JP7110594B2 - Electric car - Google Patents

Description

The present invention relates to electric vehicles.

Conventionally, this type of electric vehicle includes a motor and a battery that exchanges electric power with the motor. (Battery output is reduced) has been proposed (see Patent Document 1, for example).

JP-A-2000-92603

As described above, in electric vehicles, when the SOC of the battery is low, the control allowable output of the battery is limited to a small value. On the other hand, if the control allowable output of the battery is limited, the output of the motor will decrease, resulting in a decrease in driving performance and a deterioration in drivability. Therefore, it is preferable to reduce the chances of limiting the control allowable output of the battery.

A main object of the electric vehicle of the present invention is to suppress deterioration of drivability.

The electric vehicle of the present invention employs the following means in order to achieve the above main object.

The electric vehicle of the present invention is
a running motor,
a power storage device that exchanges electric power with the motor;
a control device that controls the motor within the range of the allowable output for control of the power storage device and limits the allowable output for control when the power storage rate of the power storage device is equal to or less than a first rate;
An electric vehicle comprising
When it is predicted that the control device can reach an operating charging facility that is an operating charging facility, the control device allows the control allowable output when the power storage rate of the power storage device is equal to or lower than a second rate lower than the first rate. limit the
This is the gist of it.

In the electric vehicle of the present invention, the motor is controlled within the allowable output for control of the power storage device, and the allowable output for control is limited when the power storage rate of the power storage device is equal to or less than the first rate. Then, when it is predicted that an operating charging facility, which is an operating charging facility, can be reached, the allowable output for control is restricted when the power storage rate of the power storage device is equal to or lower than a second rate which is lower than the first rate. As a result, it is possible to prevent the allowable output for control from being limited until the vehicle reaches the operating charging facility, or it is possible to lengthen the time or travel distance until the allowable output for control is limited. As a result, deterioration of drivability can be suppressed. Here, the first ratio and the second ratio are determined as values higher than the control lower limit ratio of the power storage device.

In the electric vehicle of the present invention, the control device may limit the control allowable output when the power storage rate of the power storage device is equal to or less than the first rate when the operation information of the charging facility cannot be obtained. . When the operation information of the charging facility cannot be acquired, it is unknown whether the charging facility is in operation (whether the charging facility can charge the power storage device) until the vehicle actually reaches the charging facility. For this reason, when the operation information of the charging facility cannot be acquired, in order to suppress the power storage rate of the power storage device from reaching the lower limit rate for control or less, the allowable output for control is set when the power storage rate of the power storage device is equal to or less than the first rate. is preferably limited. Here, "when the operation information of the charging equipment cannot be acquired" can be mentioned when communication with the system outside the vehicle (for example, a cloud server, each charging equipment, etc.) cannot be performed.

In the electric vehicle of the present invention, the control device may notify the operating charging facility when the power storage rate of the power storage device reaches a third rate or less, which is higher than the first rate. In this way, the user can be made to recognize the operating charging equipment.

1 is a configuration diagram showing a schematic configuration of an electric vehicle 20 as an embodiment of the present invention; FIG. 5 is a flowchart showing an example of a limit start threshold value setting routine executed by an electronic control unit 50; FIG. 4 is an explanatory diagram showing an example of a relationship between a charge ratio SOC of a battery 36, a basic allowable output Wouttmp, and a control allowable output Wout when a temperature Tb of the battery 36 is a certain temperature;

Next, a mode for carrying out the present invention will be described using examples.

FIG. 1 is a configuration diagram showing the outline of the configuration of an electric vehicle 20 as one embodiment of the present invention. The electric vehicle 20 of the embodiment includes a motor 32, an inverter 34, a battery 36 as a power storage device, a charger 40, and an electronic control unit 50, as shown.

The motor 32 is configured as, for example, a synchronous generator-motor, and is connected to a drive shaft 26 whose rotor is connected to drive wheels 22a and 22b via a differential gear 24. As shown in FIG. The inverter 34 is used to drive the motor 32 and is connected to the battery 36 via the power line 38 . The motor 32 is rotationally driven by the switching control of a plurality of switching elements (not shown) of the inverter 34 by the electronic control unit 50 . The battery 36 is configured as, for example, a lithium-ion secondary battery or a nickel-hydrogen secondary battery.

The charger 40 is connected to a power line 38, and a vehicle-side connector 42 at home or a charging station is connected to a facility-side connector 92 from an external power source 91 such as a household power source or an industrial power source in the charging facility 90. The battery 36 can be charged using the power from the external power source 91 when the power is on. This charger 40 is controlled by an electronic control unit 50 .

Although not shown, the electronic control unit 50 is configured as a microprocessor centered on a CPU. Equipped with ports.

Signals from various sensors are input to the electronic control unit 50 through input ports. Signals input to the electronic control unit 50 include, for example, the rotational position θm of the rotor of the motor 32 from a rotational position sensor (not shown) that detects the rotational position of the rotor of the motor 32, and the phase of each phase of the motor 32. Phase currents Iu, Iv, and Iw of each phase of the motor 32 from a current sensor (not shown) that detects the current can be mentioned. Further, the voltage Vb of the battery 36 from the voltage sensor 36a attached between the terminals of the battery 36, the current Ib of the battery 36 from the current sensor 36b attached to the output terminal of the battery 36, the temperature attached to the battery 36 The temperature Tb of the battery 36 from the sensor 36c can also be mentioned. A connection detection signal from a connection detection sensor 43 attached to the vehicle-side connector 42 and detecting connection between the vehicle-side connector 42 and the facility-side connector 92 can also be used. The ignition signal from the ignition switch 60 and the shift position SP from the shift position sensor 62 that detects the operating position of the shift lever 61 can also be mentioned. The accelerator opening Acc from an accelerator pedal position sensor 64 that detects the amount of depression of the accelerator pedal 63, the brake pedal position BP from a brake pedal position sensor 66 that detects the amount of depression of the brake pedal 65, and the vehicle speed V from a vehicle speed sensor 68. , the current location of the vehicle from the GPS antenna 69 can also be mentioned.

Various control signals are output from the electronic control unit 50 through the output port. The signals output from the electronic control unit 50 include, for example, a control signal to the inverter 34, a control signal to the charger 40, a control signal to the display device 70 that displays information, and a control signal to the warning light 71. can be mentioned.

The electronic control unit 50 calculates the charging ratio SOC of the battery 36 based on the integrated value of the input/output current Ib of the battery 36 from the current sensor 36b, and calculates the calculated charging ratio SOC and the temperature of the battery 36 from the temperature sensor 36c. Tb, the basic allowable output Wouttmp that may be output from the battery 36 is calculated. Here, the power storage ratio SOC is the ratio of the capacity of electric power that can be discharged from the battery 36 to the total capacity of the battery 36 . Further, the electronic control unit 50 calculates the electricity consumption Ev as the traveled distance per unit electric energy based on the traveling history.

Further, the electronic control unit 50 is configured to be able to communicate wirelessly with the cloud server CS. The cloud server CS is configured to be able to wirelessly communicate with each vehicle including the electric vehicle 20, and stores map information, travel history information of each vehicle, and the like. Here, the map information includes service information (for example, information on the location and operation (business) hours of facilities, parking lots, charging facilities, etc.), and predetermined travel sections (for example, between traffic lights and intersections). etc.). Road information includes distance information, width information, number of lanes information, area information (urban areas and suburbs), type information (general roads, highways, toll roads), slope information, legal speed, number of traffic lights, etc. . The travel history information includes past travel routes, travel dates and times, parking locations, parking dates and times, and the like.

In the electric vehicle 20 of the embodiment thus configured, the electronic control unit 50 sets the required torque Td* required for running (required for the drive shaft 26) based on the accelerator opening Acc and the vehicle speed V. , the control allowable output Wout based on the basic allowable output Wouttmp of the battery 36 is divided by the rotation speed Nm of the motor 32 to set the control allowable torque Tmax of the motor 32, and the required torque Td* is set to the upper limit of the control allowable torque Tmax. A torque command Tm* for the motor 32 is set by guarding. Then, the switching control of the plurality of switching elements of the inverter 34 is performed so that the motor 32 is driven by the torque command Tm*.

When the storage rate SOC of the battery 36 reaches the control lower limit rate Smin (for example, 4%, 5%, 6%, etc.), the motor 32 is stopped and ready-off.

Further, when the power storage ratio SOC of the battery 36 is higher than the limit start threshold Slim which is higher than the control lower limit ratio Smin, the control allowable output Wout of the battery 36 is set to the basic allowable output Wouttmp. On the other hand, when the power storage rate SOC of the battery 36 reaches the limit start threshold Slim or less, the control allowable output Wout of the battery 36 is adjusted to prevent the power storage rate SOC of the battery 36 from reaching the control lower limit rate Smin or less. A value W1 smaller than the allowable output Wouttmp is set, and the warning light 71 is turned on to make the user aware that the control allowable output Wout is being limited. A method for setting the limit start threshold Slim will be described later. As the value W1, a value equal to or less than the basic permissible output Wouttmp when the charge ratio SOC of the battery 36 is the control lower limit ratio Smin is used.

In the electric vehicle 20 of the embodiment, when the vehicle-side connector 42 and the facility-side connector 92 are connected (when the connection detection sensor 43 detects the connection between the two) while the vehicle is parked at home or at a charging station, the electronic control unit 50 controls the charger 40 so that the battery 36 is charged using the power from the external power supply 91, and stops driving the charger 40 when the charging rate SOC of the battery 36 reaches a predetermined rate Smax. Hereinafter, such charging of the battery 36 using power from the external power supply 91 is referred to as "external charging". As the predetermined ratio Smax, for example, 90%, 95%, 100%, etc. are used.

Next, the operation of the electric vehicle 20 of the embodiment configured as described above, in particular, the operation when setting the limit start threshold Slim as the upper limit of the range of the power storage ratio SOC for limiting the control allowable output Wout of the battery 36 will be described. do. FIG. 2 is a flow chart showing an example of a limit start threshold value setting routine executed by the electronic control unit 50. As shown in FIG. This routine is executed when the vehicle starts running (when the ignition switch 60 is turned on).

When the restriction start threshold value setting routine of FIG. 2 is executed, the electronic control unit 50 first determines whether information (position and operating time) of the charging equipment can be acquired from the cloud server CS (step S100). . This determination process can be performed, for example, by determining whether or not communication with the cloud server CS is possible.

When it is determined in step S100 that the charging facility information can be acquired from the cloud server CS, the power storage ratio SOC of the battery 36 is input (step S110), and the input power storage ratio SOC of the battery 36 is compared with the threshold value Sref (step S120). ). Here, the threshold Sref is determined as a value higher than the limit start threshold Slim, such as 18%, 20%, or 22%.

When the state of charge SOC of the battery 36 is higher than the threshold Sref in step S120, the normal predetermined value S1 is set as the limit start threshold Slim (step S130), and whether or not to end the running (whether the ignition switch 60 is turned off) is determined. No) is determined (step S160). Here, for example, 14%, 15%, 16%, etc. are used as the predetermined value S1. When it is determined not to end the running, the routine returns to step S100, and when it is determined to end the running, the routine ends.

In step S120, when the charging ratio SOC of the battery 36 is equal to or less than the threshold value Sref, the charging equipment in operation based on the current location of the vehicle from the GPS antenna 69 and the charging equipment information (position and operating time) from the cloud server CS. A certain operating charging facility is searched for and displayed on the display device 70 (step S130), and it is predicted whether or not the operating charging facility can be reached (steps S140, S142). Then, when it is predicted that the operating charging facility cannot be reached, the processing from step S150 onwards is executed.

Here, in the embodiment, the nearest operating charging facility is considered as the operating charging facility. The prediction processing in steps S140 and S142 can be performed, for example, by comparing the travelable distance Ltd and the distance Lch to the nearest operating charging facility. The travelable distance Ltd can be calculated by multiplying the amount of electric power Wb that can be discharged from the battery 36 until the power storage ratio SOC of the battery 36 reaches the control lower limit ratio Smin by the electric power consumption Ev. The amount of electric power Wb can be calculated by multiplying the difference between the power storage rate SOC of the battery 36 and the lower limit rate for control Smin by a conversion coefficient k (a coefficient for converting the power storage rate into power amount). A value calculated based on the travel history can be used as the electricity consumption Ev.

When it is predicted in steps S140 and S142 that the vehicle can reach the operating charging facility, a predetermined value S2 lower than the predetermined value S1 is set as the limit start threshold Slim (step S170). Then, when it is determined that the running is finished (step S180), this routine is finished. Here, for example, 8%, 9%, 10%, etc. are used as the predetermined value S2. By such processing, it is possible to suppress the limitation of the control allowable output Wout until reaching the operating charging facility, or to lengthen the time or traveling distance until the control allowable output Wout is limited. As a result, deterioration of drivability can be suppressed.

Note that when external charging (charging of the battery 36 using electric power from the external power supply 91 of the charging equipment 90) is executed after the end of traveling and the state of charge SOC of the battery 36 becomes higher than the threshold value Sref, when the next traveling starts, In step S120, it is determined that the state of charge SOC of the battery 36 is higher than the threshold Sref, and the limit start threshold Slim is set to the predetermined value S1.

When it is determined in step S100 that the information on the charging facility cannot be acquired from the cloud server CS, the processing from step S150 onwards is executed. When information on the charging facility (in particular, information on operating time) cannot be acquired, it is necessary to check whether the charging facility is in operation (whether the battery 36 can be charged by the charging facility) until the charging facility is actually reached. ) is unknown. Therefore, when information on the charging facility cannot be obtained, it is preferable to set the limit start threshold Slim to a predetermined value S1 in order to prevent the state of charge SOC of the battery 36 from reaching the lower limit rate for control Smin or less.

FIG. 3 is an explanatory diagram showing an example of the relationship between the charge ratio SOC of the battery 36 and the basic allowable output Wouttmp and control allowable output Wout when the temperature Tb of the battery 36 is a certain temperature. In FIG. 3, the dashed line indicates the basic allowable output Wouttmp, the dashed line indicates the control allowable output Wout when the limit start threshold Slim is the predetermined value S1, and the solid line indicates when the limit start threshold Slim is the predetermined value S2. control allowable output Wout. Further, in a region where the power storage rate SOC of the battery 36 is greater than the threshold S1, the dashed line, the dashed line, and the solid line overlap, and in the region where the power storage rate SOC is greater than the threshold S2 and equal to or less than the threshold S1, the dashed line and the solid line overlap. , and the dashed line and the solid line overlap in a region where the power storage rate SOC is equal to or lower than the threshold value S2. As described above, when it is predicted that the vehicle can reach the operating charging facility, by setting the limit start threshold Slim to the predetermined value S2, as can be seen from the solid line in FIG. 3, the control allowable output Wout is less likely to be limited. can be done. As a result, it is possible to suppress the limitation of the control allowable output Wout until reaching the operating charging facility, or to lengthen the time or traveling distance until the control allowable output Wout is limited. As a result, deterioration of drivability can be suppressed.

In the electric vehicle 20 of the embodiment described above, the control allowable output Wout of the battery 36 is limited (predetermined value W1 sufficiently smaller than the basic allowable output Wouttmp) when the state of charge SOC of the battery 36 is equal to or lower than the limit start threshold Slim. ), a predetermined value S2 lower than the predetermined value S1 is set as the limit start threshold Slim when it is predicted that the vehicle can reach the operating charging facility. As a result, it is possible to prevent the control allowable output Wout from being limited until reaching the operating charging facility, or to lengthen the time or traveling distance until the control allowable output Wout is limited. As a result, deterioration of drivability can be suppressed.

In the electric vehicle 20 of the embodiment, when it is predicted that the vehicle can reach the operating charging facility, the limit start threshold Slim is set to a predetermined value S2 that is lower than the predetermined value S1. Therefore, a variable value S2va lower than the predetermined value S1 may be set. For example, as the variable value S2va, a value that tends to increase (approach the predetermined value S1) as the frequency of external charging decreases after the limit start threshold Slim has finished traveling with the variable value S2va in the past trip. It may be This is to prevent the power storage ratio SOC of the battery 36 from reaching the control lower limit ratio Smin or less in consideration of the execution frequency of external charging. As the variable value S2va, a value obtained by guarding the lower limit of the predicted power storage rate SOCes, which is predicted as the power storage rate SOC of the battery 36 when it reaches the operating charging facility, with the above-described predetermined value S2 may be used. By doing so, it is possible to prevent the restriction start threshold Slim from being excessively low (reduce it by a necessary amount).

In the electric vehicle 20 of the embodiment, when the charging facility information (position and operating time) can be obtained from the cloud server CS, the operating charging facility is searched based on the current location of the vehicle and the charging facility information from the cloud server CS. shall be. However, if an in-vehicle navigation device that stores map information (information including the location and operation time of the charging facility) similar to the cloud server CS is provided, the current location of the vehicle and charging facility information (position and operating time). Further, when the information of the charging facility can be acquired through communication with each charging facility, the operating charging facility may be searched based on the current location of the vehicle and the information from each charging facility.

In the electric vehicle 20 of the embodiment, the nearest operating charging facility is displayed on the display device 70 and whether or not the nearest operating charging facility can be reached is predicted. However, at least one operating charging facility (including the nearest operating charging facility) around the current location is displayed on the display device 70, and the user selects the destination (target operating charging facility) from the operating charging facility being displayed on the display device 70. is not set, it may be predicted whether or not the nearest operating charging facility can be reached, and when the destination is set by the user, it may be predicted whether or not the destination can be reached.

In the electric vehicle 20 of the embodiment, when the charging rate SOC of the battery 36 reaches the threshold value Sref or less, the operating charging facility is displayed on the display device 70. However, regardless of the charging rate SOC of the battery 36, the operating charging facility may be displayed on the display device 70 , or the operating charging equipment may not be displayed on the display device 70 .

The electric vehicle 20 of the embodiment is provided with the charger 40 that charges the battery 36 using the power from the external power source 91 when the vehicle-side connector 42 and the facility-side connector 92 are connected. In addition to or instead of the device 40, a charger that receives power from an external power supply in a non-contact manner to charge the battery 36 may be provided.

In the electric vehicle 20 of the embodiment, the battery 36 is used as the power storage device, but instead of the battery 36, a capacitor may be used.

The correspondence relationship between the main elements of the embodiments and the main elements of the invention described in the column of Means for Solving the Problems will be described. In the embodiment, the motor 32 corresponds to the "motor", the battery 36 corresponds to the "battery", and the electronic control unit 50 corresponds to the "control device".

Note that the correspondence relationship between the main elements of the examples and the main elements of the invention described in the column of Means for Solving the Problems is the Since it is an example for specifically explaining the mode for solving the problem, it does not limit the elements of the invention described in the column of the means for solving the problem. That is, the interpretation of the invention described in the column of Means to Solve the Problem should be made based on the description in that column, and the Examples are based on the description of the invention described in the column of Means to Solve the Problem. This is only a specific example.

Although the embodiments for carrying out the present invention have been described above, the present invention is not limited to such embodiments at all, and can be modified in various forms without departing from the scope of the present invention. Of course, it can be implemented.

INDUSTRIAL APPLICABILITY The present invention is applicable to the electric vehicle manufacturing industry and the like.

20 electric vehicle 22a, 22b drive wheel 24 differential gear 26 drive shaft 32 motor 34 inverter 36 battery 36a voltage sensor 36b current sensor 36c temperature sensor 38 power line 40 charger 42 vehicle side connector, 43 connection detection sensor, 50 electronic control unit, 60 ignition switch, 61 shift lever, 62 shift position sensor, 63 accelerator pedal, 64 accelerator pedal position sensor, 65 brake pedal, 66 brake pedal position sensor, 68 vehicle speed sensor, 69 GPS antenna, 70 display device, 71 warning light, 90 charging equipment, 91 external power supply, 92 equipment side connector, CS cloud server.

Claims (1)

a running motor,
a power storage device that exchanges electric power with the motor;
a control device that controls the motor within the range of the allowable output for control of the power storage device and limits the allowable output for control when the power storage rate of the power storage device is equal to or less than a first rate;
An electric vehicle capable of external charging that charges the power storage device using electric power from an external power supply of a charging facility,
When it is predicted that the control device can reach the operating charging facility, which is the charging facility in operation, the control tolerance is set when the power storage rate of the power storage device is equal to or lower than a second rate lower than the first rate. limit the output,
The second rate is set based on the frequency with which the external charging was carried out after the end of travel in past trips in which travel was completed at the second rate .
Electric car.

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