DE102007024200A1 - Device for supplying power to the electrical system of a motor vehicle - Google Patents

Abstract

The The invention relates to a device for supplying power to the On-board network of a motor vehicle. It contains an alternator, one of a field winding having exciter circuit and a a plurality of phase windings having first stator winding group having. Furthermore, one connected to the alternator first sub-board provided in which first consumer arranged are and which via a first rectifier arrangement connected to the first stator winding group. Furthermore, a connected to the alternator second Part-board network provided, arranged in which second consumer are. The alternator further includes a plurality Phase winding having second stator winding group, to which a second rectifier via a second Part-board network is connected. Furthermore, the two sub-networks are over a DC-DC converter coupled together.

Description

The The invention relates to a device for supplying power to the Electrical system of a motor vehicle, which has an alternator, one of a field winding having exciter circuit and a a plurality of phase windings having first stator winding group comprising a first sub-electrical system connected to the three-phase generator, in which first consumers are arranged and which over a first rectifier arrangement to the first stator winding group is connected, and connected to the alternator second sub-board network, in which second consumers are arranged, having.

State of the art

To the Vehicle electrical system of a motor vehicle include both low-current consumers as well as high current consumers. Low-current consumers are for example Control units, sensor modules and signal acquisition modules. High current consumers are, for example, the starter, the windscreen heater, a electric steering and a catalyst heating of the vehicle.

The Power supply of such a vehicle electrical system is done using a generator and the vehicle battery. This burden the high current consumers the wiring system to a considerable extent. They cause due high consumer currents Voltage dips, voltage overshoots and increased EMC radiation. For this reason will be all consumers of the electrical system against these faults designed robust. This robust design results in the consumers, both in terms of their own function as well oversized in terms of their own sturgeon involvement are. This need for oversizing is with high costs.

to Avoiding the above-mentioned disadvantages, it is already known to divide the electrical system of a motor vehicle into two sub-networks. The first sub-board network contains the low-current consumers such as control units, sensor modules and signal acquisition modules. These can be due to their limited interference be dimensioned closer, resulting in cost advantages. The second sub-board network contains the high-current consumers. This second subnetwork has larger ones Voltage fluctuations too. The located in this second part of the network Consumers are for these larger voltage fluctuations designed. The second part of the electrical system is for the purpose of its power over a unidirectional DC-DC converter to the first sub-board network connected. It would be desirable to have a power supply of the second sub-board network using its own generator. However, this fails in motor vehicle applications on the limited space in the immediate installation space of the internal combustion engine.

From the DE 198 38 296 A1 An electric power supply system is known. This has a three-phase generator comprising phase windings, which can be connected to a battery and is connected to consumers via rectifier elements and a voltage converter. The battery is connected to one side of the generator's phase windings. The rectifier elements communicate with the other side of the generator phase windings. The battery is part of a first electrical system, which has 12 V consumers. Other consumers that are connectable to the voltage converter are part of a second Bordnet ZES, which has a relation to the rated voltage of the battery higher voltage. The second electrical system contains 42 V consumers.

Advantages of the invention

A Device for supplying power to the electrical system of a motor vehicle with the features of claim 1, in contrast, has several Advantages. So, over a single generator two Subsystem directly supplied, this generator a single Exciter circuit and two stator winding groups isolated from each other having. The installation volume of such a multi-voltage generator is only slightly larger than the installation volume of a conventional clamping generator. Furthermore is only one generator via the V-belt of the motor vehicle drive. By contrast, multigenerator solutions are - insofar as a drive with a V-belt at all possible is - associated with a higher V-belt load and cause higher costs. The two sub-networks may have the same or different nominal voltages. On a powerful DC-DC converter for the Supply of the second sub-board network alone from the first sub-board network can be dispensed with.

Preferably, the two sub-electrical systems are coupled to each other via a bidirectional DC-DC converter. Although this bidirectional DC-DC converter is not required as the main energy supplier of one of the two sub-electrical systems, but can be used in the case of an undervoltage in one of the sub-electrical system to a feed from the other sub-electrical system and in case of overvoltage to a discharge of the current in the other sub-electrical system. Furthermore, the bidirectional DC-DC converter provides a backup power source for each of the two sub-networks If, for example, the stator winding of one of the stator winding assemblies has an interruption, then the supply of the associated sub-electrical system can be effected at least partially via the DC-DC converter depending on the power of the DC-DC converter.

• a) Die Spannung am Ausgang der ersten Gleichrichteranordnung, die der ersten Ständerwicklungsgruppe nachgeschaltet ist, wird über den Strom in der Erregerwicklung geregelt.
• b) Die Spannung am Ausgang der zweiten Gleichrichteranordnung, die der zweiten Ständerwicklungsgruppe nachgeschaltet ist, wird zum einen durch den oben erwähnten Strom durch die Erregerwicklung und zum anderen durch die Einspeisung bzw. Abführung des Stromes über den Gleichspannungswandler bestimmt. Die Regelung der Spannung wird hier aber durch die Höhe des Stromes (Zu- bzw. Abführung) durch den Gleichspannungswandler vollzogen.

Preferably, the voltages of the two sub-systems are regulated as follows:

• a) The voltage at the output of the first rectifier arrangement, which is connected downstream of the first stator winding group, is regulated by the current in the field winding.
• b) The voltage at the output of the second rectifier arrangement, which is connected downstream of the second stator winding group, is determined, on the one hand, by the above-mentioned current through the excitation winding and, on the other hand, by the supply or discharge of the current via the DC-DC converter. The regulation of the voltage is carried out here by the amount of current (supply or discharge) through the DC-DC converter.

Further advantageous properties of the invention will become apparent from the following explanation with reference to the drawing.

drawing

The 1 shows a block diagram of a device for supplying power to the electrical system of a motor vehicle according to an embodiment of the invention.

description

The in the 1 The device shown contains a generator 1 , To this belong an exciter circuit 2 , a first stator winding group 8th , a second stator winding group 12 , a first rectifier arrangement 22 , a second rectifier arrangement 29 and a first voltage regulator 34 ,

The exciter circuit 2 has a transistor 3 and a field winding connected to the collector of this transistor 4 on.

The first stator winding group 8th that with the exciter circuit 2 interacts, consists of three phase windings 5 . 6 and 7 , the form of a star connection are interconnected. The second stator winding group 12 also with the excitation circuit 2 interacts, has three phase windings 9 . 10 and 11 on, which are also interconnected in the form of a star connection.

The outputs of the first stator winding group 8th are realized with a rectifier arrangement realized as a rectifier bridge 22 connected to which diodes 16 . 17 . 18 . 19 . 20 and 21 belong. To the outputs of the second stator winding group 12 is realized as a rectifier bridge second rectifier arrangement 29 connected to which diodes 23 . 24 . 25 . 26 . 27 and 28 belong.

Furthermore, between the output 36 the first rectifier arrangement 22 and the exciter circuit 2 the first voltage regulator 34 switched, which to control the output 36 The DC voltage provided to the first rectifier arrangement is provided. This at the exit 36 Provided DC voltage, which is for example 12 V, serves as a DC supply voltage for a first sub-electrical system 13 , This includes first consumers 14 , which are low-voltage consumers, and a first energy storage 15 at.

At the exit 37 the second rectifier arrangement 29 is a second sub-board network 30 connected. At this exit 37 a DC voltage is provided which serves as a DC supply voltage for the second sub-electrical system 30 serves and is for example 42V. The second sub-board network 30 include high current consumers 31 and a second energy storage 32 at.

The two sub-networks 13 and 30 are via a bidirectional DC-DC converter 33 coupled together. Between the exit 37 the second rectifier arrangement 29 and the bidirectional DC-DC converter 33 is a second voltage regulator 35 connected.

In the apparatus described above, the alternator provides 1 a two-voltage generator at its outputs 36 and 37 provides two DC voltages. As explained in connection with the described exemplary embodiment, these DC voltages may be DC voltages of different sizes. According to an alternative embodiment, at the outputs 36 and 37 of the alternator 1 but also DC voltages of the same size can be provided. These DC voltages are provided by a single generator, which has one excitation circuit and two mutually insulated stator winding groups. The stator winding groups each have three star-shaped interconnected phase windings.

The Both provided by the generator DC voltages are used for Power supply of two different sub-networks. These can - like already executed - with DC voltages the same size or alternatively with DC voltages different sizes are supplied.

For voltage regulation of the two sub-systems, two independent voltage regulators are provided. The first voltage regulator 34 is between the output of the first rectifier arrangement 22 and the exciter circuit 2 switched and changed by the exciter winding 4 flowing excitation current as a function of the output 36 provided DC voltage. The second voltage regulator 35 is for controlling the supply voltage for the second sub-electrical system 30 provided and influenced by the bidirectional DC-DC converter 33 , via which the two sub-networks are coupled together. The second subnetwork 30 experiences in the presence of an undervoltage supply via the DC-DC converter and in the presence of an overvoltage a dissipation of the current through the DC-DC converter in the first sub-electrical system.

Due to the switched between the two sub-networks bidirectional DC-DC converter 33 in each case given a redundancy with respect to the voltage supply of the two sub-network. If, for example, an interruption occurs in one of the stator winding groups of the generator, the voltage supply of the associated sub-board network takes place via the DC-DC converter.

alternative to a two-voltage generator can according to a another embodiment of the invention also a three, four or generally a multi-voltage generator be realized, which three, four or more stator winding groups having. This can be three, four or even more sub-networks be supplied with DC voltages of desired amplitudes. It requires a voltage control system, in which a Control of all sub-systems via a regulation of the excitation current takes place and in which, moreover, a regulation of Supply voltages of the individual sub-network over the provided between the sub-board networks DC-DC converter is made.

The Control interventions can be fixed. alternative In the case of very large deviations, one of the supply voltages of their nominal value also a switch in the sense that the regulation of this different supply voltage by a Control of the exciter current is made and the regulation of other supply voltages using the DC-DC converter he follows.

alternative to a star connection, the windings of the stator winding groups each interconnected in the form of a delta connection be. Another alternative is to wind the windings first stator winding group in the form of a star connection and the windings of the second stator winding group in Form a delta connection with each other.

A Device according to the invention can also do more have as two stator winding groups, each over a bidirectional DC-DC converter coupled together are.

A Another alternative is between the first and the second Partial board network to arrange a unidirectional DC-DC converter. This is advantageous if the base load of the second sub-board network always greater than that of its consumers Current flowing in the second stator winding group at maximum Excitatory current can be induced. The feeding direction of the DC-DC converter runs in this case in the direction of the second sub-board network.

To All this, the present invention provides a device for supplying power to the On-board network of a motor vehicle available, in which the electrical system is divided into several sub-networks and in which by means of a single alternator several independent Supply voltages are generated.

Of the Three-phase generator has a single excitation circuit and several Stator winding groups. These are each about a rectifier arrangement with an output of the generator and connected to the connected sub-network. The space requirement such a multi-voltage generator is only slightly larger as the space requirement of a conventional Einspannungsgenerators. Another advantage of a multi-voltage generator according to the Invention is that over the V-belt of the motor vehicle only one generator needs to be driven, so the V-belt load remains relatively low. According to the present Invention is the main supply of several sub-network each directly from a generator and not using an otherwise needed one powerful, unidirectional DC-DC converter.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 19838296 A1 [0005]

Claims (12)

Device for supplying power to the electrical system of a motor vehicle, comprising - an alternator ( 1 ), which has a field winding ( 4 ) having exciter circuit ( 2 ) and a plurality of phase windings ( 5 . 6 . 7 ) having first stator winding group ( 8th ), - one with the three-phase generator ( 1 ) connected first sub-board network ( 13 ), in which first consumers ( 14 ) are arranged and which via a first rectifier arrangement ( 22 ) to the first stator winding group ( 8th ), and - one with the alternator ( 1 ) second sub-board network ( 30 ), in which second consumer ( 31 ) are arranged, characterized in that - the alternator ( 1 ) a multiple phase windings ( 9 . 10 . 11 ) having second stator winding group ( 12 ) and - the second sub-board network ( 30 ) via a second rectifier arrangement ( 29 ) to the second stator winding group ( 12 ) connected. Apparatus according to claim 1, characterized in that the two sub-networks ( 13 . 30 ) via a bidirectional DC-DC converter ( 33 ) are coupled together. Device according to claim 1 or 2, characterized in that it comprises a first voltage regulator ( 34 ) which is connected between the first rectifier arrangement ( 22 ) and the exciter circuit ( 2 ) is switched. Device according to Claim 2 or 3, characterized in that it comprises a second voltage regulator ( 35 ) which is connected between the second rectifier arrangement ( 29 ) and the DC-DC converter ( 33 ) is switched. Device according to one of the preceding claims, characterized in that at the outputs ( 36 . 37 ) of the two rectifier arrangements ( 22 . 29 ) DC voltages of the same size are present. Device according to one of claims 1-4, characterized in that at the outputs ( 36 . 37 ) of the two rectifier arrangements ( 22 . 29 ) DC voltages of different sizes. Device according to one of the preceding claims, characterized in that the stator winding groups ( 8th . 12 ) each have three or more phase windings, which are interconnected in the form of a star connection. Device according to one of claims 1-6, characterized characterized in that the Ständeiticklungsgruppen respectively have three or more phase windings in the form of a delta connection are interconnected. Device according to one of claims 1-6, characterized characterized in that the stator winding groups respectively have three or more phase windings, wherein the phase windings the first stator winding groups in the form of a star connection and wherein the phase windings of the second stator winding group are connected in the form of a delta connection. Device according to one of the preceding claims, characterized in that they have more than two stator winding groups each having a bidirectional DC-DC converter coupled together. Device according to one of the preceding claims, characterized in that the regulation of the voltage of a first Ständerwicklungsgruppe by the excitation current to the scheme the voltage of the second stator winding group switchable is. Device according to claim 1, characterized in that that the two sub-networks via a unidirectional DC-DC converter are coupled together.