determined by determining the voltage gain of the amplifier circuit. By determining a corresponding frequency response of the amplifier, a frequency-dependent increase in the inductance can also be achieved, for example in order to better suppress interference signals with specific frequencies.

It can advantageously be provided that the self-resonance frequency of the electrical system is reduced by feeding in the correction signal. As a result, in particular the radiation behavior of the supply line can be improved and the electromagnetic load on the surrounding systems can be reduced.

An electrical system is preferably understood to mean a circuit comprising a voltage source, consumers and supply lines. The electrical system preferably comprises a rechargeable battery, an electric motor operated via an inverter and intermediate supply lines, the supply lines connecting the rechargeable battery to the inverter and / or the electric motor. Most preferably, the electrical system is a voltage supply system for a traction drive for an electric vehicle.

The resulting coil is of high quality and can form an oscillatory resonant circuit with the capacities in the system. In order to reduce the risk of natural vibrations occurring, it is advantageous to selectively dampen the coil accordingly, or to reduce the gain of the amplifier as a function of frequency.

In particular, the inductance is increased in a frequency range in which interference signals are to be expected, and in a range in which the natural resonance frequency of the electrical system lies.

The interference signals are preferably to be expected in a higher frequency range than the resonance frequency of the electrical system, so that the increase in inductance is lower at low frequencies or can be eliminated entirely and only becomes effective at higher frequencies. The increase in inductance can preferably be reduced or switched off below a frequency of 50 kHz, preferably 20 kHz, and can be correspondingly effective at a higher frequency. The pre-stage can preferably be designed as a low-pass or band-pass or high-pass or band-stop to determine the frequency response.

A frequency-dependent increase in the inductance can preferably be formed. In particular, in that the amplifier circuit is designed as a low-pass or high-pass or bandpass or bandstop.

Band-stop means that the natural resonance frequency of the system is left out, preferably by the amplifier not increasing the inductance in the area of the natural resonance frequency or only increasing it slightly. High pass means the suppression of interference signals with frequencies higher than the natural frequency. Low pass means the suppression of interference signals with frequencies lower than the natural frequency. Bandpass means suppression of interference signals in a defined range, which is preferably outside the natural resonance frequency.

It can be provided that the inductance of the primary circuit of the first transformer is increased by tapping an interference signal via the second inductive transformer in a first stage of the amplifier circuit and performing voltage amplification, and performing power amplification in a second stage of the amplifier circuit.

It can be provided that the amplifier circuit is coupled to the supply line in that the supply line is enclosed by a hinged transformer.

It can be provided that the coil of a primary circuit of the first and / or further transformer is in each case formed by a line section of the supply line.

It can preferably be provided that the primary circuit is formed exclusively by a line section of the supply line. Coupling is thus possible in a simple manner even in the case of rigid bars, the inductance of the primary circuit then being determined by the extent of the ferrite core or the second coil.

It can be provided that the correction signal is formed by the amplifier circuit by voltage amplification and inversion of the signal tapped by means of the second transformer.

It can be provided that the self-resonance frequency of the electrical system is reduced by the amplifier circuit, in particular that the self-resonance frequency of the electrical system is determined by specifying the gain factor of the amplifier circuit.

It can be provided that the second transformer taps the signal from the supply line and the first transformer, in series with the second transformer, feeds a correction signal into the supply line.

The object of the invention is further achieved by a device for suppressing interference signals in at least one supply line, preferably for using the method according to one of the embodiments according to the invention, in particular in at least one supply line for high-voltage sources in a drive train of an electric vehicle. The at least one supply line has at least two inductive transmitters, which couple an amplifier circuit in an electrically isolated manner to the supply line, the at least two inductive transmitters each having a primary circuit and a secondary circuit, and the at least one primary circuit being assigned to the supply line, and wherein the at least one secondary circuit is assigned to the amplifier circuit, and an inductance of the at least one primary circuit of a first transformer is formed in the at least one supply line for suppressing interference signals. It is essential here that the amplifier circuit is designed as a discrete semiconductor amplifier, preferably a two-stage discrete transistor amplifier, and increases the inductance of the at least one primary circuit of the first transformer, in that the amplifier circuit feeds a correction signal into the first transformer, which it generates by means of voltage amplification by means of the second transmitter tapped signal forms.

The device according to the invention increases the inductance purely electronically, in contrast to the real increase in inductance, for example by means of more coil windings. The purely electronic increase means that there are no additional ohmic losses in the supply line. This advantage is essential to be able to transmit high performance without loss.

The features and advantages described below represent optional configurations and relate both to the method according to the invention and to the device according to the invention, without being restrictive.

In particular, it is understood that galvanic isolation here means that two circuits are designed separately from one another, i.e. there is no direct galvanic connection via a cable. The circuits are separated by electrically non-conductive coupling elements. In the case of electrical isolation, the electrical potentials of the two circuits are separated from one another, and the circuits are then isolated from one another. The transmission of current or signals takes place via induction.

For example, the transmitter can preferably consist of two coupled to one another Inductors can be constructed similarly to a transformer, the components of the transformer being specified to ensure good information transmission over a relatively wide frequency range. Preservation of the signal shape is preferably of great importance in the case of a transformer, ie a high linearity and as little distortion as possible are desired in the transformer.

In particular, it can be provided that the transmitter has a core of punched individual sheets which are insulated from one another by insulating, chemically applied phosphating layers. The insulation drastically reduces eddy currents that would heat the core. It can also be provided that the core consists of a ferrite or a ferromagnetic material or an iron. The core can be designed as a ring core or as a split ring core. The advantage of a toroid is that it forms an air-gap-free, closed magnetic circuit. U-cores or E-cores or similar embodiments are also possible.

It can further be provided that, alternatively, the transmitter can also be designed as an air transmitter. This means that the transformer has two inductors which are inductively coupled to one another by their spatial proximity. A solid core for coupling the inductors is not necessary in this case.

It can also be provided that the inductive coupling of the supply line of the voltage source to the amplifier circuit can also be implemented via a coil which is wound in the region of the line section of the supply line. The coil and the line section of the supply line form the transformer.

It can preferably be provided that high-voltage sources are voltage sources with voltages Spann 60 V, preferably meadow vor 120 V, most preferably 240 240 V. The voltage sources can deliver electrical powers of greater than 500 W, preferably greater than 1 kW, most preferably greater than 10 kW.

The device preferably works as follows: The second inductive transformer converts an interference voltage current into a voltage. This voltage is amplified via a pre-stage of the amplifier circuit or influenced in the frequency response. The voltage signal amplified by the preamplifier undergoes current amplification in a power amplifier and is fed into the supply line as a correction current via the first inductive transformer.

In particular, the inductance is increased in the device in a frequency range in which interference signals are to be expected, and in a range in which the natural resonance frequency of the electrical system lies. The interference signals are preferably to be expected in a higher frequency range than the resonance frequency of the electrical system, so that the increase in inductance is lower at low frequencies or can be eliminated entirely and only becomes effective at higher frequencies. The increase in inductance can preferably be reduced or switched off below a frequency of 50 kHz, preferably 20 kHz, and can be correspondingly effective at a higher frequency. The pre-stage can preferably be designed as a low-pass or band-pass or high-pass or band-stop to determine the frequency response.

A frequency-dependent increase in the inductance can preferably be formed. In particular, in that the amplifier circuit is designed as a low-pass or high-pass or bandpass or bandstop.

Band-stop means that the natural resonance frequency of the system is left out, preferably by the amplifier not increasing the inductance in the area of the natural resonance frequency or only increasing it slightly. High pass means the suppression of interference signals with frequencies higher than the natural frequency. Low pass means the suppression of interference signals with frequencies lower than the natural frequency. Bandpass means suppression of interference signals in a defined range, which is preferably outside the natural resonance frequency.

The resulting coil is of high quality and would form an oscillatory resonant circuit with the capacities in the system. In order to reduce the risk of natural vibrations occurring, it is necessary to selectively dampen the coil accordingly or to reduce the gain of the amplifier depending on the frequency

In addition, it can be provided that the two-stage amplifier circuit has a preliminary stage for voltage amplification and an output stage for current amplification. It can be provided that the input of the amplifier is the input of the preamplifier and the output of the amplifier is the output of the output stage.

It can be provided that the amplifier is designed as a discrete amplifier, in particular that the pre-stage and the final stage are formed from discrete semiconductors, preferably from transistors and / or field-effect transistors. This enables a short signal runtime with a simple structure. This will be a good one Frequency behavior as well as good phase fidelity achieved. The preliminary stage and the final stage can preferably have the same type of semiconductor.

In one configuration, the preliminary stage can be designed as a push-pull amplifier. This enables very good signal fidelity and a wide frequency response of the voltage amplification. In particular, the pre-stage can be constructed as a symmetrical push-pull amplifier.

It can be provided that the base current of the semiconductor amplifier, preferably the transistors of the pre-stage of the amplifier circuit, is stabilized with a transistor via a constant current source, preferably that the constant current source has a field effect transistor or MOSFET (metal oxide semiconductor field effect transistor). This enables an easy to implement and yet exact definition of the working point of the preliminary stage. By comparing the temperature characteristics of the constant current source with the transistor of the pre-stage, the gain can be kept constant over a wide temperature range.

It can advantageously be provided that the amplifier circuit has a signal transit time between input and output which is less than or equal to 500 ns, preferably less than or equal to 20 ns, most preferably less than or equal to 6 ns. This enables good interference suppression both at low frequencies and at high frequencies. For example, interference signals in the range from 1 Hz to 10 MHz, preferably in the range from 10 Hz to 2 MHz, can be effectively suppressed.

In particular, it can be provided that the output stage can be cascaded and the preliminary stage controls a number of cascadable output stages, in particular two cascaded output stages or four cascaded output stages or six cascaded output stages or eight cascaded output stages. As a result, higher outputs can be achieved or several coils can be controlled separately.

It can advantageously be provided that the amplifier circuit increases the inductance of the first transformer by voltage amplification of the tapped signal in the amplifier. In particular, the increase in inductance can be determined by the measure of the voltage amplification of the amplifier circuit.

It can be provided that the amplifier circuit reduces the natural resonance frequency of the electrical system. In particular, this reduces the radiation behavior of the supply line in the event of interference signals.

It can be provided that the primary circuits of the transformers are looped into the supply line, preferably form a line section of the supply line, and that the inductance of the primary circuits is designed for a power greater than or equal to 100 W, preferably 500 W, most preferably 1 kW.

In particular, it can be provided that the supply line has a voltage of greater than or equal to 60 V, preferably greater than or equal to 120 V, most preferably greater than or equal to 240 V.

In one embodiment it can be provided that the supply line is designed as a single-pole supply line. Alternatively, the supply line can have a plurality of lines, for example, can be designed as a multi-pole or as a multi-phase voltage supply line with a number of individual lines.

It can be provided that the two transmitters are connected in series in the supply line.

It can be provided that the coils of the primary circuits of the transformers are each formed by a line section of the supply line. This enables a particularly simple assembly, since a line section of the supply line does not have to be interrupted, but rather directly forms the inductance of the primary circuit. For example, a coil of the transmitter can be inductively coupled to this line section and / or a core of the inductive transmitter can be coupled to the line section of the supply line, for example by placing the core on the line section of the supply line.

It can be provided that the core of the inductive transmitter has a core material made of a ferrite or a ferromagnetic material or an iron.

It can preferably be provided that the amplifier circuit forms the correction signal by voltage amplification and inversion of the interference signal in the first amplifier stage.

In one embodiment it can be provided that the supply line is designed for the voltage or power supply of an electric motor, in particular a traction drive or an air conditioning compressor. The supply line can be connected to a supply battery and have a y-capacitor for current buffering.

It can be provided that the inductive transformer as a toroidal core transformer with one turn is trained per line. It can also be provided that the inductive transformer has a ring core and the supply line is led through the ring core, or that one turn is formed per supply line.

For example, it can be provided that the inductance of the primary circuit has a single primary circuit coil. Alternatively, it can be provided that the inductance of the primary circuit has a plurality of separate primary circuit coils or a primary circuit coil with a plurality of windings or taps.

It can be provided that the transmitter has a core material made of a ferrite or a ferromagnetic material or an iron.

In particular, it can be provided that the transformer is designed to be foldable in order to enclose the supply line and to connect it inductively to a line section of the supply line.

It can be provided that the transmitter from the primary circuit to the secondary circuit has a transmission ratio of greater than or equal to 1 to 1 or greater than or equal to 1 to 4, preferably greater than or equal to 1 to 10, most preferably greater than or equal to 1 to 100.

In one embodiment it can be provided that the device for suppressing interference signals is designed for a plurality of supply lines or multi-phase supply lines by the device having an inductive transformer, the primary circuit of the inductive transformer having a plurality of coils, each of which is connected to one of the plurality of supply lines and the secondary circuit of the transformer is connected to the amplifier circuit.

It can further be provided that the device for suppressing interference signals is designed for a plurality of supply lines or for multi-phase supply lines, in that the device has a plurality of transmitters corresponding to the number of supply lines, the primary circuit of an inductive transmitter being connected to one of the supply lines and the Secondary circuit of all inductive transmitters is connected to the same amplifier circuit.

It can also be provided that the device for suppressing interference signals in bipolar voltage sources is formed with a positive and a negative supply line, in that the device has two transmitters, a first transmitter with its primary circuit of the positive supply line and the second transmitter with its Primary circuit of the negative supply line are assigned and the secondary circuit of both transmitters are connected to the same amplifier circuit.

In one embodiment it can be provided that the voltage source has a battery or a rechargeable battery, in particular a traction battery, and supplies an electric motor with electrical energy, preferably supplies an electric motor in an electric vehicle with electrical energy.

The disturbances to be filtered can originate, for example, from a disturbance source connected to the supply line, which is a converter or a voltage converter or an inverter or a speed controller of an electric drive.

It can be provided that the amplifier circuit has a voltage supply that is derived from the supply line, preferably that the amplifier circuit has a symmetrical voltage supply that is derived from a positive and a negative supply line, or that the amplifier circuit has a voltage supply that consists of a separate low voltage source is derived.

It can be provided that the preliminary stage and the final stage have a common voltage supply that is derived from the supply line, preferably that the preliminary stage and the final stage have a common symmetrical voltage supply that is derived from a positive and a negative supply line, or that the Preamplifier and the final stage have a common power supply, which is derived from a separate low voltage source.

The object is further achieved by an interference suppression module for retrofitting voltage sources, in particular high-voltage sources in a drive train of an electric vehicle, comprising a housing in which a device for suppressing interference signals according to one of the preceding embodiments is accommodated.

It can be provided that the interference source has a housing with an installation space for receiving the amplifier circuit or the interference suppression module, the amplifier circuit or the interference suppression module being accommodated in the installation space and being mechanically connected to the housing of the interference source.

The object is further achieved by a traction drive for an electric vehicle comprising a traction battery, an electric motor the traction battery is supplied with energy via a speed controller, and a supply line that connects the speed controller to the traction battery. It is essential here that the supply line has a device for suppressing interference signals according to one of the preceding embodiments.

The object is further achieved by a method for producing a traction drive with a device for suppressing interference signals according to one of the preceding embodiments, in that the supply line (s) is / are interrupted in a first step and a device in accordance with precedent versions are used, or in that in a first step the two inductive transmitters are looped into the supply line / s with a device according to the prior designs.

The object is further achieved by a method for suppressing DMN according to one of the preceding methods, in that the DMN interference signal is read out by placing the transmitter in only one supply line for reading out a signal, or by differential amplification of the signals from several transmitters in the case of several Supply lines a DMN interference signal is received. A correction signal is then generated from the interference signal in the amplifier circuit and feeds into the first transformer in a supply line in order to suppress the interference signal.

The object is further achieved by a method for suppressing CMN, in accordance with one of the preceding methods, in that the CMN interference signal is read out in a plurality of supply lines for reading out a signal by means of a plurality of primary circuit coils of the transformer, or by an amplification of the signals from a plurality of signals Transmitters in several supply lines a CMN interference signal is obtained. A correction signal is then generated from the interference signal in the amplifier circuit and feeds into the first transformer in a supply line in order to suppress the interference signal.

• 1 Erstes erfindungsgemäßes Ausführungsbeispiel einer Schaltungsanordnung einer Vorrichtung zur Unterdrückung von Störsignalen, vorzugsweise zum Unterdrücken von Gegentaktstörungen;
• 2 Erstes erfindungsgemäßes Ausführungsbeispiel einer Vorrichtung zur Unterdrückung von Störsignalen in einer Versorgungsleitung;
• 3a Spannungsverlauf zwischen den Messpunkten 6 aus 1 mit passivem Filter in der Versorgungsleitung 8 ohne zwischengeschalteter erfindungsgemäßer Vorrichtung zum Unterdrücken von Störsignalen;
• 3b Fouriertransformation des Spannungsverlaufes aus 3a;
• 3c Spannungsverlauf zwischen den Messpunkten 6 aus 1 mit zwischengeschalteter erfindungsgemäßer Vorrichtung zum Unterdrücken von Störsignalen aus 2;
• 3d Fouriertransformation des Spannungsverlaufes aus 3c;
• 4 Zweites erfindungsgemäßes Ausführungsbeispiel einer Schaltungsanordnung einer Vorrichtung zur Unterdrückung von Störsignalen, vorzugsweise zum Unterdrücken von Gleichtaktstörungen;
• 5 Erstes erfindungsgemäßes Ausführungsbeispiel einer Vorrichtung zur Unterdrückung von Störsignalen in zwei Versorgungsleitungen;
• 6a Spannungsverlauf zwischen den Messpunkten 6 aus 4 mit passivem Filter in der Versorgungsleitung 8 ohne zwischengeschalteter erfindungsgemäßer Vorrichtung zum Unterdrücken von Störsignalen;
• 3b Fouriertransformation des Spannungsverlaufes aus 6a;
• 6c Spannungsverlauf zwischen den Messpunkten 6 aus 4 mit zwischengeschalteter erfindungsgemäßer Vorrichtung zum Unterdrücken von Störsignalen aus 5;
• 6d Fouriertransformation des Spannungsverlaufes aus 6c;
• 7 Darstellung eines schematischen Schaltungsbeispiels einer Verstärkerschaltung der erfindungsgemäßen Vorrichtung zur Unterdrückung von Störsignalen;

Exemplary embodiments of the invention are shown in the figures and explained below. Show:

• 1 First exemplary embodiment according to the invention of a circuit arrangement of a device for suppressing interference signals, preferably for suppressing push-pull interference;
• 2nd First exemplary embodiment according to the invention of a device for suppressing interference signals in a supply line;
• 3a Voltage curve between the measuring points 6 out 1 with passive filter in the supply line 8th without an intermediate device according to the invention for suppressing interference signals;
• 3b Fourier transformation of the voltage curve 3a ;
• 3c Voltage curve between the measuring points 6 out 1 with an interposed device according to the invention for suppressing interference signals 2nd ;
• 3d Fourier transformation of the voltage curve 3c ;
• 4th Second exemplary embodiment according to the invention of a circuit arrangement of a device for suppressing interference signals, preferably for suppressing common mode interference;
• 5 First exemplary embodiment according to the invention of a device for suppressing interference signals in two supply lines;
• 6a Voltage curve between the measuring points 6 out 4th with passive filter in the supply line 8th without an intermediate device according to the invention for suppressing interference signals;
• 3b Fourier transformation of the voltage curve 6a ;
• 6c Voltage curve between the measuring points 6 out 4th with an interposed device according to the invention for suppressing interference signals 5 ;
• 6d Fourier transformation of the voltage curve 6c ;
• 7 Representation of a schematic circuit example of an amplifier circuit of the device according to the invention for suppressing interference signals;

1 shows as an embodiment a circuit arrangement such as can be used for example in an electric vehicle for a traction drive. The circuit arrangement has a bipolar high-voltage source 4th , a frequency converter 5 and a device according to the invention 1 to suppress interference signals. Interference signals can preferably occur in the form of DMN (differential mode noise, also called push-pull interference) and through the device 1 be suppressed.

The device 1 is in the upper supply line 8th between a throttle 3rd and the frequency converter 5 arranged and has an amplifier circuit 2nd on. Between amplifier circuit 2nd and high voltage source 4th are two throttles 3rd and an X capacitor 7 arranged. In order to illustrate the effect of the interference voltage suppression, there are two measuring points in the circuit arrangement 6 drawn. At the measuring points 6 can change the voltage between the supply lines 8th be measured, which information on interference signals between high voltage source 4th and frequency converter 5 gives.

As in 2nd shown is the amplifier circuit 2nd via a first transformer 9 through the lines B1 and B2 and a second transmitter 10th through the lines A1 and A2 with the supply line 8th inductively coupled and galvanically isolated from them. The transmitters 9 and 10th are constructed, for example, from two coupled inductors similar to a transformer, with the components of the transformer 9 and 10th are specified to ensure good information transmission over a relatively broad frequency range.

The transmitters 9 and 10th are composed of a primary circuit with a primary circuit coil 11 which in the supply line 8th are arranged, and a secondary circuit with a secondary circuit coil 12th . The primary circuit and the secondary circuit can be coupled to one another via a core. Through the two primary circuit coils 11 in the supply line 8th two inductors are formed. The start of winding of the coils is shown by a white dot. That of the supply line 8th The transmitted electrical power flows completely through both primary circuit coils 11 . That means these primary circuit coils 11 need to the maximum power of the supply line 8th be designed.

In the 2nd in the transmitter 2nd The white dots shown, which represent the start of the winding, mean the same winding sense if the dots in the primary circuit and in the secondary circuit are arranged on the same side. Moving a point from left to right then corresponds to an opposite winding sense. This applies to all of the following exemplary embodiments.

The primary circuit coils 11 in the supply line 8th act through their inductance to suppress interference signals. To improve the suppression of interference signals, the inductance of the primary circuit coil 11 of the first transmitter 9 increased by using the second transformer 10th an interference signal is read out and over the lines A1 and A2 into the amplifier circuit 2nd is fed. The amplifier circuit 2nd forms a correction signal from this interference signal and feeds the correction signal via the lines B1 and B2 into the primary circuit coil 11 of the first transmitter 9 on. The correction signal fed in superimposes the interference signal and reduces it. The correction signal fed in is fed in with a slight signal delay and thus causes an increase in the inductance of the primary circuit coil 11 of the first transmitter 9 .

The change in voltage measured between the measuring points 6 in the 1 , is in the 3a to 3c shown. 3a shows the voltage waveform when between high voltage source 4th and frequency converter 5 a periodic trapezoidal interference signal occurs. 3b shows the Fourier transformation of the voltage curve 3a . In the 3a and 3b is not a device according to the invention 1 interposed to suppress interference signals, it is only the primary circuit coil 11 in the supply line 8th available as a pure passive choke.

In the 3c and 3d becomes the voltage curve with the device according to the invention 1 , ie with an intermediate amplifier circuit 2nd , shown. 3c shows the voltage waveform when between high voltage source 4th and frequency converter 5 a periodic trapezoidal interference signal occurs, the device 1 with the amplifier circuit 2nd in the supply line 8th arranged and active. 3d shows the Fourier transformation of the voltage curve 3c . By comparing the 3a with 3c and the 3b with 3d the additional suppression of the interference signal in the supply line 8th with an intermediate amplifier circuit 2nd evident. The amplitude of the interference signal is reduced, and the resulting interference spectrum is also shifted to lower frequencies.

mit N gleich der Anzahl der Wicklungen in der Primärkreis-Spule 11 und V_ideal gleich dem Verstärkungsfaktor. Der Verstärkungsfaktor V_ideal besitzt zusätzlich einen komplexen Korrekturfaktor V_korr und einen Normierungsfaktor Vnorm, da sich der Korrekturfaktor mit dem Induktivitätsverhalten ändert. Damit kann die erhöhte Induktivität Lverst der Primärkreis-Spule 11 L_prim des ersten Übertragers mit zwischengeschalteter Verstärkerschaltung 2 wie folgt berechnet werden: $${\text{L}}_{\text{verst}}={\text{L}}_{\text{prim}}*{\text{V}}_{\text{norm}}*{\left(1+{\text{V}}_{\text{ideal}}+{\text{V}}_{\text{korr}}\right)}^2$$

Die Erhöhung der Induktivität erfolgt dabei im Gegensatz zu der realen Erhöhung der Induktivität, bspw. durch mehr Spulenwicklungen, rein elektronisch, so dass keine zusätzlichen ohmschen Verluste in der Versorgungsleitung 8 entstehen. Dieser Vorteil ist essentiell, um hohe Leistungen verlustfrei übertragen zu können.A simulation of the circuit arrangement 1 with that of the device 1 out 2nd results in an intermediate amplifier circuit 2nd out 7 a mathematical increase in the inductance of the primary circuit coil 11 in the first transformer 9 with a factor of about fifty. This means that with a passive primary circuit coil 11 in the first transformer 9 with a real inductance of approx. 500 nH through the intermediate amplifier circuit 2nd a primary circuit coil 11 in the first transformer 9 is achieved with a virtual inductance of approx. 24 µH. In other words, the amplifier circuit works 2nd like additional windings in the primary circuit coil 11 . This can be expressed arithmetically by $${\text{N}}^{\mathrm{2nd}}\stackrel{\wedge}{=}{\left(\text{N}+{\text{V}}_{\text{ideal}}\right)}^{\mathrm{2nd}}$$

with N equal to the number of windings in the primary circuit coil 11 and V _ideally equal to the gain factor. The gain factor V _ideal additionally has a complex correction factor V _corr and a normalization factor Vnorm, since the correction factor changes with the inductance behavior. This can increase the inductance Lverst of the primary circuit coil 11 L _{prim of} the first transformer with an intermediate amplifier circuit 2nd can be calculated as follows: $${\text{L}}_{\text{understand}}={\text{L}}_{\text{prim}}*{\text{V}}_{\text{standard}}*{\left(1+{\text{V}}_{\text{ideal}}+{\text{V}}_{\text{corr}}\right)}^{\mathrm{2nd}}$$

In contrast to the real increase in inductance, for example through more coil windings, the inductance is increased purely electronically, so that there are no additional ohmic losses in the supply line 8th arise. This advantage is essential to be able to transmit high performance without loss.

4th shows a circuit arrangement with a bipolar high voltage source 4th , a frequency converter 5 and a device 1 to suppress interference signals, preferably CMN (Common Mode Noise, also called common mode interference). The device 1 is in both supply lines 8th arranged and has an amplifier circuit 2nd on. Between amplifier circuit 2nd and high voltage source 4th is an X capacitor 7 and a throttle 3rd arranged. At the measuring points 6 can change the voltage between the supply lines 8th be measured, which information on interference signals between high voltage source 4th and frequency converter 5 gives. Between the high voltage source 4th , the frequency converter 5 and the supply lines 8th are Y capacitors 17th arranged towards the ground.

5 shows a further embodiment of the device 1 for suppressing interference signals with the amplifier circuit 2nd which have a first transformer 9 through the lines B1 and B2 and a second transmitter 10th through the lines A1 and A2 with the supply lines 8th are inductively coupled and galvanically isolated from them. The embodiment of the 5 differs from the embodiment of the 2nd only in that in 5 the transmitters 9 and 10th with both supply lines 8th are inductively coupled. For this purpose, both supply lines 8th one primary circuit coil each 11 on. Like in the 2nd already work in the 5 the inductances of the primary circuit coils 11 as a passive filter to suppress interference signals against CMN.

The 6 show the voltage curve and the Fourier transformation of the voltage curve for a filter circuit 5 with an amplifier circuit 7 in a circuit arrangement 4th .

The change in voltage measured between the measuring points 6 in the 4th , is in the 6a to 6c shown. 6a shows the voltage waveform when between high voltage source 4th and frequency converter 5 a periodic trapezoidal interference signal is fed. 6b shows the Fourier transformation of the voltage curve 6a . In the 6a and 6b is not a device according to the invention 1 interposed to suppress interference signals, there are only the primary circuit coils 11 in the supply lines 8th available as pure passive chokes.

In the 6c and 6d becomes the voltage curve with the device according to the invention 1 , ie with an intermediate amplifier circuit 2nd , shown. 6a shows the voltage waveform when between high voltage source 4th and frequency converter 5 a periodic trapezoidal interference signal is fed in, the device 1 with the amplifier circuit 2nd in the supply lines 8th is arranged. 6d shows the Fourier transformation of the voltage curve 6c . By comparing the 6a with 6c and the 6b 6d is the additional suppression of the interference signal in the supply lines 8th with an intermediate amplifier circuit 2nd evident. Here, too, you can clearly see the shift in the resulting interference spectrum towards lower frequencies.

mit N gleich der Anzahl der Wicklungen in den Primärkreis-Spulen 11 und V_ideal gleich dem Verstärkungsfaktor. Der Verstärkungsfaktor V_ideal besitzt zusätzlich einen komplexen Korrekturfaktor V_korr und einen Normierungsfaktor Vnorm, da sich der Korrekturfaktor mit dem Induktivitätsverhalten ändert. Damit kann die erhöhte Induktivität Lverst der Primärkreis-Spulen 11 L_prim des ersten Übertragers mit zwischengeschalteter Verstärkerschaltung 2 wie folgt berechnet werden: $${\text{L}}_{\text{verst}}={\text{L}}_{\text{prim}}*{\text{V}}_{\text{norm}}*{\left(1+{\text{V}}_{\text{ideal}}+{\text{V}}_{\text{korr}}\right)}^2$$

7 zeigt ein Ausführungsbeispiel der Verstärkerschaltung 2 mit einer Vorstufe 14 und einer Endstufe 15. Der Eingang der Vorstufe 14 ist mit den Leitungen A1 und A2 aus den 2 oder 5 verbunden und liest durch den zweiten Übertrager 10 ein Störsignal ein. Der Ausgang der Endstufe 15 ist über die zwei Leitungen B1 und B2 mit dem ersten Übertrager 9 verbunden und speist ein Korrektursignal in die Versorgungsleitungen 8 über die Primärkreis-Spulen 11 ein.A simulation of the circuit arrangement 4th with that of the device 1 out 5 results in an intermediate amplifier circuit 2nd out 7 a mathematical increase in the inductance of the two primary circuit coils 11 in the first transformer 9 with a factor of about fifty. This means that with passive primary circuit coils 11 in the first transformer 9 with a real inductance of approx. 500 nH through the intermediate amplifier circuit 2nd a primary circuit coil 11 in the first transformer 9 is achieved with a virtual inductance of approx. 24 µH. In other words, the amplifier circuit works 2nd like additional windings in the primary circuit coils 11 . This can be expressed arithmetically by $${\text{N}}^{\mathrm{2nd}}\stackrel{\wedge}{=}{\left(\text{N}+{\text{V}}_{\text{ideal}}\right)}^{\mathrm{2nd}}$$

with N equal to the number of windings in the primary circuit coils 11 and V _ideally equal to the gain factor. The gain factor V _{ideal also} has a complex correction factor V _corr and one Standardization factor Vnorm, since the correction factor changes with the inductance behavior. This can increase the inductance Lverst of the primary circuit coils 11 L _{prim of} the first transformer with an intermediate amplifier circuit 2nd can be calculated as follows: $${\text{L}}_{\text{understand}}={\text{L}}_{\text{prim}}*{\text{V}}_{\text{standard}}*{\left(1+{\text{V}}_{\text{ideal}}+{\text{V}}_{\text{corr}}\right)}^{\mathrm{2nd}}$$

7 shows an embodiment of the amplifier circuit 2nd with a preliminary stage 14 and a power amplifier 15 . The entrance to the prepress 14 is with the lines A1 and A2 from the 2nd or 5 connected and read by the second transmitter 10th an interference signal. The output of the power amplifier 15 is over the two lines B1 and B2 with the first transmitter 9 connected and feeds a correction signal into the supply lines 8th via the primary circuit coils 11 on.

The amplifier circuit 2nd is designed as a two-stage discrete transistor gain. This has the advantage that a very short signal runtime can be realized. The separation into a first amplifier stage for voltage amplification and a second amplifier stage for power amplification also makes it easy to adapt the frequency response of the amplifier circuit 2nd enables.

In a first stage, the preliminary stage 14 , the voltage is amplified and the signal is inverted. For this purpose, the first stage is designed as a push-pull amplifier and has two transistors T1 and T2 on, which carry out a voltage amplification of the interference signal. The base current of the transistors T1 and T2 is via a constant current source each with a MOSFET (metal oxide semiconductor field effect transistor) T5 and T6 stabilized.

This allows a particularly good stabilization of the working point even with large temperature fluctuations.

In a second stage of the amplifier circuit 2nd , the final stage 15 , are two transistors T3 and T4 arranged, which perform a current amplification or impedance adaptation of the correction signal. Also the base current of the output stage transistors T3 and T4 is via a MOSFET (metal oxide semiconductor field effect transistor) T7 and T8 stabilized. This allows particularly good stabilization even with large temperature fluctuations.

With one symmetrical low voltage source each U1 and U2 such as U3 and U4 is on the transistors T1 and T2 , as well as on the transistors T3 and T4 a voltage of ± 12V is applied. For the sake of simplicity, the preliminary stage 13 and the power amp 13 can be fed from the same symmetrical low-voltage source. In this case U1 equal U3 such as U2 equal U4 . Alternatively, for the prepress 12th and the power amp 13 each with its own symmetrical low-voltage sources U1 , U2 , respectively. U3 , U4 be used. The symmetrical low voltage source U1 , U2 , respectively. U3 , U4 can be fed from the high-voltage voltage source via a voltage converter. Alternatively, the low voltage source U1 , U2 , respectively. U3 , U4 from a separate network, for example a 12V or 24V electrical system of an electric vehicle.

The output stage has a cascaded push-pull output stage 16 on, being in 7 only a push-pull output stage 16 is shown. To achieve higher performance, for example, up to eight push-pull output stages 16 be cascaded. With appropriate pre-stage training, more push-pull stages can also be used 16 be cascaded.

Reference list

1

Interference suppression device

2nd

Amplifier circuit

3rd

throttle

4th

High voltage source

5

frequency converter

6

Measuring point

7

X capacitor

8th

supply line

9

First transmitter

10th

Second transformer

11

Primary circuit coil

12th

Secondary circuit coil

13

core

14

Prepress

15

Power amplifier

16

Push-pull output stage

17th

Y capacitor

T1 to T8

transistor

QUOTES INCLUDE IN THE DESCRIPTION

This list of documents listed by the applicant has been generated automatically and is only included for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• WO 2003/005578 A1 [0003]

Claims (43)

Method for suppressing interference signals in at least one supply line (8), in particular in at least one supply line (8) for high-voltage sources in a drive train of an electric vehicle, the at least one supply line (8) having at least two inductive transmitters (9, 10), one Coupling the amplifier circuit (2) in an electrically isolated manner to the supply line (8), the at least two inductive transmitters (9, 10) each having a primary circuit and a secondary circuit, the at least one primary circuit being assigned to the supply line (8), and in each case the at least one secondary circuit is assigned to the amplifier circuit (2), an inductance of the at least one primary circuit of a first transformer (9) being formed in the at least one supply line (8) for suppressing interference signals, a signal from the supply line (8) being formed by means of a second transfer gers (10) tapped and fed to an input of the amplifier circuit (2), characterized in that the inductance of the at least one primary circuit of the first transformer (9) is increased by the amplifier circuit (2) by amplification from the signal of the second inductive Transmission (10) a correction signal is formed and fed into the first transformer (9). Method for suppressing interference signals according to Claim 1 , characterized in that an interference voltage current is converted into a voltage by the second inductive transformer (10), this voltage being amplified via a preamplifier (14) of the amplifier circuit (2) and / or influenced in the frequency response, and this by the preamplifier amplified voltage signal in a power amplifier (15), preferably a power amplifier, experiences a current amplification and is fed via the first inductive transformer (9) as a correction current into the supply line (8). Method for suppressing interference signals according to Claim 1 or 2nd , characterized in that the inductance is increased in a frequency range in which interference signals are to be expected, and in a range in which the natural resonance frequency of the electrical system lies. Method for suppressing interference signals according to one of the preceding claims, characterized in that the degree of increase in inductance is determined via the voltage amplification of the amplifier circuit (2). Method for suppressing interference signals according to one of the preceding claims, characterized in that the natural resonance frequency of the electrical system is reduced by feeding in the correction signal. Method for suppressing interference signals according to one of the preceding claims, characterized in that the inductance of the primary circuit of the first transmitter (9) is increased by tapping an interference signal via the second inductive transmitter (10) in a first stage of the amplifier circuit (2) and a voltage amplification is carried out and in a second stage of the amplifier circuit (2) a power amplification is carried out in order to obtain a correction signal which is transferred to the first transformer (9). Method for suppressing interference signals according to one of the preceding claims, characterized in that the amplifier circuit (2) is coupled to the supply line (8) in that the supply line (8) is enclosed by a hinged transmitter (9, 10). Method for suppressing interference signals according to one of the preceding claims, characterized in that the coil (11) of a primary circuit of the first and / or further transmitters (9, 10) are each formed by a line section of the supply line (8). Method for suppressing interference signals according to one of the preceding claims, characterized in that the correction signal is formed by the amplifier circuit (2) by voltage amplification and inversion of the signal tapped by means of the second transmitter (10). Method for suppressing interference signals according to one of the preceding claims, characterized in that the self-resonance frequency of the electrical system is reduced by the amplifier circuit (2), in particular that the self-resonance frequency of the electrical system is determined by specifying the gain factor of the amplifier circuit (2). Device (1) for suppressing interference signals in at least one supply line (8), preferably for using the method according to one of the Claim 1 to 8th , in particular in at least one supply line (8) for high-voltage sources in a drive train of an electric vehicle, the at least one supply line (8) having at least two inductive transmitters (9, 10) which are electrically isolated from the amplifier circuit (2) with the supply line (8) couple, the at least two inductive transmitters (9, 10) each having a primary circuit and a secondary circuit, the at least one primary circuit being assigned to the supply line (8) and the at least one secondary circuit being assigned to the amplifier circuit (2), wherein an inductance of the at least one primary circuit of a first transformer (10) in the at least one supply line (8) for suppressing interference signals, characterized in that the amplifier circuit (2) is designed as a discrete semiconductor amplifier (T1-T4) and the inductance of the at least one increases a primary circuit of the first transformer (9) by the amplifier circuit (2) feeding a correction signal into the first transformer (9) which it forms by voltage amplification of a signal tapped by means of the second transformer (10). Device (1) for suppressing interference signals Claim 11 , characterized in that the two-stage amplifier circuit (2) has a preliminary stage (14) for voltage amplification and an output stage (15) for current amplification. Device (1) for suppressing interference signals Claim 12 , characterized in that the preliminary stage (14) is constructed as a push-pull amplifier, in particular as a symmetrical push-pull amplifier. Device (1) for suppressing interference signals according to one of the Claims 12 or 13 , characterized in that the output stage (15) can be cascaded and the preliminary stage (14) controls several cascadable push-pull output stages (15), in particular two cascaded push-pull output stages (15) or four cascaded push-pull output stages (15) or six cascaded push-pull output stages (15) or eight cascaded Push-pull output stages (15) driven. Device (1) for suppressing interference signals according to one of the Claims 12 to 14 , characterized in that the base current of the semiconductor amplifier, preferably the transistor of the preliminary stage or the transistors (T1-T4) of the preliminary stage of the amplifier circuit is stabilized with a transistor (T5-T6) via a constant current source, preferably that the constant current source is a field effect transistor or MOSFET ( Metal oxide semiconductor field effect transistor). Device (1) for suppressing interference signals according to one of the Claims 11 to 15 , characterized in that the amplifier circuit (2) has a signal transit time between input and output which is less than or equal to 50 ns, preferably less than or equal to 20 ns, most preferably less than or equal to 6 ns. Device (1) for suppressing interference signals according to one of the Claims 11 to 16 , characterized in that the amplifier circuit (2) increases the inductance of the first transformer (9), preferably that the increase in inductance is determined by the measure of the voltage amplification of the amplifier circuit (2). Device (1) for suppressing interference signals according to one of the Claims 11 to 17th , characterized in that the amplifier circuit (2) reduces the natural resonance frequency of the electrical system. Device (1) for suppressing interference signals according to one of the Claims 11 to 18th , characterized in that the primary circuits of the transformers (9, 10) are looped into the supply line (8), preferably form a line section of the supply line (8), and that the inductance of the primary circuits for a power greater than or equal to 100 W, preferably 500 W, most preferably 1 kW. Device (1) for suppressing interference signals according to one of the Claims 11 to 19th , characterized in that the supply line (8) is designed as a single-pole supply line or that the supply line (8) is designed as a multi-pole or multi-phase supply line (8) with a plurality of individual lines. Device (1) for suppressing interference signals according to one of the Claims 11 to 20th , characterized in that the two transmitters (9, 10) are connected in series in the supply line (8). Device (1) for suppressing interference signals according to one of the Claims 11 to 21 , characterized in that the coils (11) of the primary circuits of the transmitters (9, 10) are each formed by a line section of the supply line (8). Device (1) for suppressing interference signals according to one of the Claims 11 to 22 , characterized in that the amplifier circuit (2) forms the correction signal by voltage amplification and inversion of the interference signal in the first amplifier stage. Device (1) for suppressing interference signals according to one of the Claims 11 to 23 , characterized in that the supply line (8) for voltage or power supply of a Electric motor, in particular a traction drive or an air conditioning compressor. Device (1) for suppressing interference signals according to one of the Claims 11 to 24th , characterized in that the supply line (8) is connected to a supply battery and has a y-capacitor for current buffering. Device (1) for suppressing interference signals according to one of the Claims 11 to 25th , characterized in that the inductive transformer (9, 10) is designed as a toroidal core transformer with one turn per line. Device (1) for suppressing interference signals according to one of the Claims 11 to 26 , characterized in that the inductance of the primary circuit is designed as a single primary circuit coil (11). Device (1) for suppressing interference signals according to one of the Claims 11 to 27 , characterized in that the inductance of the primary circuit has a plurality of separate primary circuit coils (11) or a primary circuit coil (11) with a plurality of windings or taps. Device (1) for suppressing interference signals according to one of the Claims 11 to 28 , characterized in that a line section of the supply line (8) forms the inductance of the primary circuit. Device (1) for suppressing interference signals according to one of the Claims 11 to 29 , characterized in that the transmitter (9, 10) is designed to be foldable in order to enclose the supply line (8). Device (1) for suppressing interference signals according to one of the Claims 11 to 30th , characterized in that the transmitter (9, 10) from the primary circuit to the secondary circuit has a transmission ratio of greater than or equal to 1 to 1 or greater than or equal to 1 to 4, preferably greater than or equal to 1 to 10, most preferably greater than or equal to 1 to 100. Device (1) for suppressing interference signals according to one of the Claims 11 to 31 , characterized in that the device (1) for suppressing interference signals for a plurality of supply lines (8) or multi-phase supply lines (8) is formed by the device having an inductive transmitter (9, 10), the primary circuit of the inductive transmitter (9 , 10) has a plurality of coils (11), each of which is connected to one of the plurality of supply lines (8) and the secondary circuit of the transformer is connected to the amplifier circuit (2). Device (1) for suppressing interference signals according to one of the Claims 11 to 32 characterized in that the device (1) for suppressing interference signals is designed for a plurality of supply lines (8) or for multi-phase supply lines (8) by the device (1) having a plurality of transmitters (9, 10) corresponding to the number of supply lines (8) ), the primary circuit of an inductive transmitter (9, 10) being connected to one of the supply lines (8) and the secondary circuit of all inductive transmitters being connected to the same amplifier circuit (2). Device (1) for suppressing interference signals according to one of the Claims 11 to 33 , characterized in that the device for suppressing interference signals in bipolar voltage sources with a positive and a negative supply line (8) is formed by the device having two transmitters (9, 10), a first transmitter (9) with its primary circuit positive supply line (8) and the second transformer (10) with its primary circuit are assigned to the negative supply line (8) and the secondary circuit of both transformers (9, 10) are connected to the same amplifier circuit (2). Device (1) for suppressing interference signals according to one of the Claims 11 to 34 , characterized in that the voltage source (4) has a battery or a rechargeable battery, in particular a traction battery and supplies an electric motor with electrical energy, preferably supplies an electric motor in an electric vehicle with electrical energy. Device (1) for suppressing interference signals according to one of the Claims 11 to 35 , characterized in that the supply line (8) has a voltage greater than or equal to 60 V, preferably greater than or equal to 120 V, most preferably greater than or equal to 240 V. Device (1) to suppress interference signals according to one of the Claims 11 to 36 , characterized in that the disturbances mainly come from a source of interference connected to the supply line (8), which is a converter (5) or a voltage converter or an inverter or a speed controller of an electric drive. Interference suppression module for retrofitting voltage sources (4), in particular high-voltage sources in a drive train of an electric vehicle, comprising a housing in which a device (1) for suppressing interference signals according to one of the preceding claims is accommodated. Device (1) for suppressing interference signals Claim 38 , characterized in that the interference source (5) has a housing with an installation space for receiving the amplifier circuit (2) or the interference suppression module, the amplifier circuit (2) or the interference suppression module being accommodated in the installation space and being mechanically connected to the housing of the interference source. Traction drive for a vehicle comprising a traction battery, an electric motor which is supplied with energy from the traction battery via a speed controller and a supply line (8) which connects the speed controller to the traction battery, characterized in that the supply line (8) has a device (1) to suppress interference signals according to one of the Claims 9 to 37 having. Method for producing a traction drive with a device for suppressing interference signals according to one of the preceding claims, characterized in that the supply line (s) (8) is / are interrupted in a first step and a device (1) in the interruption point is used according to an embodiment of the preceding claims, or that in a first step the inductive transmitters (9, 10) are looped into the supply line (s) (8) with a device (1) according to an embodiment of the preceding claims. Method for suppressing interference signals according to one of the preceding Claims 1 to 41 characterized in that the method for suppressing push-pull interference (DMN) is formed by placing the second transmitter (10) in only one supply line (8) for reading out a signal, the DMN interference signal is read out, or by differential amplification of the signals a DMN interference signal is obtained from several transmitters in the case of several supply lines (8) and then a correction signal is generated from the interference signal in the amplifier circuit (2), which is fed into the supply line (8) in the first transmitter (9) in order to add the interference signal suppress. Method for suppressing interference signals according to one of the preceding Claims 1 to 41 characterized in that the method for suppressing common mode interference (CMN) is formed by reading out the CMN interference signal by means of a plurality of primary circuit coils (11) of the transmitter (10) in a plurality of supply lines, or by adding amplification of the Signals from a plurality of transmitters (10) in a plurality of supply lines (8), a CMN interference signal is obtained, and then a correction signal is generated from the interference signal in the amplifier circuit (2), which correction signal is fed into the supply lines (8) in the first transmitter (9) is used to suppress the interference signal.

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