JP5440158B2 - Battery charging method and charging system - Google Patents

Description

  The present invention relates to a battery charging method and a charging system.

  Recently, power consumers such as individual houses, apartment houses, large stores, factories, etc. have their own charging equipment and power generation equipment to cover the supply and demand of power without using commercial power as much as possible. To be increased. Since there is a limit to the power supply and demand of only individual power consumers, as described in Patent Document 1, a power network is formed between a plurality of power consumers, and surplus power of a certain power consumer It is disclosed that power is supplied as a shortage of electricity consumers. A system that has a generator and a power storage device and that can supply and receive power as much as possible through self-sustaining operation is called a microgrid (or microgrid system). In this microgrid, Self-sustained operation that minimizes power transfer in the country is strongly desired.

  Also, recently, vehicles such as electric vehicles and plug-in hybrid vehicles that drive a traveling motor using a battery as a power source (vehicles equipped with a traveling battery) are increasing. Patent Document 2 discloses that power is exchanged between electric vehicles. In the device described in Patent Document 2, charging is performed from a vehicle that requires discharge to a vehicle that desires charging, and charging / discharging is left to the user's intention.

WO2004 / 073136 A1 JP 2007-252118 A

  By the way, when the vehicle is parked for a long time and the state where the vehicle-mounted battery is not charged continues for a long time, the charged amount is reduced by natural discharge. In addition, when charging an in-vehicle battery, it may be desired that external power cannot be supplied or it is desired to be as independent of external power as possible. Is a problem.

  The present invention has been made in view of the circumstances as described above, and its purpose is to use a charge / discharge between a plurality of vehicles to prevent a situation in which the amount of power stored in the in-vehicle battery becomes extremely small. It is an object of the present invention to provide a battery charging method and a charging system which can be prevented.

In order to achieve the above object, the following solution is adopted in the battery charging method of the present invention. That is, as described in claim 1 in the claims,
A battery charging method for charging an in-vehicle battery of a plurality of parked vehicles,
A first step of connecting a plurality of in-vehicle batteries to a power network and an information communication network in a parking lot;
A second step of acquiring the storage amount of the plurality of in-vehicle batteries via the information communication network;
A third step for identifying a vehicle battery that can be discharged and a vehicle battery to be charged based on the amount of electricity stored in the second step;
A fourth step of charging the in-vehicle battery to be charged by discharging in a dischargeable range from the dischargeable in-vehicle battery identified in the third step;
It is supposed to be equipped with.

  According to the above solution, even when external power cannot be obtained or when it is not desired to rely on external power as much as possible, the power of the in-vehicle battery from a vehicle with a large amount of power storage is used, and another vehicle with a small amount of power storage is used. It is possible to charge the in-vehicle battery, which is preferable in leveling the storage amount for all vehicles by preventing the storage amount of some in-vehicle batteries from becoming extremely small. In particular, in the case of a usage form of a vehicle where leveling of the storage amount is desired or does not cause a problem, for example, a rental car, a car shelling vehicle, a vehicle exhibited in a vehicle (especially used car) sales company, a vehicle in an airport parking lot It is preferable for a vehicle being transported by train or ship, a vehicle of a condominium resident, and the like.

A preferred mode based on the above solution is as described in claims 2 to 6 in the claims. That is,
In the third step, the in-vehicle batteries that can be discharged are ranked according to the amount of stored electricity,
In the fourth step, discharging for charging is performed in order of descending power storage amount of the on-vehicle battery that can be discharged.
(Corresponding to claim 2). In this case, it becomes even more preferable for leveling the amount of electricity stored in all the vehicles (the in-vehicle battery).

A fifth step of determining a degree of deterioration of the plurality of in-vehicle batteries from information obtained via the information communication network;
In the third step, as the vehicle battery that can be discharged, the vehicle battery with a low degree of deterioration is ranked high as long as the stored amount of electricity is the same.
(Corresponding to claim 3). In this case, it is preferable for protecting a vehicle-mounted battery having a high degree of deterioration.

A fifth step of determining a degree of deterioration of the plurality of in-vehicle batteries from information obtained via the information communication network;
In the third step, the in-vehicle battery having a high degree of deterioration is excluded as the dischargeable in-vehicle battery.
(Corresponding to claim 4). In this case, an in-vehicle battery having a high degree of deterioration can be reliably protected.

The power network is configured in a microgrid including a power storage device, a power generation device, and a power consumption load and connected to a commercial power source,
In the fourth step, when only the discharge power from the dischargeable on-vehicle battery is insufficient as the charge power to the on-vehicle battery to be charged, the insufficient charge power is first provided by discharging from the power storage device. If the charging power is still insufficient, it will be covered by power procurement from the commercial power source.
(Corresponding to claim 5). In this case, the in-vehicle battery can be charged by effectively using the power grid of the microgrid. In addition, while improving the opportunity for autonomous operation of the microgrid, it is possible to reliably charge an in-vehicle battery with a small amount of charge by using power from a commercial power source as needed.

In the third step, the in-vehicle batteries to be charged are ranked based on the amount of stored electricity,
In the fourth step, charging is performed in the order of decreasing storage amount as the in-vehicle battery to be charged,
(Corresponding to claim 6). In this case, it becomes even more preferable for leveling the amount of electricity stored in all the vehicles (the in-vehicle battery).

In order to achieve the above object, the following solution is adopted in the charging system according to the present invention. That is, as described in claim 7 in the claims,
A battery charging system for charging an in-vehicle battery of a plurality of parked vehicles,
A power network and an information communication network that are installed in a parking lot and connected to a plurality of in-vehicle batteries,
A storage amount acquisition means for acquiring a storage amount of the plurality of in-vehicle batteries via the information communication network;
Based on the storage amount obtained by the storage amount acquisition means, identification means for identifying a vehicle battery that can be discharged and a vehicle battery to be charged;
Charge execution means for charging the in-vehicle battery to be charged by discharging in a dischargeable range from the dischargeable in-vehicle battery identified by the identification means;
It is supposed to be equipped with. According to the said solution technique, the charging system which can acquire the effect corresponding to Claim 1 is provided.

A preferred mode based on the above solution is as set forth in claim 8 in the claims. That is,
The identifying means ranks the in-vehicle batteries that can be discharged according to the storage amount, and the charge execution means causes discharging for charging in descending order of the storage amount among the in-vehicle batteries that can be discharged.
This is done (corresponding to claim 8). In this case, the effect corresponding to claim 2 can be obtained.

  ADVANTAGE OF THE INVENTION According to this invention, while using the charging / discharging between several vehicles, while being able to prevent the situation where the electrical storage amount of a vehicle-mounted battery becomes extremely small, the electrical storage amount of all the vehicle-mounted batteries is equalized. Preferred above.

The figure which shows an example of a microgrid. The figure which shows another example of a microgrid. The flowchart which shows the example of control of this invention. The flowchart which shows another example of control of this invention. The figure which shows the example which identifies the vehicle-mounted battery which can be discharged according to an electrical storage amount, and the vehicle-mounted battery of a charge required. The figure which shows the example which identifies the vehicle-mounted battery which cannot be discharged, and the vehicle-mounted battery which can be discharged according to a deterioration degree. The figure which shows the example which identifies the vehicle-mounted battery of a discharge required according to the elapsed time in a full charge state. The figure which shows the example which identifies the vehicle-mounted battery which cannot be discharged according to the time until the next use.

  FIG. 1 shows an example of a microgrid MG. In the figure, reference numeral 1 denotes a commercial power source which is owned and managed by an electric power company and is a normal AC power source. A microgrid MG is connected to the commercial power source 1. The microgrid MG is composed of a large number of detached houses, a condominium type where a large number of houses are occupying, and an appropriate facility such as a factory or a sales office, or an aggregate thereof. You can also.

  The microgrid MG includes a common power generation device G including a solar power generator, a common power storage device (a common storage battery, for example, a large-capacity battery) B, and a charging facility capable of simultaneously charging a plurality of traveling battery-equipped vehicles EV ( C) also used for discharging from the vehicle EV. As the common power generation device G, in addition to the solar power generator, an appropriate type of power generation device using fuel such as wind power generation or cogeneration can be used. Of course, the microgrid MG is connected to an electric load that consumes power (for example, an air conditioner, a lighting device, a cooking utensil, etc.). The microgrid MG is connected to the commercial power source 1 through the gateway E, and frequency adjustment, voltage adjustment, and phase adjustment are performed when power is exchanged with the commercial power source. The charging facility C has a large number of connection outlets so that several tens of vehicles EV can be charged and discharged simultaneously.

  The microgrid MG is provided with a management device U configured using a computer. As will be described later, the management device U controls the charging facility C to control charging / discharging among a large number of vehicles EV.

  FIG. 2 shows another example of a microgrid. The microgrid MG has one common power network 10 and a plurality of individual power networks 20. A common power generation device G and a common power storage device B are connected to the common power network 10, and the common power network 10 is connected to the commercial power source 1 via the gateway E.

  The individual power network 20 is connected to the common power network 10 via HEMS (having a function corresponding to gateway E). The individual power network 20 includes an individual power generation device G2 and an individual power storage device B2, and a part of the individual power network 20 includes a charging facility for a traveling battery-equipped vehicle EV that the individual power network 20 has. In FIG. 2, for some of the individual power grids 20, only HEMS is shown, and the individual power generation equipment G <b> 2 and the individual power storage equipment B <b> 2 are omitted.

  As one of the individual power networks 20, a vehicle-dedicated power network 21 (corresponding to the charging facility C) for charging and discharging the traveling battery-equipped vehicle EV is provided. The vehicular power grid 21 is also connected to the common power grid 10 via the HEMS, and includes an individual power generation device G2 and an individual power storage device B2. And the management apparatus U2 similar to the management apparatus U of FIG. 1 is provided. The vehicle power grid 21 has a large number of connection outlets to which a large number of in-vehicle batteries are connected so that a large number of vehicles can be charged and discharged simultaneously.

  1 and 2, a power line for charging / discharging connected to the vehicle EV is provided with a communication line for forming an information communication network, and the vehicle EV (particularly, its in-vehicle battery) and the management device U. Or information transmission is performed between U2. The information communication network can also be configured by a wireless system.

  Next, a charge / discharge control example performed by the management device U (U2) will be described with reference to the flowchart shown in FIG. In the following description, S indicates a step. First, in S1, the state of each in-vehicle battery in the plurality of vehicles EV connected to the charging facility C is read (reading via the information communication network). The battery information is information indicating the degree of deterioration of the in-vehicle battery in addition to the amount of power storage (for example, battery temperature, amount of decrease in power storage amount per hour, internal resistance value, etc.). Next, in S2, the use state (past use history) of the in-vehicle battery is read via the information communication network. This information is information indicating the degree of deterioration of the in-vehicle battery. The amount of discharge, the total distance traveled after battery replacement, and the elapsed time in a fully charged state.

  After S2, in S3, as will be described later, a dischargeable vehicle-mounted battery is extracted from the plurality of vehicle-mounted batteries, and the total dischargeable amount is calculated. Thereafter, in S4, the in-vehicle batteries that are determined to be dischargeable are ranked in descending order of the charged amount. At the time of this ranking, if the amount of stored electricity is the same, an in-vehicle battery with a small degree of deterioration is ranked high.

  After S4, in S5, the on-vehicle battery that requires charging is extracted, and the total amount of charge is calculated. Thereafter, in S6, it is determined whether or not a subtraction value obtained by subtracting the total charge amount calculated in S5 from the total dischargeable amount calculated in S3 is 0 or more. When the determination in S6 is YES, the battery can be charged only by discharging from the in-vehicle battery. At this time, the in-vehicle batteries that discharge the charging power are selected in the order of the ranks ranked in S4 (some of the in-vehicle batteries that can be discharged may be selected or some in-vehicle batteries may be selected. May be selected only). Thereafter, in S8, the dischargeable in-vehicle battery selected in S7 is discharged, and the charging required battery extracted in S5 is charged with this discharge power.

  When the determination in S6 is NO, the charging power cannot be provided only by the discharging power from the dischargeable battery. At this time, in S9, all the in-vehicle batteries that can be discharged extracted in S3 are selected. Next, in S10, the battery that is required to be charged is charged while discharging from all the selectable on-vehicle batteries that are selected and supplying the insufficient charging power from other power of the microgrid MG. In the case of FIG. 1, supplementation of the insufficient charging power from the microgrid MG is first performed by discharging from the common power storage device B, and if it is still insufficient, power is procured from the commercial power source 1. In the case of FIG. 2, the charging power for the shortage is first provided by discharging from the individual power storage device B2, and if it is still insufficient, it is provided by discharging from the common power storage device B2, and if it is still insufficient, commercial power is supplied. It is covered by power procurement from Source 1.

  FIG. 4 is a flowchart showing an example of control when a discharge required battery is included. In other words, the battery tends to deteriorate early after a long period of time with the battery fully charged (including almost fully charged, for example, 95% or more in the charged amount). Is preferably positively discharged for battery protection, and FIG. 4 shows a control example for that purpose.

  Since FIG. 4 corresponds to FIG. 3, description of overlapping parts will be omitted or simplified, and description will be made by paying attention to unique parts in FIG. 4. First, S21 to S26 in FIG. 4 correspond to S1 to S6 in FIG. Of these, S21 and S22 are the same as S1 and S2. In S23, the fully charged in-vehicle battery is extracted, and the extraction of the dischargeable battery is extracted by excluding the fully charged in-vehicle battery. Further, as the ranking in S24, the fully charged vehicle-mounted battery is ranked as the highest ranking (positioned so that the discharging ranking is the highest). S25 is the same as S5. In S26, “required charge amount” from “required discharge amount (dischargeable amount from in-vehicle battery in full charge state) + dischargeable amount (removable amount from dischargeable battery excluding in-vehicle battery in full charge state)”. It is determined whether or not the subtracted value obtained by subtracting 0 is 0 or more.

  When the determination in S26 is YES, the charging power can be secured only with the discharging power from the in-vehicle battery. At this time, the processes of S27 and S28 are performed (corresponding to S7 and S8). When selecting the discharge battery in S27, a fully charged vehicle-mounted battery is first selected (because it is positioned in the highest order). After S28, in S29, it is determined whether or not the value obtained by subtracting “required charge amount” from “required discharge amount” is 0 or more. The determination in S29 is a determination as to whether or not a fully charged vehicle-mounted battery remains. When the determination in S29 is YES, in S30, discharging from the fully charged vehicle-mounted battery is executed. The electric power discharged in S30 can be used for charging other in-vehicle batteries having a small amount of power storage, but can also be discharged to power storage devices of the microgrid MG. Specifically, in the case of FIG. 1, first, the common power storage device B is discharged, and if the discharge is still insufficient, the commercial power source 1 is discharged. In the case of FIG. 2, the battery is first discharged to the individual power storage device B2, and if it is insufficiently discharged, it is discharged to the common power storage device B. If the discharge is still insufficient, the commercial power source 1 is discharged. Is done. In this way, the in-vehicle battery in the fully charged state is forcibly discharged, and the protection is achieved.

  When the determination in S26 is NO, in S31, in addition to selecting all the dischargeable batteries, a discharge required battery is selected. Thereafter, in addition to discharging from the in-vehicle battery selected in S31, electric power that is insufficient for charging is supplied from the outside (from other than the in-vehicle battery) in the same manner as in S10.

  Next, an example of a technique for extracting (identifying) an in-vehicle battery that can be discharged and an in-vehicle battery that requires charging will be described with reference to FIG. First, in FIG. 5, an in-vehicle battery whose current charged amount is equal to or greater than a first predetermined value (for example, 80%) is identified as a dischargeable battery. And the in-vehicle battery with a larger amount of stored electricity is ranked higher in discharging order. In the case of the control example of FIG. 4, the fully-charged on-board battery is first excluded and a dischargeable battery is extracted, and the fully-charged on-board battery is positioned at the highest rank when ranking the discharge. The total dischargeable amount is obtained by subtracting the first predetermined value from the current charged amount for each dischargeable battery and adding the subtracted values.

  In addition, an in-vehicle battery whose current storage amount is equal to or less than a second predetermined value (for example, 30%) set as a value smaller than the first predetermined value is extracted as a rechargeable battery. And the vehicle-mounted battery with a smaller amount of stored electricity is positioned as a vehicle-mounted battery with higher order of charge required. The total charge amount is obtained by subtracting the current charged amount from the second predetermined value for each battery requiring charging, and adding up the subtracted values.

  In the example of FIG. 5, the in-vehicle batteries are identified by A, B, C,..., But the in-vehicle batteries A and D are extracted as the batteries that can be discharged because the charged amount is larger than the first predetermined value. . Further, it is extracted that the in-vehicle battery B is a battery that needs to be charged so that the amount of stored power is equal to or less than the second predetermined value. And since the amount of stored electricity is between the first predetermined value and the second predetermined value, the in-vehicle battery C becomes an in-vehicle battery that is neither discharged nor charged.

  FIG. 6 shows an example in which the degree of deterioration of the in-vehicle battery is determined by looking at the rate of change of the internal resistance value from the new state. That is, an in-vehicle battery whose internal resistance value change rate is larger than the third predetermined value is an undischargeable battery, and an in-vehicle battery whose internal resistance value change rate is the fourth predetermined value or less is extracted as a dischargeable battery. In addition, an in-vehicle battery having a smaller change rate of the internal resistance value is considered to be an in-vehicle battery having a higher discharge order. In the case of FIG. 6, the in-vehicle batteries A and C are extracted as being dischargeable batteries. Moreover, it extracts that the vehicle-mounted battery B is a dischargeable battery. The in-vehicle battery D is a battery that does not discharge or charge.

  In FIG. 7, an in-vehicle battery whose elapsed time in the fully charged state is a fifth predetermined value (for example, 3 hours) or more is determined to be a fully charged battery having the highest discharging order. In the case of FIG. 7, since the elapsed time when the in-vehicle battery A is in the fully charged state is equal to or longer than the fifth predetermined value, the battery is required to be charged with the highest discharge order. Moreover, about the vehicle-mounted battery B, C, and D, since the elapsed time in a full charge state is less than the 5th predetermined value, it is not made into a discharge required battery (it may be made into a dischargeable battery). In addition, if it is a full charge, it can also be set as a discharge required battery irrespective of the elapsed time in a full charge state.

  FIG. 8 shows an example in which a non-dischargeable battery is identified based on the time until the vehicle EV is next used (predicted time). That is, when the time until the next use (predicted time) is equal to or less than a sixth predetermined value (for example, 3 hours), it is determined that the vehicle battery cannot be discharged (discharge prohibited). In addition, a vehicle-mounted battery having a shorter time until next use is considered to be a battery having a higher charge priority.

Here, as described in S <b> 1 and S <b> 2 of FIG. 3, an example will be described in which various kinds of information indicating the current state of the in-vehicle battery and its past use state are comprehensively determined to determine the discharge order. First, the discharge order value Y _n of each battery is obtained for each battery based on the following equation (1). In the formula, the suffix “n” indicates the distinction between in-vehicle batteries. Α1, α2, α3... Are weighting coefficients. Further, x1 _n , x2 _n , x3 _n ... Are discharge orders ranked for each of the various information (for example, ranking for each information as shown in FIGS. 5 to 8).

Y _n = α 1 · x 1 _n + α 2 · x 2 _n + α 3 · x 3 _n + (1)

A vehicle battery with a smaller Y _n is a vehicle battery with a higher discharge order. Of course, in the calculation of the discharge order, only the battery determined to be a dischargeable battery is considered, and the in-vehicle battery in which the elapsed time in the fully charged state is long and the discharge battery is required, or the in-vehicle battery that is not allowed to be discharged. The battery is not a target, and the in-vehicle battery that is determined to be a discharge battery is positioned in a higher order than the discharge order based on the above calculation formula. The charging ranking can also be performed in the same manner as the discharging ranking (using a charging ranking calculation formula corresponding to formula (1)).

  Although the embodiment has been described above, the present invention is not limited to the embodiment, and can be appropriately changed within the scope described in the scope of claims. For example, the invention includes the following cases. . The microgrid MG can be of an appropriate type. For example, the microgrid MG may not include the individual generator G2 and the individual power storage device B2 in the example of FIG. The charging equipment for the traveling battery-equipped vehicle EV may be connected to a common power grid, connected to an individual power grid, or connected to both power grids.

The traveling battery-equipped vehicle EV is not limited to one held in the microgrid, and may be another vehicle unrelated to the microgrid. The facility where the charging facility C is provided is not limited to the microgrid, and may be various facilities where a plurality of vehicles may be parked simultaneously.

  The present invention can level the amount of electricity stored in a plurality of in-vehicle batteries.

MG: Microgrid EV: Vehicle with vehicle for running U: Management device G: Common power generator G2: Individual power generator B: Common power storage device B2: Individual power storage device C: Charging equipment 1: Commercial power source

Claims (8)

A battery charging method for charging an in-vehicle battery of a plurality of parked vehicles,
A first step of connecting a plurality of in-vehicle batteries to a power network and an information communication network in a parking lot;
A second step of acquiring the storage amount of the plurality of in-vehicle batteries via the information communication network;
A third step for identifying a vehicle battery that can be discharged and a vehicle battery to be charged based on the amount of electricity stored in the second step;
A fourth step of charging the in-vehicle battery to be charged by discharging in a dischargeable range from the dischargeable in-vehicle battery identified in the third step;
A battery charging method comprising: In claim 1,
In the third step, the in-vehicle batteries that can be discharged are ranked according to the amount of stored electricity,
In the fourth step, discharging for charging is performed in order of descending power storage amount of the on-vehicle battery that can be discharged.
A method for charging a battery. In claim 2,
A fifth step of determining a degree of deterioration of the plurality of in-vehicle batteries from information obtained via the information communication network;
In the third step, as the vehicle battery that can be discharged, the vehicle battery with a low degree of deterioration is ranked high as long as the stored amount of electricity is the same.
A method for charging a battery. In claim 1 or claim 2,
A fifth step of determining a degree of deterioration of the plurality of in-vehicle batteries from information obtained via the information communication network;
In the third step, the in-vehicle battery having a high degree of deterioration is excluded as the dischargeable in-vehicle battery.
A method for charging a battery. In any one of Claims 1 thru | or 4,
The power network is configured in a microgrid including a power storage device, a power generation device, and a power consumption load and connected to a commercial power source,
In the fourth step, when only the discharge power from the dischargeable on-vehicle battery is insufficient as the charge power to the on-vehicle battery to be charged, the insufficient charge power is first provided by discharging from the power storage device. If the charging power is still insufficient, it will be covered by power procurement from the commercial power source.
A method for charging a battery. In any one of Claims 1 thru | or 5,
In the third step, the in-vehicle batteries to be charged are ranked based on the amount of stored electricity,
In the fourth step, charging is performed in the order of decreasing storage amount as the in-vehicle battery to be charged,
A method for charging a battery. A battery charging system for charging an in-vehicle battery of a plurality of parked vehicles,
A power network and an information communication network that are installed in a parking lot and connected to a plurality of in-vehicle batteries,
A storage amount acquisition means for acquiring a storage amount of the plurality of in-vehicle batteries via the information communication network;
Based on the storage amount obtained by the storage amount acquisition means, identification means for identifying a vehicle battery that can be discharged and a vehicle battery to be charged;
Charge execution means for charging the in-vehicle battery to be charged by discharging in a dischargeable range from the dischargeable in-vehicle battery identified by the identification means;
A battery charging system comprising: In claim 7,
The identifying means ranks the in-vehicle batteries that can be discharged according to the storage amount, and the charge execution means causes discharging for charging in descending order of the storage amount among the in-vehicle batteries that can be discharged.
A battery charging system.

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