JP2011188544A - Control unit of battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control unit of a battery utilizing the battery efficiently and extend the service life of the battery. <P>SOLUTION: The control unit 16 of a battery controls a residual capacity of the battery mounted on a vehicle to an actual use region between an upper-limit capacity and a lower-limit capacity. The control unit 16 includes a detection unit 42 for detecting at least one of a location of the vehicle, a season, and a date, a capacity setting unit 43 for setting the upper-limit capacity and the lower-limit capacity based on a result detected by the detection unit, and a charge detection unit 41 for detecting whether the battery is under charge. The capacity setting unit sets the upper-limit capacity and the lower-limit capacity so that width of the actual use region is nearly fixed when the charge detection unit detects that the battery is under charge. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a battery control device.

  Conventionally, an electric vehicle using a motor as a drive source is known. In an electric vehicle using this type of motor as a drive source, the motor is generally driven by the electric power stored in the battery. Therefore, when the electric power of the battery is exhausted, the motor cannot be driven. You will not be able to run on your own. Therefore, it is necessary to always store electric power in the battery.

  Here, the battery mounted on the electric vehicle is used in an extremely severe environment. In particular, a battery that drives a motor for running an electric vehicle needs to supply power continuously in response to an output request from a user (driver) even in a high temperature environment. Therefore, the battery becomes high temperature due to heat generated by self-discharge in addition to the environmental temperature. This accelerates the deterioration of the battery and further increases the probability of thermal runaway.

  Therefore, in Patent Document 1, in order to prevent the battery from becoming an abnormally high temperature, the remaining capacity (SOC) of the battery is charged / discharged while being controlled to an actual use region between the upper limit capacity and the lower limit capacity, In addition, a control method is disclosed in which charging and discharging is performed by lowering the upper limit capacity when the ambient temperature or the battery temperature is high.

JP 2001-161004 A

  In an electric vehicle that does not have charging means while traveling, the charging energy is mainly an external power source such as a charging stand provided outside the vehicle. Therefore, charging and running are performed in different time zones and environmental conditions.

  However, when the upper limit capacity and the lower limit capacity of the battery are set according to the temperature closest to the electric vehicle measured at the time of charging and discharging as in Patent Document 1, there is a possibility that a desired battery capacity and output cannot be obtained during traveling. .

Specifically, desired battery capacity and output cannot be obtained when the electric vehicle is traveling in the following cases.
First, when an electric vehicle is stopped in a warm daytime and is going to start running at night when the temperature is lowered, the lower limit capacity is increased during the running, which may result in insufficient battery capacity and insufficient output.
Subsequently, when charging of the battery is terminated at night and the vehicle starts running the next morning when it suddenly cools down, there is a risk that the battery capacity shortage and output shortage may occur because the lower limit capacity has increased during running.
In addition, when driving from a flat area to a place with a low temperature such as a high altitude, the lower limit capacity increases due to a decrease in the battery temperature as the outside air temperature changes, resulting in insufficient battery capacity and insufficient output. There is a fear.

  In addition, when the battery is used outside the actual use region (between the upper limit capacity and the lower limit capacity), there are problems that the output becomes insufficient and the battery life is shortened.

  Therefore, the present invention has been made in view of the above circumstances, and provides a battery control device that can efficiently use a battery and improve the life of the battery.

  In order to solve the above-described problem, the invention described in claim 1 is configured such that a remaining capacity of a battery (for example, the battery 15 in the embodiment) mounted on a vehicle (for example, the electric vehicle 10 in the embodiment) is set to an upper limit capacity. (E.g., upper limit capacity SOC in the embodiment) and a battery control device (e.g., ECU 16 in the embodiment) that controls the actual use region between the lower limit capacity (e.g., the lower limit capacity SOC in the embodiment) and A detection unit (for example, the detection unit 42 in the embodiment) that detects at least one of the location, season, and date, and a capacity that sets the upper limit capacity and the lower limit capacity based on the detection result of the detection unit A setting unit (for example, the capacity setting unit 43 in the embodiment) and a charge detection unit (for example, detecting whether the battery is being charged) Charge detection unit 41) in the embodiment, and when the capacity detection unit detects that the battery is being charged in the charge detection unit, the width of the actual use area is substantially constant The upper limit capacity and the lower limit capacity are set.

  The invention described in claim 2 is a location map storing the upper limit capacity and the lower limit capacity corresponding to the location, a season map storing the upper limit capacity and the lower limit capacity corresponding to the season, and the date. And a storage unit (for example, storage unit 44 in the embodiment) that stores at least one of the upper limit capacity and the date map in which the lower limit capacity is stored, and the capacity setting unit includes: Based on the detection result of the detection unit, the upper limit capacity and the lower limit capacity are extracted from the storage unit and set.

  The invention described in claim 3 is a location map storing the upper limit capacity and the lower limit capacity corresponding to the location, a season map storing the upper limit capacity and the lower limit capacity corresponding to the season, and the date. Further comprising an external communication means (for example, the GPS unit 30 in the embodiment) capable of acquiring at least one of the upper limit capacity and the date map in which the lower limit capacity is stored. The upper limit capacity and the lower limit capacity are extracted from the acquired map and set based on the detection result of the detection unit.

  The invention described in claim 4 further includes a travel range setting unit (for example, a travel range setting unit 45 in the embodiment) that sets a travel range of the vehicle from the location of the vehicle and the capacity of the battery. The unit extracts the lowest temperature point having the lowest temperature information from the points included in the set travel range, and sets the upper limit capacity and the lower limit capacity based on the extraction result. Yes.

  The invention described in claim 5 further includes a battery state detection unit (for example, a battery state detection unit 46 in the embodiment) that detects a deterioration state of the battery, and the capacity setting unit detects the battery state detection unit. The upper limit capacity and the lower limit capacity are corrected based on the result.

  According to the first aspect of the present invention, the battery can secure a predetermined actual use area under any environment. Therefore, the battery can be used efficiently and the life of the battery can be improved.

  According to the second aspect of the present invention, since the upper limit capacity and the lower limit capacity of the battery are only extracted from the map stored in advance, the setting process of the upper limit capacity and the lower limit capacity can be performed quickly.

  According to the third aspect of the present invention, necessary information can be easily and appropriately acquired by the external communication means. Moreover, the latest data can be acquired more reliably and easily by acquiring various maps by an external communication means.

  According to the invention described in claim 4, when the vehicle is stopped in a low temperature environment, the battery temperature gradually approaches the lowest temperature as time passes. Even if fluctuates, the battery can be charged efficiently.

  According to the invention described in claim 5, since the upper limit capacity and the lower limit capacity of the battery can be set more appropriately, the battery can be used more efficiently and the life of the battery can be improved. it can.

It is a schematic block diagram of the electric vehicle in embodiment of this invention. It is a block diagram which shows the equipment connected to ECU in embodiment of this invention. It is a block diagram which shows the structure of ECU in embodiment of this invention. It is a flowchart which shows the charge control method of the battery of the electric vehicle in embodiment of this invention. It is a temperature-lower limit capacity | capacitance SOC map in embodiment of this invention. It is a lower limit capacity | capacitance SOC-upper limit capacity | capacitance SOC map in embodiment of this invention. It is a graph which shows the daily minimum temperature according to the month from 1989 to 2009 in A point in the embodiment of the present invention. It is a table | surface (1) which shows the setting result of the upper limit capacity | capacitance SOC in embodiment of this invention. It is a figure which shows the positional relationship of the present value of an electric vehicle, traveling range, and B point and C point in embodiment of this invention. It is a graph which shows the daily minimum temperature according to the month from 1989 to 2009 in the B point and the C point in the embodiment of the present invention. It is a table | surface (2) which shows the setting result of the upper limit capacity | capacitance SOC in embodiment of this invention.

  Next, an embodiment of the present invention will be described with reference to FIGS. In the present embodiment, an electric vehicle will be described as an electric vehicle.

  FIG. 1 is a schematic configuration diagram of an electric vehicle. As shown in FIG. 1, the electric vehicle 10 includes a drive motor 12, a gear box (G / B) 13 connected to the drive motor 12, and left and right provided via a drive shaft connected to the gear box 13. Are supplied from an external power source (not shown), a battery 15 disposed on the bottom surface of the vehicle body 11 to supply electric power to the drive motor 12, an ECU 16 that controls the running of the electric vehicle 10, and the like. And a charging connector 17 for receiving the generated electric power.

  The drive motor 12 is composed of, for example, a DC brushless motor, and is connected to a PCU (current control unit) 21 that controls the drive and power generation of the drive motor 12. Further, the PCU 21 is connected to a battery 15 that exchanges power with the drive motor 12. Examples of the power include supply power supplied to the drive motor 12 during driving and output power output from the drive motor 12 during power generation by regenerative operation.

  The PCU 21 receives a control command from the ECU (control device) 16 and controls driving of the drive motor 12 and power generation. For example, when the drive motor 12 is driven, the drive motor 12 is driven and controlled by converting DC power output from the battery 15 into PWM output based on a torque command output from the ECU 16. On the other hand, when the drive motor 12 generates power, the AC power output from the drive motor 12 is converted into DC power, and the battery 15 is charged.

  FIG. 2 is a block diagram showing devices connected to the ECU 16. As shown in FIG. 2, a battery 15 and a PCU 21 are connected to the ECU 16, and a drive motor 12 and a resolver 29 that detects the rotation speed of the drive motor 12 are connected via the PCU 21. The ECU 16 is connected to a GPS unit 30 that detects the position of the electric vehicle 10 so that the current position of the electric vehicle 10 can be received.

  FIG. 3 is a block diagram showing the configuration of the ECU 16. As shown in FIG. 3, the ECU 16 includes a charge detection unit 41 that detects whether or not the battery 15 is being charged, a detection unit 42 that detects the location and date of the electric vehicle 10, and a detection result of the detection unit 42. Based on the capacity setting unit 43 for setting the upper limit capacity SOC and the lower limit capacity SOC of the battery 15, the location map storing the upper limit capacity SOC and the lower limit capacity SOC corresponding to the location of the electric vehicle 10, the upper limit capacity SOC corresponding to the season The storage unit 44 stores a seasonal map in which the lower limit capacity SOC is stored, a date map in which the upper limit capacity SOC and the lower limit capacity SOC corresponding to the date are stored, and the location of the electric vehicle 10 and the capacity of the battery 15 A travel range setting unit 45 that sets the travel range of the automobile 10 and a battery that detects the deterioration state of the battery 15 A state detection unit 46, and a.

  The area between the lower limit capacity SOC and the upper limit capacity SOC of the battery 15 is consumed as the actual use area of the battery 15. If power is consumed in an area other than the actual usage area of the battery 15 (an area higher than the upper limit capacity SOC and an area lower than the lower limit capacity SOC), an output shortage occurs or the battery 15 deteriorates. Therefore, it is necessary to charge the battery 15 by appropriately setting the actual usage area.

  Next, a charging control method for the battery 15 of the electric vehicle 10 configured as described above will be described using a flowchart.

  As shown in FIG. 4, in step S11, whether or not the battery 15 is being charged is detected based on an instruction from the charge detection unit 41 of the ECU 16. If the battery 15 is being charged, the process proceeds to step S12. The process ends. Whether or not the battery 15 is being charged is determined by, for example, detecting whether or not an external power source is connected to the charging connector 17 of the electric vehicle 10, or a charging start switch provided in the electric vehicle 10. It may be determined based on whether or not (not shown) is in an ON state.

  In step S12, date information is acquired by the detection unit 42, and the process proceeds to step S13. Note that the date information may use date information of the on-vehicle clock of the electric vehicle 10, automatically acquire date information using the GPS unit 30, or acquire date information manually. .

  In step S13, the location (position information) of the electric vehicle 10 is acquired using the GPS unit 30 according to an instruction from the detection unit 42, and the process proceeds to step S14. The position information of the electric vehicle 10 may use the final position information of the vehicle, may be acquired automatically using GPS, or may be acquired manually. Further, when the time difference between the travel end time of the electric vehicle 10 and the acquisition time of the final position information is large, the position information acquisition means may be switched to another means.

  In step S <b> 14, the travel range of the electric vehicle 10 is set according to an instruction from the travel range setting unit 45 of the ECU 16. Thereafter, the daily minimum temperature information of each point registered in the travel range is collated, the daily minimum temperature information in the travel range is acquired, and the process proceeds to step S15. In addition, you may progress to step S15, without performing this step S14. Further, the daily minimum temperature information may be acquired using an external communication means or may be acquired manually.

  In step S15, the deterioration state of the battery 15 is detected by an instruction from the battery state detection unit 46, and the process proceeds to step S16.

  In step S16, the lower limit capacity SOC of the battery 15 is set by an instruction from the capacity setting unit 43 of the ECU 16, and the process proceeds to step S17. The lower limit capacity SOC may be set from, for example, a date map and a temperature-lower limit capacity SOC map stored in the storage unit 44. The date map stores a maximum temperature and a minimum temperature corresponding to the date at the location of the electric vehicle 10. Then, the lowest temperature is extracted from the date map, and the lower limit capacity SOC is set using the temperature-lower limit capacity SOC map shown in FIG. Further, the date map may be switched or the value of the lower limit capacity SOC may be corrected by a preset correction equation according to the deterioration state of the battery 15 detected in step S15.

  In step S17, the upper limit capacity SOC of the battery 15 is set by an instruction from the capacity setting unit 43 of the ECU 16, and the process proceeds to step S18. The upper limit capacity SOC may be set from the date map and the temperature-upper limit capacity SOC map stored in the storage unit 44, for example, in substantially the same manner as in step S16. Alternatively, a lower limit capacity SOC-upper limit capacity SOC map shown in FIG. 6 may be used. When using the lower limit capacity SOC-upper limit capacity SOC map, the upper limit capacity SOC corresponding to the value of the lower limit capacity SOC set in step S16 may be set. Further, the date map may be switched or the value of the upper limit capacity SOC may be corrected by a correction formula according to the deterioration state of the battery 15 detected in step S15. Note that the upper limit capacity SOC and the lower limit capacity SOC are set such that the width of the actual use area is substantially constant.

  In step S18, it is determined whether or not the charging of the battery 15 is completed. If the charging of the battery 15 is not completed, step S18 is repeated, and if the charging is completed, the process is terminated as it is.

Here, a method for setting the lower limit capacity SOC and the upper limit capacity SOC will be specifically described.
First, the first example will be described. FIG. 7 is a graph showing the daily minimum temperature by month from 1989 to 2009 at a point A. The electric vehicle 10 stores daily minimum temperature information for a plurality of points. In the above-described flowchart, when it is determined that the location of the electric vehicle 10 corresponds to the point A, the minimum temperature information of the point A shown in FIG. 7 is referred to. Then, the daily minimum temperature is extracted from the date information when charging, and the daily minimum temperature is set as the battery minimum temperature predicted value.

  FIG. 8 is a table showing the setting result of the upper limit capacity SOC. The battery minimum temperature predicted value is classified in increments of 10 ° C., and the lower limit capacity SOC corresponding to the lowest temperature in the classified daily minimum temperature, for example, −20 ° C. when the daily minimum temperature is −20 ° C. to −10 ° C. Set to 23% from FIG. When the lower limit capacity SOC is set to 23%, the upper limit capacity SOC is set to 92% using FIG. Similarly, the lower limit capacity SOC and the upper limit capacity SOC are set for other classifications.

  Next, a second example will be described. FIG. 9 is a diagram illustrating a positional relationship between the current value and the travel range of the electric vehicle 10 and the B point and the C point. Similarly to the above, the electric vehicle 10 stores daily minimum temperature information for a plurality of points. FIG. 10 is a graph showing the daily minimum temperatures by month from 1989 to 2009 at point B and point C. The travel range is set by the travel range setting unit 45 of the ECU 16 and indicates a distance (range) in which the electric vehicle 10 can travel in a fully charged state.

  If this travel range is not taken into account, the daily minimum temperature information of the closest point (for example, B point) is extracted from the position information, or the date of a plurality of adjacent points (for example, B point and C point) The battery minimum temperature prediction value is set by extracting the minimum temperature information and calculating the average temperature.

  When considering the driving range, extract the lowest daily temperature information that is the lowest temperature from all points included in the driving range, or use the interface of the car navigation system and the user (driver) A point at which the temperature information is extracted is selected, and the minimum temperature information at the point is extracted, and the battery minimum temperature predicted value is set.

  FIG. 11 is a table showing the setting results of the upper limit capacity SOC. The battery minimum temperature predicted value is classified in increments of 10 ° C., and the lower limit capacity SOC corresponding to the lowest temperature in the classified daily minimum temperature, for example, −20 ° C. when the daily minimum temperature is −20 ° C. to −10 ° C. Set to 23% from FIG. When the lower limit capacity SOC is set to 23%, the upper limit capacity SOC is set to 92% using FIG. Similarly, the lower limit capacity SOC and the upper limit capacity SOC are set for other classifications.

  According to this embodiment, the battery 15 can ensure a predetermined actual use area under any environment. Therefore, the battery 15 can be used efficiently and the life of the battery 15 can be improved.

  In addition, since the location map storing the upper limit capacity SOC and the lower limit capacity SOC corresponding to the location of the electric vehicle 10 and the date map storing the upper limit capacity SOC and the lower limit capacity SOC corresponding to the date are stored, It is only necessary to extract the upper limit capacity SOC and the lower limit capacity SOC of the battery 15 from a previously stored map. Therefore, the setting process of the upper limit capacity SOC and the lower limit capacity SOC can be performed quickly. The map to be stored may be a seasonal map in which the upper limit capacity SOC and the lower limit capacity SOC corresponding to the season are stored.

  Furthermore, since the travel range of the electric vehicle 10 is set based on the location of the electric vehicle 10 and the capacity of the battery 15, when the electric vehicle 10 is stopped in a low-temperature environment, the temperature of the battery 15 becomes the lowest temperature over time. Therefore, the battery 15 can be efficiently charged even if the weather conditions fluctuate by using the minimum temperature information in the traveling range.

  And since the battery state detection part which detects the deterioration state of the battery 15 was provided, since the upper limit capacity | capacitance SOC and the lower limit capacity | capacitance SOC of the battery 15 can be set more appropriately, the battery 15 can be used more efficiently. In addition, the life of the battery 15 can be improved.

  The present invention is not limited to the above-described embodiment, and includes various modifications made to the above-described embodiment without departing from the spirit of the present invention. That is, the specific structure and shape described in the embodiment are merely examples, and can be changed as appropriate.

  For example, in the present embodiment, it has been described that the deterioration information of the battery 15 may be acquired in step S15 of the flowchart, and the values of the lower limit capacity SOC and the upper limit capacity SOC may be corrected in steps S16 and S17. For example, it may be set so that the process is not performed until the usage period of the battery 15 passes a certain period. Note that the deterioration state of the battery 15 may be determined by detecting an output value or a current value.

  Further, in the present embodiment, the case where the storage unit is configured to store the location map, the season map, and the date map has been described. However, only one or two may be stored.

  In this embodiment, the GPS unit 30 is used to obtain the vehicle location and date information. However, the vehicle is equipped with a network device so that various information can be obtained using the Internet. May be.

  Further, in this embodiment, the case where various maps are stored in the storage unit 44 of the ECU 16 has been described. However, the present invention is not limited to this, and the latest data is stored via the external communication means such as the GPS unit 30 or the Internet. You may comprise so that it may acquire.

  In the present embodiment, an electric vehicle (four-wheeled vehicle) has been described as an electric vehicle. However, the present invention can also be applied to an electric motorcycle or an electric cart.

  DESCRIPTION OF SYMBOLS 10 ... Electric vehicle (vehicle) 15 ... Battery 16 ... ECU 30 ... GPS unit (external communication means) 41 ... Charge detection part 42 ... Detection part 43 ... Capacity setting part 44 ... Memory | storage part 45 ... Traveling range setting part 46 ... Battery state Detection unit

Claims (5)

In a battery control device that controls a remaining capacity of a battery mounted on a vehicle to an actual use region between an upper limit capacity and a lower limit capacity,
A detection unit for detecting at least one of the location, season and date of the vehicle;
A capacity setting section for setting the upper limit capacity and the lower limit capacity based on the detection result of the detection section;
A charge detection unit for detecting whether or not the battery is being charged,
The capacity setting unit sets the upper limit capacity and the lower limit capacity so that a width of the actual use area becomes substantially constant when the charge detection unit detects that the battery is being charged. A battery control device. A location map storing the upper limit capacity and the lower limit capacity corresponding to the location, a season map storing the upper limit capacity and the lower limit capacity corresponding to the season, and the upper limit capacity and the lower limit corresponding to the date A storage unit for storing at least one of the date maps in which the capacity is stored;
The battery control device according to claim 1, wherein the capacity setting unit extracts and sets the upper limit capacity and the lower limit capacity from the storage unit based on a detection result of the detection unit. A location map storing the upper limit capacity and the lower limit capacity corresponding to the location, a season map storing the upper limit capacity and the lower limit capacity corresponding to the season, and the upper limit capacity and the lower limit corresponding to the date An external communication means capable of acquiring at least one of the date maps in which the capacity is stored;
2. The battery control device according to claim 1, wherein the capacity setting unit extracts and sets the upper limit capacity and the lower limit capacity from the acquired map based on a detection result of the detection unit. . A travel range setting unit for setting a travel range of the vehicle from the location of the vehicle and the capacity of the battery;
The capacity setting unit extracts the lowest temperature point having the lowest temperature information from the points included in the set travel range, and sets the upper limit capacity and the lower limit capacity based on the extraction result. The battery control device according to any one of claims 1 to 3. A battery state detection unit for detecting a deterioration state of the battery;
5. The battery control device according to claim 1, wherein the capacity setting unit corrects the upper limit capacity and the lower limit capacity based on a detection result of the battery state detection unit.

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