Method for supplying electrical energy to motor vehicles, motor vehicle and supply system

Abstract

Method for supplying electrical energy to motor vehicles (1) by means of a supply system (5), wherein the supply system (5) has at least one substation (4) with associated overhead lines (3) and the motor vehicles (1) have current collectors (2) for contacting the overhead lines (3), characterized in that the motor vehicles (1) notify the substation (4) of their future or current presence in the area of the substation (4), whereby the substation (4) or a higher-level control center (10) determines a maximum power for each individual motor vehicle (1) that the respective motor vehicle (1) may draw from or feed into the substation (4), whereby the determined maximum power is communicated to the respective motor vehicle (1) by the substation (4) or the control center (10), and the motor vehicles (1) additionally transmit further information to the substation (4) or the control center (10), wherein a priority is determined from the further information, which priority is taken into account in the allocation of services, wherein, within the framework of a payment or reward system, a motor vehicle (1) which has previously waived an allocated service withdrawal is assigned a higher priority via bonus points.

Description

The invention relates to a method for the electrical energy supply of motor vehicles by means of a supply system, wherein the supply system has at least one undercarriage with associated overhead lines, a motor vehicle with current collectors for contacting overhead lines, and a supply system with at least one undercarriage and overhead lines.It is known to design road-guided motor vehicles, in particular trucks, with current collectors which then draw electrical energy from overhead lines. In this case, DC voltage is typically used, the voltage being, for example, 600 V to 1200 V. It is also known that the supply system for the overhead lines has sub-units which feed energy, for example, every 3 to 5 km. It is to be ensured that the performance limits of a lower structure are not exceeded. If power is drawn, a current flows via the overhead lines, which results in a voltage drop. The larger the current, the larger the voltage drop. In this case, the voltage drop is also greater the farther away from the feed point of the lower unit the current is drawn.One possible solution is that the motor vehicles record the voltage position on the overhead lines and adapt their power extraction as a function of the voltage position and adjust it in the extreme case. The same applies to a conceivable power supply if, for example, a motor vehicle wishes to feed back braking energy. A disadvantage is that motor vehicles which are far from the feed point of the undercarriage may no longer be able to draw energy because in these motor vehicles the voltage position is too low.According to DE 196 54 960 A1, a hierarchically constructed process control system with three levels is used, in which the master computer carries out coordination of departure and braking processes from the vehicles located on the route in the control mode. The master computer processes the vehicle data and the information transmitted from the control devices of the substations in conjunction with stored information and mathematical models according to a predefined algorithm and performs an optimization of the driving regime.DE 10 2011 085 776 A1 describes a system for the traffic control of electrically driven vehicles in a road network. In this case, the vehicles can be coupled to a overhead line network arranged on the road side for energy transmission during travel. The overhead line network has feed sections which are supplied separately from one another and have load limits which can be designed. The system further comprises prediction means for predicting a load demand in a feed section, influencing means for influencing a load pick-up of vehicles in the feed section, and control means for evaluating the predicted load demand with respect to the load limit of the feed section and for selecting control interventions, which may be required, for influencing means. As a result, a route network arranged on the road side, to which road vehicles of the individual traffic can be coupled for energy transmission during travel, can be operated within the designed load limits.The invention is based on the technical problem of improving a method for the electrical energy supply of motor vehicles and of creating motor vehicles suitable for this purpose and a supply system.The solution of the technical problem results from a method with the features of claim 1, a motor vehicle with the features of claim 8 and a supply system with the features of claim 9.The method for the electrical energy supply of motor vehicles takes place by means of a supply system, wherein the supply system has at least one undercarriage with associated overhead lines and the motor vehicles have current collectors for contacting the overhead line. The motor vehicles communicate their future or current presence to the sub-unit in the region of the sub-unit, wherein the sub-unit or a higher-order control center for the individual motor vehicles each determines a maximum power which the respective motor vehicle is allowed to draw or feed to the supply system, wherein the determined maximum power is communicated to the respective motor vehicle by the sub-unit or the control center. The sub-unit or the control center knows the performance limits of the sub-unit and can distribute them accordingly, since the number of motor vehicles is known. In the simplest case, the power is distributed uniformly.By the additional knowledge of the position of the motor vehicles, it can then on the one hand already be taken into account during the allocation that soon additional motor vehicles enter the area of the undercarriage (which means an increased power requirement) and how much power loss must additionally be taken into account on the basis of the distance from the feed point. The communication between the motor vehicles and the undercarriage is preferably effected wirelessly, for example by means of a suitable radio interface.In one embodiment, the assigned maximum power of the motor vehicles is dynamically adapted, i.e. the assigned power can vary when driving under the overhead line.In a further embodiment, the motor vehicles communicate their actually absorbed or emitted power to the undercarriage. For example, it may happen that a motor vehicle draws less power because, for example, there is no high energy requirement due to a fully charged battery and a low speed. In this case, the subwork may assign the remaining power to other motor vehicles.In a further embodiment, the motor vehicles record the voltage position on the overhead lines and communicate these to the undercarriage. This improves the determination of the currently drawn power, since the current flowing via the overhead lines can be determined in this way, so that the additional power loss at the overhead lines can be determined more accurately.In a further embodiment, the motor vehicles additionally transmit a power demand and / or further information to the substation or the control center, wherein a priority is determined from the power demand and / or the further information, which priority is taken into account in the power assignment. For example, a motor vehicle may have an increased power requirement due to heavy charging and / or a highly discharged battery, such that its power assignment is increased. Other information that can influence the priority can be, for example, whether the motor vehicle is a refrigerated vehicle, a hazardous vehicle or a rescue vehicle. Alternatively or additionally, a payment or reward system can be implemented, so that, for example, a motor vehicle has previously dispensed with an assigned power draw, is assigned a higher priority via bonus points. A further piece of information can be, for example, that motor vehicles are driving in the platoon. In order to optimize the traffic flow, a higher priority can be assigned to the motor vehicles of the platoon.In a further embodiment, the supply system has at least two sub-units, wherein the maximum power is allocated by the first sub-unit as a function of a state in a subsequent second sub-unit. For example, the assigned power at the end of the first sub-assembly can be reduced (which minimizes the power loss) if it is ensured that the motor vehicle can again be sufficiently supplied with energy when driving into the second sub-assembly.The motor vehicle having current collectors for contacting overhead lines and a control device for at least one converter, which is designed to control the energy flow through the converter, has a communication interface. The communication interface is designed in such a way as to communicate with a sub-unit and / or a central unit of sub-units, wherein the control device is designed in such a way as to actuate the converter in such a way that a maximum power transmitted by the sub-unit or the central unit is not exceeded. With regard to the further embodiments, reference is made to the preceding explanations. The converter can be, for example, an inverter, a DC / DC converter or a combined inverter with DC / DC functionality. Furthermore, the motor vehicle can be designed in such a way that, in the absence of messages from the undercarriage or from the control center, the power is drawn or output as a function of the voltage position of the overhead lines. As a result, the motor vehicle can also be used in sub-units not according to the invention or this backup prevents the sub-unit from being loaded too heavily in the event of a communication disruption.The supply system having at least one undercarriage and overhead lines has at least one communication interface which is designed to receive information from motor vehicles, wherein the supply system is designed to determine maximum powers for the motor vehicles and to transmit them to them. The supply system provides a direct voltage.The invention is explained in more detail below with reference to a preferred exemplary embodiment. The figures show: FIG. 1 shows a motor vehicle with current collectors, FIG. 2 shows a schematic block diagram of a supply system with motor vehicles, and FIG. 3 shows a schematic block diagram of a motor vehicle.FIG. 1 schematically shows a motor vehicle 1 having two current collectors 2 for making electrical contact with two overhead lines 3. The overhead lines 3 carry a DC voltage of, for example, 500 V to 1200 V, the voltage supply of which takes place by way of substations 4 (see also FIG. 2 ) which are part of a supply system 5.FIG. 2 schematically shows such a supply system 5. The supply system 5 comprises a first sub-assembly 4 and a second sub-assembly 4, wherein the second sub-assembly 4 is arranged downstream of the motor vehicles 1 in the direction of travel F. Each substation 4 has a mains connection 6 and an inverter 7 in order to convert the alternating voltage of the mains into a desired direct voltage for the overhead lines 3. The overhead lines 3 of different sub-structures 4 can be mechanically connected to one another by insulators 8 or else arranged at a distance from one another, with the result that electrical interactions of the sub-structures 4 with one another are prevented. Furthermore, each sub-unit 4 has at least one communication interface 9 for communicating with the motor vehicles 1 and a control center 10 of the supply system 5.The motor vehicles 1 transmit their position to the undercarriages 4, in the area of which they are located or in the area of which the motor vehicles 1 will be driven in promptly. In the illustrated state according to FIG. 2, three motor vehicles 1 are currently located in the region of the first sub-unit 4 and one motor vehicle 1 is located in the region of the second sub-unit 4. One motor vehicle 1 is located shortly before the first sub-unit 4. In addition to the presence, the motor vehicles 1 transmit their position, their power requirement and further data. The sub-units 4 can now locally determine themselves or else the central unit 10 can centrally determine maximum powers for each motor vehicle 1, which said sub-unit can draw said maximum power from the respective sub-unit 4. These maximum powers determined are then transmitted to the motor vehicles 1 via the communication interfaces 9.For this purpose, the motor vehicles 1 likewise have communication interfaces 11, wherein the transmitted maximum power is transmitted to a control device 12 which correspondingly actuates a converter 13 (see also FIG. 3 ). The converter 13 converts the voltage from the overhead lines 3 into voltages for an electric motor 14 and / or a battery 15. This data D can be, for example, position data of the motor vehicle 1, type of the motor vehicle 1 (cargo, rescue vehicle) or a power demand. This data D and the actual power extraction of the converter 13 are transmitted back to the communication interface 9 of the substations 4, so that the assigned maximum powers for the individual motor vehicles 1 can be adapted.This will be explained below using a greatly simplified example. It is assumed here that the subworker can provide 4 X kW of power (preferably with an additional safety margin). At present, three motor vehicles 1 are in the area of the first undercarriage 4, wherein the left motor vehicle 1 enters the area rather than the last motor vehicle 1 exits. If all motor vehicles 1 have the same priority, X / 4 power is initially transmitted to each motor vehicle 1 as maximum power. Thus, by driving in the first motor vehicle 1, there are also no power adaptations at all. After a while, the power requirement of the second motor vehicle 2 falls, so that the associated maximum power is no longer required, which is communicated to the lower structure 4. This non-called power can then be assigned by the sub-unit 4 to the remaining motor vehicles 1. The last motor vehicle 1 in the first sub-unit 4 then gradually approaches the end of the first sub-unit 4, wherein the central station 10 has communicated to the first sub-unit 4 that a power reserve is present in the second subsequent sub-unit 4, since currently only one motor vehicle 1 is located in the second sub-unit. The first sub-unit 4 then reduces the maximum power of the last motor vehicle 1, since its losses are the greatest because of the distance from the feed point and can subsequently be fully supplied again in the second sub-unit 4. However, it is also possible to assign a lower maximum power to the motor vehicles 1 independently of the supply position in the second sub-unit 4, if these power are removed from the feed point, wherein the reduction takes place, for example, in a plurality of stages as a function of the distance.Furthermore, increased priorities can be assigned to individual motor vehicles 1, so that increased maximum powers can be assigned to them compared to other motor vehicles 1. In addition to special vehicles, a traffic flow control can also be taken into account in order, for example, to supply vehicle platoons with a lead vehicle in an optimized manner.List of reference characters1 Motor vehicle 2 Current collector 3 Overhead line 4 Lower structure 5 Supply system 6 Mains connection 7 Inverter 8 Insulator 9 Communication interface 10 Central station 11 Communication interface 12 Control device 13 Converter 14 Electric motor 15 Battery

Claims

Method for the electrical energy supply of motor vehicles (1) by means of a supply system (5), wherein the supply system (5) has at least one undercarriage (4) with associated overhead lines (3) and the motor vehicles (1) have current collectors (2) for contacting the overhead lines (3), characterized in that the motor vehicles (1) communicate their future or current presence to the undercarriage (4) in the region of the undercarriage (4), wherein the undercarriage (4) or a superordinate control centre (10) determines in each case a maximum power for the individual motor vehicles (1), which the respective motor vehicle (1) is allowed to draw or feed to the undercarriage (4), wherein the determined maximum power is communicated to the respective motor vehicle (1) by the undercarriage (4) or the control centre (10), and the motor vehicles (1) additionally transmit further information to the undercarriage (4) or the control centre (10), wherein a priority is determined from the further information, which is taken into account in the power assignment, wherein a higher priority is assigned via bonus points to a motor vehicle (1) which had previously dispensed with an assigned power extraction within the scope of a payment or reward system.Method for the electrical energy supply of motor vehicles (1) by means of a supply system (5), wherein the supply system (5) has at least one undercarriage (4) with associated overhead lines (3) and the motor vehicles (1) have current collectors (2) for contacting the overhead lines (3), characterized in that the motor vehicles (1) communicate their future or current presence to the undercarriage (4) in the region of the undercarriage (4), wherein the undercarriage (4) or a superordinate control centre (10) determines in each case a maximum power for the individual motor vehicles (1), which the respective motor vehicle (1) is allowed to draw or feed to the undercarriage (4), wherein the determined maximum power is communicated to the respective motor vehicle (1) by the undercarriage (4) or the control centre (10), and the motor vehicles (1) additionally transmit further information to the undercarriage (4) or the control centre (10), wherein a priority is determined from the further information, which is taken into account in the power assignment, wherein the further information contains a property of the motor vehicle (1) as a refrigerated vehicle, hazardous vehicle or emergency vehicle, and / or driving of the motor vehicle (1) in a platoon, wherein a higher priority is assigned to the motor vehicles of a platoon.Method according to Claim 1 or 2, characterized in that the assigned maximum power of the motor vehicles (1) is dynamically adapted.Method according to one of the preceding claims, characterized in that the motor vehicles (1) communicate their actually drawn power or output power to the undercarriage (4).Method according to one of the preceding claims, characterized in that the motor vehicles (1) detect the voltage position on the overhead lines (3) and communicate it to the undercarriage (4).Method according to one of the preceding claims, characterized in that the motor vehicles (1) additionally transmit a power demand to the undercarriage (4) or the control centre (10), wherein a priority which is taken into account in the power assignment is determined from the power demand.Method according to one of the preceding claims, characterized in that the supply system (5) has at least two sub-units (4), wherein the maximum power is allocated by the first sub-unit (4) as a function of a state in a subsequent second sub-unit (4).Motor vehicle (1) having current collectors (2) for contacting overhead lines (3) and a control device (12) for at least one converter (13), wherein the control device (12) is designed to control the energy flow through the converter (13), characterized in that the motor vehicle (1) has at least one communication interface (11) which is designed to communicate with a undercarriage (4) and / or a control center (10) of undercarriages (4) and in the process to transmit a future or current presence of the motor vehicle (1) in the region of the undercarriage (4) to the undercarriage (4) and additionally further information to the undercarriage (4) or the control center (10), wherein the further information indicates a property of the motor vehicle (1) as a refrigerated vehicle, hazardous material vehicle or rescue vehicle, and / or include driving of the motor vehicle (1) in a platoon, wherein the control device (12) is configured to actuate the converter (13) such that a maximum power transmitted by the undercarriage (4) or the central unit (10) is not exceeded.Supply system (5) having at least one undercarriage (4) and overhead lines (3), characterized in that the supply system (5) has at least one communication interface (9) which is designed in such a way as to receive information from motor vehicles (1), wherein the information assigns a future or current presence of the motor vehicle (1) in the region of the undercarriage (4), wherein the supply system (5) is designed in such a way as to determine maximum services for the motor vehicles (1) and to transmit them, and, within the scope of a payment or reward system, to assign a motor vehicle (1) which has previously dispensed with an assigned power extraction a higher priority via bonus points.Supply system (5) having at least one undercarriage (4) and overhead lines (3), characterized in that the supply system (5) has at least one communication interface (9) which is designed in such a way as to receive information from motor vehicles (1), wherein the information contains a future or current presence of the motor vehicle (1) in the region of the undercarriage (4) and further information contains a property of the motor vehicle (1) as a refrigerated vehicle, hazardous material vehicle or rescue vehicle, and / or a driving of the motor vehicle (1) in a platoon, wherein the supply system (5) is designed in such a way as to determine maximum powers for the motor vehicles (1) and to transmit them to them, and to determine a priority from the further information and to take these into account in the power assignment.

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