JP2016082772A - Charger, power storage device and current control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress a charging time from increasing while suppressing generation of a temperature rise in an internal component of a charger.SOLUTION: An electric current output from a charger 1 to a power storage device 8 is controlled according to a current command value transmitted from the power storage device 8 to the charger 1. When a temperature T of an internal component of the charger 1 is not less than a threshold value Tdown, an outputtable current value of the charger 1 is decreased to decrease a current command value, which is then transmitted from the charger 1 to the power storage device 8. When the temperature T is not more than a threshold value Treturn smaller than a threshold value Tdown, an outputtable current value of the charger 1 is increased to increase the current command value, which is then transmitted from the charger 1 to the power storage device 8.SELECTED DRAWING: Figure 1

Description

  The present invention relates to control of current output from a charger to a power storage device.

  The cooling performance of the charger may deteriorate due to clogging of a filter provided in the intake hole of the charger. When the cooling performance of the charger is lowered, the temperature of the internal components of the charger may be overheated and the charger may be damaged.

  As a countermeasure, when the temperature of the internal parts of the charger exceeds the threshold, the current output from the charger to the power storage device is reduced to suppress the heat generation of the internal parts and the temperature of the internal parts becomes overtemperature. It is conceivable to suppress this.

  In addition, if the current input to the battery decreases before the capacity of the battery included in the power storage device reaches the desired capacity, the time required for the battery capacity to reach the desired capacity increases. For this reason, during charging of the battery, it is desired not to make the current output from the charger to the power storage device too small even when the temperature of the internal components of the charger increases.

  As a related technique, there is a technique for controlling the current output from the charger to the power storage device according to the temperature of the internal components of the charger. For example, see Patent Documents 1 to 3.

Patent No. 5474326 Japanese Patent Laid-Open No. 11-122839 Japanese Patent No. 4653219

  An object of this invention is to suppress the increase in charging time, suppressing the temperature rise of the internal component of a charger.

The charger of the present embodiment includes a temperature detection unit and a control unit.
A temperature detection part detects the temperature of the internal component of a charger.
The control unit controls the current output to the power storage device according to the current command value transmitted from the power storage device, and reduces the current command value when the temperature of the internal component is equal to or higher than the first threshold. The outputable current value is lowered and transmitted to the power storage device, and when the temperature of the internal component is equal to or lower than the second threshold value which is smaller than the first threshold value, the outputable current value of the charger is increased to increase the current command value. Send to.

  Thereby, when the temperature of the internal components of the charger becomes equal to or higher than the first threshold value, the current output from the charger to the power storage device is reduced, so that the temperature increase of the internal components of the charger can be suppressed. In addition, when the temperature of the internal parts of the charger is equal to or lower than the second threshold value that is smaller than the first threshold value, the current output from the charger to the power storage device increases, so that an increase in charging time can be suppressed.

  ADVANTAGE OF THE INVENTION According to this invention, the increase in charging time can be suppressed, suppressing the temperature rise of the internal component of a charger.

It is a figure which shows an example of the charger of embodiment. It is a flowchart which shows an example of operation | movement of the control part of the electrical storage apparatus in 1st Embodiment. It is a flowchart which shows an example of operation | movement of the control part of the charger in 1st Embodiment. It is a figure which shows an example of the change of the output current of a charger, and the temperature of an internal component. It is a figure which shows the other example of the change of the output current of a charger, and the temperature of an internal component. It is a flowchart which shows an example of operation | movement of the control part of the electrical storage apparatus in 2nd Embodiment. It is a flowchart which shows an example of operation | movement of the control part of the charger in 2nd Embodiment.

<First Embodiment>
FIG. 1 is a diagram illustrating an example of the charger according to the first embodiment.
A charger 1 shown in FIG. 1 includes a temperature detection unit 2, a power supply unit 3, a storage unit 4, and a control unit 5.

The temperature detection part 2 is comprised by the thermistor, for example, and detects the temperature T of the internal component of the charger 1. FIG.
The power supply unit 3 is constituted by, for example, an AC / DC converter, and converts AC power supplied from an external power supply 6 provided outside the charger 1 into DC power.

  The storage unit 4 is constituted by, for example, a RAM (Random Access Memory) or a ROM (Read Only Memory), and stores a threshold value Tstop, a threshold value Tdown, a threshold value Treturn, and the like, which will be described later.

  Control unit 5 receives data indicating a current command value transmitted from power storage device 8 mounted on vehicle 7 (such as an electric vehicle or a hybrid vehicle). In addition, the control unit 5 controls the operation of the power supply unit 3 so that the current output from the charger 1 to the power storage device 8 increases as the current command value increases, and when the current command value decreases, the charger The operation of the power supply unit 3 is controlled so that the current output from 1 to the power storage device 8 is reduced. In addition, control unit 5 transmits data indicating the outputable current value of power supply unit 3 to power storage device 8. The control unit 5 includes, for example, a CPU (Central Processing Unit), a multi-core CPU, or a programmable device (FPGA (Field Programmable Gate Array), PLD (Programmable Logic Device, etc.)).

The power storage device 8 includes a battery 9, a power supply unit 10, and a control unit 11.
The battery 9 is composed of, for example, a secondary battery such as a lithium ion battery or a nickel metal hydride battery, or a capacitor, and supplies power to a traveling motor or an electrical device mounted on the vehicle 7.

The power supply unit 10 is configured by, for example, a DC / DC converter, and charges the battery 9 using electric power supplied from the charger 1.
The control unit 11 controls the operation of the power supply unit 10. Further, the control unit 11 receives data indicating the output possible current value transmitted from the charger 1. Further, the control unit 11 obtains a current command value based on the voltage of the battery 9, SOC (State Of Charge), etc., with the outputable current value as an upper limit value. Further, the control unit 11 transmits data indicating the current command value to the control unit 5 of the charger 1. The control unit 11 is configured by, for example, a CPU, a multi-core CPU, or a programmable device.

  FIG. 2 is a flowchart illustrating an example of the operation of the control unit 11 of the power storage device 8 in the first embodiment. In addition, the operation | movement shown in FIG. 2 shall be repeatedly performed for every fixed period, for example.

  First, when the control unit 11 determines that the SOC of the battery 9 is smaller than the desired SOC (S21: No), the control unit 11 obtains a current command value based on the voltage of the battery 9, the SOC, and the like (S22). For example, the control unit 11 sets a predetermined value as a current command value during a period from the start of charging until the voltage of the battery 9 reaches a predetermined voltage. This charging period is hereinafter referred to as a CC charging period. Further, the control unit 11 gradually decreases the current command value while keeping the voltage of the battery 9 substantially constant during the period from when the voltage of the battery 9 reaches a predetermined voltage until the SOC of the battery 9 becomes a desired SOC. Go. Hereinafter, this charging period is referred to as a CV charging period.

  Next, the control unit 11 determines that the difference between the obtained current command value and the actual current input to the power storage device 8 is smaller than a predetermined value (S23: No), and the obtained current command value is received. If it is determined that the current value is smaller than the outputtable current value (S24: Yes), the obtained current command value is transmitted to the charger 1 (S25).

  Further, when determining that the received output possible current value is smaller than the obtained current command value (S24: No), the control unit 11 transmits the output possible current value as a current command value to the charger 1 (S26). ). Thereby, the current command value can be set with the outputable current value transmitted from charger 1 to power storage device 8 as the upper limit value. That is, when the output possible current value transmitted from the charger 1 decreases, the power storage device 8 decreases the current command value and transmits it to the charger 1. When the output possible current value transmitted from the charger 1 increases, The current command value is increased and transmitted to the charger 1.

  If control unit 11 determines that the difference between the obtained current command value and the actual current input to power storage device 8 is greater than or equal to a predetermined value (S23: Yes), it executes error processing (S27). For example, after notifying the user that an error has occurred as error processing, the control unit 11 transmits a charging end instruction to the charger 1, stops the power supply unit 10, and ends the charging process of the battery 9. Note that the control unit 11 executes S22 and S23 again before executing the error processing, and again determines that the difference between the obtained current command value and the actual current input to the power storage device 8 is equal to or greater than a predetermined value. In such a case, error processing may be executed.

  When the control unit 11 determines that the SOC of the battery 9 is equal to or higher than the desired SOC (S21: Yes), the control unit 11 transmits a charge end instruction to the charger 1 and stops the power supply unit 10 to perform the charging process of the battery 9. The process ends (S28).

  FIG. 3 is a flowchart illustrating an example of the operation of the control unit 5 of the charger 1 according to the first embodiment. In addition, the output possible current value of the power supply part 3 set at the time of the start of the charging process of the battery 9 shall be set to a value higher than the current command value determined in advance during the CC charging period.

  First, when the charging process of the battery 9 is started, the control unit 5 stands by until a current command value or a charge end instruction is received (S31: No, S32: No), and when a current command value is received (S31: Yes). Then, the operation of the power supply unit 3 is controlled so that a current corresponding to the current command value is output from the charger 1 (S33). For example, the control unit 5 controls the operation of the power supply unit 3 so that substantially the same current as a constant current command value is output from the charger 1 during the CC charging period, and the current command value decreases during the CV charging period. Accordingly, the operation of the power supply unit 3 is controlled so that the output current of the charger 1 also decreases.

  Next, the control unit 5 acquires the temperature T detected by the temperature detection unit 2 (S34), and determines that the temperature T is equal to or higher than the threshold Tstop (S35: Yes), stops the power supply unit 3 and stops the battery 9 The charging process is terminated (S36). For example, the threshold value Tstop is set to a value slightly smaller than the temperature of the internal component when there is a possibility that the charger 1 may break down due to the temperature rise of the internal component of the charger 1. Thereby, it is possible to reduce the failure of the charger 1 due to the temperature rise of the internal components of the charger 1.

  Further, the control unit 5 determines that the temperature T is lower than the threshold value Tstop (S35: No), and determines that the temperature T is equal to or higher than the threshold value Tdown (first threshold value) (S37: Yes), the current power supply unit 3 is reduced (S38), the resettable output possible current value is transmitted to the power storage device 8 (S39), and then it waits until the next current command value or charging end instruction is received (S31: No, S32: No). Note that threshold value Tstop> threshold value Tdown. For example, when the control unit 5 determines that the temperature T is equal to or higher than the threshold value Tdown, the current power supply unit 3 is set so that the current current command value becomes the current command value when the temperature of the internal components of the charger 1 decreases. Lower the output possible current value.

  Further, when the control unit 5 determines that the temperature T is lower than the threshold value Tdown (S37: No) and determines that the temperature T is equal to or lower than the threshold value (second threshold value) (S40: Yes), the current power supply unit 3 is increased (S41), and the resettable output possible current value is transmitted to the power storage device 8 (S39), and then waits until the next current command value or charging end instruction is received (S31: No, S32: No). Note that threshold value Tstop> threshold value Tdown> threshold value Treturn. For example, when the control unit 5 determines that the temperature T is equal to or lower than the threshold value Treturn, the control unit 5 increases the current outputtable current value of the power supply unit 3 to the outputable current value set at the start of the charging process.

  Further, when the control unit 5 determines that the temperature T is lower than the threshold value Tdown (S37: No) and determines that the temperature T is higher than the threshold value Treturn (S40: No), the currently settable output possible current value (S31: No, S32: No).

Moreover, if the control part 5 receives charge completion instruction | indication (S31: No, S32: Yes), the power supply part 3 will be stopped and the charge process of the battery 9 will be complete | finished (S36).
For example, FIG. 4 is a diagram illustrating an example of changes in the output current of the charger 1 and the temperature T of the internal components.

  As shown in FIG. 4, in the CC charging period and the CV charging period, when the temperature T does not exceed the threshold value Tdown, the constant is transmitted from the power storage device 8 to the charger 1 during the period from the start of charging to the end of the CC charging period. The output current of the charger 1 becomes constant based on the current command value. Further, the output current of the charger 1 gradually decreases based on the current command value that gradually decreases during the period from the start of the CV charging period to the end of charging.

FIG. 5 is a diagram illustrating another example of changes in the output current of the charger 1 and the temperature T of the internal components.
As shown in FIG. 5, in the CC charging period and the CV charging period, when the temperature T is repeatedly greater than or equal to the threshold value Tdown or less than or equal to the threshold value Treturn, the period (temperature) until the temperature T becomes equal to or greater than the threshold value Tdown The output current of the power supply unit 3 during the falling period) is smaller than the output current of the power supply unit 3 during the period (temperature rising period) until the temperature T becomes equal to or lower than the threshold value Treturn and then becomes equal to or higher than the threshold value Tdown. This is because the outputable current value of the power supply unit 3 is lowered during the temperature decrease period, and the outputable current value of the power supply unit 3 is returned to the original value during the temperature increase period. Therefore, in the example shown in FIG. 5, the temperature T gradually increases during the temperature decrease period, and the temperature T gradually decreases during the temperature increase period. As a result, the temperature T can be prevented from exceeding the threshold value Tstop, so that the temperature of the internal components of the charger 1 can be prevented from becoming overtemperature, and the failure of the charger 1 due to the temperature rise of the internal components. Can be prevented. In addition, since the output current of the charger 1 during the temperature rise period can be made larger than the output current of the charger 1 during the temperature fall period, the increase of the charge period required until the capacity of the battery 9 reaches the desired capacity is increased. Can be suppressed.

  As described above, in the charger 1 of the first embodiment, when the temperature T of the internal components of the charger 1 is equal to or higher than the threshold value Tdown, the current output from the charger 1 to the power storage device 8 becomes small. Temperature rise can be suppressed. In addition, when the temperature T of the internal components of the charger 1 is equal to or lower than the second threshold value which is smaller than the first threshold value, the current output from the charger 1 to the power storage device 8 increases, so that an increase in charging time can be suppressed. it can.

  In S37 of FIG. 3, the output possible current value is further lowered by one or more steps when the temperature T is continuously equal to or higher than the threshold value Tdown even though the output possible current value has already been reduced. May be.

Second Embodiment
FIG. 6 is a flowchart illustrating an example of the operation of the control unit 11 of the power storage device 8 according to the second embodiment. In the first embodiment, the charger 1 controls the current output to the power storage device 8 according to the current command value transmitted from the power storage device 8 in order to lower the temperature. However, in the second embodiment, the charger 1 Controls the current output to the power storage device 8 by itself regardless of the current command value. However, in the first embodiment, since the power storage device 8 performs error processing when the difference between the current command value and the actual current input to the power storage device 8 increases, in the second embodiment, the charger When 1 controls the current output to the power storage device 8 to lower the temperature, the power storage device 8 is notified so that no error processing is performed in the power storage device 8. The configurations of the charger 1 and the power storage device 8 in the second embodiment are the same as the configurations of the charger 1 and the power storage device 8 in the first embodiment. Also, the operation shown in FIG. 6 is repeatedly performed at regular intervals.

First, when it is determined that the SOC of the battery 9 is smaller than the desired SOC (S61: No), the control unit 11 obtains a current command value based on the voltage of the battery 9, the SOC, and the like (S62).
Next, the control unit 11 determines that the temperature protection flag transmitted from the charger 1 indicating that the temperature protection period has been entered has not been received (S63: No), and the obtained current command value and the power storage device When it is determined that the difference from the actual current input to 8 is smaller than the predetermined value (S64: No), the obtained current command value is transmitted to the charger 1 (S65). As shown in FIG. 5, the temperature protection period is a period for controlling (lowering) the output possible current value of the power supply unit 3 according to the temperature T of the internal components of the charger 1.

  If control unit 11 determines that the temperature protection flag has been received (S63: Yes), whether or not the difference between the obtained current command value and the actual current input to power storage device 8 is greater than or equal to a predetermined value. Without performing such determination processing, the obtained current command value is transmitted to the charger 1 (S65). As a result, the current output from the charger 1 to the power storage device 8 in order to lower the temperature T of the internal components of the charger 1 temporarily decreases, so that the current command value and the actual current input to the power storage device 8 It is possible to prevent erroneous determination that an error has occurred when the difference between the two values exceeds a predetermined value.

  Control unit 11 determines that the temperature protection flag has not been received (S63: No), and determines that the difference between the obtained current command value and the actual current input to power storage device 8 is greater than or equal to a predetermined value. Then (S64: Yes), error processing is executed (S66). For example, after notifying the user that an error has occurred as error processing, the control unit 11 transmits a charging end instruction to the charger 1, stops the power supply unit 10, and ends the charging process of the battery 9. Note that the control unit 11 executes S64 again before executing the error processing, and again determines that the difference between the obtained current command value and the actual current input to the power storage device 8 is equal to or greater than a predetermined value. The error processing may be executed.

  When the control unit 11 determines that the SOC of the battery 9 is equal to or higher than the desired SOC (S61: Yes), the control unit 11 transmits a charge end instruction to the charger 1 and stops the power supply unit 10 to perform the charging process of the battery 9. The process ends (S67).

  FIG. 7 is a flowchart illustrating an example of the operation of the control unit 5 of the charger 1 according to the second embodiment. In addition, the output possible current value of the power supply part 3 set at the time of the start of a charging process shall be set to the value higher than the electric current command value determined beforehand in CC charge period.

  First, when the charging process of the battery 9 is started, the control unit 5 stands by until a current command value or a charge end instruction is received (S71: No, S72: No), and when a current command value is received (S71: Yes). Then, the temperature T of the internal component detected by the temperature detection unit 2 is acquired (S73).

Next, when the control unit 5 determines that the temperature T is equal to or higher than the threshold Tstop (S74: Yes), the control unit 5 stops the power supply unit 3 and ends the charging process of the battery 9 (S75).
Further, the controller 5 determines that the temperature T is lower than the threshold value Tstop (S74: No), and determines that the temperature T is equal to or higher than the threshold value Tdown (first threshold value) (S76: Yes). The operation of the power supply unit 3 is controlled so as to reduce the output current (S77), a temperature protection flag indicating that the temperature protection period has been entered is transmitted to the power storage device 8 (S78), and the next current command value or charging end instruction is transmitted. (S71: No, S72: No). Note that threshold value Tstop> threshold value Tdown. For example, when the control unit 5 determines that the temperature T is equal to or higher than the threshold value Tdown, the current output current of the charger 1 becomes the current when the temperature of the internal components of the charger 1 is lowered. Reduce output current. Note that the order of S77 and S78 may be reversed.

  Further, the control unit 5 determines that the temperature T is lower than the threshold value Tdown (S76: No), determines that the output current of the charger 1 has already been reduced (S79: Yes), and the temperature T is equal to the threshold value Treturn ( If it is determined that it is larger than the second threshold value (S80: No), S77 and S78 are executed.

  Control unit 5 determines that the output current of charger 1 has already been reduced (S79: Yes), and determines that temperature T is equal to or lower than threshold value Treturn (S80: Yes), it outputs to power storage device 8. The operation of the power supply unit 3 is controlled so that the current rises to a current corresponding to the current command value (S81), and waits until the next current command value or a charge end instruction is received (S71: No, S72: No). .

  Further, when the control unit 5 determines that the temperature T is lower than the threshold value Tdown (S76: No) and determines that the output current of the charger 1 has not yet been reduced (S79: No), the control unit 5 determines the current command value to be received. The operation of the power supply unit 3 is controlled so that a corresponding current is output from the charger 1 (S81), and the operation waits until a next current command value or a charge end instruction is received (S71: No, S72: No). .

Moreover, if the control part 5 receives the charge completion instruction | indication (S71: No, S72: Yes), the power supply part 3 will be stopped and the charge process of the battery 9 will be complete | finished (S75).
Thus, the charger 1 of the second embodiment reduces the output current of the charger 1 regardless of the current command value when the temperature T of the internal components of the charger 1 is equal to or higher than the threshold value Tdown. Temperature rise of internal parts can be suppressed. Further, when the temperature of the internal component becomes equal to or lower than the threshold Treturn smaller than the threshold Tdown, the current output to the power storage device 8 is increased to a current corresponding to the current command value, and therefore the temperature T becomes equal to or higher than the threshold Tdown and the output of the charger 1 Even if the current becomes smaller than the current command value, the current can be increased again, and an increase in charging time can be suppressed.

DESCRIPTION OF SYMBOLS 1 Charger 2 Temperature detection part 3 Power supply part 4 Storage part 5 Control part 6 External power supply 7 Vehicle 8 Power storage device 9 Battery 10 Power supply part 11 Control part

Claims (7)

A temperature detector for detecting the temperature of the internal parts of the charger;
The output of the charger is used to control the current output to the power storage device according to the current command value transmitted from the power storage device, and to decrease the current command value when the temperature of the internal component is equal to or higher than the first threshold value. A possible current value is lowered and transmitted to the power storage device. When the temperature of the internal component is equal to or lower than a second threshold value that is smaller than the first threshold value, the output possible current value of the charger is set to increase the current command value. A control unit for raising and transmitting to the power storage device;
A charger comprising: The charger according to claim 2,
When the outputable current value transmitted from the charger decreases, the power storage device decreases the current command value and transmits it to the charger, and when the outputable current value transmitted from the charger increases, A charger characterized by increasing a current command value and transmitting it to the charger. A power storage device that transmits a current command value to a charger and receives a current output from the charger,
When the output possible current value of the charger decreases, the current command value is reduced and transmitted to the charger.When the output possible current value increases, the current command value is increased and transmitted to the charger.
The output possible current value of the charger decreases when the temperature of the internal components of the charger is equal to or higher than a first threshold, and increases when the temperature of the internal components is equal to or lower than a second threshold smaller than the first threshold. A power storage device characterized by the above. In a charger that outputs current to a power storage device, a current control method for controlling a current output to the power storage device according to a current command value transmitted from the power storage device,
Detecting the temperature of the internal parts of the charger,
When the temperature of the internal component is equal to or higher than a first threshold value, the outputable current value of the charger is decreased and transmitted to the power storage device to decrease the current command value, and the temperature of the internal component is lower than the first threshold value. When the value is less than or equal to the second threshold value, the current control value is increased and the outputable current value of the charger is increased and transmitted to the power storage device. A charger that outputs a current to the power storage device according to a current command value transmitted from the power storage device,
When the temperature of the internal components of the charger is equal to or higher than the first threshold, the current output to the power storage device is reduced regardless of the current command value, and the current command value and the actual current input to the power storage device are In order to prevent the determination process whether or not the difference is greater than or equal to a predetermined value in the power storage device, the fact that the temperature protection period has been entered is transmitted to the power storage device,
When the temperature of the internal component is equal to or lower than a second threshold value that is smaller than the first threshold value, the current output to the power storage device is increased to a current corresponding to the current command value. The charger according to claim 5, wherein
The power storage device
When receiving that it is in the temperature protection period, without performing a determination process whether or not the difference between the current command value and the actual current input to the power storage device is a predetermined value or more,
The charger performs the determination process when it has not received that the temperature protection period has been entered. In a charger that outputs a current to the power storage device according to a current command value transmitted from the power storage device, a current control method for controlling a current output to the power storage device,
When the temperature of the internal components of the charger is equal to or higher than a first threshold, the current output to the power storage device is reduced regardless of the current command value, and the current command value and the actual current input to the power storage device are In order to prevent the determination process whether or not the difference is greater than or equal to a predetermined value in the power storage device, the fact that the temperature protection period has been entered is transmitted to the power storage device,
When the temperature of the internal component is equal to or lower than a second threshold value smaller than the first threshold value, the current output to the power storage device is increased to a current corresponding to the current command value.

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