Device for converting electrical energy
Patent Information
- Authority / Receiving Office
- DE · DE
- Patent Type
- Patents
- Current Assignee / Owner
- ASTEMO LTD
- Filing Date
- 2014-01-27
- Publication Date
- 2026-07-09
AI Technical Summary
Existing electric power conversion devices suffer from noise coupling between the inverter and DC-DC converter, leading to increased electromagnetic noise emission and interference with vehicle radios, while conventional noise reduction methods increase manufacturing costs and device size.
The device incorporates a grounded common housing with a capacitor assembly that includes smoothing capacitors and bus bars arranged to minimize noise coupling, using positional relationships and shielding to reduce electromagnetic interference.
This configuration effectively reduces noise coupling between the inverter and DC-DC converter, maintaining a compact design while minimizing electromagnetic noise transmission to the external battery, thus reducing electromagnetic interference.
Abstract
Description
Technical field
[0001] The present invention relates to a device for converting electrical energy, which is housed in a vehicle and which, for example, converts electrical energy, and in particular to the construction of this device. State of the art
[0002] There are already electric vehicles powered by a dynamo-electric machine, such as an electric motor, for example, so-called hybrid vehicles with a dynamo-electric machine in conjunction with an internal combustion engine, and the like. These electric vehicles are generally equipped with a device for converting electrical energy. This device consists of a DC converter, which receives direct current from a high-voltage battery as its power supply and converts the received DC energy into DC energy with a different voltage value, which it then outputs. It also includes an inverter, which receives the DC energy from the DC converter, converts the received DC energy into alternating current energy, and uses this to drive a motor.
[0003] In a device for converting electrical energy with a DC-DC converter and an inverter, it is possible to make the entire device more compact by housing the DC-DC converter and the inverter in a common housing, forming a single module. For example, patent document 1, cited below, describes a compact design for a device in which the smoothing capacitor for the DC-DC converter is located on the input side of the DC-DC converter and the smoothing capacitor for the inverter is located on the input side of the inverter, both housed in a common capacitor housing. List of cited publications Patent publication
[0004] Patent Publication 1: Japanese unexamined patent application with publication number 2007-174760 Summary of the invention Technical problem
[0005] In the aforementioned device for converting electrical energy according to known technology, two systems utilizing different voltage sources are housed in a common casing to reduce the overall size of the device. Specifically, the smoothing capacitor for the DC-DC converter and the smoothing capacitor for the inverter are located close to each other. This results in problems because the noise generated by the switching operations in the inverter is transmitted to the input side of the DC-DC converter, thus increasing the noise reaching the external battery.
[0006] When this transmitted noise is carried along the cable connecting the electrical energy converter to the external battery (generally, the external battery is connected to the converter via a shielded cable), the cable acts as an antenna, increasing the electromagnetic noise emitted into the vehicle and to the outside. This noise is therefore audible in a car radio. As a countermeasure, the noise can be reduced to some extent, for example, by incorporating a filter on the DC-DC converter on the external battery side. However, the effect is not always sufficient. Furthermore, this increases manufacturing costs and makes the device larger.
[0007] The present invention was made in view of these problems with the existing technology, and it is an object of the present invention to provide a device for converting electrical energy which is compact and in which at the same time less of the noise generated by the switching operations of an inverter is transmitted to an external battery. Solution to the problem
[0008] The aforementioned problems are solved, for example, by the embodiments mentioned in the claims. It should be noted that the present invention comprises a number of solutions to these problems.For example, an electrical energy conversion device is provided, comprising a common housing held at ground potential, containing: an inverter circuit unit for converting direct current energy into alternating current energy; a converter circuit unit for boosting the voltage from an external battery and outputting the voltage to the inverter circuit unit, or for reducing a power supply voltage from the inverter circuit unit and outputting the voltage to the external battery; and a capacitor assembly comprising a smoothing capacitor element connected to the power supply voltage side of the inverter circuit unit and a smoothing capacitor element connected to the power supply voltage on the battery side of the converter circuit unit, and accommodating the elements together.In the electrical energy conversion device, the capacitor assembly, together with the number of smoothing capacitor elements, comprises a negative electrode terminal rail connected to both the negative electrode of the inverter circuit unit and the electrode on the negative side of the converter circuit unit; a first positive electrode terminal rail connected to the positive electrode of the inverter circuit unit and to one capacitor of the smoothing capacitors; and a second positive electrode terminal rail connected to the positive electrode on the battery side of the converter circuit unit and to the other capacitor of the smoothing capacitors.The first positive electrode terminal is located at a point opposite one main side of the negative electrode terminal, and the second positive electrode terminal is located at a point opposite the other main side of the negative electrode terminal and away from the first positive electrode terminal. Advantageous effects of the invention
[0009] The present invention makes it possible to reduce the noise coupling between an inverter device and a DC converter device, so that it is possible to create a device for converting electrical energy that is compact and in which at the same time the noise transmitted to an external battery due to the noise generated by the switching operations of the inverter is reduced. Brief description of the drawings
[0010] Fig. Figure 1 is a circuit diagram of an exemplary schematic setup of a motor drive system with a device for converting electrical energy in an embodiment of the present invention.
[0011] Fig. Figure 2 is a representation of the schematic structure of the device for converting electrical energy in the embodiment of the present invention.
[0012] Fig. Figure 3 is a partially separated, perspective view of the arrangement of terminal rails in a capacitor assembly of the electrical energy conversion device.
[0013] Fig. 4 is a section view (a section view along line AA' in the Fig. 2) the internal structure of the capacitor assembly of the electrical energy conversion device.
[0014] Fig. 5 is a section view (a section view along line AA' in the Fig. 2) the internal structure of a capacitor assembly of a device for converting electrical energy in another embodiment of the present invention.
[0015] Fig. 6 is a section view (a section view along line AA' in the Fig. 2) the internal structure of a capacitor assembly of a device for converting electrical energy in a further embodiment of the present invention. Description of embodiments
[0016] In the following, embodiments of the present invention are described in more detail with reference to the accompanying drawings.
[0017] The Fig. Figure 1 shows a circuit diagram for a schematic setup of a motor drive system with a device for converting electrical energy according to an embodiment of the present invention. As shown in the drawing, the basic setup comprises a device for converting electrical energy with an external battery. 1 , which supplies direct current energy, to a converter 10 and an inverter 40 , a motor generator 60 , which uses the energy from the device for converting electrical energy to deliver power or generate electrical energy (hereinafter simply referred to as the “motor”), and a control circuit board 80For controlling and monitoring the electrical energy conversion device. This motor drive system is intended, for example, for an electric vehicle such as a hybrid car or an electric car, and the electrical energy conversion device is used to perform the drive operation and the regeneration operation of the motor.
[0018] In this motor drive system, the converter increases 10 During drive operation, the DC voltage of the external battery 1 , which represents a rechargeable and dischargeable DC power supply, to a DC voltage with a different value and outputs this voltage to the inverter 40 off. The inverter 40 It converts the direct current energy into alternating current energy using a control system with pulse width modulation (PWM) and supplies the alternating current energy to the motor. 60 off. The engine 60The alternating current energy is used to rotate the rotor inside the motor, which is the load, and thereby drives the vehicle's wheels. In this case, the motor is... 60 a three-phase AC motor.
[0019] During regeneration mode, the engine 60 AC energy generated by the inverter 40 converted into a direct current voltage, which is fed to the converter 10 is supplied. The converter 10 reduces the value of the DC voltage and outputs the DC voltage to the external battery 1 from which it loads.
[0020] As in the Fig. The converter shown in section 1 includes the described converter. 10 and the inverter 40 Semiconductor modules 13 and 43 with switching elements such as IGBTs, and the switching of the switching elements such as the IGBTs of the modules is done with control signals from the control circuit board. 80 The control circuit board80 controls the switching of the semiconductor modules based on signals from an external system not shown.
[0021] The following section will first describe the exact structure of the converter. 10 described and then the two operating states of the converter, that is, the voltage boosting operation and the voltage reduction operation. <Aufbau und Betrieb des Konverters>
[0022] As in the Fig. As shown in Figure 1, the converter includes 10 the semiconductor module 13 , a reactor 14 and a converter smoothing capacitor C1. The semiconductor module 13 It comprises two switching elements Qa0 and Qb0 and diodes Da0 and Db0, each connected in parallel between the collectors and emitters of the switching elements Qa0 and Qb0. The output end of the converter (the positive electrode side of the inverter) 40 ) is connected to the collector side of the switching element Qa0, and one end of the reactor14 and the collector side of the switching element Qb0 is connected to the emitter side. The other end of the reactor 14 is connected to the positive electrode side of the external battery 1 connected, and the emitter side of the switching element Qb0 is connected to a negative electrode terminal rail. 31 (the negative electrode side of the external battery) 1 ) tied together.
[0023] The converter 10 includes a voltage boost function that increases the value of the DC voltage from the external battery 1 converts it into a DC voltage value that is higher than the first-mentioned value, and sends the DC voltage to the inverter. 40 off. The converter 10 It also includes a voltage reduction function that adjusts the value of the DC voltage supplied by the inverter. 40 to the converter 10The output voltage is converted into a DC voltage value that is lower than the output DC voltage value, and the generated DC voltage is then used in the regeneration mode of the motor. 60 to the external battery 1 away.
[0024] The following describes the voltage boost operation of the converter. 10 described. In the converter 10 The switching element Qb0 is powered via the external battery when it is switched on. 1 and the reactor 14 a conduction path between the positive electrode side and the negative electrode side of the external battery 1 trained and temporarily in the reactor 14 Energy is stored due to the direct current flowing through the circuit. When the switching element Qb0 is switched from on to off in this state, an inverter smoothing capacitor C4 is connected via the diode Da0 to the capacitor in the reactor. 14The stored energy is recharged. During charging, the output voltage of the converter can vary. 10 be higher than the input voltage of the converter 10 It should be noted that in voltage boost mode, the switching element Qa0 is always off. The above description describes operation as a voltage boost converter.
[0025] The voltage reduction mode of the converter will now be activated. 10 described. If in the converter 10 When the switching element Qa0 is in the on state, a conduction path is formed that connects the inverter smoothing capacitor C4 and the reactor. 14 with the positive electrode side of the external battery 1 connects, so that the engine is in regeneration mode 60 Energy stored in the inverter smoothing capacitor C4 during charging of the external battery 1 temporarily in the reactor 14is stored. If the switching element Qa0 is switched off in this state, a conduction path is formed that connects the reactor. 14 and the external battery 1 connects to diode Db0, so that it is temporarily in the reactor 14 The stored energy causes a charging current to flow to the external battery. The voltage value at the external battery 1 During regeneration, the ratio of the on-time to the on-off cycle of the switching element Qa0 can be controlled, so that the converter 10 It also serves as a voltage reduction converter. It should be noted that in voltage reduction mode, the switching element Qb0 is always off. Furthermore, the external battery side of the converter... 10The converter smoothing capacitor C1 is connected. The converter smoothing capacitor C1 absorbs the ripple generated when switching elements Qa0 and Qb0. Additionally, the converter smoothing capacitor C1 absorbs the ripple in the signal from the external DC battery. 1 the converter 10 supplied current and stabilizes the supplied current.
[0026] The assembly of the inverter will now begin. 40 more precisely described. <Aufbau und Betrieb des Inverters>
[0027] The inverter 40 The semiconductor module includes 43 and the inverter smoothing capacitor C4. The semiconductor module 43 includes switching elements Qa1, Qa2, Qa3, Qb1, Qb2 and Qb3 and diodes Da1, Da2, Da3, Db1, Db2 and Db3.
[0028] The diodes are connected in parallel to the individual switching elements; Qa1 is connected to Da1, Qa2 to Da2, Qa3 to Da3, Qb1 to Db1, Qb2 to Db2 and Qb3 to Db3.
[0029] The positive inverter electrode connection rail 41 is connected to the collector side of the switching elements Qa1, Qa2 and Qa3. On the other hand, the negative electrode connection rail is 31 The emitter side of switching elements Qb1, Qb2, and Qb3 is connected to the motor. The emitter side of switching elements Qa1, Qa2, and Qa3 and the collector side of switching elements Qb1, Qb2, and Qb3 are each connected to the motor. 60 connected; Qa1 and Qb1 are connected to the U-phase, Qa2 and Qb2 to the V-phase, and Qa3 and Qb3 to the W-phase.
[0030] The inverter 40 controls the engine 60 on, wherein the switching on and off of the switching elements Qa1, Qa2, Qa3, Qb1, Qb2 and Qb3 according to the converter 10The output direct current is controlled and connected to the motor. 60 A three-phase alternating current is output, in which the phases of the alternating current flowing through the motor are offset by an angle of 120° in the U, V and W phases.
[0031] The inverter smoothing capacitor C4 is connected to the output side of the converter. 10 and the input side of the inverter 40 connected. The inverter smoothing capacitor C4 absorbs the ripple that occurs when the semiconductor module switches. 43 This is created. Furthermore, the inverter smoothing capacitor C4 smooths the output voltage at the voltage boost converter. 10 , so that the inverter 40 A stabilized direct current is supplied. <filter>
[0032] As in the Fig. As shown in 1, the converter is included. 10 and the inverter 40 Filter capacitors C2, C3 and C5. C2 is electrically connected to the positive electrode of the converter. 10 connected, C5 electrically to the positive electrode of the inverter 40 and with ground and C3 electrically with the negative electrode and ground. The capacitors are intended to reduce common-mode noise through the positive and negative electrodes and noise from the external battery. 1 as well as the noise from the converter 10 and inverter 40 to ground, so that there is no common-mode noise to the external battery 1 is transmitted. The capacitors also prevent common-mode noise from the external battery. 1 to the converter 10 is transferred.
[0033] As also in the Fig. As shown in Figure 1, in the device for converting electrical energy, both at the converter 10 as well as at the inverter 40 Filter capacitors are provided. Since the negative electrode connection rail 31 of the inverter 40 electrically with the converter 10 When connected, the filter capacitor C3 for the negative electrode consists of a single capacitor, which also serves as a capacitor for the converter. 10 as well as a capacitor for the inverter 40 This represents a reduction in size. However, for selecting the capacitance values for the filter capacitors of the individual systems, it is also acceptable that the filter capacitor C3 connected to the negative electrode is not a common capacitor, but rather connected to the converter. 10 and the inverter 40 is divided up.
[0034] The Fig. Figure 2 shows an example (a first example) of the construction of the device for converting electrical energy according to the present invention. As shown in the Fig. The converter shown in section 2 is... 10 (the converter smoothing capacitor C1 and the semiconductor module 13 ), the inverter 40 (the inverter smoothing capacitor C4 and the semiconductor module 43 ) and the filter capacitors C2, C3 and C5 in a common housing (a housing at ground potential) 101 arranged so that the device for converting electrical energy can be designed compactly. In the present case, the housing consists of 101 made of a conductive material, such as metal (for example, aluminum). The casing 101 It therefore also has a shielding function, preventing electromagnetic noise from escaping from the electronic components inside the housing and preventing electromagnetic noise from entering the space containing the electronic components from the outside. The housing 101 It is electrically connected to ground on the side of the vehicle (for example, to the body) and serves as an electrical ground for the device for converting electrical energy.
[0035] Although it is not shown in the drawing, the housing 101 a passage through which cooling water is passed, so that the converter 10 and the inverter 40 inside the case 101 They can be cooled with the cooling water passed through the passage.
[0036] The following will be based on the Fig. 3 and Fig. 4. The construction of a capacitor assembly for the device for converting electrical energy is described in more detail in the present example; that is, details for the capacitors and the terminal rails in the component are described in more detail. <kondensator-baugruppe>First example
[0037] In this example, as in the Fig. 3 and Fig. Figure 4 shows a number of film capacitors (in other words, the converter smoothing capacitor C1, the inverter smoothing capacitor C4, and the filter capacitors C2, C3, and C4) and parts of the conductive plates electrically connected to the film capacitors (a positive converter electrode terminal rail). 11 , a negative electrode connection rail 31 and a positive inverter electrode connection rail 41 ) in a common capacitor assembly 90 (see Fig. 4) which incorporates these capacitor components C1, C2, C3, C4, and C5 into a single component. This allows the capacitor components to be housed compactly, and the entire electrical energy conversion device can be designed to be small. Furthermore, the number of parts can be reduced, thus improving the handling of the device components.
[0038] From the Fig. 3 also shows that the conductive plates of the positive converter electrode connection rail 11 , the negative electrode connection rail 31 and the positive inverter electrode connection rail 41 Elements in plate form (rail form) made of an electrical conductor such as copper, and that between the positive converter electrode connection rail 11 and the negative electrode connection rail 31 and between the negative electrode connection rail 31 and the positive inverter electrode connection rail 41 plate-shaped elements 32 and 33 are arranged from an insulating material, providing electrical insulation between the terminal bars. In these drawings, “•” denotes an electrical connection point, and “o” denotes a through-hole without an electrical connection.
[0039] In other words, as shown in the capacitor assembly... 90 The converter smoothing capacitor C1 is electrically connected to the negative electrode terminal rail. 31 and the positive converter connection rail 11 connected, and the inverter smoothing capacitor C4 is electrically connected to the negative electrode terminal rail. 31 and the positive inverter connection rail 41 connected. As in the Fig. Figure 1 shows the negative electrode connection rail. 31 of the inverter 40 electrically also with the converter 10 connected and used as a common conductive plate.
[0040] As described, in the example device for converting electrical energy, the capacitor assembly is used to reduce the size of the device. 90 a setup is used in which the positive electrode connection rails 11 and 41 The two systems with different voltage sources are arranged close to each other. Capacitive or inductive noise coupling occurs between the positive electrode terminals. 11 and 41 is increased by the switching processes in the semiconductor module 43 The resulting switching noise is fed to the input side of the converter (the positive converter electrode connection rail). 11 ) transferred, thereby transferring the data to the external battery 1 Transmitted noise increases. Typically, the external battery... 1 for example, via a shielded cable and the like to the converter 10 connected. If the noise transmitted to the external battery returns to the electrical energy conversion device via a path other than the shielded cable, for example via the ground plane of the vehicle body, electromagnetic noise is emitted from this electrical current loop, which can, for example, interfere with a radio located in the vehicle.
[0041] To access the external battery 1 To reduce transmitted noise (for noise reduction), attempts can be made to reduce noise coupling by the arrangement of the connection rails of the two systems, or attempts can be made to reduce the noise transmitted to the external battery by means of the positional relationships of the connections between the filter capacitors C2, C3 and C5 and the feed points. 12 to prevent damage from the external battery. However, as already described, this results in problems with increased manufacturing costs and the larger size of the device.
[0042] Therefore, in the present invention, the device for converting electrical energy, and in particular the capacitor assembly, is used. 90 The device is provided with a structure that prevents the coupling of switching noise from the switching operations of the semiconductor module. 43 to the positive converter electrode connection rail 11 through the positive inverter electrode connection rail 41 This is reduced. The following section describes this structure in more detail.
[0043] This is done as in the Fig. Figure 4 shows the positive converter electrode connection rail. 11 arranged at a location corresponding to a main surface of the negative electrode connection rail 31 opposite, and the positive inverter electrode connection rail 41 is positioned at a location opposite the other main surface of the negative electrode connection rail. 31 opposite. The electromagnetic coupling between the positive converter electrode connection rail 11 and the positive inverter electrode connection rail 41 is thus connected to the negative electrode terminal rail 31 interrupted, so that the noise coupling decreases.
[0044] The following describes the positional relationships of the connections between the filter capacitors C2, C3 and C5 and the feed points. 12 described by the external battery.
[0045] As in the Fig. As shown in 1, the converter includes 10 and the inverter 40 The filter capacitors C2, C3, and C5. In other words, the filter capacitors C2, C3, and C5 divert the common-mode noise to ground before the common-mode noise transmitted via the positive and negative electrodes reaches the external battery. 1 is transmitted, whereby the filter capacitors prevent noise from being transmitted to the external battery.
[0046] In this embodiment, the common filter capacitor C3 is therefore preferably located very close to the feed points on the negative electrode side. 12 arranged by the external battery, as described in the Fig. 4 is shown. With this arrangement, the semiconductor module 13 generated noise and that in the semiconductor module 43 The noise generated by the capacitor C3 is reduced before it reaches the external battery. 1 If, on the other hand, the connection position of the negative electrode connection rail is reached. 31 with the filter capacitor C3 for the negative electrode in the capacitor assembly 90 the position between the feed points 12 from the external battery and the semiconductor module 13 If selected, the switching noise from the semiconductor module will be reduced. 13 removed by the filter capacitors C2 and C3 before it reaches the external battery, the ESL (equivalent series inductance) of filter capacitor C3 for the negative electrode with respect to switching noise from switching in the semiconductor module 43 However, this increases and thus the filtering effect caused by the filter capacitor C3 decreases, so that it is not possible to achieve the intended purpose of the capacitor C3.
[0047] Preferably, the filter capacitor C2 is also arranged on the positive electrode side of the converter, close to C3. The reason for this is that if the filter capacitors C2 and C3 are arranged separately, for example, if the filter capacitor C2 is located beyond the connection point of C3 with the negative electrode terminal, the filter capacitor C2 will not function correctly. 31 closer to the semiconductor module 13 The noise propagated via the negative electrode terminal rail is arranged so that, after passing through capacitor C2 between the positive electrode terminal rail and the negative electrode terminal rail between the connection points of the filter capacitors C2 and C3, it is coupled into the positive electrode terminal rail before being reduced at capacitor C3.
[0048] As described above, the example thus comprises a setup for reducing the coupling of switching noise, generated by the switching operations of the semiconductor module in the capacitor assembly, into the positive converter electrode terminal. However, the inventors of the present invention have also discovered that, in addition to the setup for reducing noise coupling, the propagation of noise to the external battery can be further reduced by decreasing the various types of noise coupling, including capacitive or inductive coupling between the positive inverter electrode terminal and the capacitor, and between the positive converter electrode terminal and the capacitor within the capacitor assembly—that is, by reducing the spatial propagation of the noise coupling. The setup of a capacitor assembly for achieving this reduction is described below using a second and third example. Second example
[0049] The Fig. Figure 5 shows the structure of a capacitor assembly. 90 In a second example, as shown in the first example, there is an additional component between capacitor C3 and capacitor C5 in the capacitor assembly. 90 a slot-shaped space is provided, into which a shielding wall is installed. 102 is used, which is at the same potential (the ground potential) as the housing 101 In this setup, the switching noise emitted by capacitor C4 and that from switching the inverter is 40 is caused by the shielding wall 102 blocked, so that it is possible to eliminate the noise coupling between the positive electrode connection rails of the converter. 10 and the inverter 40 to reduce further. Third example
[0050] The Fig. Figure 6 shows the structure of a capacitor assembly. 90 In a third example, the capacitor assembly is similar to the first example. 90 The smoothing capacitor components (C1 and C4) of the two systems are arranged, and the negative electrode connection rail is designed as a flat plate. However, as in the Fig. Figure 6 shows the components arranged such that the negative electrode connection rail 31 is bent and that the orientations of the smoothing capacitors C1 and C4 of the two systems, which are connected to the respective positive electrode terminals, point in opposite directions. The negative electrode terminal 31 is thus positioned between the two smoothing capacitor cells, so that the output from the inverter smoothing capacitor C4 and from the switching of the inverter 40 switching noise caused by the negative electrode connection rail 31 is interrupted. Furthermore, the distance between the two positive electrode connection rails is 11 and 41 The height of the capacitor cells in both systems is increased, making it possible to utilize the inverter. 40 into the converter 10 to reduce coupled-in noise and to connect to the external battery 1 The transmitted noise decreases.
[0051] In the examples of the present invention, the description was given for a vehicle system for driving a single motor as an example of a motor drive system with a device for converting electrical energy, comprising a converter and an inverter in a common housing. However, the present invention is not limited to these examples. The present invention can be adapted to various systems, for example, to a system with a number of inverters connected in parallel at the output side of the converter. 40 are connected to operate a number of motors. The same effects will occur in this case as well.
[0052] Furthermore, the foregoing embodiments can be applied independently or in combination. This allows the effects of the embodiments to be obtained independently or multiplied. Moreover, the present invention is not limited to the above embodiments, as long as their features are not restricted. Reference symbol list 1 external battery 10 converters 11 positive converter electrode connection rail 12. Supply point from the external battery 13 Converter semiconductor module 14 Reactor 31 common negative electrode connection rail 40 Inverter 41 positive inverter electrode connection rail 43 Inverter semiconductor module 60 Motor generator 80 Control circuit board 90 Capacitor assembly 101 Housing (housing at ground potential) 102 Shielding wall C1 Converter smoothing capacitor C2 positive converter filter capacitor C3 filter capacitor on the negative electrode side C4 Inverter Smoothing Capacitor C5 positive inverter filter capacitor Qa0, Qa1, Qa2, Qa3, Qb0, Qb1, Qb2, Qb3 Switching element Da0, Da1, Da2, Da3, Db0, Db1, Db2, Db3 diode < / filter>
Claims
[1] Device for converting electrical energy with a common housing at ground potential for accommodating an inverter circuit unit for converting direct current energy into alternating current energy; a converter circuit unit for increasing the voltage of an external battery and outputting the voltage to the inverter circuit unit, or for reducing a power supply voltage from the inverter circuit unit and outputting the voltage to the external battery; and of a capacitor assembly comprising a smoothing capacitor element connected to the power supply voltage side of the inverter circuit unit and a smoothing capacitor element connected to a power supply voltage on the battery side of the converter circuit unit, wherein the assembly accommodates the elements together, the capacitor assembly comprises the following number of smoothing capacitor elements: a negative electrode connection rail that is connected to the negative electrode of the inverter circuit unit and to the negative electrode side of the converter circuit unit; a first positive electrode connection rail, which is connected to the positive electrode of the inverter circuit unit and to a capacitor of the smoothing capacitors; and a second positive electrode terminal rail, which is connected to the positive electrode on the battery side of the converter circuit unit and to the other capacitor of the smoothing capacitors; wherein the first positive electrode terminal is located at a position opposite a main side of the negative electrode terminal; and wherein the second positive electrode terminal rail is located at a position opposite the other main side of the negative electrode terminal rail and away from the first positive electrode terminal rail. [2] Device for converting electrical energy according to claim 1, wherein the first positive electrode connection rail and the smoothing capacitor connected to the inverter circuit unit and the second positive electrode connection rail and the smoothing capacitor connected to the converter circuit unit are arranged in the capacitor assembly such that the spatial propagation of coupled noise is low. [3] Device for converting electrical energy according to claim 2, wherein a slot section is provided in a part of the capacitor assembly between the smoothing capacitor connected to the inverter circuit unit and the smoothing capacitor connected to the converter circuit unit; wherein a shielding wall is inserted into the slot section, which consists of a part of the common housing at ground potential. [4] Device for converting electrical energy according to claim 2, wherein the negative electrode connection rail is arranged such that the space in the capacitor assembly is divided into a number of spaces; wherein the smoothing capacitor connected to the inverter circuit unit is located in one room and the smoothing capacitor connected to the converter circuit unit is located in another room. [5] Device for converting electrical energy according to claim 1, comprising a first filter capacitor, which is electrically connected between the first positive electrode terminal rail and the common housing at ground potential; and with a second filter capacitor, which is electrically connected between the negative electrode terminal rail and the housing, the second filter capacitor is connected near a feed point from the external battery to the negative electrode terminal rail in the capacitor assembly. [6] Device for converting electrical energy according to claim 5, comprising a third filter capacitor which is electrically connected between the second positive electrode terminal and the common housing at ground potential, wherein the third filter capacitor is connected to the second positive electrode terminal in the capacitor assembly near a supply point from the external battery.