Method and circuit arrangement for unlocking a charging plug in an emergency designed for a charging station for charging an electric energy storage of an electric vehicle

1. A method for unlocking a charging plug in an emergency designed for a charging station for charging an electric energy storage of an electric vehicle, the charging station comprising a locking mechanism ( 24 ) which is activated by an electric-motor drive unit ( 18 ), the method comprising the steps of:

providing a power supply for the electric-motor drive unit ( 18 ) during normal operation and emergency operation by means of a step-up converter ( 12 ),

evaluating a physical quantity as an input signal ( 62 ) for identifying a condition for initiating emergency operation by means of an emergency unlocking controller ( 2 ),

transferring data between the emergency unlocking controller ( 2 ) and a superordinate locking controller ( 8 ),

controlling and monitoring the step-up converter ( 12 ) by means of the emergency unlocking controller ( 2 ),

controlling and monitoring the electric-motor drive unit ( 18 ) during normal operation and emergency operation by means of the emergency unlocking controller ( 2 ), the locking mechanism ( 24 ) being unlocked during emergency operation via the electric-motor drive unit ( 18 ).

2. The method according to claim 1 , wherein the input signal is evaluated by detecting a line voltage of a power supply system, which supplies the charging station with power, by means of a coupling circuit ( 60 ) and by testing the line voltage by means of the emergency unlocking controller ( 2 ), the locking mechanism ( 24 ) being unlocked and a switch-off signal for a contactor being generated for isolating the electric vehicle from the charging station if the detected line voltage deviates from a value prespecified in the superordinate locking controller ( 8 ) or in the emergency unlocking controller ( 2 ) as a condition for initiating the emergency operation.

3. The method according to claim 1 , further including transferring data between the emergency unlocking controller ( 2 ) and a power supply module ( 42 ) of the charging station.

4. The method according to claim 3 , wherein the emergency unlocking controller ( 2 ) controls and monitors the power supply module ( 42 ).

5. The method according to claim 1 , further including:

monitoring a temperature via a temperature-signal input ( 70 ); and

generating a switch-off signal for a contactor should a violation of a temperature threshold have been determined.

6. The method according to claim 1 , further including:

monitoring charging-station parameters via a monitoring-signal input ( 90 ); and

generating a switch-off signal for a contactor should the charging-station parameters signalize a faulty state of the charging station.

7. The method according to claim 1 , wherein the electric energy stored in a storage capacitor of the power-supply module ( 42 ) is used during emergency operation.

8. The method according to claim 1 , further including providing a self-sufficient supply voltage for the emergency unlocking controller ( 2 ) by means of a self-sufficient power supply ( 52 ) supplied with energy by an energy storage ( 50 ).

9. A circuit arrangement ( 1 ) for unlocking a charging plug in an emergency designed for a charging station for charging an electric energy storage of an electric vehicle, the charging station comprising:

a locking mechanism ( 24 ), which is activated via an electric-motor drive unit ( 18 ), the circuit arrangement ( 1 ) comprising an emergency unlocking controller ( 2 ) having a microcontroller ( 4 ) which is configured for executing the method steps according to claim 1 taking place in the emergency unlocking controller ( 2 ),

a step-up converter ( 12 ),

a first communication interface ( 6 ) for transferring data between the emergency unlocking controller ( 2 ) and a superordinate locking controller ( 8 ),

a second communication interface ( 20 ) for transferring data between the emergency unlocking controller ( 2 ) and the step-up converter ( 12 ), and

a third communication interface ( 16 ) for transferring data between the emergency unlocking controller ( 2 ) and the electric-motor drive unit ( 18 ).

10. The circuit arrangement according to claim 9 , further including a coupling circuit ( 60 ) for detecting a line voltage of a power supply system supplying the charging station with power.

11. The circuit arrangement according to claim 9 , wherein the emergency unlocking controller ( 2 ) further comprises a fourth communication interface ( 40 ) for transferring data between the emergency unlocking controller ( 2 ) and a power supply module ( 42 ) of the charging station.

12. The circuit arrangement according to claim 9 , wherein the emergency unlocking controller comprises a temperature-signal input ( 70 ) for temperature monitoring,

an emergency switch-off signal output ( 80 ) for the emergency switch-off of a circuit contactor ( 82 ) during an emergency unlocking, and

a monitoring-signal input ( 90 ) for monitoring charging-station parameters.

13. The circuit arrangement according to claim 9 , further including a self-sufficient power supply ( 52 ), which is supplied with power by an energy storage ( 50 ), for providing a self-sufficient supply voltage for the emergency unlocking controller ( 2 ).