JP2019030049A - Charging device and charging system - Google Patents

Abstract

To appropriately charge a battery even in a case where a communication with a power receiving device is interrupted.SOLUTION: A charging device comprises an acquisition part, a calculation part and a power supply part. The acquisition part acquires battery information including a self-inductance of a coil included in a power receiving device for supplying a current to a battery mounted on a vehicle, and a chargeable capacity indicating a capacity chargeable by the battery. The calculation part calculates a current value to be generated by the coil on the basis of the self-inductance acquired by the acquisition part. The power supply part supplies power to the power receiving device in a non-contact manner on the basis of the current value calculated by the calculation part, and the chargeable capacity.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a charging device and a charging system.

  Conventionally, for example, there is a charging device that charges a battery included in an electric vehicle or a hybrid vehicle in a non-contact manner. In such a charging device, an instruction signal or the like is obtained as needed from a power receiving device that supplies current to the battery via wireless communication, and the current or the like is adjusted based on the instruction signal, and then the battery is connected to the battery via the power receiving device. Charging is performed (see, for example, Patent Document 1).

JP 2012-161145 A

  However, in the conventional charging device, when communication with the power receiving device is interrupted during charging, the instruction signal cannot be obtained, and the battery may not be charged appropriately.

  The present invention has been made in view of the above, and provides a charging device and a charging system that can appropriately charge a battery even when communication with a power receiving device is interrupted. Objective.

  In order to achieve the above-described problem, the charging device according to the embodiment includes an acquisition unit, a calculation unit, and a power feeding unit. The acquisition unit acquires battery information including a self-inductance of a coil included in a power receiving device that supplies current to a battery mounted on the vehicle and a rechargeable capacity indicating a capacity that can be charged by the battery. The calculation unit calculates a current value generated in the coil based on the self-inductance acquired by the acquisition unit. The power supply unit supplies power to the power receiving device in a non-contact manner based on the current value calculated by the calculation unit and the chargeable capacity.

  According to the present invention, it is possible to appropriately charge the battery even when communication with the power receiving apparatus is interrupted.

FIG. 1 is a diagram showing an outline of a charging method. FIG. 2 is a block diagram of the charging system. FIG. 3 is a diagram illustrating an example of a charging pattern. FIG. 4 is a flowchart showing a processing procedure executed by the charging apparatus.

  Hereinafter, a charging device and a charging system according to embodiments will be described in detail with reference to the accompanying drawings. In addition, this invention is not limited by embodiment shown below.

  First, the outline of the charging method according to the embodiment will be described with reference to FIG. FIG. 1 is a diagram showing an outline of a charging method. Such a charging method is performed by the charging device 1 and the power receiving device 50 mounted on the vehicle C.

  The charging method according to the embodiment charges the battery pack 60 that is a battery of the vehicle C in a non-contact manner. As shown in FIG. 1, for example, the charging device 1 is installed so as to be buried in the ground. Then, the charging device 1 generates a current on the power receiving device 50 side by using, for example, electromagnetic induction. The battery pack 60 is charged with the current generated in the power receiving device 50.

  Specifically, in the charging method, a magnetic field is generated between the primary coil and the secondary coil included in the power receiving device 50 by applying a high-frequency current to the primary coil included in the charging device 1. The battery pack 60 is charged with an electromotive force generated by the magnetic field on the secondary coil side.

  Here, in the prior art, charging is performed based on control on the power receiving device side. Specifically, in the prior art, the charging device sequentially obtains an instruction signal for instructing a current value to be passed through the primary coil from the power receiving device, and adjusts the electromotive force generated by the power receiving device based on the instruction signal. It was.

  In addition, since charging is performed by a non-contact method, wireless communication such as WiFi (registered trademark) is adopted for communication between the charging device and the power receiving device. For this reason, communication by wireless communication between the charging device and the power receiving device may be interrupted due to a communication failure or a communication function failure. In such a case, the conventional charging device cannot acquire the instruction signal, and thus cannot properly charge the battery.

  Therefore, in the charging method according to the embodiment, the battery (battery pack 60) is charged even when communication with the power receiving device 50 is interrupted by acquiring battery information from the power receiving device 50 in advance. I was able to do it.

Specifically, in the charging method, for example, battery information is acquired from the power receiving device 50 at the start of charging. Such battery information includes or self-inductance L ₂ of the secondary coil provided in the power receiving device 50, the amount of power until charging is complete (hereinafter, referred to as the chargeable capacity P) a. The chargeable capacity P is “total battery capacity−remaining battery capacity”.

Subsequently, in the charging method, a current value I ₂ generated in the secondary coil is calculated based on the self-inductance L ₂ . That is, in the charging method, it is possible to calculate the power charged to the battery pack 60 based on the self-inductance L _2. It will be described later calculation procedure of such current value I _2. In the charging method, power is supplied based on the current value I ₂ and the chargeable capacity P.

That is, in the charging method according to the embodiment, the current value I ₂ charged in the battery pack 60 is calculated based on the self-inductance L ₂ , and the battery pack 60 is charged by the chargeable capacity P. In other words, in the charging method according to the embodiment, by acquiring the self-inductance L ₂ and the chargeable capacity P, it is possible to charge the battery pack 60 by control of the charging apparatus 1 side.

  Therefore, according to the charging method according to the embodiment, it is possible to appropriately charge the battery even when communication with the power receiving device 50 is interrupted.

  Next, a configuration example of the charging system 100 according to the embodiment will be described with reference to FIG. FIG. 2 is a block diagram of the charging system 100. Charging system 100 includes a charging device 1 and a power receiving device 50. FIG. 2 also shows a battery pack 60 that is a battery.

  First, the power receiving device 50 will be described. The power receiving device 50 includes a secondary coil 51, an instruction unit 52, and a communication unit 53. The communication unit 53 is a communication interface that communicates with the charging device 1. In the charging system 100 according to the embodiment, a wireless communication method such as WiFi can be adopted as a communication method between the charging device 1 and the power receiving device 50. Note that other wireless communication methods such as infrared communication may be applied as the wireless communication method.

  The secondary coil 51 generates a magnetic field with the primary coil 15 included in the charging device 1 by electromagnetic induction, and generates a current corresponding to the magnetic field. By supplying this current to the battery pack 60, the battery pack 60 is charged.

The secondary coil 51 is provided with a current sensor and a voltage sensor (not shown), and an actual current value I ₂ and a voltage value V ₂ flowing through the secondary coil 51 are output to the instruction unit 52 as needed.

  The battery pack 60 is, for example, a secondary battery such as a lithium ion secondary battery or a nickel hydride secondary battery, and charges the electric power generated by the secondary coil 51. The electric power charged in the battery pack 60 is used to drive a motor (not shown) that drives the vehicle C.

  In addition, the battery pack 60 includes a remaining capacity sensor that measures the remaining battery capacity, a temperature sensor that measures the temperature inside the battery pack 60, and the like. Output to the instruction unit 52 every second).

The instruction unit 52 generates an instruction signal at a predetermined cycle and transmits the instruction signal to the charging device 1 via the communication unit 53 every time it is generated. Such an instruction signal indicates, for example, a current value I ₂ generated by the secondary coil 51.

Specifically, the instruction unit 52 generates an instruction signal for instructing an optimal current value I ₂ or the like at a predetermined period based on the measured value and the chargeable capacity P, and transmits the instruction signal to the charging device 1 every time it is generated. . In other words, the instruction unit 52 optimizes the current value I ₂ generated by the secondary coil 51 according to the chargeable capacity P, the temperature in the battery pack 60, and the like. Thereby, it becomes possible to shorten the time for charging the battery pack 60 and to suppress the deterioration of the battery pack 60 due to charging. Note that the instruction signal may indicate a current value I ₁ applied to the primary coil 15 by a power feeding unit 24 described later. In such a case, for example, the instruction unit 52 can calculate the current value I ₁ by acquiring the self-inductance L ₁ of the primary coil 15 included in the charging device 1.

The instruction unit 52 outputs a start request to the charging device 1 when the communication unit 53 is connected to the charging device 1. The start request includes, for example, information indicating the current value I ₁ applied to the primary coil 15 at the start of charging, the frequency of the alternating current, and the like. The charging device 1 starts to supply power to the power receiving device 50 based on the start request.

In the charging system 100 according to the embodiment, the instruction unit 52 outputs battery information including the self-inductance L ₂ of the secondary coil 51 and the chargeable capacity P of the battery pack 60 to the charging device 1.

  Here, the instruction unit 52 outputs the battery information together with the above-described start request, but the battery information may be always output. Further, the instruction unit 52 may transmit the battery information only when the communication strength with the charging device 1 starts to decrease, that is, when communication interruption is likely to occur.

  Furthermore, the instruction unit 52 can also output performance information indicating the performance of the battery pack 60 to the charging device 1 as battery information. Such performance information is information including the type and model of the battery pack 60, for example. A specific example of processing on the charging device 1 side based on the performance information will be described later with reference to FIG.

  The charging device 1 includes a control unit 2, a storage unit 3, a communication unit 10, and a primary coil 15. The communication unit 10 is a communication interface that communicates with the communication unit 53 of the power receiving device 50. An alternating current having a current value I 1 generated by the control unit 2 is applied to the primary coil 15. Thereby, a magnetic field is generated between the primary coil 15 and the secondary coil 51, and the battery pack 60 can be charged.

Further, the primary coil 15 is provided with a current sensor that measures a current value I ₁ flowing through the primary coil 15 and a voltage sensor (none of which is shown) that measures a voltage value V ₁ of the primary coil 15. . The current value I ₁ and voltage value V ₁ measured by the current sensor and voltage sensor are output to the calculation unit 22 of the control unit 2.

  The control unit 2 includes an acquisition unit 21, a calculation unit 22, a selection unit 23, and a power feeding unit 24. The control unit 2 includes, for example, a computer having a central processing unit (CPU), a read only memory (ROM), a random access memory (RAM), a hard disk drive (HDD), an input / output port, and various circuits.

  The CPU of the computer functions as the acquisition unit 21, the calculation unit 22, the selection unit 23, and the power supply unit 24 of the control unit 2 by reading and executing a program stored in the ROM, for example.

  In addition, at least one or all of the acquisition unit 21, the calculation unit 22, the selection unit 23, and the power supply unit 24 of the control unit 2 are configured by hardware such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array). It can also be configured.

  The storage unit 3 corresponds to, for example, a RAM or an HDD. The RAM and HDD can store charging pattern information 31 and information on various programs. Note that the charging device 1 may acquire the above-described program and various types of information via another computer or a portable recording medium connected via a wired or wireless network.

The acquisition unit 21 acquires the battery information described above from the power receiving device 50 via the communication unit 10. Further, the acquisition unit 21, among the acquired battery information, and outputs the self-inductance L ₂ and the chargeable capacity P to calculator 22 via the power supply unit 24, and outputs the performance information to the selector 23.

  The acquisition unit 21 acquires an instruction signal and outputs the instruction signal to the power feeding unit 24. And when the acquisition part 21 cannot acquire said instruction | indication signal from the power receiving apparatus 50, ie, when communication with the charging device 1 and the power receiving apparatus 50 stops, communication was interrupted instead of the instruction signal. An interruption signal indicating this is output to the power supply unit 24. As a result, the power supply unit 24 switches from the control based on the instruction signal to the control based on the calculation unit 22.

The calculation unit 22 calculates a current value I ₂ generated in the secondary coil 51 of the power receiving device 50 based on the battery information input from the acquisition unit 21. In other words, the calculating unit 22 calculates the current value I ₂ which is charged to the battery pack 60. The calculation unit 22 can also calculate the charging time T based on the current value I ₂ and the chargeable capacity P.

Here, when the current value I ₁ flowing through the primary coil 15, the voltage value V ₁ , and the self-inductance L ₁ of the primary coil 15, the current value I ₂ generated in the secondary coil 51 is expressed by the following equation (1): It becomes the relationship.

Here, "M" is the mutual inductance of the primary coil 15 and secondary coil 51, with the primary coil 15 from the self-inductance _{L 2} of the self-inductance _{L 1} and the secondary coil 51 the following formula (2) Can be calculated.

“K” is a coupling constant and indicates the degree of coupling between the primary coil 15 and the secondary coil 51. Here, the coupling constant k is an arbitrary constant from “0” to “1”. The self-inductance L ₁ , the voltage value V ₁ and the current value I ₁ are known values. The calculation unit 22 can calculate the current value I ₂ using the above equations (1) and (2).

The calculation unit 22, based on the current value I ₂ and the chargeable capacity P, the following equation (3), calculates the charging time T.

When the acquisition unit 21 acquires the above interruption signal, the calculation unit 22 calculates the charging time T by the above equation (3) based on the chargeable capacity P immediately before the interruption. In this case, the calculating unit 22 may be to calculate the charging time T based on the current value I ₂ for interrupted immediately before, it calculates the charging time T based on other current value I ₂ which is separately calculated It may be.

Then, the calculation unit 22 instructs the power feeding unit 24 to flow the current value I ₁ corresponding to the current value I ₂ through the primary coil 15 for the charging time T. Thereby, even if communication interruption with the power receiving apparatus 50 occurs, the power receiving apparatus 50 can be appropriately charged.

  In such a case, the calculation unit 22 can also set the actual power feeding time shorter than the charging time T. Thereby, overcharge of the battery pack 60 can be prevented reliably. The calculation unit 22 may set the actual power supply time longer than the calculated charging time T. In such a case, the battery pack 60 can be fully charged by allowing the overcharged power to escape from the battery pack 60 on the power receiving device 50 side.

Further, the calculating unit 22, for example, by constantly calculating the current value I _2, may be possible to calculate the latest chargeable capacity P. For example, the calculation unit 22 calculates the latest chargeable capacity P by subtracting the integrated value of the current value I ₂ from the chargeable capacity P.

Then, the calculation unit 22 can determine the current value I ₁ applied to the primary coil 15 so that the latest chargeable capacity P is “0”, that is, the battery pack 60 is not overcharged. That is, by the calculating unit 22 by calculating the latest chargeable capacity P, it is possible to make the current value I ₁ in the variable.

  The selection unit 23 selects a charge pattern from the charge pattern information 31 stored in the storage unit 3 based on the performance information input from the acquisition unit 21. Here, the charge pattern information 31 will be described with reference to FIG. FIG. 3 is a diagram illustrating an example of a charging pattern. The charge pattern information 31 is information relating to a charge pattern optimized according to the performance of each battery pack 60, for example.

As shown in FIG. 3, for example, the charge pattern information 31 is information in which the optimal value of the current value I _{2 that} is optimal for charging the performance of the battery pack 60 and each chargeable capacity P is associated. In other words, the charge pattern information 31 is information in which the instruction signal is databased for each battery pack 60. Hereinafter, the current value I2 described in the charge pattern information 31 is referred to as an ideal current value I.

When there is a charging pattern that matches the performance information from the charging pattern information 31, the selection unit 23 selects the charging pattern. The calculation unit 22, based on the charge pattern selected by the selection unit 23, for example, setting the current value I ₁ is applied to the primary coil 15 corresponding to the ideal current value I for each chargeable capacity P. The calculation unit 22, such current value I ₁ can be calculated based on the equations (1) and (2) below.

  As described above, in the charging device 1, charging is performed in accordance with the performance of the battery pack 60 even when communication with the power receiving device 50 is interrupted by supplying power based on the charging pattern. Can do. Thereby, deterioration of the battery pack 60 due to charging can be prevented.

For example, the charging pattern information 31 may be information stored in advance by the developer of the charging apparatus 1 or may be information created on the charging apparatus 1 side based on the past charging history. Good. Specifically, the charging device 1 learns the charging pattern by recording the current value I ₂ and the chargeable capacity P indicated by the instruction signal in the storage unit 3 for each battery pack 60, for example. You can also.

  In such a case, for example, the deterioration information (for example, the total number of times of charging) indicating the degree of deterioration of the battery pack 60 is acquired from the power receiving apparatus 50, and the deterioration information is learned together with the charging pattern. Charging can be performed appropriately according to the degree of deterioration. In addition, the charge pattern shown in FIG. 3 is an example, and is not limited to this.

Returning to the description of FIG. 2, the power feeding unit 24 will be described. The power supply unit 24 supplies power to the power receiving device 50 in a non-contact manner based on the current value I ₂ calculated by the calculation unit 22 and the chargeable capacity P. Specifically, the power supply unit 24 includes an oscillation circuit and an amplifier circuit when communication is interrupted, generates a current value I ₁ instructed by the calculation unit 22, and supplies the current of the current value I ₁ to the primary coil 15. Apply to.

As described above, in the charging device 1, when communication with the power receiving device 50 is interrupted, by applying the current value I ₁ calculated by the calculation unit 22 to the primary coil 15, the communication is interrupted. Even if it exists, it becomes possible to charge with respect to a battery (battery pack 60) appropriately.

In addition, when the communication with the power receiving device 50 is normal, the power supply unit 24 generates a current having a current value I ₁ indicated by the instruction signal transmitted from the power receiving device 50 and applies the current to the primary coil 15. To do. That is, when the communication between the charging device 1 and the power receiving device 50 is normal, the power feeding unit 24 charges the battery pack 60 based on the instruction signal. As a result, the processing by the calculation unit 22 and the like can be omitted, and the load on the control unit 2 can be suppressed.

  Next, the process procedure which the charging device 1 which concerns on embodiment performs using FIG. 4 is demonstrated. FIG. 4 is a flowchart showing a processing procedure executed by the charging apparatus 1. Note that the processing procedure shown below is executed by the control unit 2.

As shown in the figure, first, the acquisition unit 21 acquires battery information (step S101). Subsequently, the calculation unit 22 calculates a current value I ₂ based on the self-inductance L ₂ included in the battery information (Step S102).

Subsequently, the acquisition unit 21 determines whether or not the communication state with the power receiving device 50 is normal (step S103). In the determination, when the communication state is not normal (step S103, No), i.e., if the communication is interrupted, the calculating unit 22 calculates the charging time T based on the charging capacity P and the current value I ₂ (Step S104). The power supply unit 24 supplies power based on the current value _{I 2} and the charging time T (step S105), and ends the process.

  On the other hand, when the communication state is normal (step S103, Yes), the power supply unit 24 supplies power based on the instruction signal from the power receiving device 50 (step S106), and ends the process.

As described above, the charging device 1 according to the embodiment includes the acquisition unit 21, the calculation unit 22, and the power feeding unit 24. Acquisition unit 21 acquires the battery information including the charge capacity P showing the self-inductance L ₂ and the chargeable capacity of the coil provided in the power receiving device 50 for supplying a current to the battery mounted on the vehicle C (the battery pack 60) To do. The calculation unit 22 calculates a current value I ₂ generated in the coil based on the self-inductance L ₂ acquired by the acquisition unit 21. The power supply unit 24 supplies power to the power receiving device 50 in a non-contact manner based on the current value I2 calculated by the calculation unit 22 and the chargeable capacity P. Therefore, according to the charging device 1 which concerns on embodiment, even if it is a case where communication with the power receiving apparatus 50 stops, it can charge with respect to a battery appropriately.

  By the way, although embodiment mentioned above demonstrated the case where the charging device 1 supplies electric power based on battery information, when communication interruption with the charging device 1 and the power receiving apparatus 50 arises, it is not limited to this. Absent. That is, the charging device 1 may acquire battery information before starting charging and supply power to the power receiving device 50 based only on the battery information.

  In addition, for example, when the communication state is restored after communication with the power receiving device 50 is interrupted, the charging device 1 can also supply power to the power receiving device 50 based on the instruction signal.

Further, the charging device 1 may acquire the current value I ₂ actually measured by the power receiving device 50 after starting the power feeding. In such a case, the charging apparatus 1 can correct the current value I ₂ which is calculated on the basis of the self-inductance L ₂ on the basis of the current value I _2. Thus, it is possible to improve the accuracy of calculating the current value I _2, it is possible to charge the power receiving device 50 more appropriately.

  In the above-described embodiment, the case where the charging device 1 and the power receiving device 50 transmit and receive data via wireless communication has been described. However, wired communication via a cable or the like may be used. In such a case, even when the charging device 1 becomes unable to communicate with the power receiving device 50 due to a cable disconnection or the like, it is possible to appropriately supply power to the power receiving device 50.

  In the above-described embodiment, the case where the power receiving device 50 and the battery pack 60 are mounted on the vehicle C has been described. However, the power receiving device 50 and the battery pack 60 are mounted on an electronic device such as a personal computer or a mobile phone. Also good.

  Further effects and modifications can be easily derived by those skilled in the art. Thus, the broader aspects of the present invention are not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications can be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.

1 charging apparatus 15 primary coil 21 acquisition unit 22 calculation unit 23 selector 24 feed unit 31 charging pattern information 50 receiving device 51 a secondary coil 52 instructing section 60 battery pack C vehicle I _{1, I 2} current values V _{1, V 2} Voltage value L ₁ , L ₂ Self-inductance

Claims (5)

An acquisition unit that acquires battery information including a self-inductance of a coil included in a power receiving device that supplies current to a battery mounted on a vehicle and a chargeable capacity that indicates a chargeable capacity of the battery;
A calculation unit that calculates a current value generated in the coil based on the self-inductance acquired by the acquisition unit;
A charging device comprising: a power supply unit that supplies power to the power receiving device in a non-contact manner based on the current value calculated by the calculation unit and the chargeable capacity. The calculation unit includes:
The charging device according to claim 1, wherein a charging time required for charging is calculated based on the current value and the chargeable capacity, and a power feeding time is determined based on the charging time. The power feeding unit is
The charging device according to claim 1, wherein when the communication between the acquisition unit and the power receiving device is interrupted, power is supplied to the power receiving device based on the current value and the chargeable capacity. The battery information is
Including performance information indicating the performance of the battery;
A storage unit that stores a charging pattern according to the performance of each battery;
A selection unit that selects the charging pattern stored in the storage unit based on the performance information acquired by the acquisition unit;
The power feeding unit is
4. The charging device according to claim 1, wherein when the charging pattern selected by the selection unit is selected, power is supplied based on the charging pattern. The charging device according to any one of claims 1 to 4,
A charging system comprising: the power receiving device.

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