JP3214045B2 - Charging device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charging device for charging a storage battery mounted on, for example, an electric vehicle.

[0002]

2. Description of the Related Art An electric vehicle uses a motor as a motor and a secondary battery (rechargeable battery) as a power source for the motor. For this reason, unlike an internal combustion engine automobile, it is necessary to charge a mounted storage battery instead of supplying fuel such as gasoline.
In order to spread electric vehicles, it is important to strengthen the maintenance aspect. For example, charging equipment for storage batteries must be placed on public roads, and a system capable of charging storage batteries in a short time with these charging equipment must be established. From such a viewpoint, improvements and researches on a charging device, a quick charging method, and the like are currently in progress.

FIG. 2 schematically shows a conventional charging device for an electric vehicle. 1 is a charging device, and 2 is an electric vehicle. The charging cable 3 is connected to the external connection terminals A and B of the charging device 1. By connecting the charging cable 3 to the external connection terminals A 'and B' of the electric vehicle 2,
The storage battery 4 mounted on the electric vehicle 2 is charged.

The charging device 1 takes in AC power from an AC power supply 5 via circuit breakers 6 and 6, converts the AC power to DC by a rectifier 7, and outputs the DC power to external connection terminals A and B via switch contacts 8 and 8. I do. Control device 9 controls rectifier 7 based on the DC current and DC voltage detected by current detector 10 and voltage detector 11, and charges storage battery 4 by a predetermined charging method.

[0005]

As described above, this type of charging device 1 is connected to an electric vehicle 2 via a charging cable 3.
When the charging cable 3 is disconnected from the electric vehicle 2 and the supply of the charging power is started, the conductor contacts the connection terminal of the charging cable 3 because the charging cable 3 is connected to the charging side. Short circuit occurs and the charging device 1
There was a possibility that a short-circuit current would flow in the internal circuit of.

The present invention has been made in view of the above circumstances, and in a charging device for charging a storage battery mounted on an electric vehicle or the like, the supply of charging power when the charging cable is disconnected is reliably avoided, and It is an object of the present invention to provide a battery that can reliably prevent charging when a connection terminal is short-circuited.

[0007]

SUMMARY OF THE INVENTION The present invention provides
In order to achieve the above object, a DC converter that converts power supplied from a power supply into DC and a connector connected to an output terminal of the DC converter are provided on the charger side,
The following means is provided in a charging apparatus provided with a connector connected to a terminal of a storage battery on a charging side and connecting a charging cable to a connector on the charger side and a connector on the charging side.

That is, a capacitor is connected between the terminals of the connectors on the charger side and on the charged side to form an AC circuit. Then, before the start of charging, the AC power supply is operated to apply an AC voltage to the AC circuit. If the connectors on the charger side and on the side to be charged are connected via a charging cable, an AC current flows by applying an AC voltage. Therefore, the AC current detector monitors whether or not an AC current flows, and after confirming that the AC current is correctly connected, starts charging.

If the capacity of the capacitor connected to the electric vehicle is set according to the type of the vehicle, the type of the vehicle to be charged can be determined from the current value detected by the AC current detector.
The rectifier control unit that controls the charging pressure current can be charged under conditions suitable for the vehicle to be charged.

[0010]

Embodiments of the present invention will be described below.

FIG. 1 shows an outline of a charging apparatus according to an embodiment of the present invention. In the figure, the same or corresponding parts as those in the related art are denoted by the same reference numerals, and description thereof is omitted. In the charging device 1, the power receiving point of the AC power
Is connected. This transformer 12 has a winding 1 on the secondary side.
2A and 12B. The winding 12 </ b> A is connected to the input terminal of the rectifier 7. An AC circuit including a winding 12B, a DC blocking capacitor 13, and a contact 14 is formed between the external connection terminals A and B. This AC circuit is provided with an AC current detector 15 for detecting an AC current. Further, the control device 9 has a function of determining the connection state of the charging cable from the detection output of the AC current detector 15 in addition to the control function of the rectifier 7 and the control function of various switches. Rectifier control unit 9
-1, a relay control unit 9-2 and a connection determination unit 9-3. The relay 16 opens and closes the contacts 8 and 8, and the relay 17 opens and closes the contacts 14. The operation switch 18 is for inputting a connection confirmation instruction. On the other hand, in the electric vehicle 2, a DC blocking capacitor 19 is connected between the external connection terminals A 'and B'.

In the above configuration, charging is performed after the charging cable 3 is connected to the external connection terminals A 'and B' of the electric vehicle 2. In this embodiment, the connection state of the charging cable 3 is checked before starting charging. I can do it. When the operator wants to check the connection state, he / she presses the operation switch and inputs a connection state confirmation instruction to the charging device 1. Thereby, the connection determination unit 9-3 starts the connection determination process.

In this process, first, the relay 17 is operated by the relay control section 9-2 to turn on the contact 14. Thereby, the AC voltage of the winding 12B is changed to the external connection terminals A,
B is applied. When the charging cable 3 is connected to the electric vehicle 2, the winding 12B → the contact 14 → the capacitor 15 → the terminal A → the terminal A ′ → the capacitor 19 → the terminal B ′
An AC current flows through an AC circuit composed of a path from a terminal B to a winding 12B, and the AC current is detected by the AC current detector 15. This AC voltage may be a low voltage of, for example, about 5V. When this AC current is detected, the connection determination unit 9-3 determines that the charging cable 3 is normally connected, notifies the relay control unit 9-2 of permission to make the contacts 8, 8, and The rectifier control unit 9-1 is notified of permission to start charging. After receiving these permissions, the relay control unit 9-2
Operates the relay 16 to turn on the contacts 8, 8, and the rectifier control unit 9-1 drives the rectifier 7 to start charging.
If no AC current is detected, the connection determination unit 9-
3 determines that the charging cable 3 is not properly connected, and executes, for example, an alarm output process. In this case, the rectifier control unit 9-1 and the relay control unit 9-2 are not notified of the permission, and thus charging is not started.

[0014]

As described above, according to the present invention, charging is started after applying an AC voltage before starting charging to determine whether or not the charging cable is normally connected. The charging operation with the cable disconnected can be avoided. Therefore, damage to the internal circuit due to short-circuiting of the connection terminal of the charging cable can be reliably prevented.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an outline of a charging device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing an outline of a conventional charging device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Charging device 2 ... Electric vehicle 3 ... Charging cable 4 ... Storage battery 7 ... Rectifier 9-3 ... Connection determination part 12 ... Transformer 13 ... Charging device side capacitor 14 ... Contact point of AC circuit 15 ... AC current detector 16 ... Relay 19: Capacitor on the electric vehicle side

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-3141 (JP, U) (58) Fields surveyed (Int. Cl. ⁷ , DB name) H02J 7/00-7/12 H02J 7 / 34-7/36 B60L 11/18

Claims (2)

(57) [Claims] A DC converter for converting power supplied from a power supply into DC, a connector connected to an output terminal of the DC converter on a charger side, and a connector connected to a terminal of a storage battery. And a charging cable connected to a connector on the charger side and a connector on the charging side, wherein a capacitor is connected between terminals of the respective connectors on the charger side and the charging side, and AC power is supplied. The circuit comprises an AC power supply section for applying an AC voltage to the AC circuit before charging, and an AC current detecting section for detecting the presence or absence of an AC current flowing in the AC circuit. A charging device that starts charging when the battery is charged. 2. The charging device according to claim 1, wherein the capacity of the capacitor connected between the terminals is selected for each vehicle type, and the vehicle type is determined based on a value of the alternating current.