Charging station for charging electric vehicles

Abstract

Charging station (1) for charging electric vehicles, comprising - an input (2) for supplying the charging station (1) with an alternating voltage, - a switchable AC / DC converter (3) for converting the alternating voltage into a direct voltage with a first voltage level, - a DC / DC converter (4) for converting the DC voltage into an output DC voltage with a second voltage level, - a control unit (5) for controlling the AC / DC converter (3) and the DC / DC converter (4), - an output (8) for delivering an output current with the output DC voltage - a DC current measuring device (6) for measuring the output current, wherein the DC current measuring device (6) is capable of measuring alternating currents and direct currents.

Description

[0001] The present invention relates to a charging station for charging electric vehicles and a method for charging electric vehicles with a charging station.

[0002] To charge electric vehicles, alternating current (AC charging) or direct current (DC charging) is typically supplied to the electric vehicle from a charging station. With AC charging, an on-board charger within the electric vehicle generates direct current from the supplied alternating current. The resulting direct current can then be used to charge the vehicle battery. However, the on-board charger typically has strict limits regarding the maximum voltage it can accept. Furthermore, the on-board charger must be designed differently for different charging stations (e.g., single- or three-phase), which makes it expensive and heavy.

[0003] DC charging eliminates the need for an on-board charger, saving weight and costs on the vehicle side. The alternating current provided by the charging station can be used directly to charge the vehicle battery. In commercial use of charging stations, billing the end customer for the energy delivered is often inadequate. Fixed prices per charging session or billing based on charging time typically do not reflect the amount of energy delivered and are undesirable for both the end customer and the charging station operator.

[0004] Charging options for charging electric vehicles with direct current are known from the documents US 2015 0 280 466 A1 and DE 10 2010 043 516 A1. These charging options include devices for measuring charging currents. Document EP 2 673 862 B1 discloses a method for processing and paying for a charging process of an electric vehicle. The publication "Eichrecht bei Ladeinfrastruktur: Gemessener Gleichstrom" (Calibration Law for Charging Infrastructure: Measured Direct Current) by Schwarzer, CM, dated December 17, 2018, describes the necessity and idea of ​​measuring the direct current transmitted from a charging station to an electric vehicle for charging the electric vehicle with a direct current meter and billing the charging process based on the measured amount of electricity.

[0005] It is therefore an object of the present invention to provide a charging station which does not have the disadvantages of the prior art described above and enables correct billing of the energy supplied to the end customer.

[0006] This object is achieved by a charging station according to claim 1.

[0007] The charging station according to the invention enables DC charging of an electric vehicle and correct billing of the transmitted energy by measuring the output current.

[0008] Advantageous embodiments and further developments of the invention can be found in the dependent claims and the description with reference to the drawings.

[0009] According to a preferred embodiment of the invention, the DC current meter is calibrated. This enables a legally secure and trustworthy business relationship between the end customer and the charging station operator. It is conceivable that the DC current meter is protected against tampering. This can be achieved, for example, by sealing it.

[0010] According to a further preferred embodiment of the invention, the charging station comprises a billing unit for billing the output current, wherein the DC current measuring device is configured to transmit measurement data to the billing unit. This enables the billing unit to convert the delivered electricity quantity into a purchase price. It is conceivable that the billing unit is configured to calculate the purchase price by multiplying the delivered energy quantity by an electricity price and adding it to a basic fee. It is also conceivable that the electricity price is staggered according to the delivered energy quantity. It is also conceivable that the billing unit comprises a data interface through which the electricity price and / or the basic fee can be updated.

[0011] According to a further preferred embodiment of the invention, the billing unit has a display unit for displaying the delivered output current and / or the billing unit has a payment terminal for paying for the delivered output current. This advantageously makes it possible to directly see during the charging process how high the purchase price is for the part of the charging that has already been carried out. It is conceivable that the payment terminal has a cash dispenser for accepting cash and / or a card reader for reading debit, credit, or customer cards. However, it is also conceivable that the payment terminal has a device for contactless payment, for example with NFC. It is also conceivable that the billing unit is configured with a billing interface for transmitting the measurement data to an external device.

[0012] According to a further preferred embodiment of the invention, the DC current measuring device is configured to transmit measurement data to the control unit. This advantageously allows the amount of energy delivered to be limited to a preset amount. It is also conceivable that the output current can be set to a specific level. Furthermore, this makes it possible to monitor the charging process and detect malfunctions.

[0013] According to a further preferred embodiment of the invention, the charging station comprises a communication interface, wherein the communication interface is configured to operate the control unit, wherein the communication interface is configured to output data from the control unit, wherein the communication interface preferably comprises an operating terminal for operating and outputting data. This advantageously enables the control and / or adjustment of settings of the charging station.

[0014] According to a further preferred embodiment of the invention, the communication interface is configured to operate the control unit and output data via Ethernet and / or Bluetooth and / or WLAN and / or EEBus and / or NFC and / or a USB port. This advantageously enables simple operation of the communication interface.

[0015] A further object of the invention to achieve the object formulated at the outset is a method for charging an electric vehicle with a charging station according to one of the preceding claims, wherein the AC / DC converter and the DC / DC converter are controlled by the control unit, the AC voltage of an input current is converted by the AC / DC converter into the DC voltage with the first voltage level, wherein the DC voltage is converted by the DC / DC converter into the output DC voltage with the second voltage level, wherein the electric vehicle is charged with the output current with the output DC voltage at the output, wherein the output current is measured with the DC current measuring device.

[0016] The method according to the invention enables the DC charging of an electric vehicle and the correct billing of the transmitted energy by measuring the output current.

[0017] According to a further preferred embodiment of the invention, measurement data is transmitted from the DC current meter to the billing unit. This enables the billing unit to convert the delivered electricity quantity into a purchase price. It is conceivable that the billing unit calculates the purchase price by multiplying the delivered energy quantity by an electricity price and adding this price to a base fee. It is conceivable that the electricity price is tiered according to the delivered energy quantity. It is also conceivable that the electricity price and / or the base fee are updated.

[0018] According to a further preferred embodiment of the invention, measurement data is transmitted from the DC current meter to the control unit. This advantageously allows the amount of energy delivered to be limited to a preset amount. It is also conceivable that the output current can be set to a specific level. Furthermore, this makes it possible to monitor the charging process and detect malfunctions.

[0019] All previously disclosed details, features and advantages relate both to the charging station according to the invention and to the method according to the invention.

[0020] Further details, features, and advantages of the invention will become apparent from the drawings and the following description of preferred embodiments with reference to the drawings. The drawings merely illustrate exemplary embodiments of the invention, which do not limit the inventive concept.

[0021] Fig. 1 schematically illustrates a charging station according to an exemplary embodiment of the present invention.

[0022] In Fig. 1 schematically shows a charging station 1 according to an exemplary embodiment of the present invention. The charging station 1 has the input 2, through which the charging station is supplied with power from a power grid (not shown). For this purpose, an alternating voltage of 3 V to 400 V is applied to the input. The charging station 1 also has the AC / DC converter 3, which converts the alternating voltage into a direct voltage with a first voltage level. The AC / DC converter 3 is controlled by the control unit 5. The AC / DC converter 3 can be switched off, so that the charging station 1 can also be used for AC charging. Connected to the AC / DC converter 3 is the DC / DC converter 4, which converts the electrical voltage applied to it from the first voltage level to a second voltage level. The DC / DC converter 4 is also controlled by the control unit 5.At output 8, where the output current for charging the electric vehicle is delivered, the charging station 1 features a DC current meter 6. The DC current meter 6 is calibrated and measures the amount of energy delivered to the electric vehicle in the form of output current. In addition to its functionality as a pure DC current meter, the DC current meter 6 is also capable of measuring alternating currents. This is described in the . Fig.1 is indicated by a conductor loop connected to the DC current meter 6. The DC current meter 6 is connected to the control unit 5 and provides it with measurement data regarding the delivered output current. Based on the measurement data, the control unit 5 controls the AC / DC converter 3 and the DC / DC converter 4. The control unit 5 can be operated via the communication interface 9, which is also provided for outputting data, for example operating parameters of the charging station 1. For this purpose, control commands and data are transmitted between an external terminal and the communication interface 9 via Ethernet and / or Bluetooth and / or WLAN and / or EEBUS and / or NFC and / or USB. Furthermore, the control unit can be operated via the operating terminal 9'. The billing unit 10 is connected to the DC current meter 6. This bills the amount of output current delivered and determines a purchase price.The output power quantity and the amount to be paid for the charge are displayed on the display unit 11 of the billing unit 10. Payment is made via the payment terminal 12. Information about the delivered output power quantity and the determined purchase price can also be transmitted from the billing interface 10' to an external device via Ethernet and / or Bluetooth and / or WLAN and / or EEBUS and / or NFC and / or USB. List of reference symbols 1 charging station 2 entrance 3 AC / DC converters 4 DC / DC converters 5 Control unit 6 DC current meter 8 Exit 9 Communication interface 9' control terminal 10 billing unit 10' billing interface 11 Display unit 12 payment terminals

Claims

[1] Charging station (1) for charging electric vehicles, comprising - an input (2) for supplying the charging station (1) with an alternating voltage, - a switchable AC / DC converter (3) for converting the alternating voltage into a direct voltage with a first voltage level, - a DC / DC converter (4) for converting the DC voltage into a DC output voltage with a second voltage level, - a control unit (5) for controlling the AC / DC converter (3) and the DC / DC converter (4), - an output (8) for delivering an output current with the output DC voltage - a DC current measuring device (6) for measuring the output current, wherein the DC current measuring device (6) is capable of measuring alternating currents and direct currents. [2] Charging station (1) according to claim 1, wherein the DC current measuring device (6) is calibrated. [3] Charging station (1) according to one of the preceding claims, wherein the charging station (1) has a billing unit (10) for billing the output current, wherein the DC current measuring device (6) is configured to transmit measurement data to the billing unit (10). [4] Charging station (1) according to claim 3, wherein the billing unit (10) has a display unit (11) for displaying the delivered output current and / or wherein the billing unit (10) has a payment terminal (12) for paying for the delivered output current. [5] Charging station (1) according to one of the preceding claims, wherein the DC current measuring device (6) is configured to transmit measurement data to the control unit (5). Charging station (1) according to one of the preceding claims, wherein the charging station (1) has a communication interface (9), wherein the communication interface (9) is configured to operate the control unit (5), wherein the communication interface (9) is configured to output data from the control unit (5), wherein the communication interface (9) preferably has an operating terminal (9') for operating and outputting data. [7] Charging station (1) according to one of the preceding claims, wherein the communication interface (9) is configured to operate the control unit (5) and to output data by means of Ethernet and / or Bluetooth and / or WLAN and / or EEBus and / or NFC and / or a USB port. [8] Method for charging an electric vehicle with a charging station (1) according to one of the preceding claims, wherein the AC / DC converter (3) and the DC / DC converter (4) are controlled by the control unit (5), the AC voltage of an input current is converted by the AC / DC converter (3) into the DC voltage with the first voltage level, wherein the DC voltage is converted by the DC / DC converter (4) into the output DC voltage with the second voltage level, wherein the electric vehicle is charged with the output current with the output DC voltage at the output (8), wherein the output current is measured with the DC current measuring device (6). [9] Method according to claim 8, wherein measurement data are transmitted from the DC current measuring device (6) to the billing unit (10). [10] Method according to one of claims 8 or 9, wherein measurement data are transmitted from the DC current measuring device (6) to the control unit (5).

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