Compensation device for compensating leakage current

Abstract

A compensation device (20) for compensating leakage current, the compensation device having a differential current measuring device (22), a power supply network identification device (42; 45), a control device (26), an amplifier (28), a compensation current selection device (36), and a feeding device (39, 41). The power supply network identification device (42; 45) is designed to generate a second signal (V_GRID; V_ES) representing a power supply network (L1, L2, L3, N) connected to an active conductor (51, 52, 53, 54) and supply it to the control device (26). The compensation current selection device (36) is designed to perform feeding of a compensation current (I_COMP) on at least one of at least two different active conductors (51, 54) depending on a third signal (V_SEL), the third signal (V_SEL) being dependent on the second signal (V_GRID; V_ES) in order to select at least one active conductor (51, 54) suitable for the connected power supply network for the feeding.

Description

Technical Field

[0001] The invention relates to a compensation device for compensating a leakage current, and the compensation device is particularly used in a charging device of a vehicle. Background Art

[0002] Leakage currents are currents which flow under normal operating conditions in undesired current paths, for example from the outer conductors (L1 to L3) to the protective conductor (PE). In practice, such leakage currents are generated, for example, by filter capacitors of a power supply filter, which are connected on one side, for example, to a DC voltage path and on the other side to the protective conductor (PE).

[0003] US 2004 / 0189337 A1 shows a leakage current monitor for an integrated circuit.

[0004] US 2011 / 0057707 A1 shows a multiplexer with leakage current detection.

[0005] US 2014 / 0327371 A1 shows a power supply for LEDs with phase cut control and compensation.

[0006] US 2016 / 0154047 A1 shows leakage current detection by means of a test circuit.

[0007] US 2013 / 0043880 A1 discloses a device for determining and compensating for a fault current. Summary of the invention

[0008] The object of the present invention is to provide a novel compensation device for compensating leakage current and a vehicle having such a compensation device.

[0009] This object is achieved by a compensation arrangement described in the next paragraph.

[0010] A compensation device for compensating leakage current, the compensation device having a differential current measuring device, a power supply network identification device, a control device, an amplifier, a compensation current selection device, and a feeding device. The differential current measuring device is designed to detect a first signal representing a differential current of an active conductor and supply it to the control device. The power supply network identification device is designed to generate a second signal representing a power supply network connected to the active conductors and supply it to the control device. The control device is designed to generate a compensation preset signal suitable for compensation according to the first signal and supply it to the amplifier. The amplifier is designed to generate a compensation current depending on the compensation preset signal. The feeding device is designed to enable the compensation current to be fed on at least two different active conductors. The compensation current selection device is designed to perform the feeding of the compensation current on at least one of the at least two different active conductors depending on a third signal, and the control device is designed to generate the third signal depending on the second signal so as to select at least one active conductor suitable for the connected power supply network for the feeding. The influence of the compensation current selection device, depending on the connected supply network, makes it possible to feed the compensation current onto a suitable active conductor.

[0011] According to a preferred embodiment, the power supply network identification device has at least one voltage measuring device and is designed to measure the voltage on at least one of the active conductors by means of the at least one voltage measuring device in order to identify the connected power supply network. The connected power supply network can be identified relatively reliably by measuring the voltage.

[0012] According to a preferred embodiment, the compensation device has a safety device, the safety device has a switch, the switch is connected to a first conductor on the input side, the first conductor is connected to the amplifier, and the switch is designed to selectively connect the first conductor to a second conductor in a first state or to a third conductor in a second state, wherein the second conductor is connected to a protective conductor terminal, wherein the third conductor is connected to the compensation current selection device, and wherein the control device can control the switch. Providing a switch that can connect the first conductor to the protective conductor terminal enables testing of the amplifier.

[0013] According to a preferred embodiment, the switch is designed as a relay. Relays are particularly well suited for use as switches because they have a low resistance when conducting and a high isolation resistance when not conducting. In addition, very fast switching is not required in applications.

[0014] According to a preferred embodiment, the control device is designed to enable a functional check, in which the control device controls the switch so that the switch is in the first state; and in the functional check, the control device supplies the amplifier with a compensation preset signal, which causes a compensation current, in order to check the function of the amplifier without feeding the compensation current via the feed device. This diagnostic possibility increases the safety and testability of the compensation device.

[0015] According to a preferred embodiment, before the power supply network is connected to the active conductors, the control device places the switch in the first state; and the control device places the switch in the second state only under pre-set conditions, and the pre-set conditions include:

[0016] - the power supply network is connected to the active conductors, and

[0017] - generating the third signal dependent on the second signal.

[0018] These pre-set conditions enable more reliable operation.

[0019] According to a preferred embodiment, the first conductor is connected to the third conductor via a capacitor so that even in the first state of the switch the pulses generated on the third conductor can be transmitted to the first conductor. By this measure, even in the first state of the switch the compensation device can perform a measurement and check whether the feed device is connected to a phase or neutral conductor.

[0020] According to a preferred embodiment, the compensation device has a compensation current measuring device, which is designed to measure the compensation current, generate a fourth signal characterizing this compensation current, and supply the fourth signal to the control device. By measuring the compensation current, the control device can check whether the compensation works as specified. If this should not be the case, the compensation device can, for example, increase or reduce the compensation current. This increases reliability.

[0021] According to a preferred embodiment, the compensating device is designed to: when the power supply network identification device identifies a power supply network with a neutral conductor, the compensating current selection device is controlled in such a way that the compensating current is fed by the feeding device on the active conductor to which the neutral conductor is connected. Feeding to the neutral conductor is advantageous because the voltage on the neutral conductor is lower than the voltage on the phase / external conductor. The lower voltage enables a smaller and more cost-effective power supply for generating the required voltage.

[0022] The object is also achieved by a vehicle as described in the next paragraph.

[0023] A vehicle having a charging device for a traction battery, the charging device having a rectifier and a traction battery connected directly or indirectly to the rectifier, wherein the traction battery is electrically coupled to an active conductor, and wherein the charging device has an above-described compensation device. In a vehicle with electrical coupling, leakage currents occurring inside the vehicle can also be detected outside the vehicle and can trigger fuses of the power supply network. The use of a compensation device is therefore particularly advantageous in this case. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Further details and advantageous developments of the invention are obtained from the exemplary embodiments described below and shown in the drawings, which should not be understood as limiting the invention in any way, and from the preferred embodiments described above. In the drawings:

[0025] Figure 1 An embodiment of a compensation device is shown,

[0026] Figure 2 shows the power supply for compensating current,

[0027] Figure 3 Show Figure 1 An embodiment of the compensation device for an amplifier,

[0028] Figure 4 Show Figure 1 An embodiment of a compensation current measuring device,

[0029] Figure 5 Show Figure 1 An embodiment of a safety device,

[0030] Figure 6 Show Figure 1 An embodiment of the compensation current selection device, and

[0031] Figure 7 Show Figure 1 Application of compensation device in vehicles. DETAILED DESCRIPTION

[0032] Figure 1An embodiment of a compensation device 20 is shown. Five conductors 51, 52, 53, 54 and 55 are provided. In a three-phase power grid, for example, the conductors 51 to 53 can be connected to the external conductors (phases) L1, L2 and L3. The conductor 54 is connected to the neutral conductor N, and the conductor 55 is connected to the protective conductor PE. The conductors required for current conduction (for example, the conductors 51 to 53 for the external conductors L1, L2, L3 of the power supply network) and the conductor 54 for the neutral conductor N of the power supply network are called active conductors. The differential current measuring device measures the differential current of the active conductors 51 to 54. The differential current measuring device 22 can be designed, for example, as a sum current transformer in the form of a winding around the active conductors 51 to 54. When no fault current or leakage current is generated, the sum of the currents passing through the conductors 51 to 54 and thus also the current passing through the winding is zero. In contrast, when, for example, a leakage current flows from phase L1 to the protective conductor PE via the Y capacitor of the power filter, the differential current measuring device 22 obtains the resulting differential current. It is also possible, for example, to measure separately the sum current through the conductors 51 to 53 (on the one hand) and through the conductor 54 (on the other hand), and then calculate the sum or difference between the two values ​​depending on the respective winding direction. The signal I_DIFF of the differential current measuring device 22 is supplied to the signal processing device 24 via the line 23. In the signal processing device 24, for example, an A / D conversion is performed. The signal processing device 24 transmits the corresponding signal to the control device 26 via the line 25. The control device 26 (for example, designed as a microcontroller or a computing unit) calculates a value or signal I_COMP_S for a suitable compensation current based on the determined differential current. This value I_COMP_S is supplied to the amplifier 28 via the line 27, and the amplifier 28 generates the corresponding compensation current I_COMP. For this purpose, the amplifier 28 is connected to the protective conductor 99 in order to enable the current to flow out of or into the protective conductor 99. The amplifier 28 is connected to a compensation current measuring device 30 via a conductor 29. The compensation current measuring device 30 measures the compensation current and outputs a value or signal I_COMP_I to the control device 26 via a conductor 31. The compensation current reaches the safety device 33 via a conductor 32. The control device 26 can control the safety device 33 via a conductor 34 with a signal V_CON. In addition, the safety device 33 is connected to the protective conductor 99 so that the current can flow out of or into the protective conductor 99. The safety device 33 is connected to a compensation current selection device 36 via a conductor 35. The control device 26 can control the compensation current selection device 36 via a conductor 37, via which the signal V_SEL can be transmitted. The compensation current selection device 36 can supply the compensation current to the first feed device 39 via a conductor 38 and / or to the second feed device 41 via a conductor 40.

[0033] A first power supply network identification device 42 is provided to identify the power supply network connected to the conductors 51 to 55 and output a signal V_GRID to the control device 26 via a wire. To this end, the power supply network identification device 42 measures, for example, the voltage on the terminals 51 to 55. This can be carried out, for example, directly in the power supply network identification device 42, or in the control device 26. Therefore, preferably, voltage measuring devices 42, 26 are provided. In a three-phase power grid in Central Europe, for example, the conductors 51 to 55 are connected to the terminals L1, L2, L3, N and PE shown on the left. In the split-phase power grid in the United States, the terminal HOT1 is connected to the conductor 51, the terminal HOT2 with a phase shift of 180° is connected to the conductor 54, and the protective conductor PE is connected to the conductor 55. In a single-phase power grid in Central Europe, either the conductor 51 is connected to L1 and the conductor 54 is connected to N, or the conductor 51 is connected to N and the conductor 54 is connected to L1. Therefore, the assignment relationship is not necessarily unique. An alternative or supplement to the first power supply network identification device 42 is (in Figure 5 ) a second power supply network identification device 45, which is integrated into the safety device 33 in the exemplary embodiment and outputs a signal V_ES to the control device 26 via a conductor 44, as shown in Figure 5 In order to improve safety, a first power supply network identification device 42 and a second power supply network identification device 45 may be provided (see Figure 5 ).

[0034] The feeding devices 39 and 41 may perform feeding, for example, by capacitive coupling or inductive coupling.

[0035] In a supply network with a neutral conductor N, it is preferred to feed in this neutral conductor, because the voltage at the neutral conductor N is usually lower and the supply voltage used for feeding can therefore be lower compared to the voltage on the phases. Preferably, before the supply network L1, N or L1, L2, L3, N, PE or HOT1, HOT2 is connected to the active conductors 51 to 54, the control device 26 causes Figure 5 The switch 84 is placed in the first state. This prevents, for example, the phase voltage from reaching a point further than the safety device 33 when the phase L1 is connected to the terminal 54. The control device 26 preferably only activates the safety device 33 under predefined conditions. Figure 5 The switch 84 is placed in the second state, and these pre-set conditions include:

[0036] - the supply networks L1, L2, L3, N, PE are connected to the active conductors 51 to 54, and

[0037] - Generate signal V_SEL depending on signals V_GRID, V_ES.

[0038] The connection of the supply network first enables the supply network to be identified and only after the generation of the signal V_SEL does it ensure that the correct feed device is selected by means of the compensation current selection device 36 .

[0039] The signal I_COMP_S for the compensation current I_COMP is calculated, for example, by determining the frequency spectrum of the differential current or signal I_DIFF, wherein a frequency range of 20 Hz to 300 kHz may be sufficient, for example. The frequency spectrum contains corresponding amplitudes, and the signal I_COMP_S is generated with a phase shift of 180° (in antiphase) to bring about a corresponding compensation. Other calculations of the integral are also possible.

[0040] Figure 2 A power supply 60 is shown for generating a DC voltage at outputs 63, 64 from a DC voltage at inputs 61, 62. The voltage between the inputs 61, 62 is, for example, 12 V. The voltage at output 63 is, for example, +15 V and the voltage at output 64 is, for example, -15 V. The power supply 60 is connected to a protective conductor 99 in order to enable potential referencing relative to the protective conductor.

[0041] Figure 3 2 shows an embodiment of an amplifier 28. In this embodiment, the amplifier 28 is designed as a differential amplifier and has an operational amplifier 66 having a positive (non-inverting) input 67 and a negative (inverting) input 68 and an output 71. For the supply voltage, the operational amplifier 66 is connected to Figure 2 The terminals 63 and 64 of the power supply 60 are connected. The wire 27 is connected to the positive input terminal 67 via a resistor 69. The negative input terminal 68 is connected to the ground (GND) 98 via a resistor 70. In addition, the negative input terminal 68 is connected to the output terminal 71 via a resistor 72. The output terminal 71 is connected to the wire 29. The amplification factor of the amplifier 28 must be selected depending on the signal I_COMP_S, and an amplification factor of 10 is used in the embodiment.

[0042] However, the following component values ​​are given by way of example and not by way of limitation:

[0043] Resistor 69: 13 kilo ohms

[0044] Resistor 70: 330 ohm

[0045] Resistor 72: 3,300 ohms

[0046] Alternatives for the amplifier shown are digital-to-analog converters or class-D amplifiers.

[0047] Figure 42 shows a compensation current measuring device 30. The conductor 29 with the compensation current I_COMP is connected to a conductor 77 via two parallel-connected resistors 75, 76 (for example, each 100 ohms). A current sensor 78 is arranged on the conductor 77, for example, a magnetic current sensor with a Hall sensor or a current sensor using the magnetoresistive effect. A signal I_COMP_I representing the compensation current I_COMP (the signal is, for example, a voltage signal) is supplied to the conductor 31 via the conductor 31. Figure 1 The control device 26 of FIG. 7 is connected to the terminal 63 of the power supply 60 via the diode 79 and to the terminal 64 of the power supply 60 via the diode 80. The cathode of the diode 79 is toward the terminal 63 and the anode of the diode 80 is toward the terminal 64.

[0048] Resistors 75, 76 serve to limit current, and likewise diodes 79, 80. When the voltage on wire 77 becomes greater than the voltage on terminal 63, current flows toward terminal 63, and when the voltage on wire 77 becomes less than the voltage on terminal 64, current flows from terminal 64 to wire 77. Thus, the voltage on wire 77 is limited to the voltage on terminal 63 or 64.

[0049] The compensation current is then output via the line 32 .

[0050] Figure 5 Safety device 33 is shown. Conductor 32 is connected to switch 84. Switch 84 can enable (first) conductor 32 to be selectively interconnected with (second) conductor 85 or (third) conductor 86 depending on signal V_CON on conductor 34. Interconnection with second conductor 85 can be referred to as first state Z1, and interconnection with third conductor 86 can be referred to as second state Z2. Conductor 32 is connected to protection conductor 99 via Z diode (Zener diode) 82, and conductor 85 is connected to protection conductor 99 via resistor 83. Conductor 32 is connected to conductor 86 via capacitor 89. Conductor 86 is connected to conductor 35 via two PTC resistors 87, 88 connected in parallel.

[0051] The switch 84 is preferably designed as a relay, since a relay has a low resistance in a conductively connected state and has a high isolation resistance and a high cutoff voltage in a non-conductively connected state.

[0052] The Z diode 82 limits the voltage on the wire 32 to a preset value corresponding to the breakdown voltage. When the wire 32 is connected to the wire 85 via the switch 84, the wire 32 is connected to the protective conductor 99 via the resistor 83. The resistor 83 is, for example, 10 ohms. This enables Figure 1The control device 26 performs self-diagnosis in that it outputs a compensation current I_COMP via the amplifier 28, but allows this compensation current to flow in the direction of the protective conductor 99 and does not allow it to flow in the direction of the active conductors 51 to 54. Thus, even in the absence of a mains supply connection, for example Figure 1 In the case of active conductors 51 to 54, a current flow can also be generated for diagnostic purposes. In addition, even when the supply network is connected, the compensation current I_COMP is not coupled into the active conductors L1, L2, L3 or N, and the triggering of the fuse is avoided when performing diagnosis.

[0053] Even if the connecting wires 32, 86 are not connected via the switch 84, the current pulse can reach the wire 32 from the left via the capacitor 89. The magnitude of the voltage is limited by the Z diode 82. The wire 32 is connected to the Figure 1 The control device 26 of the safety device 33 is connected and can output a signal V_ES to the control device 26. The voltage of the signal V_ES enables the measurement of voltage pulses or AC voltages, which can be applied to the conductor 35 and flow to the protective conductor 99 via the resistor 83. In order to evaluate the voltage, a voltage measuring device 33, 26 can be used, such as an A / D converter or a comparator, which is either arranged in the safety device 33 or in the control device 26. It can thus be determined whether the conductor 35 is connected to the neutral conductor N (no voltage fluctuation) or to the phase L1 (AC voltage signal) via the compensation current selection device 36. Therefore, the capacitor 89 and the switch 84 together form the second power supply network identification device 45.

[0054] The PTC resistors 87, 88 form an additional safety measure. At high currents, the PTC resistors 87, 88 heat up and thus their resistance value increases. This achieves additional current limitation at high currents.

[0055] Figure 6 Show Figure 1 Embodiment of compensation current selection device 36 of the present invention. A switch 110 is provided and its input is connected to conductor 35, via which compensation current I_COMP can be supplied. Switch 110 can be controlled by signal V_SEL via conductor 37 and, depending on signal V_SEL, the input of switch 110 can be connected to conductor 38 or to conductor 40. It is also possible to use such a switch which, instead of supplying it separately, can realize the transmission of compensation current I_COMP to both conductors 38, 40.

[0056] Figure 7An embodiment of the use of conductors 51 to 55 with a schematically indicated compensation device 20 in a vehicle 10, in particular in an electric vehicle or hybrid vehicle, is shown. Conductors 51 to 53 (phase conductors or outer conductors), 54 (neutral conductor) and conductor 55 (protective conductor) are connected to a rectifier (AC / DC converter) 100, and two conductors 101 (+) and 102 (-) are provided at the output of the rectifier 100, on which a DC voltage is present. The assembly can thus be used as a charging device 12. Conductor 101 is connected to a protective conductor 99 via a capacitor 103, and conductor 102 is connected to the protective conductor 99 via a capacitor 104. Conductors 101, 102 are connected directly or indirectly (for example via an additional DC / DC converter) to a consumer 105 (for example a traction battery). Capacitors 103, 104 serve as EMC filters or grid filters and are also referred to as Y capacitors or filter capacitors. During operation, current can flow to the protective conductor 99 (PE) via capacitors 103, 104. Since the voltage on the conductors 101, 102 is generated by the current through the active conductors L1, L2, L3 and N, the leakage current to the protective conductor 99 causes a differential current to be generated in the active conductor, which can trigger the fuse or fault current protection switch of the power supply terminal when a preset limit value is exceeded. Common limit values ​​of fuses in power supply networks are, for example, 3.5mA, 10mA or 30mA.

[0057] The compensation device 20 can compensate for the leakage current to such an extent that the fuses of the power supply network are not triggered during normal operation due to exceeding the limit value of the leakage current.

[0058] This is particularly advantageous in charging devices 12 for electric vehicles or hybrid vehicles, which have a galvanic coupling between the DC intermediate circuit 101, 102 and the conductors 51 to 54 or between the consumer 105 and the conductors 51 to 54. Unlike in vehicles with galvanic isolation, which can be the case, for example, in a vehicle with a transformer in the rectifier 100 or the DC / DC converter, in the case of galvanic coupling, leakage currents accumulate and are visible in the supply network. Therefore, the use of the compensation device 20 in vehicles with galvanic coupling is particularly advantageous.

[0059] Of course, various changes and modifications are possible within the scope of the invention.

[0060] The circuits specifically shown may also contain (in addition to the claimed elements) further elements for increasing safety or for other functions. Each of the elements described in the text may form a preferred development and may be used preferably independently.

Claims

1. A compensation device (20) for compensating leakage current, the compensation device (20) comprising a differential current measuring device (22), a power supply network identification device (42; 45), a control device (26), an amplifier (28), a compensation current selection device (36), and a feeding device (39, 41), The differential current measuring device (22) is designed to detect a first signal (I_DIFF) characterizing a differential current of the active conductors (51, 52, 53, 54) and to supply it to the control device (26), The power supply network identification device (42; 45) is designed to generate a second signal (V_GRID; V_ES) characterizing the power supply network (L1, L2, L3, N) connected to the active conductors (51, 52, 53, 54) and to supply it to the control device (26), The control device (26) is designed to generate a compensation preset signal (I_COMP_S) suitable for compensation according to the first signal (I_DIFF) and supply it to the amplifier (28), The amplifier (28) is designed to generate a compensation current (I_COMP) depending on the compensation preset signal (I_COMP_S), The feed device (39, 41) is designed to enable the compensating current to be fed on at least two different active conductors (51, 54). The compensation current selection device (36) is designed to perform a feeding of the compensation current (I_COMP) on at least one of the at least two different active conductors (51, 54) depending on a third signal (V_SEL), And the control device (26) is designed to generate the third signal (V_SEL) as a function of the second signal (V_GRID; V_ES) in order to select at least one active conductor (51, 54) suitable for the connected power supply network for the feed.

2. A compensation device (20) according to claim 1, wherein the power supply network identification device (42; 45) has at least one voltage measuring device and is designed to measure the voltage on at least one of the active conductors (51, 52, 53, 54) by means of the at least one voltage measuring device in order to identify the connected power supply network.

3. A compensation device according to claim 1 or 2, wherein the compensation device has a safety device (33), the safety device has a switch (84), the switch (84) is connected to a first conductor (32) on the input side, the first conductor (32) is connected to the amplifier (28), and the switch (84) is designed to selectively connect the first conductor (32) to a second conductor (85) in a first state (Z1) or to a third conductor (86) in a second state (Z2), wherein the second conductor (85) is connected to a protective conductor terminal (99), wherein the third conductor (86) is connected to the compensation current selection device (36), and wherein the control device (26) is capable of operating the switch (84).

4. The compensation device (20) according to claim 3, wherein the switch (84) is designed as a relay.

5. A compensation device (20) according to claim 3, wherein the control device (26) is designed to enable a functional check, in which the control device controls the switch (84) so ​​that the switch is in the first state (Z1); and in the functional check, the control device (26) supplies the amplifier (28) with a compensation preset signal (I_COMP_S), which causes a compensation current (I_COMP) to check the function of the amplifier (28) without feeding the compensation current by the feeding device (39, 41).

6. The compensation device (20) according to claim 3, wherein before the power supply network (L1, L2, L3, N, PE; L1, N, PE; HOT1, HOT2, PE) is connected to the active conductors (51, 52, 53, 54), the control device (26) places the switch (84) in the first state; and wherein under predetermined conditions, the control device (26) places the switch (84) in the second state, the predetermined conditions comprising: The power supply network (L1, L2, L3, N, PE) is connected to the active conductors (51, 52, 53, 54) and generates the third signal (V_SEL) depending on the second signal (V_GRID).

7. A compensation device (20) according to claim 3, wherein the first conductor (32) is connected to the third conductor (86) via a capacitor (89) so that the pulse generated on the third conductor (86) can be transmitted to the first conductor (32) even in the first state (Z1) of the switch (84).

8. A compensation device (20) according to claim 1 or 2, which has a compensation current measuring device (30), which is designed to measure the compensation current (I_COMP), generate a fourth signal (I_COMP_I) characterizing this compensation current (I_COMP), and supply the fourth signal (I_COMP_I) to the control device.

9. The compensation device (20) according to claim 1 or 2 is designed to: when the power supply network identification device (42; 45) identifies a power supply network (L1, L2, L3, N) with a neutral conductor, control the compensation current selection device (36) so that the compensation current (I_COMP) is fed by the feeding device to the active conductor (51; 54) connected to the neutral conductor (N).

10. A vehicle (10) having a charging device (12) for a consumer (105), the charging device (12) having a rectifier (100) and a consumer (105) connected directly or indirectly to the rectifier (100), the consumer (105) being electrically coupled to an active conductor (51, 52, 53, 54), and the charging device (12) having a compensation device (20) according to one of the preceding claims.

11. The vehicle (10) according to claim 10, wherein the electrical consumer (105) is a traction battery.

12. The vehicle (10) according to claim 10 or 11, wherein an EMC filter (103, 104) is arranged between the rectifier (100) and the consumer (105).

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