JP6226567B2 - Battery charging system for electric vehicles - Google Patents

Description

  The present invention relates to a system for charging a battery mounted on an electric vehicle such as an electric vehicle, and in particular, a plurality of units that efficiently use power supplied from a natural energy power generation facility such as solar power generation or wind power generation or a power system. The present invention relates to a system for charging a vehicle battery.

  An electric vehicle such as an electric vehicle (in addition to an electric vehicle, an electric motorcycle, a light vehicle, a work vehicle, an agricultural machine, a bicycle, and the like. Hereinafter, simply referred to as an “electric vehicle”) is electric power stored in an installed battery. Is used as a power source (a power source using fuel such as gasoline may be used in combination). The electric vehicle can be operated continuously by performing battery charging at charging stations (see FIG. 1 of Patent Document 2) provided at various places.

  Conventionally, as a vehicle battery charging system, Patent Document 1 discloses that in a charging system having a plurality of vehicle battery charging devices, the total current exceeds the load capacity of the external power source by adjusting the charging current of each charging device. A system that can be charged without skipping the breaker without the user confirming the state of the load connected to the power supply facility by automatically controlling the power supply equipment is disclosed.

  Further, in Patent Document 2, in a charging system having a plurality of vehicle battery charging devices, vehicle information is acquired from each vehicle, a priority order is determined according to the purpose of use of the vehicle, and the battery is supplied to the battery of each vehicle. A system for controlling the amount of power to be disclosed is disclosed.

JP 2003-333706 A JP 2010-110173 A

  As described above, in a charging station having a plurality of vehicle battery charging devices, it is necessary to efficiently allocate a limited amount of supplied power to the plurality of charging devices. Normally, the amount of power supplied from the commercial power system cannot exceed a certain capacity, so when a large number of vehicles charge at the charging station, it is inevitable that the power will be insufficient, and it takes time to charge. There will be a traffic jam in the vehicle waiting for. This is a problem that is not fundamentally solved no matter how the power supply amount is allocated as in the above-described prior art.

  On the other hand, in recent years, natural energy power generation such as solar power generation and wind power generation has been developed and put to practical use. The method of using the electric power generated in the conventional natural energy power generation facility is to supply the commercial power system and sell it to the electric power company, or install the storage battery facility and store it for use as needed. It was common. However, the former only has the advantage of reducing the power cost of the equipment, and the latter is useful for temporary power supply in the event of a power outage disaster, but the generated power is wasted after full charge, and natural energy is lost. It could not be said that the power generated by power generation could be used so effectively.

As a result of diligent research in view of such circumstances, the present inventors have effectively utilized natural energy by supplying electric power generated in natural energy power generation facilities such as solar power generation and wind power generation to a charging station of an electric vehicle. Inspired to be able to do.
In charging stations where electric power demand is generated by battery charging of electric vehicles at all times or intermittently, supply by using power directly from natural energy power generation facilities together with or instead of the commercial power system It is possible to prevent the capacity of the electric power from being exceeded and to charge the batteries of a plurality of electric vehicles efficiently and speedily in parallel.

As a method for controlling the charging current in the conventional charging station, the charging current value is a fixed value and the supply power source in each charging device is turned on / off by a relay, and a preset total as in the example of Patent Document 1 is used. There is a method of adjusting the allocation of the current value to each charging device within the range of the current limit value. However, when receiving power from the natural energy power generation facility at the charging station, the power cannot be efficiently used according to the amount of power output changing from the natural energy power generation facility by any of the above methods.
Therefore, the present inventors have devised a mechanism for controlling the current value to each charging device according to the amount of power supply that changes every moment in a charging station that receives power supply from a natural energy power generation facility, thus forming the present invention. Has been reached.

Specifically, the present invention is a battery charging system for an electric vehicle that receives power supply from a natural energy power generation facility and charges a battery mounted on a plurality of electric vehicles, and is output from the natural energy power generation facility. A power conditioner that rectifies and outputs power, a distribution board that receives power output from the power conditioner, distributes the power to a plurality of charging stations, and one or more charging connectors for an electric vehicle has, receives power from the distribution board, and a plurality of charging stand for transmitting an arbitrary charging current to the each charging connector, the ability to get the generation power output value from the power conditioner, and the respective charging stations And / or a charge controller having a function of determining a charging current to be assigned to each charging connector, and the power condition A battery charging system for an electric vehicle is provided that can be controlled so as to dynamically change a charging current assigned to each charging station and / or each charging connector in accordance with a change in a generated power output value in the vehicle. is there.

  Here, to charge multiple electric vehicles according to the generated power output of the natural energy power generation facility, the electric vehicle currently charging the generated power output of the natural energy power generation facility obtained from the power conditioner and waiting for charging By dividing by the number of electric vehicles, a charging current value that can be used for charging per electric vehicle can be calculated, notified to each electric vehicle, and charged. By repeating this, charging according to the generated power output becomes possible. In addition, as a means for notifying the electric vehicle of the current value, a method of transmitting a DUTY ratio by a PWM signal on a CPLT line defined by SAE J1772 which is a known technique, or a CAN mounted on an electric vehicle, etc. Communication means may be used.

  In the battery charging system for an electric vehicle of the present invention, it has means for receiving power supply from a power system different from the natural energy power generation facility, and when the generated power output value in the power conditioner is less than the required amount, Charging is performed by receiving power supply from the different power systems.

  In this way, when the generated power of the natural energy power generation facility used for charging is not sufficiently obtained, for example, when the solar power generation facility has poor weather conditions such as nighttime, cloudy weather, and rainy weather, sufficient generated power cannot be obtained. This problem can be solved by using commercial power grid power together for charging.

In the battery charging system for an electric vehicle according to the present invention, even when the generated power output value in the power conditioner is less than a predetermined required amount, the power supply from the different electric power system is below a predetermined limit value. It is characterized by controlling as follows.
Further, in a state where the power supply from the different power system is received, when the generated power output value in the power conditioner reaches a predetermined required amount, the power supply from the different power system is received. It is characterized by stopping.

  In this way, the use of natural energy is prevented by preventing the use of power from commercial power grid power without restriction, and when the weather recovers later, priority is given to the power generated by the natural energy power generation facility. Efficiency can be maximized.

  In the battery charging system for an electric vehicle according to the present invention, the charge controller calculates a charging capacity required for a battery mounted on each electric vehicle being charged, and a generated power output value in the power conditioner is a predetermined required amount. The charging time required to complete the charging of each electric vehicle with the minimum electric power that can be used for charging in the case of less than the above is calculated, and the charging start calculated backward from the completion time and the charging time preset for the electric vehicle Time is calculated and it controls to start charge automatically at the said charge start time.

  Thereby, even if it is a case where the electric power generation of a natural energy power generation facility is not fully obtained, charge can be completed at the charge completion time which the user preset.

  In the battery charging system for an electric vehicle according to the present invention, the charging controller periodically calculates the charging capacity necessary for the battery mounted on each electric vehicle being charged, and to the vehicle up to the present time. The remaining charge capacity of the vehicle is calculated from the charged electric energy, the charge start time is recalculated, and if the charge start time is later than the current time, the battery is charged until the time arrives. It is characterized by controlling to stop.

  In this way, when charging is proceeding faster than planned due to an increase in power generated by natural energy power generation facilities or a decrease in charging vehicles due to the recovery of the weather, etc., commercial power grid power can be reduced as much as possible by temporarily stopping charging. The power generated by the natural energy power generation facility can be preferentially used without being used.

  In the battery charging system for an electric vehicle according to the present invention, the charging controller periodically calculates the charging capacity necessary for the battery mounted on each electric vehicle being charged, and to the vehicle up to the present time. The remaining charge capacity of the vehicle is calculated from the amount of power charged, the charge start time is recalculated, and if the charge start time is a time before the current time, the battery is charged before the charge completion time. Control is performed so as to increase the charging power for the vehicle.

  In this way, when the charging is delayed from the schedule due to a decrease in the generated power of the natural energy power generation facility due to bad weather or an increase in the number of charging vehicles, the charging is completed by increasing the charging current by the charging completion time. You can give priority to this.

  In the battery charging system for an electric vehicle according to the present invention, the charge controller monitors the presence / absence of connection between the charging connectors and the electric vehicle, and the charging stations and / or the respective charging stations according to fluctuations in the connection state. Controlling to dynamically change the charging current assigned to the charging connector

  In this way, limited charging power can be efficiently used by distributing and redistributing charging currents in units of charging stations / charging connectors according to the connection / charging status of dynamically changing electric vehicles. Can do.

  In the battery charging system for an electric vehicle according to the present invention, the charge controller distributes a charging current value to the electric vehicles connected to the charging connectors on an average.

  In the battery charging system for an electric vehicle according to the present invention, when the electric vehicle is connected to a charging connector that is set in advance to charge with priority, the charging controller has a charging current value for the charging connector. Is preferentially distributed.

  In the battery charging system for an electric vehicle according to the present invention, the charge controller measures a current value charged from each charging connector, and when a difference from a charging current value assigned to each charging connector occurs, The charging current value assigned to each charging connector is corrected.

  In SAE J1772 which is a well-known technology, the charging current value is notified to the electric vehicle by charging the electric vehicle so as not to exceed the notified charging current value. The actual current value is smaller than. That is, although it is a small amount, power is not used. In the case of simultaneous charging of multiple units, a certain amount of power is not used, and the use efficiency of natural energy generated power does not reach 100%. Therefore, by correcting the charging current value in the charge controller, the difference between the generated power and the power used for charging can be eliminated, and the use efficiency of the natural energy generated power can be brought close to 100%.

In the battery charging system for an electric vehicle according to the present invention, the charge controller acquires at least one item of information below and always displays it.
[Item] Power generation amount, charging rate, charging amount, grid power consumption, generated power, charging power, grid power consumption, charging state of each electric vehicle, charging amount of each electric vehicle, natural energy the ratio of the power from different power system from that of the natural energy power generation equipment and power from the power generation equipment.

  In this way, the usage status of natural energy generated power and commercial power grid power is displayed on one screen to visualize information, thereby improving the convenience of operation of the charging control system and improving user awareness. Can do.

As described above, according to the battery charging system for an electric vehicle of the present invention, the generated electric power is received in a natural energy power generation facility such as solar power generation or wind power generation, and the electric power is efficiently transferred to an electric vehicle or the like. It can be used for charging, and effective use of natural energy is achieved.
In addition, by cooperating with the energy management system, it can be expected to reduce electricity charges and reduce CO ₂ .

1 is a schematic configuration diagram illustrating an overall configuration of a charging control system in a charging station of an electric vehicle as an embodiment of a battery charging system for an electric vehicle according to the present invention. It is a flowchart which shows the flow of the basic operation | movement of the charge controller 6 in the charge control system shown in FIG. It is a sequence diagram which shows the flow of the communication process between the apparatuses which comprise the charge control system of this embodiment shown in FIG. It is a figure which shows the result of having simulated the charging condition in the charging station of the electric vehicle which is one Embodiment of the battery charging system for electric vehicles which concerns on this invention.

  Hereinafter, the best mode for carrying out the battery charging system for an electric vehicle of the present invention will be described in detail with reference to the accompanying drawings. 1 to 4 are diagrams illustrating embodiments of the present invention. In these drawings, the same reference numerals denote the same components, and the basic configuration and operation are the same. To do.

  FIG. 1 is a schematic configuration diagram showing an overall configuration of a charging control system in a charging station of an electric vehicle as an embodiment of a battery charging system for an electric vehicle according to the present invention.

  In FIG. 1, as a power supply source in the charge control system of the present embodiment, there are a solar power generation facility 1 and a wind power generation facility 2 that are natural energy power generation facilities, and a commercial power system 3 that is conventionally used. The solar power generation facility 1 and the wind power generation facility 2 are connected to a power conditioner 4. The power conditioner 4 converts the direct current power supplied from the solar power generation facility 1 and the wind power generation facility 2 into alternating current power, and outputs the generated power output value from the solar power generation facility 1 and the wind power generation facility 2. Measure and manage.

The commercial power system 3 and the power conditioner 4 are each connected to a distribution board 5. The distribution board 5 has functions of adjusting the amount of power supplied to each charging station 7 to which it is connected, and functions of interrupting current leakage and limiting current (breaker).
Each charging station 7 receives power from the distribution board 5 and can charge the electric vehicle 9 connected via the charging connector cable and the charging connector 8. One or a plurality of charging connectors 8 are connected to each charging stand 7.

The power conditioner 4 is connected to the charge controller 6 through the communication line 10 between the charge controller and the power conditioner.
The communication line 10 between the charge controller and the power conditioner can use a conventional communication method for connecting a plurality of devices such as wireless communication in addition to serial communication such as the RS485 standard that is frequently used in the industrial field. .

The charge controller 6 is connected to each charge stand 7 via the charge controller-charge stand communication line 11.
For example, a LAN cable (IEEE 802.3 standard) can be used as the communication line 11 between the charge controller and the charging station.

The charge controller 6 periodically obtains the generated power output values from the solar power generation facility 1 and the wind power generation facility 2 measured by the power conditioner 4, and based on this, allocates the supply power at each charging station 7, etc. To decide. The acquisition timing of the generated power output value is appropriately determined according to the change in weather, season, time, operation method, and the like.
In addition, the charge controller 6 performs data communication with each charging station 7 and performs state information acquisition, setting, charging start / stop control, and the like of each charging station 7.

FIG. 2 is a flowchart showing a flow of basic operations of the charge controller 6 in the charge control system of the present embodiment shown in FIG.
In FIG. 2, when the charging control by the charging controller 6 is started, the charging controller 6 first acquires the generated power output value from the power conditioner 4 and calculates the generated current value (step 200).
Subsequently, the number of rechargeable connectors (maximum number) is calculated by dividing the generated current value by the minimum charging current value necessary for charging one electric vehicle (step 201).
The number of charged units is assigned with the total number of connectors 8 connected to vehicles that have not been fully charged at each charging station 7 as an upper limit (step 202).

Based on the number of charging units assigned to each charging station 7, it is determined which of the connectors 8 connected to each charging station 7 is to be charged (step 203).
Subsequently, the lowest current value is assigned to each connector 8 (step 204), and the surplus generated current value is further assigned to each connector 8 (step 205).
The current values assigned to the connectors 8 are added together for each charging station 7 and notified to each charging station 7 (step 206).
The above operation is repeated for each set charging control cycle.

FIG. 3 is a sequence diagram showing a flow of communication processing between devices constituting the charge control system of the present embodiment shown in FIG.
In FIG. 3, first, in the charging start flow, the charge controller transmits a generated power output value request to the power conditioner, and the power conditioner returns the current generated power output value to the charge controller.
Subsequently, the charging controller transmits a charger state confirmation to the charging stand, and the charging stand returns a charging state “charge stop” as a charger state response to the charging controller.
The charge controller calculates a charge current value (assignable value), transmits a charge current value setting to the charging station, and transmits a charge start command.
The charging station notifies the electric vehicle of a charging current value, and the electric vehicle changes the charging current and starts charging. The charging station updates the charging state from “charging stopped” to “charging”.

Next, in the current value change flow, the charge controller transmits a generated power output value request to the power conditioner, and the power conditioner returns the generated power output value to the charge controller. The charging controller transmits a charger state confirmation to the charging stand, and the charging stand returns a charging state “charge stop ” as a charger state response to the charging controller.
The charge controller calculates the charge current value (increase / decrease the allocatable value), sends the charge current value reset to the charge stand, the charge stand notifies the electric vehicle of the charge current value, and the electric vehicle changes the charge current To do.

  Next, in the charge stop flow, the charge controller transmits a generated power output value request to the power conditioner, and the power conditioner returns the generated power output value to the charge controller. Subsequently, the charging controller transmits a charger state confirmation to the charging stand, and the charging stand returns a charging state “charging” to the charging controller as a charger state response. When the charge controller calculates the charge current value and determines that the allocation is not possible, the charge controller transmits a charge current value reset to the charge stand, and the charge stand stops the power supply to the electric vehicle whose charge current value is insufficient. The car stops charging. The charging station updates the state of charge from “charging” to “charging stopped”.

FIG. 4 is a diagram showing a result of simulating a charging situation at a charging station of an electric vehicle which is an embodiment of the battery charging system for an electric vehicle according to the present invention described above.
At 14:59 on January 1, 2013, the charging state measurement value of the electric vehicle at the charging station that has received power from the solar power generation and the commercial power system is displayed.
The display items include the amount of photovoltaic power generation, the charging rate from solar power generation, the total charging amount, the amount of power used from the commercial power grid, the current power generation, the current charging power, and the measurement location of the current grid power usage. ing.
In addition, the flow of charging power from each system is displayed with two types of arrows, and the ratio of the charging amount from each system for each electric vehicle is displayed as a bar graph.

  As mentioned above, although the specific embodiment was shown and demonstrated about the battery charging system for electric vehicles of this invention, this invention is not limited to these. A person skilled in the art can make various changes and improvements to the configuration and function of the battery charging system for electric vehicles in each of the above embodiments without departing from the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Solar power generation equipment 2 Wind power generation equipment 3 Commercial power system 4 Power conditioner 5 Distribution board 6 Charge controller 7 Charging stand 8 Charging connector 9 Electric vehicle 10 Between a charge controller and a power conditioner Communication line 11 Between a charge controller and a charge stand Communication line

Claims (4)

A battery charging system for an electric vehicle that receives electric power from a natural energy power generation facility and charges a battery mounted on a plurality of electric vehicles,
A power conditioner that rectifies and outputs power output from the natural energy power generation facility;
Means for receiving power supply from a power system different from the natural energy power generation facility;
A distribution board that receives power from a power system different from the power output from the power conditioner and the natural energy power generation facility , distributes the power to a plurality of charging stations, and
Has a charging connector one or more electrical vehicle, and receives power from the distribution board, and a plurality of charging stand for transmitting an arbitrary charging current to the each charging connector,
Function of acquiring power generation output value from said power conditioner, the function of determining the respective charging stations and / or the charging current to be allocated to the each charging connector, and the charging current values assigned to each of the electric vehicle wherein through each charging connector A charge controller having a function to notify ,
The charge controller is
The power conditioner in accordance with the change in the generated power output values in conditioner, the function of controlling so as to dynamically change the charging current to be allocated to each charging station and / or the respective charging connector, and
When the actual current value of each electric vehicle is measured through each charging connector, and there is a difference between the actual current value and the charging current value assigned to each charging connector, the actual current value is changed to the assigned charging current value. Function to correct the charging current value assigned to each charging connector so as to approach
The battery charging system for electric vehicles characterized by having . 2. The battery charging system for an electric vehicle according to claim 1, wherein a function of the charging controller notifying a charging current value assigned to each electric vehicle through each charging connector is based on the SAE J1772 standard. . The charge controller monitors the presence or absence of connection between the charge connectors and the electric vehicle,
In accordance with a variation in the connection state, each of the charging station and / or an electric vehicle battery according to claim 1 or 2, characterized in that controls to dynamically change the charging current to be allocated to the each charging connector Charging system. The charge controller, the electric vehicle battery charging system according to any one of claims 1 to 3, characterized in that always displayed to obtain information of at least one item of the following:
Power generation amount of the natural energy power generation facility,
Charging rate,
Charge,
Grid power consumption,
Generated power,
Charging power,
Grid power,
The state of charge of each electric vehicle,
The amount of charge for each electric vehicle,
The proportion of the power from different power system from the electric power and the natural energy power generation equipment from natural energy power generation equipment.