WO2021105639A1

WO2021105639A1 - Electric charging station

Info

Publication number: WO2021105639A1
Application number: PCT/FR2020/052215
Authority: WO
Inventors: Andrés YARCE
Original assignee: Balyo
Priority date: 2019-11-29
Filing date: 2020-11-27
Publication date: 2021-06-03
Also published as: EP4065409A1; FR3103974A1; FR3103974B1

Abstract

The invention concerns an electric charging station comprising an energy source, a charging cable and a robotic arm for moving a connector complementary to the electrical socket of the electrical equipment, and a charge controller detecting the electrical continuity at the connection terminals at the pilot wire of the battery to be charged. The charge controller comprises a functional safety module comprising: - a first set of relay(s), at least one of the coils of which is supplied by an electric circuit comprising a power source, and two terminals capable of establishing electrical contact with the terminals connected by the pilot wire of the battery, the first set of relay(s) being open when the electric circuit between the output of the charger and the corresponding electric pole of the battery is closed - and a second set of relay(s) controlled by the controller of the motorised arm for operating the motor of the motorised arm in PWM mode.

Description

DESCRIPTION

TITLE: Electric charging station

Field of the invention

The present invention relates to the field of electrically conductive recharging equipment for mobile equipment such as autonomous vehicles, in particular autonomous handling vehicles powered by rechargeable batteries.

This equipment usually includes a charging cable attached to the charger on the charging station, terminated by a connector located at the end of the charging cable complementary to a connector located on the electric vehicle in order to allow recharging of the electric battery.

For high amperage recharges (typically more than 100 amperes), it is usual to provide a charge controller making it possible to guarantee maximum user safety during recharging. This charging controller, on the infrastructure side, conditions the start of charging to the following tests:

- Check that the load is properly connected to the system

- Check that the vehicle earth is properly connected to the installation's protection circuit

- possibly verification of the consistency of the powers between the cable, the vehicle and the recharging circuit - optionally determination of the maximum recharging power which will be allocated to the vehicle.

All of these checks and communication are carried out through a specific wire communication, called "pilot wire". To this end, the connection of the sockets and socket outlets on the infrastructure side is equipped with two additional wires / pins - called pilot wires.

More particularly, the invention relates to an equipment for charging batteries of electric vehicles comprising a robotic arm ensuring the automatic displacement of the charging connector and its positioning and its connection with the socket of the electric vehicle to be recharged.

State of the art

American patent US9266440 is known, for example, in the state of the art, describing a robotic charging station for charging a battery of an electric vehicle, the charging station comprising: a base plate, a riser coupled to the base and extending substantially transversely of the base plate, a robotic arm extending from the riser and supporting an end effector. The robotic arm is configured to move the connector in three degrees of movement. A target tracking camera integrated with the end effector is configured to periodically produce a captured image. A controller is configured to receive the captured image from the target tracking camera, identify a pattern on the electric vehicle from the received captured image, determine a spatial relationship between the end effector and an electrical receptacle disposed on the electric vehicle from at least one of a size, an inclination or a position of the pattern in the captured image.

Disadvantages of the prior art The solutions of the prior art are not completely satisfactory because they leave security flaws: risk of crushing of the hand interposed between the socket and the battery when moving the motorized arm, risk of operation in the absence of battery or bad connection, ...

Solution provided by the invention

In order to remedy these drawbacks, the invention relates in its most general sense to an electric charging station comprising an energy source, a charging cable and a robotic arm ensuring the displacement of a complementary connector of the electrical outlet of the device. electrical equipment, and a charge controller detecting electrical continuity at the terminals for connection to the pilot wire of the battery to be recharged, characterized in that said charge controller comprises an operating safety module comprising:

- a first set of relay (s), at least one of the coils of which is supplied by an electrical circuit comprising an electrical source, and two terminals capable of establishing electrical contact with the terminals connected by the pilot wire of the battery, said first set of relay (s) being open when the electrical circuit between the output of the charger and the corresponding electrical pole of the battery is closed

- And by a second set of relay (s) controlled by the motorized arm controller for controlling the motor of the motorized arm in PWM mode.

According to different variants, taken individually or in technically compatible combination,

- Said first set of relays comprises a first relay and a second relay, the two coils of said relays being connected in parallel. - the coil of at least one of the relay (s) of said first set of relay (s) is connected on the one hand to the secure ground corresponding to the safety line of a contact detection edge, and to elsewhere at the output of the controller controlling the extension of said motorized arm.

the power terminal of said first relay connected to the motor controlling the extension of said motorized arm, the normally closed terminal being connected to the motor power supply circuit, the normally open terminal being connected to the power terminal of said second relay

- The normally open terminal of said second relay is connected to the coil of one of the relays of said second set and to the normally open terminal of another relay of said second set.

- the power terminal of the third relay (43) is connected to the second connection of the motor, said third relay controlling the withdrawal of the motorized arm, its coil being connected between ground and the controller controlling the retraction of the arm a fourth relay controls the switching power supply, its coil being connected between ground and the power terminal of a fifth relay

- the power terminal of the fourth relay is connected to the normally open terminals of the second relay and the third relay

- The coil of a fifth relay is connected between a battery presence detection circuit and the output of the motorized arm retraction controller.

Detailed description of a non-limiting example of the invention

The present invention will be better understood on reading the detailed description of a non-limiting example of the invention which follows, with reference to the appended drawings where: [Fig.l] Figure 1 shows a top view of a charging station according to the invention

[Fig.2] Figure 2 shows a front view of a load plate according to the invention

[Fig.3] Figure 3 shows the simplified electrical diagram of the invention

[Fig.4] Figure 4 shows the electrical diagram of the control circuit of the invention

Hardware architecture

The recharging station described by way of example in the following is a robot-controlled loading system for an electric robot forklift, which makes it possible to charge robot forklifts autonomously.

The charging station comprises a docking station (1) containing the electrical and electronic circuits as well as a system for actuating a charging plate (2) supported by a retractable arm (3).

The electrical and electronic circuits include a control system, a sensor identification system, an electrical system and a communication system.

The docking station has in the example described a first power supply for the actuator motor of the retractable arm and a second independent power supply for the electrical and electronic circuits. It has five buttons o a button (4) for the circuit breaker, o a button (5) to turn on / off, o a button (6) for the emergency stop, o a button (7) to reset, o a button (8) to reach / to retract, o a button (9) key for manual / auto mode The docking station also includes a retro-reflex sensor and four safety edges comprising one or more sensors which deliver an electrical signal in the event of contact with an obstacle or a person .

The presence identification system comprises an optical sensor for detecting the vehicle to be recharged, and mechanical sensors, which collect information relating to contacts with an obstacle or a person.

The communication system includes network and wireless communication, for the transmission of signals with a server.

The control system consists of the electronic card controlling the movements of the robotic arm and the electrical card.

The actuation system is mainly composed of a load plate (2), a linear motor and its control system, the role of which is to act as a mobile load robot arm.

The load plate (2) is shown in Figure 2 front view. It comprises an electrical contact (10) of power corresponding to the electrical ground, and an electrical contact (11) of power corresponding to the positive pole +48 V.

It also includes two electrical contacts (12, 13) corresponding to the detection of the presence of the battery (in English "interlock") and two electrical contacts (14, 15) for the control of the plate (2) by a digital signal. The electrical power contacts (10, 11) are formed by copper masses, for example pairs of transverse bars to allow the passage of strong currents.

The electrical contacts (12 to 14) are copper plates for the passage of less current. They correspond to complementary contacts on the battery (21), which are connected by a short-circuit link (22) in the battery.

The electrical system comprises a charger (30) with a pair of electrical cables (31, 32) for the 48 V power current connecting the charger (30) to the charging station (1), a pair of conductors (33, 34 ) for digital service signals, and a pair of leads (35, 36) for checking for the presence of a battery.

It includes a main board (25) receiving the signals from the external sensors, from the battery presence detection line (35, 36) and the control signals delivered by the charger (1) on the line (33, 34) to control the motor (28) of the motorized arm (2) via a circuit (26) as well as the relays (27) controlling the power supply.

The docking station is plugged into a battery charger (30) (24V, 400A), the power outlet (220V or 110V depending on the country). The charging plate (3) is pressed against the charging plate (20) of the battery (21) under the action of the motorized arm (2).

Automatic mode

When the charging station operates in automatic mode, it allows two operations.

The first operation concerns the engagement of the charging socket on the vehicle to be recharged. The system receives the activation command from an external device. The system waits for the presence of the robot whose relative position is provided by the aforementioned detection sensor.

When the presence of the vehicle is detected, the arm (3) supporting the load plate (2) deploys (using the access command) until the battery lock is detected;

When the battery lock is detected, a final push is made to ensure that the force exerted on the electrical contacts is sufficient. When the contact force is reached, the charger interlock line is activated. Charging then begins automatically.

The second operation concerns the withdrawal.

The system receives the deactivation order. The system then deactivates the loader interlock line. Charging stops automatically. The system monitors the charger current and waits for the current to drop to 0 amps. The arm then retracts until the retraction stop is reached.

External control mode

According to a second operating mode, the charging station receives commands transmitted by external peripherals.

The two types of operation described with reference to automatic mode can be enabled or disabled by a configuration parameter transmitted by an external device.

This parameter can be transmitted by network communication. The system is then equipped with an Ethernet connection and the ModBus protocol for communication with the associated vehicle server.

MANUAL MODE

In manual mode, there are two possible operations: The first operation concerns the engagement of the charging socket on the vehicle to be recharged.

If the control button is activated, the arm will extend (using the reach control) until the button is released or the battery lock is detected or the reach stop is reached.

When battery lockout is detected, the “last push” is made to ensure that enough force is exerted on the electrical contacts (only if the reach button is still active).

When the contact force is reached, the charger interlock line is activated

Charging should start automatically

Withdrawal operation:

If the pull-out control button is activated, the system will deactivate the loader interlock line if it is active.

Charging should stop automatically

The system monitors the charger current and waits for the current to drop to 0 amps.

The arm will retract until the button is released or the retract stopper retracts if reached.

SECURITY: DEFAULT MANAGEMENT

- If the engage-to-take and remove-take commands are received at the same time, no operation is allowed.

- If the retract command is received while the scope is in progress, the scope should be stopped and the retract action performed

- If the reach command is received while the withdrawal is in progress, the withdrawal movement must continue until the final stop is reached, if the command reach is still active, the reach action can be performed.

- If the reach movement is executed and the reach stop is reached, the docking station must signal an error and initiate an automatic retraction procedure.

If actuation is requested and the current consumption of the actuator is too low, the system should report an error.

If actuation is requested and the current consumption of the actuator is too high (short circuit), the system should report an error.

- If an actuation is requested and the final stop is not reached before a TimeOut parameter, the system must signal an error. The list of error signals is as follows o Category 1: Automatic erase o Category 2: manual erase o Category 3: Power cycle required to erase the connection plate o Category 4: service intervention required.

The electronic circuit includes a computer controlling the following functions:

- In automatic mode, no range actuation is allowed if the retro-reflex sensor is not active

- If the reach stop sensor is active, all range actuations are prohibited

- If the retraction stop sensor is active, any retraction actuation is prohibited

- Using the current measurements, the system should be able to estimate the force produced by the arm: o If the current is too high and the battery lock is not active, an automatic 1 second withdrawal should be performed and the system then reports an error. o If battery interlock is active, this estimate should be used to ensure that there is sufficient contact force o Any actuator activation (Reach or Retract) should be done with a linear increase in current via the PWM control.

Power control

Operating safety is ensured by two sub-assembly of electromechanical relays shown in figure.

4.

In the example described, the first relay subassembly consists of two relays (41, 42), the coils of which are supplied in parallel. This first sub-assembly controls the secure extension of the motorized arm (2).

The second subassembly of relays consists in the example described of three relays (43 to 45).

The coils of the two relays (41, 42) of the first sub-assembly are supplied on the one hand by a secure ground controlled by the safety barrier (46). In the event of contact with this safety barrier (46), the power supply is interrupted.

They are supplied on the other hand by the output of the controller (47) delivering the signal in pulse width modulation PMW controlling the extension of the motorized arm (2).

One of the motor connections (28) controlling the extension of the arm is connected to the power terminal of the first relay (41).

The normally closed terminal of the first relay (41) is connected to the controller (46), and the normally open terminal of the first relay (41) is connected to the power terminal of the second relay (42). The normally closed terminal of the second relay (42) is left in the air.

The normally open terminal of the second relay (42) is at the switched power supply corresponding to the power terminal of the fourth relay (44) and the normally open terminal of the third relay (43).

The power terminal of the third relay (43) is connected to the second connection of the motor (28). This third relay (43) controls the withdrawal of the motorized arm (2). Its coil is connected between ground and the controller

(48) controlling the retraction of the arm (2).

The fourth relay (44) controls the switching of the power supply. The coil is connected between ground and the power terminal of the fifth relay (45). The power terminal of the fourth relay (44) is connected to the normally open terminals of the second relay (42) and the third relay (43).

The coil of the fifth relay (45) is connected between a battery presence detection circuit (49) and the output of the retraction controller (48) of the motorized arm (2). The power terminal of the fifth relay (45) is connected to the battery presence detection line, the normally closed terminal is in open circuit and the normally open terminal corresponds to a battery detection signal.

Claims

1 - Electrical charging station comprising an energy source, a charging cable and a robotic arm ensuring the movement of a complementary connector of the electrical outlet of the electrical equipment, and a charge controller detecting electrical continuity at the terminals for connection to the pilot wire of the battery to be recharged, characterized in that said charge controller comprises an operating safety module comprising:

- a first set of two relays, called the first relay (41) and second relay (42), of which at least one of the coils is supplied by an electrical circuit comprising an electrical source, and two terminals capable of establishing electrical contact with the terminals connected by the pilot wire of the battery, said first set of relay (s) being open when the electrical circuit between the output of the charger and the corresponding electrical pole of the battery is closed

- And by a second set of three relays, called third relay (43), fourth relay (44), fifth relay (45) controlled by the controller of the motorized arm for driving the motor of the motorized arm in PWM mode.

2 - Electric charging station according to claim 1 characterized in that said first set of relays comprises a first relay and a second relay, the two coils of said relays being connected in parallel.

3 - Electric charging station according to claim 1 characterized in that the coil of at least one of the relay (s) of said first set of relay (s) is connected on the one hand to the secure ground corresponding to the line of safety of a contact detection edge, and on the other hand at the output of the controller controlling the extension of said motorized arm. 4 - Electric charging station according to claims 2 and 3 characterized in that

the power terminal of said first relay is connected to the motor controlling the extension of said motorized arm, the normally closed terminal being connected to a first connection of the motor, the normally open terminal being connected to the power terminal of said second relay

- And in that the normally open terminal of said second relay is connected to the coil of one of the relays of said second set and to the normally open terminal of another relay of said second set.

5 - Electric charging station according to claims 3 and 4, characterized in that the power terminal of the third relay (43) being connected to a second connection of the motor (28), said third relay (43) controlling the withdrawal of the arm motorized (2), its coil being connected between the mass and the controller (48) controlling the retraction of the arm (2).

6 - Electric charging station according to claim 1 characterized in that a fourth relay (44) controls the switching of the power supply, its coil being connected between ground and the power terminal of a fifth relay (45).

7 - Electric charging station according to the preceding claim characterized in that the power terminal of the fourth relay (44) is connected to the normally open terminals of the second relay (42) and the third relay (43).

8 - Electric charging station according to claim 1 characterized in that the coil of a fifth relay (45) is connected between a circuit (49) for detecting the presence of the battery and the output of the controller (48) for retraction of the motorized arm (2).