Road vehicle with current collector

Abstract

The invention relates to an electrically or hybrid-driven road vehicle (10), in particular a truck, comprising a current collector (12) for transmitting electrical power by contacting a contact line (21) of an electrical overhead line installation (20) that guides an electrical contact line voltage (U). In this case, power input from the overhead line system (20) takes place in the traction mode, and power feedback into the overhead line system (20) takes place in the recovery mode. According to the invention, the road vehicle (10) comprises a measuring device (13) for detecting a currently applied contact line voltage (U) and a control device (14) connected to the measuring device for switching on and off a power transmission. The control device (14) is designed to close the power input when a lower threshold value (U1) of the contact line voltage (U) falls below and to close the power input again after the end of a randomly selected switch-on delay when the lower threshold value (U1) is exceeded. By means of such a road vehicle (10), it is possible to avoid traffic situations in the power supply section of the overhead line installation (20) that are overloaded.

Description

[0001] The invention relates to an electrically or hybrid-electrically driven road vehicle according to the preamble of claim 1.

[0002] Such a road vehicle, in particular a truck or a bus, comprises an electric or hybrid electric traction drive. It also comprises a current collector for transmitting electric power via a contact wire of an overhead line facility. The overhead line facility installed on the line side can be designed as a two-pole, i.e., having two contact wires designed as a go and return conductor, which are parallel to each other and extend above the carriageway of the electrified line section. The line-side substation provides the electrical contact wire voltage to the supply section (Speiseabschnitte) of the overhead line facility. In traction operation, power is fed from the overhead line facility into the road vehicle in order to provide energy for the traction drive and, if necessary, to charge the energy storage device on the vehicle side. In regenerative operation, power feedback can also be carried out from the road vehicle to the overhead line facility in order to output excess energy via the contact wire to the supply section being driven.

[0003] The contact line voltage provided by the substation fluctuates at its rated value depending on the operation of the vehicles in the power supply section. The contact line voltage decreases as the number of road vehicles traveling in the power supply section increases during traction operation. In particular, power supply sections with a high number of vehicles traveling on rising road courses or traffic jams pose a challenge to overhead line facility operators in terms of load-dependent energy management. Various central methods are known from the prior art to solve this problem.

[0004] International publication WO2013 / 064447A2 discloses a system for traffic control of electric vehicles, which can be coupled to a contact wire network arranged on the road side to transmit energy during driving. The contact wire network has supply sections with configurable load limits that are supplied separately from each other. Through a prediction device, the load demand in the supply section is determined by the detected traffic and weather conditions and the road gradient according to a prediction model, which indicates its load pressure according to the total weight of the vehicle, its speed and acceleration under different road gradients and weather conditions. The predicted load demand is evaluated in terms of the load limit of the supply section so as to select the required control intervention for the influencing device in the form of a vehicle device arranged in the vehicle when necessary. The vehicle device can issue an instruction to reduce the load pressure to the vehicle driver as a control intervention. In terms of the supply section with a risk of overload, the control device selects between a predetermined avoidance route, a speed limit, a prohibition of entry, a driving guide for eliminating traffic jams, and a request for switching from electric drive to fuel drive, for converting the load pressure from the contact wire network to a vehicle-side energy storage device, or for feeding back energy from the vehicle-side energy storage device to the contact wire network.

[0005] European Publication EP3756931A1 is known as an energy supply system for non-track electric drive vehicles on a road section of a road network. It includes an overhead line facility with a contact line extending above the lane of the road section and a substation for supplying electric energy to the contact line. Here, the contact line can be contacted by the collector of the vehicle to consume power. The overhead line facility is designed with a load limit for the electric power output on the road section. It also includes a communication system for wirelessly transmitting driving instructions for limiting electric power consumption to vehicles traveling on the road section. The communication system has a line-side communication unit and a vehicle-side communication unit. The line-side communication unit can be designed as an RFID tag with a storage unit for driving instructions, wherein the vehicle-side communication unit is designed as an RFID reader, which is arranged to wirelessly read the stored driving instructions when passing through the line-side communication unit. The line-side communication unit can also be designed to actively transmit driving instructions through a dedicated short-range communication according to the IEEE802.11p protocol (WLAN) or a mobile wireless network according to the C-V2X or 5G standard. The energy supply system further comprises a central controller configured to generate driving instructions for the road segment and transmit the instructions via the communication system. The control center is configured to dynamically generate the driving instructions based on current power demand on the road segment, current operating data of the substation, current or predicted traffic density on the road segment, vehicle categories of vehicles traveling on the road segment, current weather data on the road segment and / or current temperature of the contact wire.

[0006] The known systems are very complex in terms of the information and central and vehicle-side devices required to generate the driver instructions which reduce power consumption and transmit them from the central unit to the vehicle devices.

[0007] The object of the present invention is therefore to provide a road vehicle of the type mentioned above, with which traffic situations with a risk of overload in the power supply section can be avoided.

[0008] This object is achieved by a road vehicle having the features indicated in the characterizing part of the claims.

[0009] The invention is therefore based on an electric or hybrid-electrically driven road vehicle, in particular a heavy commercial vehicle, comprising a collector for the transmission of electrical power through a contact line of a conducting electrical contact line voltage of an electrical overhead line facility. Here, power is input from the overhead line facility in traction operation and power is fed back into the overhead line facility in recovery operation. According to the invention, the road vehicle also comprises a measuring device for detecting the currently applied contact line voltage and a control device connected to the measuring device for switching on and off the power transmission. The control device is designed to shut down the power input when it is below a lower threshold value of the contact line voltage and to switch on the power input again after the randomly selected switch-on delay has expired when the lower threshold value is exceeded. If the measuring device determines that the contact line voltage drops to a value below the lower threshold value, the control device switches off the power transmission to the road vehicle to prevent an overload situation in the power supply section being driven. The contact line voltage can thus be increased again so that the power input can be switched on again from the point of exceeding the lower threshold value. In order to avoid overload situations due to almost simultaneous switching on of the power transmission of all road vehicles traveling in the supply section, a switch-on delay is randomly selected in each control unit and the power input is not switched on again until the switch-on delay has expired. Due to the random selection of the switch-on delays, the switch-on times are also randomly distributed among the road vehicles in contact with the contact wire. As a result, the power consumption of these road vehicles is evened out, which can avoid overloads in the supply section. For this purpose, only vehicle-side devices are required and no communication with the control center of the overhead line system is required.

[0010] In an advantageous embodiment of the road vehicle according to the invention, the control device is designed to randomly select a first time period from a predeterminable first time window as a switch-on delay and to switch the power supply on again if the first time period has expired since the lower threshold value of the contact line voltage was exceeded. A time window is predetermined for the switch-on delay, within which a first time period is randomly selected, for example by a random generator. After the expiration of a first time period selected specifically for each road vehicle, the power supply of the road vehicle travelling in the supply segment is switched on again. By means of the random distribution of the first time periods, the power consumption received again is smoothed, so that undesirable load peaks can be avoided. The time window can be fixedly parameterized or can be predetermined according to a typical traffic density or a typical load consumption for the supply segment. The greater the load demand in the supply segment, the larger the time window is selected so that the switching on of the power supply in the road vehicle can be distributed.

[0011] In another advantageous embodiment of the road vehicle according to the invention, the control device is designed to randomly select a first voltage value from a predeterminable first voltage range as a switch-on delay and to switch the power input on again if the contact line voltage, which has risen again since exceeding a lower threshold value, reaches the first voltage value. A first voltage range is predetermined for the switch-on delay, within which the first voltage value is randomly selected, for example by a random generator. After reaching a first voltage value selected specifically for each road vehicle, the power input of the road vehicle traveling in the power supply section is switched on again. By means of the random distribution of the first voltage values, the re-accepted power consumption is moderated, so that undesirable load peaks can be avoided. The first voltage range can be fixedly parameterized or can be predetermined according to a typical traffic density or a typical load consumption for the power supply section. The greater the load demand in the power supply section, the larger the first voltage range is selected, so that the switching on of the power input in the road vehicle can be distributed.

[0012] In a further advantageous embodiment of the road vehicle according to the invention, the control device is designed to switch off the power input after a randomly selected switch-off delay has expired when the contact line voltage falls below a lower threshold value. In this way, when the contact line voltage falls below the lower threshold value due to an overload, the load consumption in the supply section can not be throttled suddenly for all road vehicles at the same time, but rather separately by means of switch-off delays which, as described above, can be realized by means of randomly generated points in time or voltage values.

[0013] In another advantageous embodiment of the road vehicle according to the invention, the control device is designed to turn off the power feedback when the upper threshold value of the contact wire voltage is exceeded, and to turn on the power feedback again after the randomly selected connection delay ends when the upper threshold value is exceeded. If the measuring device determines that the contact wire voltage rises to a value above the upper threshold value, the control device turns off the power transmission from the road vehicle to prevent the contact wire voltage from rising further in the power supply section being traveled. The contact wire voltage can thus fall again so that the power feedback can be turned on again from the point where it falls below the upper threshold value. In order to avoid almost simultaneous connection of the power transmission of all road vehicles traveling in the power supply section, a connection delay is randomly selected in each control unit, and the power feedback is only turned on again after the connection delay ends. Due to the random selection of the connection delay, the connection time points are also randomly distributed between the road vehicles in contact with the contact wire. The power output by these road vehicles is thus homogenized, so that a rapid rise in the contact wire voltage in the power supply section can be avoided. For this purpose, only vehicle-side devices are required, and communication with the control center of the overhead line facility is not required.

[0014] In another advantageous embodiment of the road vehicle according to the invention, the control device is designed to randomly select a second time period from a predeterminable second time window as the switch-on delay and to switch the power feedback on again if the second time period has expired since the upper threshold value of the contact line voltage was undershot. A second time window is predetermined for the switch-on delay, within which the second time period is randomly selected, for example by a random generator. After the expiration of the second time period selected specifically for each road vehicle, the power feedback of the road vehicles travelling in the power supply section is switched on again. By means of the random distribution of the second time periods, the re-received power output is moderated, so that undesirable voltage peaks can be avoided. The second time window can be fixedly parameterized or can be predetermined according to a typical traffic density or a typical load output for the power supply section. The greater the load output in the power supply section, the larger the second time window is selected so that the switching on of the power feedback in the road vehicles can be distributed.

[0015] In another advantageous embodiment of the road vehicle according to the invention, the control device is designed to randomly select a second voltage value from a predeterminable second voltage range as a switch-on delay and to switch the power feedback on again if the contact line voltage, which has dropped again from below an upper threshold value, reaches the second voltage value. A second voltage range is predetermined for the switch-on delay, within which second voltage values ​​are randomly selected, for example by a random generator. After reaching a second voltage value selected specifically for each road vehicle, the power feedback of the road vehicle traveling in the power supply section is switched on again. By means of the random distribution of the second voltage values, the re-received power output is moderated, so that undesirable voltage peaks in the contact line can be avoided. The second voltage range can be fixedly parameterized or can be predetermined according to a typical traffic density or a typical load output for the power supply section. The greater the load output in the power supply section, the larger the second voltage range is selected, so that the switching on of the power feedback in the road vehicle can be distributed.

[0016] In a further advantageous embodiment of the road vehicle according to the invention, the control device is designed to switch off the power feedback after a randomly selected switch-off delay has expired when an upper threshold value of the contact line voltage is exceeded. In this way, when the contact line voltage rises above the upper threshold value due to an overload, the load output in the supply section can not be increased suddenly for all road vehicles at the same time, but rather separately by switch-off delays, which, as described above, can be realized by randomly generated points in time or voltage values.

[0017] Further features and advantages of the present invention are apparent from the following description of exemplary embodiments with reference to the accompanying drawings, in which:

[0018] Figure 1 An embodiment of a road vehicle according to the invention is shown,

[0019] Figure 2 Show Figure 1 Voltage-power diagram for road vehicles.

[0020] according to Figure 1 According to the invention, a road vehicle 10 with an electric or hybrid electric traction drive 11, such as a heavy commercial vehicle, is supplied with electrical energy from an electrical overhead line facility 20 installed on the line side on a section S of a road network. For example, the right lane L of a multi-lane highway can be electrified in that two contact wires 21 designed as outgoing and return conductors are parallel to each other and suspended above the lane height along the lane L. In the power supply section of the overhead line facility 20, a substation 22 provides a contact line voltage U applied to the contact wire 21. In order to transmit electrical power P, the road vehicle 10 has a collector 12, which can include, for example, a pantograph-shaped support and two contact rockers with friction strips supported thereon. During driving, the friction strips of the collector 12 are in electrical friction contact with the corresponding contact wires 21 of the overhead line facility 20. The overhead line facility 11 is designed to have a load limitation for the transmission of electrical power on the section S. The contact line voltage U varies depending on the number of road vehicles 10 connected to the overhead line installation 20 in the supply section, in particular the number of road vehicles 10 travelling in traction mode and in recovery mode and the vehicle-specific power transmission of each individual road vehicle 10 .

[0021] Therefore, according to Figure 2 Electrical power P can only be transmitted between the road vehicle 10 and the overhead line installation 20 within a range of values ​​[U1; U2] of the contact line voltage U predetermined by the design of the overhead line installation 20. Power input below a lower threshold value U1 of the contact line voltage U is not possible in the traction operation of the road vehicle 10; likewise power feedback above an upper threshold value U2 of the contact line voltage U is not possible in the regenerative operation of the road vehicle 10. The maximum power Pmax is transmitted within a range of values ​​[U3; U4] of the contact line voltage U, which lies within the range of values ​​[U1; U2] defined by the lower threshold value U1 and the upper threshold value U2. In the traction operation of the road vehicle 10, the power input is throttled at the contact line voltage U3 and switched off at the lower threshold value U1. In the regenerative operation of the road vehicle, the power feedback is throttled at the contact line voltage U4 and switched off at the upper threshold value U2. To this end, the road vehicle 10 comprises a measuring device 13 for detecting the currently applied contact wire voltage U and a control device 14 connected to the measuring device for switching the power transmission on and off, the control device being designed to switch off the power input when the contact wire voltage falls below a lower threshold value U1 and when the contact wire voltage U exceeds an upper threshold value U2.

[0022] According to the invention, the control device 14 is designed to switch the power input, which was switched off after falling below a lower threshold value U1 of the contact line voltage U, back on after a randomly selected switch-on delay has expired when the lower threshold value U1 has been exceeded. The control device 14 can be designed to randomly select a first time period from a predeterminable first time window as the switch-on delay, and to switch the power input on again if the first time period has expired since the lower threshold value U1 of the contact line voltage U was exceeded. However, the control device can also be designed to randomly select a first voltage value from a predeterminable first voltage range as the switch-on delay, and to switch the power input on again if the contact line voltage U, which has risen again since the lower threshold value U1 has been exceeded, has reached the first voltage value.

[0023] In this way, an overload situation caused by almost simultaneous switching on of the power supply of all road vehicles 10 traveling in the power supply section is avoided by the vehicle itself randomly selecting a switch-on delay in each control unit 14 and switching on the power supply again only after the switch-on delay has expired. Due to the random selection of the switch-on delay, the switch-on times are also randomly distributed among the road vehicles 10 in contact with the contact wire 21. As a result, the power consumption by these road vehicles 10 is evened out, so that overloads in the power supply section can be avoided.

[0024] The first time period or the first voltage value is randomly selected within a first time window or a first voltage range, for example by a random generator, which can be fixedly parameterized or can be predetermined according to a typical traffic density or a typical load consumption for the power supply section. The greater the load demand in the power supply section, the larger the first time window or the first voltage range is selected, so that the switching on of the power input in the road vehicles 10 can be distributed.

[0025] The control device 14 can also be designed to switch off the power input after a randomly selected switch-off delay has expired when the contact line voltage U falls below a lower threshold value U1. In this way, when the contact line voltage U falls below the lower threshold value U1 due to an overload, the load consumption in the power supply section can not be throttled suddenly for all road vehicles at the same time, but rather separately by means of switch-off delays, which, as described above, can be realized by means of randomly generated time points or voltage values.

[0026] In addition, the control device 14 can be designed to shut down the power feedback when the upper threshold value U2 of the contact wire voltage U is exceeded, and to turn on the power feedback again after the randomly selected switch-on delay has expired when the upper threshold value U2 has been exceeded. If the measuring device 13 determines that the contact wire voltage U has risen to a value above the upper threshold value U2, the control device 14 shuts down the power transmission from the road vehicle 10 to prevent the contact wire voltage U from rising further in the power supply section being traveled. The contact wire voltage U can thus drop again so that the power feedback can be turned on again after falling below the upper threshold value U2. In order to avoid almost simultaneous switching on of the power transmission of all road vehicles 10 traveling in the power supply section, a switch-on delay is randomly selected in each control device 14, and the power feedback is only turned on again after the switch-on delay has expired. Due to the random selection of the switch-on delay, the switch-on time points are also randomly distributed between the road vehicles 10 in contact with the contact wire 21. As a result, the power output by these road vehicles 10 is homogenized, thereby preventing a rapid rise in the contact wire voltage U in the power supply section.

[0027] Analogously to the traction operation, the control device 14 can be designed for the regeneration operation to randomly select a second time period from a predeterminable second time window or a second voltage value from a second voltage range as a switch-on delay and to switch the power feedback on again if the second time period has ended since falling below the upper threshold value U2 of the contact line voltage U or the contact line voltage U has reached the second voltage value. The second time period or the second voltage value can be randomly selected within the second time window or the second voltage range, for example by a random generator, which can be fixedly parameterized or can be predetermined according to a typical traffic density or a typical load consumption for the power supply section. The greater the load output in the power supply section, the larger the second time window or the second voltage range is selected, so that the switching on of the power feedback in the road vehicle 10 can be distributed.

[0028] The control device 14 can also be designed to switch off the power feedback after a randomly selected switch-off delay has expired when the upper threshold value U1 of the contact line voltage U is exceeded. In this way, when the contact line voltage U rises above the upper threshold value U2 due to an overload, the load output in the power supply section can not be increased suddenly for all road vehicles 10 at the same time, but can be increased separately by the switch-off delay, which can be realized by a randomly generated time point or voltage value as described above.

Claims

1. An electrically or hybrid-electrically driven road vehicle (10), in particular a truck, comprising a current collector (12) for transmitting electrical power via a contact line (21) for conducting an electrical contact line voltage (U) of an electrical overhead line installation (20), wherein: In traction operation, power is input from the overhead line facility (20), and in recovery operation, power is fed back into the overhead line facility (20). The invention is characterized in that a measuring device (13) for detecting the currently applied contact line voltage (U) and a control device (14) connected to the measuring device for switching on and off the power transmission are provided, wherein the control device is designed to switch off the power input when the contact line voltage (U) falls below a lower threshold value (U1), and to switch on the power input again after a randomly selected switch-on delay has expired when the lower threshold value (U1) is exceeded.

2. The road vehicle (10) according to claim 1, wherein: The control device (14) is designed to randomly select a first time period from a predeterminable first time window as a switch-on delay and to switch the power input on again if the first time period has elapsed since a lower threshold value (U1) of the contact line voltage (U) was exceeded.

3. The road vehicle (10) according to claim 1, wherein: The control device (14) is designed to randomly select a first voltage value from a predeterminable first voltage range as a switch-on delay and to switch the power input on again if the contact line voltage (U) which has risen again since exceeding a lower threshold value (U1) reaches the first voltage value.

4. The road vehicle (10) according to claim 1, wherein: The control device (14) is designed to switch off the power input after a randomly selected switch-off delay has expired when the contact line voltage (U) falls below a lower threshold value (U1).

5. The road vehicle (10) according to claim 1, wherein: The control device (14) is designed to switch off the power feedback when an upper threshold value (U2) of the contact line voltage (U) is exceeded and to switch the power feedback on again after a randomly selected switch-on delay has expired when the upper threshold value (U2) is fallen below.

6. A road vehicle (10) according to claim 5, wherein: The control device (14) is designed to randomly select a second time period from a predeterminable second time window as a switch-on delay and to switch the power feedback on again if the second time period has elapsed since the contact line voltage (U) fell below an upper threshold value (U2).

7. A road vehicle (10) according to claim 5, wherein: The control device (14) is designed to randomly select a second voltage value from a predeterminable second voltage range as a switch-on delay and to switch the power feedback on again if the contact line voltage (U), which has dropped again from below an upper threshold value (U2), reaches the second voltage value.

8. The road vehicle (10) according to any one of claims 5 to 7, wherein: The control device (14) is designed to switch off the power feedback after a randomly selected switch-off delay has expired when an upper threshold value (U2) of the contact line voltage (U) is exceeded.

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