JP2013048523A - Vehicle charging system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent such a situation that an auxiliary battery runs out in an inserted state of a plug after the full charge from a charging station in a vehicle charging system.SOLUTION: A charge control circuit 104 detects, in a charger 103 the state that a plug 401 is connected with a connector 106 after the end of charging to a battery for running 102. Next, whenever a prescribed monitoring time passes, the charge control circuit 104 submits the charge instruction at a prescribed charging time to the auxiliary battery 101 to charging station 200 in the connection state of plug 401 through communication circuits 105 and 202. As a result, the power supply of a prescribed charging time is performed from the charging station 200 to the charger 103 and the charger 103 is made to perform additional charging to the auxiliary battery 101.

Description

  The present invention relates to a technique for preventing a battery from rising in a vehicle charging system.

  In recent years, plug-in hybrid vehicles and EV vehicles (electric vehicles: electric vehicles) have been rapidly developed (hereinafter referred to as “EV vehicles etc.” or simply “vehicles”), charging stations for charging vehicles and home charging. Widespread use of chargers and other charging stations. In a vehicle charging system for controlling charging from a charging station, a system in which a charger for controlling charging of a battery in the vehicle from the charging station is mounted on the vehicle as an in-vehicle charger is common. .

  As the battery in the vehicle, there are a traveling battery for driving a traveling motor and an auxiliary battery for driving an electronic / electrical circuit in the vehicle. For this reason, the vehicle-mounted charger supplied with electric power from the charging station needs to control charging to both the traveling battery and the auxiliary battery.

  The on-vehicle charger functions while the vehicle is stopped, and can be activated when a charging plug is inserted from the outside. For this reason, the in-vehicle charger needs to be always in a standby state (sleeping state as a processor unit for controlling the in-vehicle charger) even when the vehicle is stopped, and it is an issue to suppress current consumption during the stop. Yes.

  Such a problem is not limited to the on-vehicle charger, and in an EV car or the like, various devices have been made to suppress current consumption. In particular, it has been found that in an in-vehicle charger, current consumption increases when the plug is not removed after the end of charging, compared to a state where a charging plug is not inserted (normal stopping state). This is because a charging signal called a control pilot signal (CPLT signal) is always sent from the charging system side in the plug insertion state, so that the on-vehicle charger cannot enter a complete sleep state until the plug is unplugged. That is why. If the in-vehicle charger cannot be put into a complete sleep state, power is supplied from the auxiliary battery to the in-vehicle charger.

  For this reason, in EV cars, etc., there is a situation in which the auxiliary battery rises only by leaving the vehicle in the plug-insertion state for a while even though the user performs charging from the charging station. Can do. Since the traveling battery is not used unless the vehicle travels, the traveling battery does not rise when the vehicle is left with the plug inserted.

  As a conventional technique for preventing the auxiliary battery from rising, a technique is known in which the auxiliary battery is charged from the traveling battery at regular intervals after the ignition switch is turned off (for example, Patent Document 1). . It is conceivable to apply this prior art in a state where the plug is inserted from the charging station. However, in this conventional technique, in a case where the plug is inserted after being fully charged from the charging station, charging is stopped even though the charging station is connected and the power is used effectively. However, the power of the battery for traveling is consumed.

  The following techniques are known as other conventional techniques for preventing the auxiliary battery from rising. When the charging start timing set by the user is after a predetermined time has elapsed, the power supply from the internal power supply circuit to the CPU or the like is stopped until the power supply from the charging station to the electric vehicle is started, and the power supply is started. Then, it is the technique which restarts electric power supply (for example, patent document 2). Here, a control pilot signal is always sent from the charging station to the vehicle side to notify the connection of the charging station even after charging from the charging station to the running battery in the vehicle is completed and the charging is stopped. Continue to be. Therefore, since the on-vehicle charger or the control circuit for controlling the vehicle-mounted charger must continue to receive the control pilot signal, the on-board charger cannot enter a complete sleep state. However, there is a problem that the electric power is consumed.

  The following techniques are known as other conventional techniques for preventing the auxiliary battery from rising. While the sub power storage device is being charged, the system main relay of the main power storage device is kept on and the voltage conversion operation by the AC / DC converter is continued. As a result, the operation of the auxiliary machine (including the ECU) is continued during the charging period of the sub power storage device, and the auxiliary battery is prevented from rising. However, with this technology, there is a possibility that the circuit configuration for controlling the power supply connection between the main power storage device and the sub power storage device becomes complicated, resulting in an increase in cost. Also, in cases such as when the plug is inserted after full charging from the charging station, charging is stopped even though the charging station is connected, and the power cannot be used effectively. There has been a problem that the power of the power storage device (traveling battery) is consumed.

JP 2006-174619 A JP 2010-288317 A JP 2010-124535 A

  An object of the present invention is to prevent a situation in which an auxiliary battery rises in a plug insertion state after full charging from a charging station.

  According to the present invention, a power supply cable plug connected to a charging station is connected to a vehicle connector to supply power from a power supply cable to a charger for charging a running battery and an auxiliary battery in the vehicle, and a charging stand. In a vehicle charging system that communicates charging control information related to a charging operation with a vehicle, a plug connection state detection unit that detects a state in which the plug is connected to the connector after charging of the traveling battery, and a plug In the connected state, every time a predetermined monitoring time elapses, the charging station is instructed to charge the auxiliary battery for a predetermined charging time, whereby the charging station supplies power to the charger for the predetermined charging time. And an additional charging unit for charging the auxiliary battery.

  According to the present invention, a predetermined time is added from the charging station to the auxiliary battery in the vehicle 0 every time a certain period of time elapses while the plug of the power cable is inserted into the connector after the charging of the traveling battery is completed. Charging can be realized with a simple configuration. As a result, it is possible to prevent a situation where the battery of the auxiliary battery in the plug insertion state is raised without increasing the cost.

  In addition, it is possible to optimize the charging of the auxiliary battery by making it possible to change the monitoring time during the additional charging to the auxiliary battery according to the charging state of the auxiliary battery at the time of the previous additional charging. It becomes possible.

It is a system configuration figure of an embodiment. It is explanatory drawing of a control pilot signal. It is a flowchart of a 1st embodiment. It is a flowchart of a 2nd embodiment. It is operation | movement explanatory drawing of 2nd Embodiment.

Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.
This embodiment prevents consumption of an auxiliary battery in a vehicle charging system that charges an EV vehicle or the like from a charging station.

FIG. 1 is a system configuration diagram of this embodiment.
A vehicle 100 such as an EV vehicle includes an auxiliary battery 101, a traveling battery 102, a charger 103, a charge control circuit 104, a communication circuit 105, a connector 106, and another ECU (engine control unit) 107. The auxiliary battery 101 is a small capacity battery for driving electronic / electrical circuits of various auxiliary machines such as a headlight and a clock in the vehicle 100. The traveling battery 102 is a large capacity battery for driving a traveling motor of the vehicle 100. The charger 103 charges the auxiliary battery 101 and the traveling battery 102 with electric power supplied from the charging station 200 via the external power cable 400, the plug 401, the connector 106, and the internal power cable 108. The charging control circuit 104 monitors the charging state in the charger 103. The communication circuit 105 is connected to the charge control circuit 104, and exchanges charge control information such as charge monitoring result information with the charging station 200 based on a power line communication method or the like via the internal power cable 108 and the external power cable 400. Send and receive with. The other ECU 107 is a computer unit for controlling a traveling system such as an engine. The charger 103, the charging control circuit 104, the communication circuit 105, and the other ECU 107 are connected to each other by a CAN (car area network) 109 that is a digital communication cable.

  The charging station 200 includes a charging circuit 201 and a communication circuit 202. When charging station 200 and vehicle 100 are connected by external power cable 400, plug 401, and connector 106, the following operation is performed. The communication circuit 202 transmits and receives charging control information based on the communication circuit 105 in the vehicle 100 and a power line communication method via the internal power cable 108 and the external power cable 400. Charging circuit 201 supplies electric power from commercial power source 300 such as a household power source to vehicle 100 when communication circuit 202 receives charging control information instructing the start of charging from communication circuit 105 in vehicle 100. That is, the charging circuit 201 supplies power to the charger 103 in the vehicle 100 via the external power cable 400, the plug 401, the connector 106 in the vehicle 100, and the internal power cable 108. Charging circuit 201 stops the supply of power to vehicle 100 when communication circuit 202 receives charging control information instructing the end of charging due to full charging from communication circuit 105 in vehicle 100. However, the charging circuit 201 continues to supply the control pilot signal to the charger 103 in the vehicle 100 while the plug 401 is connected to the connector 106 of the vehicle.

  FIG. 2 is an explanatory diagram of a control pilot signal (hereinafter referred to as “CPLT signal”) supplied from the charging circuit 201 in the charging station 200 to the charger 103 in the vehicle 100. The CPLT signal continues to be supplied from the charging circuit 201 to the charger 103 until the plug 401 of the external power cable 400 is connected to the connector 106 and then the plug 401 is removed from the connector 106.

  The CPLT signal is a pulse signal that changes between +6 V (volts) and −12 V during the period during which the battery for traveling 102 and the auxiliary battery 101 are being charged (FIG. 2A). The pulse width of the CPLT signal changes according to the power capacity that can be supplied by the charging circuit 201.

  When the communication control circuit 105 in the vehicle 100 notifies the communication circuit 202 in the charging station 200 of a charge control signal for completion of charging due to the full charge of the traveling battery 102, the CPLT signal is as shown in FIG. The pulse signal changes between + 9V and −12V.

Thereafter, when the plug 401 is removed from the connector 106, as shown in FIG. 2C, the CPLT signal received by the charger 103 in the vehicle 100 becomes 0V.
In order to determine whether or not the plug 401 has been removed from the connector 106, the charger 103 must receive the CPLT signal in the state of FIG. For this reason, in the plug insertion period after full charge shown in FIG. 2B, the charger 103 cannot enter a complete sleep state, and the auxiliary battery 101 to the charger 103, the charge control circuit 104, and the communication circuit. It is necessary to supply power to 105. If the plug 401 is removed from the connector 106 and the CPLT signal becomes 0V, the charger 103 can be in a complete sleep state. Only at this stage can the power supply from the auxiliary battery 101 to each circuit be stopped.

  After entering the sleep state, the wake-up is performed by the interruption of the CPLT signal, and power is supplied from the auxiliary battery 101 to the charger 103, the charge control circuit 104, and the communication circuit 105. As a result, as shown in FIG. 2 (d), the charger 103 receives the CPLT signal from the charging station 200, and the charging battery 201 and the auxiliary battery 101 can be charged from the charging circuit 201. Become.

  This embodiment is a technique that enables charging from the charging station 200 to the auxiliary battery 101 intermittently in a state where the plug 401 is fully charged after the battery 102 for traveling in FIG. 2B is fully charged. FIG. 3 is a flowchart of the first embodiment showing a control operation for realizing this operation. The control operation shown in this flowchart is realized as an operation in which a CPU (central processing unit) (not shown) constituting the charging control circuit 104 of FIG. 1 executes a control program stored in a memory (not shown).

  3 is started by the charging control circuit 104 when the charger 103 starts receiving the CPLT signal, wakes up, and enters the state of FIG.

The charging control circuit 104 is in a standby state until the charging state of the charger 103 is fully charged (repetition of NO determination in step S301).
When the charging state is fully charged and charging is completed and the determination in step S301 is YES, the charging control circuit 104 activates an intermittent operation function (timer) for monitoring a certain period after the charging ends (full charging). (Step S302).

  Next, the charging control circuit 104 determines whether or not the plug 401 has been removed from the connector 106 (step S303). This determination operation is an operation for determining whether or not the CPLT signal received by the charging circuit 201 has reached 0 V (whether or not the period of FIG. 2C has been entered). The charge control circuit 104 that executes this process operates as a plug connection state detection unit.

  If the plug 401 has not been removed and the determination in step S303 is NO, the charging control circuit 104 monitors the intermittent operation function (timer) activated in step S302 to determine whether or not a certain period of time has elapsed after the end of charging. Is determined (step S304).

If the predetermined period has not elapsed after the end of charging and the determination in step S304 is NO, the charging control circuit 104 returns to the operation for determining whether the plug 401 is inserted or removed in step S303.
When a predetermined period has elapsed after the end of charging (including supplementary charging) in a state where the plug 401 is not removed from the connector 106, and the determination in step S304 is YES, the charging control circuit 104 instructs charging start with a low current. Information is notified to the communication circuit 202 in the charging station 200 via the communication circuit 105. The charging control circuit 104 notifies the communication circuit 202 in the charging station 200 via the communication circuit 105 of charging control information for instructing the end of charging when a fixed predetermined time has elapsed after this notification. During this time, the charging control circuit 104 instructs the charger 103 to charge only the auxiliary battery 101. As a result, electric power with a low current is supplied from the charging circuit 201 in the charging station 200 to the charger 103 in the vehicle 100 for a fixed predetermined period. Then, the charger 103 performs additional charging to the auxiliary battery 101 for a fixed predetermined period based on the low current power. The fixed predetermined period is a period necessary and sufficient to charge the auxiliary battery 101 from the charging station 200 with electric power suitable for consumption by the auxiliary battery 101 within the predetermined period determined in step S304. The charge control circuit 104 that executes this process operates as a supplementary charging unit.

After the addition charging for the predetermined period is completed, the charging control circuit 104 returns to the activation of the intermittent operation function in step S302.
If the plug 401 is removed from the connector 106 during the fixed monitoring period and the determination in step S303 is YES, the charging control circuit 104 clears the intermittent operation function (timer) activated in step S302 (step S306).

  Then, the charging control circuit 104 shifts to a sleep state in which only the interruption of the CPLT signal is monitored while minimizing power consumption, and the charging control operation is terminated (step S307). As a result, the power consumption in the auxiliary battery 101 becomes almost zero, and the battery is prevented from rising.

  As described above, according to the first embodiment of the control operation by the charging control circuit 104, the charging is performed each time a certain period elapses while the plug 401 is inserted into the connector 106 after the charging of the traveling battery 102 is completed. It becomes possible to add and charge the auxiliary battery 101 in the vehicle 100 from the station 200 every predetermined time. In the first embodiment, by simply providing a simple relay switch for charging only the auxiliary battery 101 in the charger 103, it is possible to realize additional charging to the auxiliary battery 101 without increasing the cost. In addition, it is possible to prevent a situation in which the battery of the auxiliary battery 101 rises in the plug insertion state.

  FIG. 4 is a flowchart of the second embodiment showing a control operation that enables charging of the auxiliary battery 101 in the inserted state of the plug 401 after the battery 102 for full running is inserted. The control operation shown in this flowchart is also realized as an operation in which a CPU (not shown) constituting the charging control circuit 104 of FIG. 1 executes a control program stored in a memory (not shown). In the flowchart of FIG. 4, the same steps as those in FIG.

  The control operation of FIG. 4 is different from that of FIG. 3 in that the monitoring time during addition charging to the auxiliary battery 101 can be changed according to the charging state of the auxiliary battery 101 at the time of previous addition charging. In other words, the charging of the auxiliary battery 101 is optimized.

  Specifically, when the determination in step S301 becomes YES after the fully charged battery 102 has been fully charged, or after the process in step S402 described later after the last supplementary charging in step S305, the charge control circuit. 104 calculates the monitoring time until the current addition charging as follows (step S401). That is, as shown in the explanatory diagram of FIG. 5, the charging control circuit 104 monitors the time until the current additional charging based on the additional charging voltage recorded during the previous additional charging in the process of step S <b> 402 described later. (Standby time) is calculated. More specifically, the charging control circuit 104 controls the monitoring time so that it is long when the previous charging voltage is high and short when it is low. This control may be determined based on a function table indicating a relationship between a charging voltage and a monitoring time prepared in advance, or may be determined by classifying the monitoring time based on a threshold value of the charging voltage. The charging control circuit 104 sets the monitoring time to a predetermined time when charging is performed for the first time after the running battery 102 is fully charged.

In S302 ′ corresponding to step S302 in FIG. 3, the charging control circuit 104 activates the intermittent operation function (timer) with the monitoring time calculated in step S401.
In the second embodiment, when the charging capacity of the auxiliary battery 101 is large and the charging voltage at the time of charging is high, the monitoring time until the next additional charging is extended, and when the charging capacity is low and the charging voltage is low, the next additional charging is performed. It is possible to control the monitoring time up to short. In this way, the charging of the auxiliary battery 101 is optimized.

  In the second embodiment described above, the monitoring time during addition charging to the auxiliary battery 101 is changed and controlled in accordance with the charging state of the auxiliary battery 101 at the time of the previous additional charging. On the other hand, if the monitoring time is constant, the charging time at the time of additional charging can be changed and controlled. Alternatively, both the monitoring time and the charging time may be controlled.

DESCRIPTION OF SYMBOLS 100 Vehicle 101 Auxiliary battery 102 Battery for traveling 103 Charger 104 Charge control circuit 105, 202 Communication circuit 106 Connector 107 Other ECU (engine control unit)
108 Internal power cable 109 CAN (car area network)
200 Charging Station 201 Charging Circuit 202 Communication Circuit 300 Commercial Power Supply 400 External Power Cable 401 Plug

Claims (5)

By connecting a plug of a power cable connected to a charging station to a connector of a vehicle, power is supplied from the power cable to a charger for charging a traveling battery and an auxiliary battery in the vehicle, and the charging stand and the charging station In a vehicle charging system that communicates charging control information related to a charging operation with a vehicle,
A plug connection state detection unit for detecting a state in which the plug is connected to the connector after charging of the traveling battery;
When the predetermined monitoring time elapses in the connected state of the plug, the charging station is instructed to charge the auxiliary battery for a predetermined charging time, whereby the predetermined charging is performed from the charging station to the charger. An additional charging unit that feeds time and causes the charger to charge the auxiliary battery; and
A vehicle charging system comprising: The plug connection state detection unit detects a state in which the charging to the battery for traveling is completed in the charger and then detects a state in which a control pilot signal is supplied from the charging station to the charger. Detecting a state in which the plug is connected to the connector;
The vehicle charging system according to claim 1. The additional charging unit is
Record the charging voltage to the auxiliary battery in the charger,
The current predetermined monitoring time is calculated based on the previous charging voltage.
The charging system for vehicles according to claim 1 or 2 characterized by things. Communication of the charging control information between the charging station and the vehicle is PLC communication performed using the power cable.
The vehicle charging system according to any one of claims 1 to 3, wherein By connecting a plug of a power cable connected to a charging station to a connector of a vehicle, power is supplied from the power cable to a charger for charging a traveling battery and an auxiliary battery in the vehicle, and the charging stand and the charging station In a vehicle charging method for communicating charging control information related to a charging operation with a vehicle,
Detecting a state in which the plug is connected to the connector after charging of the traveling battery is completed,
When the predetermined monitoring time elapses in the connected state of the plug, the charging station is instructed to charge the auxiliary battery for a predetermined charging time, whereby the predetermined charging is performed from the charging station to the charger. Power the time and let the charger charge the auxiliary battery,
A vehicle charging method.

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