JP2010110055A - Charging cable for electric vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a low-cost charging cable for electric vehicles that detects abnormal heating or an electric leak and interrupts the supply of charging power. <P>SOLUTION: The charging cable 1 for electric vehicles includes: a power plug 3 connected to an electrical outlet of commercial power; a temperature sensor 13 that detects the temperature of the power plug; a connector 4 for vehicles that is connected to a vehicle-side connector of an electric vehicle and supplies commercial power; a switching circuit 12 that opens and closes the electric pathway between the power plug and the connector for vehicles; and a control circuit 11 having an electric leak detection unit 14 that detects an electric leak based on the current passed through the electric pathway. When a temperature signal outputted by the temperature sensor 13 exceeds a predetermined temperature or the electric leak detection unit 14 detects an electric leak while the battery of an electric vehicle is being charged, the control circuit 11 transmits a control signal to the switching circuit 12. As a result, the supply of commercial power from the power plug 3 to the connector 4 for vehicles is stopped. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a charging cable used for charging a battery of an electric vehicle.

  In recent years, electricity such as hybrid vehicles that travel using both power stored in the secondary battery as a power source and fuel such as gasoline, and secondary battery vehicles that travel using the power continuously discharged from the secondary battery as a power source. Automobiles are in practical use. Among these electric vehicles, there are also electric vehicles (for example, plug-in hybrid cars) that charge a battery by receiving power supply from a commercial power source supplied to each household. An electric vehicle charging cable is used to connect the power outlet to the connector on the electric vehicle side.

  As this type of battery, for example, a battery that requires a high voltage of about 200V to 300V is used, and when charging, a high voltage of 200V is often used as a commercial power source. Safety is required for the charging cable.

  By the way, in an ordinary home, an electric vehicle is often parked in an outdoor parking space or a car port installed outdoors. For this reason, when charging the battery of an electric vehicle, insert the power plug of the charging cable for the electric vehicle into a retaining-type waterproof power outlet installed on the outer wall of the house, etc. Recharge the battery with the supply. On the other hand, when the electric vehicle is not charged, such as when going out with an electric vehicle, for example, it can be assumed that the charging cable for the electric vehicle is housed indoors or inside the electric vehicle (for example, a trunk). That is, the electric vehicle charging cable is inserted into and removed from a waterproof power outlet every time it is used.

  However, non-removable waterproof power outlets that are installed on the outer wall of a house are usually designed on the assumption that the plug will be used for a long period of time. There was a possibility that abnormal heat generation etc. might occur by the simple connection. In addition, since the humidity is high outside and there is a lot of dust and dirt, there is a possibility of abnormal heat generation due to the tracking phenomenon.

In view of this, a power feeding coupler has been proposed in which abnormal heat generation is prevented by detecting an increase in temperature during battery charging and stopping power feeding (for example, Patent Document 1). The power feeding coupler disclosed in the above document includes a thermistor as a temperature detecting means in a case in which a primary coil is built in. When the power feeding coupler exceeds a set temperature, a temperature abnormality is detected by an increase in resistance of the thermistor. The power supply is stopped.
JP 2001-160518 A

  In addition to abnormal heat generation due to poor connection or tracking phenomenon, if leakage occurs during charging using the high voltage as described above, there is a possibility that overcurrent flows and stress is applied to the battery or the charging circuit. Therefore, it is necessary to avoid abnormal heat generation and leakage by combining a plurality of means, for example, by using a leakage breaker in the power supply path of the power supply coupler and commercial power supply of Patent Document 1, and the cost of the equipment to be used is reduced. There was a problem that it was expensive and time-consuming to install.

  The present invention has been made in view of the above-mentioned reasons, and an object of the present invention is to provide a low-cost electric vehicle charging cable that can detect abnormal heat generation or leakage and cut off charging. There is.

  In order to achieve the above object, an electric vehicle charging cable is an electric vehicle charging cable for charging an electric vehicle battery using a commercial power source, and is a power source detachably connected to a commercial power source outlet. A plug, temperature detection means for detecting the temperature of the power plug, a vehicle connector that is detachably connected to the electric vehicle and supplies a charging current to the battery, and an open / close that opens and closes an electric circuit between the power plug and the vehicle connector Means, a leakage detecting means for detecting a leakage based on the current flowing in the recording circuit, and when the detected temperature of the temperature detecting means exceeds a predetermined threshold or the leakage detecting means detects a leakage, the switching means is opened. And an electric power cut-off means.

  Here, an electric vehicle refers to a hybrid vehicle (for example, a plug-in hybrid car) that travels by using a combination of electric power stored in a secondary battery and a fuel such as gasoline as a power source, and electric power that is discharged to the secondary battery. A vehicle using a secondary battery as a part or all of a power source, such as a secondary battery vehicle that travels using as a power source.

  According to the first aspect of the present invention, the temperature detection means can detect an abnormal rise in temperature, the leakage detection means can detect a leakage, and either the temperature detection means or the leakage detection means has an abnormality. When detected, the power interruption means opens the supply path and cuts off the electric power, so that it is possible to prevent an overcurrent from flowing due to abnormal heat generation or leakage due to poor connection or tracking phenomenon.

  In addition, since the power interruption means detects an abnormality from both the temperature detection means and the leakage detection means and opens the supply path, there is no need to provide a plurality of opening and closing means, and both detection means share the opening and closing means. By doing so, a low-cost charging cable for an electric vehicle can be provided.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic circuit diagram of a charging cable for an electric vehicle according to the present embodiment, and FIG. 2 is a diagram showing a use example in which a battery for traveling of the electric vehicle is charged using the charging cable for the electric vehicle. It is. Fig.3 (a) is a perspective view which shows the principal part of the charging cable for electric vehicles, and FIG.3 (b) is sectional drawing of the principal part.

  As shown in FIG. 2, the electric vehicle charging cable 1 connects between a power outlet 7 provided on the outer wall of a house and a vehicle-side connector 9 of the electric vehicle 8 parked in a parking space outside the house. It is used for charging the battery 10 for traveling mounted on the electric vehicle 8.

  The power outlet 7 has, for example, a retaining structure that prevents the power plug from falling off due to its own weight, and also has a waterproof structure that prevents a short circuit of the electrode due to rain water or the like. The power outlet 7 is a socket with a two-pole grounding electrode standardized by JIS C 8303, and is connected to a commercial power source (not shown) that supplies a single-phase two-wire AC 100V. A vehicle-side connector 9 provided in the electric vehicle 8 and a battery 10 mounted on the electric vehicle 8 are connected via a power cable (not shown) and a charging circuit (not shown), and the charging When the circuit receives supply of commercial power from the vehicle-side connector 9, the battery 10 is charged.

  The electric vehicle charging cable 1 includes a power plug 3 that can be detachably connected to a power outlet 7, a vehicle connector 4 that is connected to a vehicle-side connector 9 to supply power, and a power plug 3 and a vehicle connector 4 And a control cable 2 provided in the middle of the power cable 5.

  The power plug 3 includes connection terminals 31, 31, and 32, and cables L1, L1, and L2 included in the power cable 5a are connected to the connection terminals 31, 31, and 32, respectively. The connection terminals 31 and 31 are terminals that receive AC power from the power outlet 7, and the connection terminal 32 is a grounding terminal. Further, the power plug 3 has a temperature sensor 13 made of, for example, a resistance temperature detector embedded therein (see FIG. 3), and the temperature signal of the temperature sensor 13 is sent to the control circuit 11 via signal lines L3 and L3. Is output. The cables L1, L1, L2 and the signal lines L3, L3 are bundled and covered with an insulating material to constitute the power cable 5a.

The control box 2 includes an open / close circuit 12 for opening and closing the cables L1 and L1 which are electric paths between the power plug 3 and the vehicle connector 4, and an open circuit via the open / close circuit 12 when an abnormality is detected during charging. And a control circuit 11 for stopping the supply of commercial power.

  The control circuit 11 is connected to the cables L 1, L 1, and L 2, and operates using commercial power supplied via the cables L 1, L 1, and L 2 as an operating power source for the control circuit 11. The control circuit 11 also includes a leakage detection unit 14 that detects current leakage by monitoring currents flowing on the cables L1 and L1. When the leakage detection unit 14 detects leakage, the control circuit 11 is connected to the switching circuit 12. Send a signal containing an instruction to open. The control circuit 11 and the temperature sensor 13 are connected via a signal line L3. When the temperature signal input from the temperature sensor 13 is equal to or higher than a predetermined temperature, the control circuit 11 sends the control circuit 11 to the switching circuit 12. Send a signal containing an instruction to open the circuit. That is, the control circuit 11 and the temperature sensor 13 form a temperature detection unit, and the leakage detection unit 14 of the control circuit 11 forms a leakage detection unit.

  The opening / closing circuit 12 has switches SW, SW for opening / closing the cables L1, L1, receives a signal from the control circuit 11, opens / closes the switch SW, and supplies commercial power from the power plug 3 to the vehicle connector 4. Turn the supply off / on.

  Here, when the power plug 3 is connected to the power outlet 7, power from the commercial power supply is supplied to the control circuit 11 via the cables L1 and L2. In addition, since the open / close circuit 12 is in an on state in the initial state, power from the commercial power source is supplied to the vehicle connector 4, and the vehicle connector 4 is connected to the vehicle side connector 9, thereby charging the battery 10. Done. At this time, the control circuit 11 operates based on the electric power from the commercial power source, and measures the temperature detected by the temperature sensor 13 and the current or voltage in the circuit.

  At this time, if dust or dirt containing moisture accumulates in the power outlet 7 or the power plug 3 to reduce the insulation between the terminals, or if heat is generated due to poor contact between the power outlet 7 and the power plug 3, The detection temperature of the sensor 13 increases. When the detected temperature from the temperature sensor 13 exceeds the temperature preset in the control circuit 11, the control circuit 11 transmits a signal for cutting off power to the switching circuit 12. The open / close circuit 12 receives the signal, opens the switch SW, interrupts the current flowing through the cable L1, and stops the charging of the battery 10.

  On the other hand, when the battery 10 is charged as described above, if a leakage occurs due to damage to the vehicle-side connector 9 or the power cable 5, the control circuit 11 detects the leakage and supplies power to the switching circuit 12. Send a signal to shut off. When the open / close circuit 12 receives the signal, the switch SW is opened and the current flowing through the cable L1 is cut off, so that the charging of the battery 10 is stopped. In addition, about the detection method of an electrical leakage, since it is a known technique, description is abbreviate | omitted.

  In this way, when the battery 10 is charged, if the temperature of the power plug 3 or a leakage occurs, the control circuit 11 can detect them and immediately stop charging, so the battery 10 can be charged safely. I can do it. Moreover, since the switching circuit 12 is shared by the temperature sensor 13 and the control circuit 11 which are temperature detection means and the leakage detection unit 14 which is leakage detection means, a low-cost electric vehicle charging cable can be provided. .

  In this embodiment, the commercial power supply is AC 100V, but may be a high-voltage power supply such as AC 200V. At this time, the power plug 3 has a shape corresponding to the voltage of the power source and may be detachably connected to the power outlet 7.

1 is a schematic circuit diagram of a charging cable for an electric vehicle according to an embodiment of the present invention. Schematic showing the usage state of the charging cable for the electric vehicle (A) is a perspective view which shows the principal part of the charging cable for electric vehicles, (b) is sectional drawing of the (a).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Charging cable for electric vehicles 2 Control box 3 Power plug 4 Vehicle connector 5a, 5b Power cable 11 Control circuit (power cutoff means)
12 Open / close circuit (open / close means)
13 Temperature sensor (temperature detection means)
14 Earth leakage detector (earth leakage detection means)
31 connection terminal 32 connection terminal (ground terminal)
SW switch L1 cable L2 cable L3 Signal line

Claims (1)

A power plug that is detachably connected to a commercial power outlet,
Temperature detecting means for detecting the temperature of the power plug;
A vehicle connector that is detachably connected to the electric vehicle and supplies a charging current to the battery of the electric vehicle;
Opening and closing means for opening and closing an electric circuit between the power plug and the vehicle connector;
A leakage detecting means for detecting a leakage based on a current flowing through the circuit;
Charging for an electric vehicle, comprising: a power cut-off means for opening the opening / closing means when the detected temperature of the temperature detection means exceeds a predetermined threshold value or the leakage detection means detects a leakage. cable.

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