EP3638536A1

EP3638536A1 - Dc/dc-charging device and method

Info

Publication number: EP3638536A1
Application number: EP18743594.6A
Authority: EP
Inventors: Andelko SUKER
Original assignee: Centralschweizerische Kraftwerke AG
Current assignee: Centralschweizerische Kraftwerke AG
Priority date: 2017-08-07
Filing date: 2018-07-09
Publication date: 2020-04-22
Also published as: WO2019030585A1

Abstract

A 150 kW DC/DC charging device (3) for a simultaneous electrical charging of batteries (9, 9a) of two electric vehicles (11, 11a) comprises an input connector (2) for connecting the charging device (3) to a 600 V DC public transportation overhead line (1). Thereby, an electrical input (Pi) is provided from the overhead line (1) to the charging device (3). Output connectors (10, 10a) are used for connecting the charging device (3) to the to-be-charged batteries (9, 9a) for providing an electrical output (Po) from the charging device (3) to the electric vehicles (11, 11a) for the charging of the batteries (9, 9a) of the vehicles (11, 11a). Two DC/DC converters (5, 5a) of the charging device (3) convert an input voltage (Ui) of the electrical input (Pi) to suitable output voltages (Uo) of the electrical output (Po) independently for each vehicle (11, 11a). Charging parameters are concurrently exchanged with the electric vehicles (11, 11a) which enables adaptation of the charging procedures to the charging states of the batteries (9, 9a). The charging device (3) further comprises a control unit (6) which is structured for controlling a charging operation of the charging device (3) based on an electrical load (L) of the overhead line (1). This electrical load (L) is determined using a power sensor (4) and using information received from a traffic management system of the public transportation network.

Description

DC/DC-Charging Device and Method

Technical Field

The invention relates to a charging device and method for an electrical charging of a load, such as a battery of an electric vehicle, from a source, in particular a public transportation DC overhead line. Further aspects of the invention relate to a charging method, a use of such a charging device for charging a load using such a charging method as well as to a use of an overhead line for the charging of a load.

Background Art

DE 20 2014 006 651 Ul discloses an overhead line charging device for electric vehicles.

US 2015/0097423 Al discloses an electric power supply network linked to a transport system.

EP 3 064 394 Al discloses a method / charger for charging a load.

EP 2 693 598 Al discloses a system and method for controlling the charging of batteries from an electric rail system.

The prior art solutions have the disadvantage, however, that they are not tailored or suitable for a reliable operation with a DC public transportation overhead line as found in many cities around the globe. Thus, additional costly infrastructure needs to be established with these solutions. Disclosure of the Invention

The problem to be solved by the present invention is therefore to provide a device and method that at least in part overcomes these disadvantages.

This problem is solved by the device and methods of the independent claims.

Accordingly, as a first aspect of the invention, a charging device for an electrical charging of an (electrical) load (i.e., an electrical storage device) comprises an input connector for connecting the charging device to an overhead line, in particular a DC overhead line of a public transportation network as found in many cities around the globe. Thus, an electrical input from the overhead line can be provided to the charging device. The charging device further comprises an output connector for connecting the charging device to the to-be-charged load. Thus, an electrical output can be provided from the charging device to the load which enables the charging of the load. The charging device further comprises an electrical converter for converting an input voltage of the electrical input to an output voltage of the electrical output. This output voltage is suitable for charging the load. Thus, the correct output voltage can be used for efficiently and safely charging the load. As known to the skilled person, it is also possible to achieve this voltage conversion step in a multi-step process where the input voltage is, e.g., not directly converted to the output voltage but, e.g., only indirectly over an internal system voltage of the charging device. Furthermore, the charging device comprises a control unit which is structured for dynamically controlling an operation of the charging device based on an electrical load (e.g., due to available power restrictions) of the overhead line. Thus, the operation of the charging device, in particular a charging level or charging intensity of the to-be-charged load, can be adapted to the electrical load of the overhead line. This facilitates an overhead-line-load-adapted operation of the charging device (or in other words the charging process of the to-be-charged load) which helps to ensure an uninterrupted operation of the overhead line, e.g., for other purposes such as public transportation operation fed by the overhead line which might have a higher priority than the charging of the electrical load. Specifically, as an example, the charging of the electrical load only takes place when the electrical load of the overhead line is low enough to ensure uninterrupted operation of the public transportation network because, e.g. no public transportation vehicles are accelerating in the specific electrical section of the over- head line.

The overhead line is advantageously a DC overhead line, in particular for providing electrical power to a public transportation network, in particular comprising a trolley bus and/or a streetcar and/or a sub- way etc. This helps to save costs because no costly separate electrical infrastructure is required for the charging device but the already present infrastructure (i.e. the public transportation overhead line) can be used which is already available and readily accessible in many cities and areas around the globe.

The overhead line advantageously has a nominal voltage, particularly DC voltage, between 400 V and 1100 V, in particular between 600 V and 750 V. This corresponds to the input voltage of the charging device.

Thus, the charging device can be more easily used for operation with already commonly used overhead line systems which operate in these voltage regimes.

The to-be-charged load advantageously comprises at least one rechargeable battery, in particular for an electric vehicle, in particular an electric car and/or bus and/or truck and/or an e-bike. Thus, the charging device helps to make these more environmentally friendly transportation means more commonly available.

In another advantageous embodiment, the load comprises an electrical, electrochemical, hydroelectric, thermal, and/or electromechanical storage device, in particular a capacitor and/or an inertia wheel and/or a hybrid device for electrical accumulation, in particular a home storage device and/or a district storage device. Thus, energy can be stored at home or in a district sub- station which can, e.g. be used for bridging a power failure in the electricity network and in general for contributing to a "smart grid" electricity approach.

Thus, uninterrupted service is facilitated.

In yet another advantageous embodiment, the charging device comprises a load sensor for determining the electrical load of the overhead line. This is advantageously achieved by a load signal indicative of the electrical load of the overhead line which is provided by the load sensor to the control unit of the charging de- vice, e.g. via an internal system bus as known to the skilled person. Different communication protocols as known to the skilled person can be used. Thus, the load of the overhead line can be more easily determined and used by the control unit for controlling the operation of the charging device, in particular an overhead-line-load- dependent charging level to the electrical load.

This load sensor advantageously comprises a voltage sensor and/or a power sensor. The load signal is then indicative of the input voltage and/or an input power of the electrical input from the overhead line to the charging device, respectively. This leads to an easier determination of the electrical load of the overhead line. In particular, the voltage sensor and/or the power sensor is/are arranged at the overhead line and/or at the charging device, particularly in direct contact with con- ductors connected to the overhead line. Thus, the electrical load of the overhead line can easier and more directly be determined.

In another advantageous embodiment, the charging device is structured to receive a load signal indicative of the electrical load of the overhead line from an external device, in particular from a traffic management system, e.g. monitoring the traffic situation of the public transportation network fed by the overhead line. Other options include an electrical network control system, and/or a grid control system. Further sensors, e.g. a voltage sensor and/or a power sensor can be foreseen which monitor the electrical properties of the overhead line and provide information indicative of the electrical load of the overhead line to this external device (e.g. the traffic management system) from where it is then transmitted to the charging device, e.g. via a secure connection over the internet or via a wireless data connection. Thus, various information sources can be used for determining the load of the overhead line which makes a load determination or prediction more reliable.

The control unit of the charging device is advantageously structured to control the converter of the charging device by means of a converter signal and based on the electrical load of the overhead line, e.g. via an internal system bus as known to the skilled person. Different communication protocols as known to the skilled person can be used. Thus, the operation control of the charging device is facilitated.

In an advantageous embodiment, the charging device is structured to stop and/or reduce and/or pause and/or cancel the charging of the to-be-charged load when the electrical load of the overhead line is (or increases) above a first predetermined threshold, e.g. when a public transportation vehicle such as a streetcar accelerates in the specific electrical section of the overhead line and draws electrical power from the overhead line thus increasing its electrical load (or lowering its voltage) . This facilitates an overhead-line-load-adapted operation of the charging device which helps to ensure an uninterrupted operation of the overhead line, e.g., for other purposes such as public transportation operation which might have a higher priority than the charging of the electrical load. The first predetermined threshold can of course also be changed during operation based on, e.g. traffic predictions or other parameters.

In yet another advantageous embodiment, the charging device is structured to begin and/or increase and/or unpause and/or resume the charging of the load when the electrical load of the overhead line is (or decreases) below a second predetermined threshold, e.g.

when a public transportation vehicle such as a streetcar decelerates in the specific electrical section of the overhead line and optionally provides electrical power to the overhead line thus decreasing its electrical load. This facilitates an overhead-line-load-adapted operation of the charging device which helps to ensure an uninterrupted operation of the overhead line, e.g., for other purposes such as public transportation operation which might have a higher priority than the charging of the electrical load. The second predetermined threshold can of course also be changed during operation based on, e.g. traffic predictions or other parameters.

Advantageously, the input connector is arranged at a mast of the overhead line. This helps to save costs because less costly separate electrical infrastructure is required for the charging device but the already present infrastructure (i.e. the public transportation DC overhead line) can be used which is already available in many cities and areas around the globe.

The charging device advantageously comprises a buffer device, e.g., comprising a capacitor and/or a rechargeable battery and/or a (regenerative) fuel cell. This helps to bridge periods of time when no or not enough electrical power can be drawn from the overhead line, e.g., due to a high electrical load of the overhead line. Thus, an uninterrupted charging by means of the charging device is facilitated.

In another advantageous embodiment, the charging device is structured for compensating for electrical load fluctuations of the overhead line on its electrical input. This is advantageously achieved using the buffer device of the charging device as discussed above. In other words, when the electrical load of the overhead line increases above a threshold, power can be fed back from the charging device (e.g., from the buffer device and/or from the to-be-charged load connected to the charging device) into the overhead line to compensate for these fluctuations and stabilize overhead line voltage. This helps to ensure uninterrupted service of the overhead line, e.g. for providing power to the public transportation network. Thus, also the overhead line stability is positively affected from the connected charging device .

Advantageously, the converter of the charging device is a DC/DC converter. In particular, the charging device solely comprises one or more DC/DC converters for converting the input voltage of the electrical input to the output voltage of the electrical output. In other words, advantageously, the charging device does not comprise a DC/AC converter and/or high-load (i.e., used for processing the charging electrical power, not solely interface or communication circuitry) AC circuitry. This helps to keep the design simple and does not create lossy conversion overhead in the case of a DC overhead line and a DC load. The term high-load as used herein relates to electrical powers of 100 W or above.

In another advantageous embodiment, the charging device further comprises a human-machine interface, e.g. a keyboard or a touchscreen for receiving a human input, e.g. from a user and/or for displaying a device output, e.g. to a user. Thus, the charging device can be more efficiently controlled, e.g. for setting charging parameters or for billing.

The charging device advantageously further comprises a communication device, in particular a wireless communication device, for transmitting and/or receiving a signal, e.g. for controlling the charging device. As an advantageous example, charging parameters and/or a status, in particular a charging status, can be exchanged with a charging circuitry of the electric vehicle (i.e. the to-be-charged load) . As another example, a wireless connection to a user' s smartphone can be established by means of which the user can control the operation of the charging device (thus taking over the functionality of the human-machine interface) . Thus, the charging device can be more efficiently controlled and the risk of maloperation is decreased.

The communication device is advantageously structured for exchanging charging device related data with another charging device which is particularly connected to the same overhead line or the same electrical section of the same overhead line than the first charging device. Then, the charging device and in particular also the other charging device are advantageously structured for dynamically controlling an operation of the charging device and of the other charging device, respectively, based not only on the electrical load of the overhead line but also based on the exchanged charging device (and in particular also other charging device) related da- taset(s). In this way, a network oriented optimization of the operations of the charging device and of the other charging device can be more easily implemented which reduces the risk of disadvantageous overcontrol situation in which the overhead-line-load-based control of the charging device and of the other charging device interact disadvantageously with each other. In an advantageous embodiment, the charging device has an electrical power, e.g. charging power, of at least 50 k , in particular of at least 150 k . Thus, the electrical load can be charged more quickly which reduces required charging times and thereby standstill times of the electric vehicle.

In another advantageous embodiment, the charging device is structured for the simultaneous electrical charging of at least two loads, e.g. batteries of two electric vehicles. Then, advantageously, the charging device comprises at least two converters, e.g. DC/DC converters. Thus, the charging of the electrical loads can be more easily decoupled from one another which facilitates more efficient charging processes and saves charging times.

As another aspect of the invention, a method for an electrical charging of a load is provided, in particular by means of a charging device as described above. The method comprises steps of:

- Providing an electrical input from an overhead line to a charging device by means of an input connector. Thus, the charging device can be connected to the overhead line for electrical input.

- Providing an electrical output from the charging device to the load for the electrical charging of the load by means of an output connector. Thus, the charging device can be connected to the to-be-charged electrical load.

- Converting an input voltage of the electrical input to an output voltage of the electrical output by means of a converter. Thus, the correct output voltage can be provided to the to-be-charged load for efficiently and safely charging the load.

- Hereby, the charging of the load is dynamically controlled based on an electrical load of the overhead line. Thus, the charging, in particular a charging level or charging intensity of the load, can be adapted to the electrical load of the overhead line. This facilitates an overhead-line-load-adapted charging (or in other words the charging process of the to-be-charged load) which helps to ensure an uninterrupted operation of the overhead line, e.g., for other purposes such as public transportation operation fed by the overhead line which might have a higher priority than the charging of the electrical load. Specifically, as an example, the charging of the electrical load only takes place when the electrical load of the overhead line is low enough to ensure uninterrupted operation of the public transportation network because, e.g. no public transportation vehicles are accelerating and draw a lot of power in the specific electrical section of the overhead line.

Advantageously, the electrical load of the overhead line is determined based on

* a measurement of the input voltage of the electrical input from the overhead line to the charging device and/or

* a measurement of an input power of the electrical input from the overhead line to the charging device and/or

* a received load signal indicative of the electrical load of the overhead line from an external device, in particular from a traffic management system, e.g. monitoring the traffic situation of the public transportation network fed by the electrical section of the overhead line.

Thus, various information sources can be used for determining the load of the overhead line which makes a load determination or prediction more reliable.

In an advantageous embodiment, the method comprises a further step of stopping and/or reducing and/or pausing and/or canceling the charging of the load when the electrical load of the overhead line is (or increases) above a first predetermined threshold, e.g. when a public transportation vehicle such as a streetcar accelerates in the specific electrical section of the overhead line and draws electrical power from the overhead line thus increasing its electrical load. This facilitates an overhead-line-load-adapted charging which helps to ensure an uninterrupted operation of the overhead line, e.g., for other purposes such as public transportation operation which might have a higher priority than the charging of the electrical load. The first predetermined threshold can of course also be changed during operation based on, e.g. traffic predictions or other parameters .

In another advantageous embodiment, the method comprises a further step of beginning and/or increasing and/or unpausing and/or resuming the charging of the load when the electrical load of the overhead line is (or decreases) below a second predetermined threshold, e.g. when a public transportation vehicle such as a streetcar decelerates in the specific electrical section of the overhead line and optionally provides electrical power to the overhead line thus decreasing its electrical load. This facilitates an overhead-line-load-adapted charging which helps to ensure an uninterrupted operation of the overhead line, e.g., for other purposes such as public transportation operation which might have a higher priority than the charging of the electrical load. The second predetermined threshold can of course also be changed during operation based on, e.g. traffic predictions or other parameters.

Another aspect of the invention relates to a use of a charging device as described above for an electrical charging of a load using a method as described above. Thus, loads such as electric vehicles can be more efficiently charged which helps to make these more environmentally friendly transportation means more commonly available . Yet another aspect of the invention relates to a use of an overhead line, in particular a DC public transportation overhead line, providing an electrical in put for an electrical charging of a load, in particular by means of a charging device as described above and/or in particular using a method as described above. The charging is achieved through an electrical output and an input voltage of the electrical input (i.e., from the overhead line) is converted to an output voltage of the electrical output (for connecting to the to-be-charged load) . The charging of the load is furthermore dynamically controlled based on an electrical load of the over head line. Thus, the charging, in particular a charging level or charging intensity of the load, can be adapted to the electrical load of the overhead line. This facili tates an overhead-line-load-adapted charging (or in othe words the charging process of the load) which helps to ensure an uninterrupted operation of the overhead line, e.g., for other purposes such as public transportation operation fed by the overhead line which might have a higher priority than the charging of the electrical load Specifically, as an example, the charging of the electri cal load only takes place when the load of the overhead line is low enough to ensure uninterrupted operation of the public transportation network because, e.g. no vehicles are accelerating in the specific electrical section of the overhead line.

Brief Description of the Drawings

The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. This description makes reference to the annexed drawings, wherein: Fig. 1 shows a first embodiment of a charging device 3 according to the invention as well as an overhead line 1 and a to-be-charged load 9,

fig. 2 shows a second embodiment of a charging device 3 according to the invention as well as an overhead line 1 and two to-be-charged loads 9, 9a, and fig. 3 shows a measured electrical load L of an overhead line over time with a first threshold Lu and a second threshold LI.

Modes for Carrying Out the Invention

Fig. 1 shows a first embodiment of a 50 k charging device 3 according to the invention. The charging device 3 comprises an input connector 2 at a mast 13 by means of which it is connected to a DC public transportation overhead line 1 with a nominal voltage of 600 V. An electrical input Pi is therefore provided from the overhead line 1 to the charging device 3. The charging device 3 further comprises an output connector 10 by means of which it is connected to a to-be-charged load 9 (i.e., a rechargeable battery 9 for an electric vehicle 11, see also below with regard to fig. 2) . An electrical output Po is thus provided from the charging device 3 to the battery 9 for charging the battery 9. The charging device 3 further comprises a DC/DC converter 5 for converting an input voltage Ui of the electrical input Pi to an output voltage Uo of the electrical output Po for efficiently and safely charging the battery 9. It is noted here that the charging device 3 does not comprise a DC/AC converter or other high-load AC circuitry used for high power conversion which facilitates the design of the charging device 3.

According to the invention, a control unit 6 of the charging device 3 (i.e., a microcontroller pC with a memory and computer readable instructions stored thereon, not shown) is structured for controlling the charging operation of the charging device 3 based on an electrical load L of the overhead line 1.

For this, a load sensor 4 provides a load signal SI which is indicative of the electrical load L of the overhead line 1 to the control unit 6. In the described embodiment, the load sensor 4 is a power sensor which measures the rated power of the overhead line 1. As an alternative or additional approach, a voltage sensor could be foreseen which measures the voltage Ui of the electrical input Pi from the overhead line 1 and therefrom determines a load signal SI which is indicative of the electrical load L of the overhead line 1 (not shown) .

Based on this load signal SI, the control unit 6 controls the converter 5 of the charging device 3 by means of a converter signal Sc (and other related circuitry of the charging device 3) and thus ensures that operation of the public transportation network is not negatively affected by the charging of the battery 9.

Some additional specifics are provided below with regard to the description of fig. 3.

The charging device 3 further comprises a buffer device 12 which comprises a battery and a capacitor and which is used to i) bridge periods of time when no or not enough electrical power can be drawn from the overhead line 1 due to a high electrical load of the overhead line 1 and ii) compensate for electrical load fluctuations of the overhead line by feeding electrical power back to the overhead line 1 when required. Thus, i) uninterrupted charging of the battery 9 is facilitated and ii) reliable operation of the public transportation network is assisted by the charging device 3.

The charging device 3 further comprises a human-machine interface 8 for inputting parameters such as charging parameters and billing details by a human user and for outputting status messages of the charging device and other information. These parameters can also be set via a user's smartphone connected to the charging device 3 via a wireless connection (not shown) . Thus, the charg^¬ ing device 3 can be more easily operated. A wireless communication device 7 of the charging device 3 is used for exchanging charging-related information with the control electronics of the battery 9 (as shown by the two radio antenna symbols) . Thus, the battery can be more efficiently and safely charged. Fig 2. shows a second embodiment of a charging device 3 according to the invention which is very similar to the first embodiment as described above with regard to fig. 1. As a first difference, the charging device 3 according to the second embodiment has an overall electrical power of 150 kW which results in a faster charging operation. As a second difference, an additional load signal SI' is received by the communication device 7 from a traffic management system (not shown) of the public transportation network which is fed with electrical power from the overhead line 1. This enables a more reliable electrical load level determination and prediction based on the current traffic situation. As a third difference, the charging device 3 comprises two DC/DC- converters 5, 5a and two output connectors 10, 10a for simultaneously charging the batteries 9, 9a of two electric cars 11, 11a. Thus, waiting times are reduced.

Fig. 3 shows a measured electrical load L of an overhead line 1 as shown in figs. 1 and 2 over time with a first load threshold Lu and a second load threshold LI. The charging devices 3 as discussed above are structured such that the charging levels/intensities of the battery/batteries 9, 9a are reduced when the electrical load L of the overhead line 1 rises above the first load threshold Lu. This first threshold Lu is concurrently updated based on traffic predictions, buffer charging status and other parameters. A rise above the first threshold can happen when a streetcar heavily accelerates in the electrical section of the overhead line 1 (see load spikes in the graph) . When the electrical load increases further, the charging is completely paused after the buffer device 12 is emptied or even cancelled when the high-load scenario persists.

The charging levels/intensities of the battery/batteries 9, 9a are increased/resumed when the electrical load L of the overhead line 1 decreases below the second load threshold LI. This second threshold LI is also concurrently updated based on traffic predictions, buffer charging status and other parameters. Thus, a reliable operation of the public transportation network is not affected by the charging operation because power is only drawn from the overhead line 1 when the electrical load L admits this, e.g., for accelerated charging of the batteries 9, 9a or for (re) charging of the buffer device 12.

Description of a preferred embodiment

A 150 kW DC/DC charging device 3 for a simultaneous electrical charging of batteries 9, 9a of two electric vehicles 11, 11a comprises an input connector 2 for connecting the charging device 3 to a 600 V DC public transportation overhead line 1. Thereby, an electrical input Pi is provided from the overhead line 1 to the charging device 3. Output connectors 10, 10a are used for connecting the charging device 3 to the to-be-charged batteries 9, 9a for providing an electrical output Po from the charging device 3 to the electric vehicles 11, 11a for the charging of the batteries 9, 9a of the vehicles 11, 11a. Two DC/DC converters 5, 5a of the charging device 3 convert an input voltage Ui of the electrical input Pi to suitable output voltages Uo of the electrical output Po independently for each vehicle 11, 11a. Charg- ing parameters are concurrently exchanged with the electric vehicles 11, 11a which enables adaptation of the charging procedures to the charging states of the batteries 9, 9a. The charging device 3 further comprises a control unit 6 which is structured for controlling a charging operation of the charging device 3 based on an electrical load L of the overhead line 1. This electrical load L is determined using a power sensor 4 and using information received from a traffic management system of the public transportation network.

Note:

It is further to be noted that when more than one charging device 3 is connected to the same electrical section of the overhead line 1, the charging devices 3 communicate with each other by means of the communication device 7 such that no overhead-line-load-based-controlling artefacts occur which helps to implement a network oriented optimization of the operations of the charging devices .

While there are shown and described presently preferred embodiments of the invention, it is to be distinctly understood that the invention is not limited thereto but may be otherwise variously embodied and practiced within the scope of the following claims.

Claims

1. A charging device (3) for an electrical charging of a load (9), the charging device (3) comprising:

- an input connector (2) for connecting the charging device (3) to an overhead line (1) for providing an electrical input (Pi) from the overhead line (1) to the charging device (3) ,

- an output connector (10) for connecting the charging device (3) to the load (9) for providing an electrical output (Po) from the charging device (3) to the load (9) for the charging of the load (9),

- a converter (5) for converting an input voltage (Ui) of the electrical input (Pi) to an output voltage (Uo) of the electrical output (Po) ,

characterized in that the charging device (3) further comprises

- a control unit (6) structured for dynamically controlling an operation of the charging device (3) based on an electrical load (L) of the overhead line (1) .

2. The charging device (3) of claim 1 wherein the overhead line (1) is a DC overhead line, in particular for providing electrical power to a public transportation network, in particular comprising a trolley bus and/or a streetcar and/or a subway.

3. The charging device (3) of any one of the preceding claims wherein the overhead line (1) has a nominal voltage between 400 V and 1100 V, in particular between 600 V and 750 V.

4. The charging device (3) of any one of the preceding claims wherein the load (9) comprises at least one rechargeable battery (9), in particular for an electric vehicle (11), in particular an electric car and/or bus and/or truck and/or an e-bike.

5. The charging device (3) of any one of the preceding claims wherein the load (9) comprises an electrical, electrochemical, hydroelectric, thermal, and/or electromechanical storage device, in particular a capacitor and/or an inertia wheel and/or a hybrid device for electrical accumulation, in particular a home storage device and/or a district storage device.

6. The charging device (3) of any one of the preceding claims further comprising a load sensor (4) for determining the electrical load (L) of the overhead line (1) , wherein the load sensor (4) is structured to provide a load signal (SI) indicative of the electrical load (L) of the overhead line (1) to the control unit (6) .

7. The charging device (3) of claim 6 wherein the load sensor (4) comprises a voltage sensor and/or a power sensor and wherein the load signal (SI) is indicative of the input voltage (Ui) and/or an input power of the electrical input from the overhead line (1) to the charging device (3) , and in particular wherein the voltage sensor and/or the power sensor is/are arranged at the overhead line (1) and/or at the charging device (3) .

8. The charging device (3) of any one of the preceding claims structured to receive a load signal (SI) indicative of the electrical load (L) of the overhead line (1) from an external device, in particular from a traffic management system, an electrical network control system, and/or a grid control system.

9. The charging device (3) of any one of the preceding claims wherein the control unit (6) is structured to control the converter (5) of the charging device (3) by means of a converter signal (Sc) and based on the electrical load (L) of the overhead line (1) .

10. The charging device (3) of any one of the preceding claims structured to stop and/or reduce and/or pause and/or cancel the charging of the load (9) when the electrical load (L) of the overhead line (1) is above a first predetermined threshold.

11. The charging device (3) of any one of the preceding claims structured to begin and/or increase and/or unpause and/or resume the charging of the load (9) when the electrical load (L) of the overhead line (1) is below a second predetermined threshold.

12. The charging device (3) of any one of the preceding claims wherein the input connector (2) is arranged at a mast (13) of the overhead line (1) .

13. The charging device (3) of any one of the preceding claims further comprising a buffer device (12) .

14. The charging device (3) of any one of the preceding claims structured for compensating for electrical load fluctuations of the overhead line (1) on the electrical input (Pi), in particular using the buffer device (12) of claim 13.

15. The charging device (3) of any one of the preceding claims wherein the converter (5) is a DC/DC converter, and in particular wherein the charging device (3) solely comprises one or more DC/DC converters for converting the input voltage (Ui) of the electrical input (Pi) to the output voltage (Uo) of the electrical output (Po) .

16. The charging device (3) of any one of the preceding claims not comprising a DC/AC converter and/or not comprising high-load AC circuitry.

17. The charging device (3) of any one of the preceding claims further comprising a human-machine interface (8) for receiving a human input and/or for displaying a device output.

18. The charging device (3) of any one of the preceding claims further comprising a communication device (7) , in particular a wireless communication device, for transmitting and/or receiving a signal.

19. The charging device (3) of claim 18 wherein the communication device (7) is structured for exchanging charging device related data with another charging device (3) , in particular connected to the same overhead line (1), wherein the charging device (3) and in particular also the other charging device (3) are structured for dynamically controlling an operation of the charging device (3) and in particular also of the other charging device (3) , respectively, based on the electrical load (L) of the overhead line (1) and based on the exchanged charging device related data.

20. The charging device (3) of any one of the claims 18 or 19 wherein the communication device (7) is structured to be connectable to the load (9) for receiving a signal indicative of a status of the load (9), in particular of a charging status of the load (9) .

21. The charging device (3) of any one of the preceding claims having an electrical power of at least 50 k , in particular of at least 150 kW.

22. The charging device (3) of any one of the preceding claims structured for the electrical charging of at least two loads (9, 9a), and in particular wherein the charging device (3) comprises at least two converters (5, 5a).

23. A method for an electrical charging of a load (9), in particular by means of a charging device (3) of any one of the preceding claims, the method comprising steps of:

- providing an electrical input (Pi) from an overhead line (1) to a charging device (3) by means of an input connector (2) for connecting the charging device (3) to the overhead line (1) ,

- providing an electrical output (Po) from the charging device (3) to the load (9) for the electrical charging of the load (9) by means of an output connector (10) for connecting the charging device (3) to the load (9),

- converting an input voltage (Ui) of the electrical input (Pi) to an output voltage (Uo) of the electrical output (Po) by means of a converter (5),

characterized in that the method comprises a further step of:

- dynamically controlling the charging of the load (9) based on an electrical load (L) of the overhead line (1) .

24. The method of claim 23 comprising a further step of

- determining the electrical load (L) of the overhead line based on * a measurement of the input voltage (Ui) of the electrical input from the overhead line (1) to the charging device (3) and/or

* a measurement of an input power of the electrical input from the overhead line (1) to the charging device (3) and/or

* a receiving of a load signal (SI) indicative of the electrical load (L) of the overhead line (1) from an external device, in particular from a traffic management system.

25. The method of any one of the claim 23 to

24 comprising a further step of

- stopping and/or reducing and/or pausing and/or canceling the charging of the load (9) when the electrical load (L) of the overhead line (1) is above a first predetermined threshold.

26. The method of any one of the claims 23 to

25 comprising a further step of

- beginning and/or increasing and/or unpaus- ing and/or resuming the charging of the load (9) when the electrical load (L) of the overhead line (1) is below a second predetermined threshold.

27. A use of a charging device (3) of any one of the claims 1 to 22 for an electrical charging of a load (9) using a method of any one of the claims 23 to 26.

28. A use of an overhead line (1) providing an electrical input (Pi) for an electrical charging of a load (9) through an electrical output (Po), in particular by means of a charging device (3) of any one of the claims 1 to 22, in particular using a method of any one of the claims 23 to 26, wherein an input voltage (Ui) of the electrical input (Pi) is converted to an output voltage (Uo) of the electrical output (Po) , characterized in that the charging of the load (9) is dynamically controlled based on an electrical load (L) of the overhead line (1) .