Charging plugs, charging cables and charging methods for an electric vehicle

Abstract

Charging plug (10) for an electric vehicle, with the following features: - contact pins (L1, N, PE) for making a plug connection with a coupling (12) and - temperature sensors (NTC1, NTC2, NTC3) thermally coupled to the contact pins (L1, N, PE) for detecting a temperature profile between the charging plug (10) and the coupling (12), characterized by a protective conductor contact part (22) electrically connected to one of the contact pins (L1, N, PE), which carries a further temperature sensor (NTC1, NTC2, NTC3).

Description

[0001] The present invention relates to a charging plug for an electric vehicle according to the preamble of claim 1. The invention further relates to a charging cable with such a plug and a corresponding method for charging an electric vehicle. State of the art

[0002] In the field of electromobility, vehicles are generally known whose batteries can be charged via a public power grid. Globally, there are numerous suitable power grids, charging plugs, and cables, each meeting a wide range of quality standards and subject to aging. Furthermore, there are diverse requirements for using this infrastructure.

[0003] To prevent overloading infrastructure components during the charging process, it has been repeatedly proposed to equip charging plugs with temperature sensors so that the charging current can be reduced or switched off if necessary. Examples of this teaching include US 6,905,362 B2, US 8,729,856 B2, and US 8,573,994 B2.

[0004] Occasionally, attempts have been made to verify the correct seating of the charging plug in the socket or connector using a Hall sensor. Such approaches are known, for example, from US 8,573,994 B2 and DE 20 2008 009 929 U1. The latter patent discloses a charging connector for electric vehicles comprising a plug part, a socket part, and a Hall sensor that outputs a different voltage when the charging plug is connected than when it is disconnected. Disclosure of the invention

[0005] The invention relates to a charging plug and a charging method for an electric vehicle according to the independent claims.

[0006] One advantage of this solution is the ability to directly monitor the temperature profile between the charging socket or connector and the charging plug during the charging process. This allows for the early detection of potential overheating of the connection due to improper use of the charging cable, which can then be prevented by switching off the charging process or reducing the current.

[0007] Further advantageous embodiments of the invention are specified in the dependent claims. For example, a circuit board facing the charging socket can be provided for mounting the temperature sensors, and a Hall sensor supported by the circuit board can be used to check the connector connection. The electrical mains connection required for charging can thus be checked for basic compatibility of the two connector parts even before the actual charging process begins. Various elements are suitable as temperature sensors, also called thermistors, such as NTC elements or PTC elements.

[0008] In a preferred embodiment, thermally conductive contact surfaces on the circuit board, fully and directly connected to the contact pins, serve to couple the temperature sensors to the contact pins. The circuit board thus simultaneously functions as a mounting platform, connection point, wiring point, and contact point for the temperature and Hall sensors. Additional components for the protective circuitry of the charging plug can also be mounted on it.

[0009] According to another aspect of the invention, the charging plug is connected to a so-called in-cable control and protective device by means of electrical signal lines. This device can use the common signal lines to activate both the Hall sensor and the temperature sensors.

[0010] Additionally, a further temperature sensor, located away from the contact pins, may be provided to detect any environmental temperature influence on the charging plug. The proposed geometric arrangement, for example on a protective conductor contact part of the charging plug electrically connected to one of the contact pins, allows, in combination with the sensors directly on the power contact pins, the measurement and evaluation of the temperature from standby mode and environmental influences such as sunlight or ambient temperature to be carried out in comparison to the temperature profile during a charging process.

[0011] Finally, a predetermined electrical resistance of at least one of the signal lines for encoding a thermal behavior of the charging plug makes it possible to store and assign various plug and housing variants and their respective different thermal behaviors along with corresponding characteristic curves in the charging electronics, and to trigger derived power reductions or even shutdowns. Brief description of the drawings

[0012] An embodiment of the invention is shown in the drawings and is described in more detail below.

[0013] Fig. Figure 1 shows a charging plug provided on a charging cable according to the invention, with a view of its circuit board.

[0014] Fig. 2 is a longitudinal section of the charging plug of the Fig. 1 in conjunction with a suitable coupling or mains socket.

[0015] Fig. 3 is one of the Fig. 2. Corresponding longitudinal section highlighting the temperature sensors of the charging plug.

[0016] Fig. Figure 4 is a simplified circuit diagram of the charging plug. Fig. 3 including the charging cable and its in-cable control box.

[0017] Fig. Figure 5 shows an optimal characteristic curve of the thermistors or NTC resistors underlying the temperature sensors. Embodiments of the invention

[0018] Fig. Figure 1 illustrates the basic structure of a charging plug according to the invention. 10 based on its front view. Visible are the components for creating a plug connection with the corresponding coupling. 12 The provided contact pins L1, N, PE and the temperature sensors NTC1, NTC2, NTC3, which are thermally coupled to the contact pins L1, N, PE, serve a purpose in Fig. 1. In-cable control box ICCPD (not shown) for recording the temperature profile between the charging plug during the charging process. 10 and its in Fig. 1 coupling not shown.

[0019] The mounting platform for the temperature sensors NTC1, NTC2, NTC3 is the one visible to the viewer. Fig. 1 facing circuit board LP, which also contains a Hall sensor 14 to check the plug connection between charging plug 10 and clutch. Thermally conductive contact surfaces. 16 The contact pins L1, N, PE of the printed circuit board LP fully encompass and, through their direct connection with the contact pins L1, N, PE, ensure their thermal coupling to the temperature sensors NTC1, NTC2, NTC3.

[0020] Other components, not shown in the drawing, may be mounted on the circuit board (LP) to provide protective circuitry for the charging plug. 10 to realize.

[0021] The longitudinal section of the Fig. Figure 2 illustrates the relative arrangement of the Hall sensor. 14 the charging plug 10 to a corresponding magnet 24 under the opposite surface of the clutch 12 or mains socket, if the contact pins L1, N, PE of the charging plug 10 into the corresponding contact openings of the coupling 12 intervene. The alternative position of the temperature sensor NTC1 is now also visible; it is located away from the contact pins L1, N, PE inside the charging plug housing. 10 , on the other hand, on a protective conductor contact part connected to the corresponding PE contact pin 22 It can be arranged.

[0022] The presentation of Fig. In contrast, section 3 highlights the specific design of the temperature sensors NTC1, NTC2, NTC3, which are thermistors or NTC resistors made from a so-called NTC pellet, using the temperature sensor NTC3 as an example.26 including corresponding connecting flags 28 consists of components that are encased in a thermally conductive and electrically insulating housing made of glass, ceramic, or similar material and are positively connected via this housing to the corresponding contact pin L1, N, PE. From the combined view with Fig. This results in a particularly suitable characteristic curve (5). 30 , which represents the specific resistance R of each temperature sensor NTC1, NTC2, NTC3 as a function of the temperature T at the corresponding contact pin L1, N, PE.

[0023] The interaction of the charging plug 10 the Fig. 3 with the charging cable encompassing it, which is only shown schematically in the drawing 36 and its in-cable control box ICCPD ultimately results from Fig. 4. The in-cable control box ICCPD, which controls the charging process, is connected to this via a six-pin signal ring. 34 by means of suitable electrical signal lines18 with the charging plug 10 connected, which are equally used to activate the Hall sensor 14 and the temperature sensors NTC1, NTC2, NTC3. Two of these signal lines 18 Predefined electrical resistances R1, R2 are used to encode the thermal behavior of the charging plug. 10 on, whose values ​​are stored in the memory of a microcontroller 32 The in-cable control box ICCPD correlates, thus allowing a conclusion to be drawn about the thermal behavior of the charging plug. 10 allow. QUOTES INCLUDED IN THE DESCRIPTION

[0024] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0025] US 6905362 B2

[0003] US 8729856 B2

[0003] US 8573994 B2 [0003, 0004] DE 202008009929 U1

[0004]

Claims

[1] Charging plug ( 10 ) for an electric vehicle, characterized by the following features: – Contact pins (L1, N, PE) for making a plug connection with a coupling ( 12 ) and – Thermally coupled temperature sensors (NTC1, NTC2, NTC3) to the contact pins (L1, N, PE) for recording a temperature profile between the charging plug ( 10 ) and the clutch ( 12 ). [2] Charging plug ( 10 ) according to claim 1, characterized by the following features: – one of the clutch ( 12 ) facing circuit board (LP) for mounting the temperature sensors (NTC1, NTC2, NTC3) and – a Hall sensor mounted on the printed circuit board (PCB) 14 ) to check the plug connection. [3] Charging plug ( 10) according to claim 2, characterized by thermally conductive contact surfaces that are fully and directly connected to the contact pins (L1, N, PE) ( 16 ) on the printed circuit board (PCB) for coupling the temperature sensors (NTC1, NTC2, NTC3) to the contact pins (L1, N, PE). [4] Charging plug ( 10 ) according to claim 2 or 3, characterized by components also mounted on the printed circuit board (PCB) for protective circuitry of the charging plug ( 10 ). [5] Charging plug ( 10 ) according to one of claims 2 to 4, characterized by common electrical signal lines ( 18 ) to activate the Hall sensor ( 14 ) and the temperature sensors (NTC1, NTC2, NTC3) through an in-cable control box (ICCPD). [6] Charging plug ( 10) according to one of claims 1 to 5, characterized by a further temperature sensor (NTC1, NTC2, NTC3) separated from the contact pins (L1, N, PE) for detecting an environmental temperature influence on the charging plug ( 10 ). [7] Charging plug ( 10 ) according to one of claims 1 to 5, characterized by a protective conductor contact part electrically connected to one of the contact pins (L1, N, PE) 22 ), which carries another temperature sensor (NTC1, NTC2, NTC3). [8] Charging cable ( 36 ) for an electric vehicle, characterized by the following features: – a charging plug ( 10 ) according to claim 5 and – which are connected via the signal lines ( 18 ) electrically with the charging plug ( 10 ) connected in-cable control box (ICCPD) for controlling a procedure for charging the electric vehicle. [9] Charging cable ( 36 ) according to claim 8, characterized bythat at least one of the signal lines ( 18 ) a predetermined electrical resistance (R1, R2) to encode a thermal behavior of the charging plug ( 10 ) exhibits. [10] Method for charging an electric vehicle using a charging cable ( 36 ) according to claim 8, characterized by that the process is controlled by the in-cable control box (ICCPD) as follows: – the plug connection is made using the contact pins (L1, N, PE), – the Hall sensor ( 14 ) is via the signal lines ( 18 ) activated, – the connector is checked using the Hall sensor ( 14 ) checked, – the temperature sensors (NTC1, NTC2, NTC3) are connected via the signal lines ( 18 ) activated and – The temperature profile is recorded during charging using the temperature sensors (NTC1, NTC2, NTC3).

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