DE102014206164A1 - Infrastructure-side plug for a charging cable for charging an electrically driven means of transportation - Google Patents

Abstract

An electrically drivable locomotion means (10), a charging cable and an infrastructure-side plug (1) for a charging cable for charging an electrically drivable means of locomotion (10) are proposed. The infrastructure-side connector (1) comprises: a proximity sensor (4), wherein the proximity sensor (4) is adapted to generate a control signal for reducing a charging power or a discharging power when approaching a hand (5) of a user.

Description

State of the art

The present invention relates to an infrastructure-side connector for transmitting power between an electrical infrastructure (e.g., a household power outlet) and an electrical load, which is particularly useful for a charging cable for charging an electrically powered vehicle. In particular, the present invention relates to a plug for reducing a contact erosion when breaking a connector under electrical load.

When charging electric vehicles, it is observed that so-called "contact erosion" can occur at some of the infrastructure-side outlets used. This is damage to the contact surface which occurs when disconnecting the connection "under load", that is, while conducting an electric charging current. By an arc while the surface is melted small area. The increased roughness and the resulting oxidation of the contact surface lead in the medium or long term to a higher contact resistance, whereby damage to the contact by arcs and other thermal effects are promoted even further. Furthermore, an increased contact resistance, due to the adjusting itself at the contact point high operating temperature, a potential danger in terms of inadmissible heating. This is particularly critical to evaluate, since at such a damaged outlet only after some time of operation, a thermal decomposition can occur (eg during the nighttime charging phase of the electric vehicle). This effect can also occur on regularly checked installations within the sphere of influence of the accident prevention regulations for electrical systems and equipment (BGV A3).

In the field of household plugs (e.g., CEE7 / 4 or CEE7 / 7 connectors), no solutions to prevent disconnection under load have heretofore been known. Among other things, this is due to the fact that most powerful devices, such as e.g. Washing machines, dryers, radiators, etc., fixed and usually rarely be plugged. The problem of separating under load is therefore not here.

In the commercial environment, on the other hand, there are known special systems for preventing unwanted disconnection under load, which include mechanical measures (e.g., levers, fittings or other interlocking measures). These actuators force a "manual release" in advance of the disconnection of the electrical connection.

Furthermore, special connectors are known, which ensure by their construction a required minimum opening speed. Due to the minimum opening speed, the duration of the arc and thus the contact erosion is low. For this purpose, a specific geometry with specific path / time sequence is required, which is realized for example by pressure points or pressure thresholds in the form of locking lugs and spring systems. Systems are also known which prevent the formation of an arc by integrating energy-dissipating electrical components or structures.

DE 10 2013 200 864 A1 discloses an adapter for electric vehicle charging systems that includes a switch referred to as a "proximity sensor" for closing or opening a pilot line of a vehicle. If it is detected via the proximity sensor that the adapter is arranged on a vehicle input socket, a charging process is enabled.

US 2013/0241479 A1 discloses a security system for charging stations for charging electrically powered vehicles. In order to interrupt the electrical energy supply or conversion in the event of a collision with the charging station, a proximity sensor for monitoring a presence of two corresponding units is provided. If the proximity sensor sends an extraordinary signal, the control circuit causes the charging process to stop.

Based on the aforementioned prior art, it is an object of the present invention to reduce contact erosion when disconnecting an electrical connection of an infrastructure-side plug of a charging cable from an infrastructure-side socket.

Disclosure of the invention

The above object is achieved by an infrastructure-side connector with the features of claim 1 and a charging cable with the features of claim 7 and an electrically driven means of locomotion with the features of claim 10. For this purpose, the infrastructure-side connector comprises a proximity sensor which is set up to generate a control signal for reducing a transmitted electrical power, a charging power or a discharging power when approaching a hand of a user. In other words, the proximity sensor is adapted to generate the control signal before opening the connector or issue. The proximity sensor is thus configured to generate the control signal whenever the user grips the infrastructure-side plug according to the invention for the purpose of unplugging the plug or approaches the plug for this purpose. In this way it is prevented that the user in the case of a charging cable, the infrastructure-side connector for releasing the connection can detect sufficiently firmly before the charging power or discharge capacity could be reduced according to the invention. An actuation of the infrastructure-side connector is possible in this way only under reduced charging power or discharge capacity. In this way, an undesirable and electrically disadvantageous contact erosion of the electrical plug contacts of the infrastructure-side plug due to arcing is effectively prevented.

The dependent claims show preferred developments of the invention.

The infrastructure-side plug can be configured compatible with standard household sockets. In many European countries such sockets are used in the range between 220 V and 240 V AC. Relevant standards for such connectors are CEE7 / 4 and CEE7 / 7. Depending on the country, such plugs are also referred to as "plug type F", "plug type E" or as "Schuko (for" protective contact ") - plug". In this way, a contact erosion is reduced or avoided according to the invention even when using household sockets.

Preferably, the plug may have an output for a control line. At least one port for such a control line may be included in the infrastructure-side connector. In this way, the charging power or discharge capacity can be exposed in a connected to the plug charger via a control signal. The other end of the control line can be connected, for example, in a control box (English "in cable control box" or "in cable control protection device" (ICCPD)) or within a control device arranged in a means of locomotion. In this way, the plug according to the invention can be kept compact, while remote power reduction units can provide the sometimes bulky components.

Alternatively or additionally, the infrastructure-side connector may also comprise first switching means which are set up to reduce the charging power or the discharging power or to end the charging / discharging operation in response to a signal from the proximity sensor. By this variant, the control line can be omitted, whereby the charging cable can be made more cost effective and compact.

The first switching means may preferably be set up to reverse the reduction of the charging power or the discharging power if the infrastructure-side plug is not actually disconnected from the infrastructure (socket) within a predefined period of time since the input of the control signal or since the control signal has been applied becomes. In this way, for example, by temporary approach of users, strangers, pets, etc., a charging process is not interrupted unnecessarily long.

Preferably, the proximity sensor is adapted to respond to a proximity of human tissue. More preferably, the proximity sensor is made immune to an approach of other materials. In this way it can be prevented that, for example, a cover of a socket, which rests during the charging process on the infrastructure-side plug according to the invention, does not cause the proximity sensor to output the control signal.

The proximity sensor may, for example, function capacitively and / or electrostatically and / or electroresistically. Such sensors are cost-effective and compact, so that their integration in the infrastructure-side plug according to the invention does not unnecessarily increase its volume and price.

According to a second aspect of the present invention, a charging cable for charging an electrically driven means of transport is proposed, which is closed on one side with an infrastructure-side connector according to the first-mentioned aspect of the invention. In addition, the charging cable has a vehicle-side plug, which, for example, as a type 2 connector (see IEC 62196 ) can be configured. The vehicle-side connector is used for a temporary connection of a vehicle-side socket. A power line between the infrastructure-side connector and the vehicle-side connector is used to transfer electrical energy for charging a traction battery of the means of transport. The features, feature combinations, and benefits resulting therefrom correspond to those embodied in connection with the infrastructure-side connector, so that reference is made to the above statements to avoid repetition.

The charging cable may further comprise a signal line between the infrastructure-side connector and the vehicle-side connector. The signal line is used to transmit the control signal. One end of the signal line is on the infrastructure side Plug, another end in a control box within the power line and / or disposed within the vehicle-mounted connector. Depending on the configuration, a unit arranged in the control box or in the means of locomotion can thus cause the charging power or the discharging power to be reduced in response to receipt of the control signal. For example, a second switching means can be controlled, by means of which the electrical connection between the infrastructure-side plug and the traction battery of the means of locomotion is interrupted. However, a low-wear electronic reduction of the charging power or the discharging power is preferably carried out by the charger used.

According to a third aspect of the present invention, there is provided an electrically powered vehicle which is connected via a power line to an infrastructure-side connector according to the first aspect of the present invention. Usually this is done, as in connection with the charging cable according to the invention, via a vehicle-side connector. However, solutions are sometimes preferred in which so-called automatic retractors (as known, for example, in household vacuum cleaners) stow the infrastructure-side plug and the power line. Even in such a case, an optional signal line between the infrastructure-side connector and the means of locomotion for the transmission of the control signal may be provided. Of course, in connection with all aspects and a wireless transmission of the control signal can be technically realized, including the infrastructure-side connector instead of the control line receives a corresponding wireless communication device.

The present invention is used for the safe electrical charging of electric vehicles at one example in the household of a customer existing electrical house installation ("home network"). In addition to a fault current cut-off (FI circuit), various monitoring functions (voltage monitoring, short-circuit monitoring, contactor monitoring, etc.) are integrated in the power electronics of such infrastructure facilities and the house installation thus basically suitable for charging an electrically driven vehicle. The invention proposes the integration of a proximity sensor into the infrastructure plug of the charging cable. In this case, commercially available proximity sensors can be used. The greatest benefit or the best possible sensitivity results from the use of a design of the sensor which is adapted to the particular design of the plug housing or the expected point of contact to be reached by the user. Technically suitable, for example, inductive, capacitive, galvanically coupled or electromagnetic sensors. As soon as an object enters the sphere of influence of the sensor, this causes, for example, the detuning or changing of the frequency of a respective system-specific oscillator, which in turn is detected by a detector stage. Depending on the evaluation parameters of the measuring signal, it can be assumed that a user's intention to disconnect exists. If this is the case, then the control causes an immediate reduction of the charging current. This can be done, for example, via the communication signal of a charging device (according to FIG IEC 61851 Pulse width modulation (PWM)) take place. Instead of having the charging current reduced by, for example, an electronic charger of the electric vehicle, it would also be possible to use a relay which is arranged, for example, in a control box and / or in the vehicle.

All devices referred to as "switching means" in the context of the present invention may be configured as low-wear electronic devices (e.g., including a phase control and / or a frequency conversion) to reduce or interrupt energy transfer.

Brief description of the drawings

Hereinafter, embodiments of the invention will be described in detail with reference to the accompanying drawings. In the drawings:

1 a representation of components for carrying out a charging process according to the invention;

2 a detailed view of an embodiment of an infrastructure-side plug according to the invention; and

3 an embodiment of an inventively designed vehicle.

Embodiments of the invention

1 shows a household standard Schuko socket 6 as an infrastructure-side socket, which for charging an electrically driven car 10 to be used as a means of transportation. A charging cable 2 has this an infrastructure-side connector, for example in the form of a Schuko plug 1 on. The Schuko plug 1 has an exit 7 for a power line 3 and a control line 8th on. The control line 8th ends in a control box 12 by which the charging process can be secured and parameters of the electrical energy can be converted. A switch 13 is as second switching means in the control box 12 provided to respond in response to a signal from a (in 1 not shown) proximity sensor 4 to reduce the charging power. The vehicle side is the charging cable according to the invention 2 through a type 2 plug 11 completed. This serves the temporary connection with the electrically driven car 10 ,

2 shows the approach of a hand 5 a user to an embodiment of a Schuko plug according to the invention 1 , A proximity sensor 4 detects the proximity of the hand 5 and recognizes therein the desire of the user to interrupt the infrastructure-side plug connection of the charging cable. An evaluation unit in the form of a microcontroller 15 is set up, the signals of the proximity sensor 4 and in response to reaching a predefined threshold for the signal over a control line 8th one inside the Schuko plug 1 arranged switch 9 to open as the first switching means. Subsequently, the microcontroller recognizes 15 also falling below a predefined threshold value for the signal of the proximity sensor 4 , In response, the microcontroller starts 15 a timer, after which expires without re-recognition of an approach of the switch 9 closed again and the charging process is resumed. Alternatively, the evaluation unit can also be used in the in 1 shown control box 12 or be arranged in a connected consumer.

3 shows a car 10 , which via a control line 8th and a power line 3 permanently with a grounded plug according to the invention 1 connected is. Also this safety plug 1 has a proximity sensor 4 and a microcontroller connected to it 15 as evaluation unit. The from the microcontroller 15 output control signals are via a control line 8th into the car 10 where she runs a charger 14 induce a power supply to a traction battery 16 reduce electronically.

Although the aspects and advantageous embodiments of the invention have been described in detail with reference to the embodiments explained in connection with the accompanying drawings, modifications and combinations of features of the illustrated embodiments are possible for the skilled person, without departing from the scope of the present invention, the scope of protection the appended claims are defined.

LIST OF REFERENCE NUMBERS

1

Safety plug

2

charge cable

3

power line

4

Proximity sensor

5

Hand of the user

6

Infrastructure-side Schuko socket

7

Output for control line and power line

8th

control line

9

switch

10

car

11

Type 2 connector

12

control box

13

switch

14

charger

15

microcontroller

16

traction battery

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102013200864 A1 [0006]
• US 2013/0241479 A1 [0007]

Cited non-patent literature

• IEC 62196 [0017]
• IEC 61851 [0020]

Claims (10)

Infrastructure-side plug for a charging cable ( 2 ) for charging an electrically driven means of transportation ( 10 ) comprising: - a proximity sensor ( 4 ), whereby the proximity sensor ( 4 ), when approaching a hand ( 5 ) a user a control signal for reducing a means of the infrastructure-side connector ( 1 ) to generate transmitted electrical power, in particular a charging power or a discharge power. Infrastructure-side connector according to claim 1, wherein the plug ( 1 ) compatible with standard household sockets ( 6 ), in particular according to the standard CEE7 / 4 and / or CEE7 / 7, is configured. Infrastructure-side connector according to claim 1 or 2, wherein the plug ( 1 ) an output ( 7 ) for a control line ( 8th ) configured to transmit a control signal for reducing a charging power and a discharging power, respectively. Infrastructure-side connector according to one of the preceding claims, further comprising first switching means ( 9 ) arranged to reduce the charging power and the discharging power in response to the control signal. Infrastructure-side connector according to claim 4, wherein the first switching means ( 9 ) are set up to reverse the reduction of the charging power or the discharging power if the infrastructure-side plug ( 1 ) not within a predefined time since a request for the control signal from the infrastructure ( 6 ) is separated. Infrastructure-side connector according to one of the preceding claims, wherein the proximity sensor ( 4 ) is adapted to respond to a proximity of human tissue, and in particular is set up - capacitive, and / or - to work electrostatically, and / or - electro-resistive. Charging cable comprising an - infrastructural connector ( 1 ) according to one of the preceding claims, - a vehicle-side connector ( 11 ), and - a power line ( 3 ) between the infrastructure-side connector ( 1 ) and the vehicle-side connector ( 11 ). Charging cable according to claim 7, further comprising a signal line ( 8th ) for transmitting the control signal between the infrastructure-side connector ( 1 ) and the vehicle-side connector ( 11 ). Charging cable according to one of claims 7 or 8 further comprising - a control box ( 12 ) between the infrastructure-side connector ( 1 ) and the vehicle-side connector ( 11 ), whereby the control box ( 12 ) second switching means ( 13 ) for reducing the charging power or the discharging power. Electrically drivable means of locomotion comprising one via a power line ( 3 ) with the means of transportation ( 10 ) connected infrastructure-side plug ( 1 ) according to one of claims 1 to 5, and in particular a signal line ( 8th ) for transmitting the control signal between the infrastructure-side connector ( 1 ) and the means of transportation ( 10 ).

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