JP5730588B2 - Electric car - Google Patents

Description

  The present invention relates to control of an electric vehicle.

  2. Description of the Related Art In recent years, an electric vehicle that supplies electric power from a chargeable / dischargeable battery to a motor and travels only by the motor has been widely used. Such an electric vehicle, unlike a hybrid vehicle that travels by the power of the engine and motor, cannot charge the battery by itself, and when the remaining capacity (SOC) of the battery is reduced, either It is necessary to charge the battery by a charging station or a power source at home. Further, if the remaining capacity of the battery becomes too small, the life of the battery may be affected. For this reason, in such an electric vehicle, the remaining battery capacity (SOC) is surely warned to the driver more reliably than a vehicle in which an engine such as a conventional hybrid vehicle is mounted and the battery can be charged by itself. When it drops, it is necessary to reduce battery power consumption. Therefore, it has been proposed to detect a decrease in the battery terminal voltage and inform the driver of the decrease in the battery terminal voltage by the notification means, and to reduce the output of the drive motor (see, for example, Patent Document 1). ).

JP-A-9-294302

  On the other hand, drivability of a vehicle is required even for an electric vehicle. In the conventional electric vehicle described in Patent Document 1, even if the driver recognizes that the terminal voltage of the battery is reduced by turning on the warning lamp that informs the reduction of the terminal voltage of the battery. In addition, since it is not notified that the output of the drive motor is being reduced, it often feels that drivability has decreased as the terminal voltage of the battery has decreased. Also, since the degree of battery terminal voltage drop is unknown, whether it is possible to travel a considerable distance by traveling at a low speed for a while, or whether the electric vehicle must be evacuated to a nearby charging station immediately, etc. Judgment cannot be made, resulting in an overdischarged state of the battery, which may affect the life of the battery. Further, electric vehicles are required to have a longer cruising range. However, as in the prior art described in Patent Document 1, simply reducing the output of the drive motor simply by reducing the terminal voltage of the battery may not reduce the power consumption of the battery so much. There was a problem that the cruising range could not be made too long.

  Accordingly, an object of the present invention is to increase the cruising distance in an electric vehicle.

An electric vehicle according to the present invention includes a chargeable / dischargeable secondary battery, a traveling motor, an inverter that converts direct current power of the secondary battery into alternating current power for driving the traveling motor, a display, and a charging warning light. A warning display device including a travel restriction warning light, a low temperature warning light, and an overheat warning light, and an electric vehicle that travels by driving a traveling motor with electric power of the secondary battery, the vehicle speed of the electric vehicle, A control unit configured to limit at least one of the required power of the traveling motor and the output power of the secondary battery and turn on / off the display of the warning display device; and the control unit includes a remaining capacity of the secondary battery Is less than a predetermined capacity, required power limiting means for limiting the required power of the motor for traveling, and when the remaining capacity of the secondary battery is less than a predetermined capacity, the output of the secondary battery Electric Vehicle speed limiting means for limiting the vehicle speed, and when the remaining capacity of the secondary battery exceeds the predetermined capacity, the temperature of either the secondary battery, the driving motor, or the inverter is when exceeding the predetermined temperature range, the required power of the traction motor based on one of the temperature of the secondary battery or the traction motor or the inverter or to limit the output power of the secondary battery an output power limiting means, when the required power by limiting means or the output power limiting means required power of the traction motor limit or the output limit of the secondary batteries have been, or, the vehicle speed limiting means When the output restriction of the secondary battery and the vehicle speed are restricted by the above, a warning is displayed by each warning light according to the restriction state, and a restriction condition is displayed on the display. And a warning display means for displaying the description, the warning display means when the remaining capacity of the secondary battery has limited power required less traction motor than the predetermined capacity, the charge warning lamp And the travel restriction warning light are turned on, the explanation of the restricted state is displayed on the display, the remaining capacity of the secondary battery exceeds the predetermined capacity, the vehicle speed and the running state of the electric vehicle, and the secondary battery If the output power from the secondary battery is expected to be limited based on the remaining capacity of the battery, the driving restriction warning light is turned on, the other warning lights are turned off, and the display is in a restricted state. The remaining capacity of the secondary battery exceeds the predetermined capacity, and the temperature of the secondary battery, the driving motor or the inverter exceeds a predetermined temperature range, and the secondary battery Or for running When the required power of the traveling motor or the output power of the secondary battery is limited based on the temperature of either the motor or the inverter, either the low temperature warning lamp or the overheat warning lamp and the traveling A restriction warning light is turned on, and an explanation of the restriction state is displayed on the display .

  The present invention has an effect that a cruising distance can be increased in an electric vehicle.

1 is a system diagram showing a configuration of an electric vehicle according to an embodiment of the present invention. It is explanatory drawing which shows the display mounted in the electric vehicle in embodiment of this invention. It is a power control curve with respect to SOC stored in the memory of the control part of the electric vehicle in the embodiment of the present invention. It is an upper limit vehicle speed curve with respect to SOC stored in the memory of the control part of the electric vehicle in the embodiment of the present invention. It is an electric power control curve with respect to the temperature stored in the memory of the control part of the electric vehicle in the embodiment of the present invention. It is a flowchart which shows operation | movement of the electric vehicle in embodiment of this invention. It is a flowchart which shows other operation | movement of the electric vehicle in embodiment of this invention.

  Hereinafter, the electric vehicle of this embodiment will be described with reference to the drawings. As shown in FIG. 1, an electric vehicle 100 according to this embodiment includes a battery 11 that is a chargeable / dischargeable secondary battery, an inverter 12 that converts DC power of the battery 11 into three-phase AC power, and conversion by the inverter 12. The traveling motor 13 is driven by the three-phase AC power, the driving shaft 15 is driven by the output shaft 14 of the traveling motor 13, and the driving wheels 16 are attached to the driving shaft 15. The battery 11 is provided with a connection plug 19 for connecting to a charging station or a household power source so that the battery 11 can be charged at the charging station or the home. In addition, a temperature sensor 21 that detects the temperature of the battery 11 is attached to the battery 11. A voltage sensor 24 that detects an output voltage of the battery 11 and a current sensor 25 that detects an input / output current of the battery 11 are attached to a connection line between the battery 11 and the inverter 12. The inverter 12 includes a plurality of switching elements therein, and these switching elements generate heat when a switching operation is performed. A temperature sensor 22 for detecting the temperature is also attached to the switching element. The traveling motor 13 is a synchronous motor in which a coil is wound around a stator and a permanent magnet is attached to a rotor, and a temperature sensor 23 for detecting temperature is attached to the coil of the stator. A speed sensor 26 that detects the speed of the electric vehicle 100 by detecting the rotational speed of the drive shaft 15 is attached to the drive shaft 15. An accelerator opening sensor 27 that detects the accelerator opening from the amount of depression of the accelerator pedal 17 is provided in the accelerator pedal that is provided in the cab of the electric vehicle and is operated by the driver. The cab of the electric vehicle is provided with a front panel 18 in which a speedometer indicating the vehicle speed and various warning lights are incorporated.

  As shown in FIG. 2, a speedometer 31 is disposed in the center of the front panel 18, and a turtle mark-shaped travel limit warning light 32, a charging station-type charge warning light 33, and a heater are disposed below the speedometer 31. An overheat warning lamp 34 in the form of a thermometer and a low temperature warning lamp 35 in the form of a thermometer are arranged. Next to the speedometer 31, a display 36 having a diameter equal to or larger than the diameter of the speedometer 31, for example, 3.5 inches is disposed. In addition, the shape of each warning lamp 33-35 is an illustration, The indicator lamp which shows a warning, or a wording display etc. may be sufficient.

  As shown in FIG. 1, the electric vehicle 100 is provided with a control unit 50 that controls the running and display of the front panel 18 shown in FIG. 2. The control unit 50 includes a CPU 51 for processing information therein, a memory 53 for storing various data and programs, a sensor interface 52 for inputting signals from the sensors 21 to 27, and a speedometer included in the front panel 18. 31, each of the warning lights 32 to 35, and a display device interface 58 that outputs a signal to the display 36. In the memory 53, as will be described later, a battery SOC calculation program 54 executed by the CPU 51, a battery output possible power (Wout) calculation program 55, a required power calculation program 56 for calculating required power based on the operation of the driver, In addition, various limit curve data 57 referred to by the programs 54 to 56 are stored.

FIG. 3 shows the output power limit curve (line a) of the battery 11 and the required power limit curve (line b) of the motor 13 for the remaining capacity (SOC) of the battery 11 stored in the memory 53 shown in FIG. ing. As shown by the line a in FIG. 3, the output power of the battery 11, when the remaining capacity of the battery 11 (SOC) is higher than the SOC ₁ is the normal output power limit _{W 1,} the residual capacity of the battery 11 ( When SOC) is lower than SOC ₂ lower than SOC _{1, the} output power limit W ₂ is smaller than the normal output power limit W ₁ , and the remaining capacity (SOC) of the battery 11 is between SOC ₁ and SOC _2. In this case, it changes linearly between the output power limit W ₁ and the output power limit W ₂ as the SOC changes. Similarly, as shown by the line b in FIG. 3, the required power of the traveling motor 13 with respect to the remaining capacity (SOC) of the battery 11 is as follows when the remaining capacity (SOC) of the battery 11 is higher than SOC _1. a normal request power limit _{P 1,} remaining capacity (SOC) is less required power limit _{P 2} becomes than normal request power limit _{P 1} and if smaller than the lower SOC ₂ than SOC ₁ of battery 11, the battery 11 When the remaining capacity (SOC) is between SOC ₁ and SOC ₂ , it linearly changes between the required power limit P ₁ and the required power limit P _{2 as} the SOC changes.

FIG. 4 is a limit curve of the upper limit vehicle speed of the electric vehicle 100 with respect to the remaining capacity (SOC) of the battery 11 stored in the memory 53 shown in FIG. As shown in FIG. 4, the upper limit vehicle speed of the electric vehicle 100 is the normal upper limit vehicle speed V when the remaining capacity (SOC) of the battery 11 is higher than the SOC ₁ , as in the curves shown in FIG. 3. is _1, the remaining capacity (SOC) is less upper speed _{V 2} becomes than normal cruising speed _{V 1} was is smaller than a lower SOC ₂ than SOC ₁ of battery 11, the remaining capacity of the battery 11 (SOC) is SOC When it is between ₁ and SOC ₂ , it linearly changes between the upper limit vehicle speed V ₁ and the upper limit vehicle speed V _{2 as} the SOC changes.

FIG. 5 shows the output power limit curve of the battery 11 and the required power limit curve of the travel motor 13 with respect to the battery temperature, inverter element temperature, coil temperature of the travel motor 13 stored in the memory 53 shown in FIG. Yes. As shown by the line c in FIG. 5, the output power of the battery 11 is the normal output power limit W ₀ and the required power when the temperature of the battery 11 is lower than the predetermined temperature T _{1 and} higher than the temperature _TL. When the limit is P ₀ and the temperature of the battery 11 is lower than the predetermined temperature _TL , the normal output power limit W ₀ , the output power limit W ₃ lower than the required power limit P ₀ , and the required power limit P ₃ Gradually decreases. When the temperature of the battery 11 exceeds the predetermined temperature T ₁ of the output power limiter with increasing temperature of the battery 11, the required power limit becomes smaller. Further, as shown by the line d in FIG. 5, when the coil temperature of the traveling motor 13 is lower than the predetermined temperature T _{2 and} higher than the temperature T _L , the normal output power limit W ₀ and the required power limit P _0, if the coil temperature of the traveling motor 13 has exceeded a predetermined temperature T _2, the increase of the coil temperature with the output power and torque limit of the traction motor 13, the required power limit becomes smaller . Similarly, as shown by the line e in FIG. 5, when the temperature of the element of the inverter 12 is lower than the predetermined temperature T _{3 and} higher than the temperature _TL , the normal output power limit W ₀ and the required power limit P _0, when the temperature of the elements of the inverter 12 exceeds a predetermined temperature T _3, the temperature rise with the output power and torque limit of the elements of the inverter 12, the required power limit becomes smaller.

In the present embodiment, the normal battery output power limit W ₀ and the normal required power limit P ₀ have the same size, and the output power limit W ₃ and the required power limit P ₃ are also described as being the same. As shown in FIG. 3, the required power limits P ₀ and P ₃ may be set lower than the battery output power limits W ₀ and W ₃ , respectively.

  The operation of the electric vehicle 100 of the present embodiment configured as described above will be described with reference to the flowchart of FIG. As shown in step S <b> 101 of FIG. 6, the CPU 51 of the control unit 50 outputs a command for acquiring the output voltage of the battery 11 from the voltage sensor 24. With this command, the control unit 50 acquires the output voltage of the battery 11 through the sensor interface 52 and stores it in the memory 53. As shown in step S <b> 102 of FIG. 6, the CPU 51 outputs a command for acquiring the output current of the battery 11 from the current sensor 25. With this command, the control unit 50 acquires the output current of the battery 11 through the sensor interface 52 and stores it in the memory 53. As shown in step S <b> 103 of FIG. 6, the CPU 51 executes the battery SOC calculation program 54 stored in the memory 53, and the battery from the output voltage and output current of the battery 11 acquired from the voltage sensor 24 and the current sensor 25. The remaining capacity (SOC) of 11 is calculated. For example, the SOC may be calculated based on a curve indicating the relationship between the output voltage and the output current of the battery, or the open-end voltage when the output current of the battery 11 is zero is acquired. The SOC may be calculated, or the output power of the battery 11 may be calculated from the output voltage and output current, and the output power may be integrated and subtracted from the initial SOC.

  When the calculation of the SOC of the battery 11 is completed, the CPU 51, as shown in step S104 of FIG. 6, the temperature sensor 21 of the battery 11, the temperature sensor 22 provided in the element of the inverter 12, and the temperature provided in the coil of the travel motor 13 Commands for obtaining the temperature of the battery 11 and the elements of the inverter 12 and the temperature of the coil of the traveling motor 13 are output from the sensor 23, respectively. In response to this command, the control unit 50 acquires each temperature through the sensor interface 52 and stores it in the memory 53. Each of these temperatures is referred to as a unit temperature because it is a temperature representative of each unit of the battery 11, the inverter 12, and the traveling motor 13.

As shown in step S105 in FIG. 6, the CPU 51 determines whether or not the remaining capacity (SOC) of the battery 11 calculated by executing the battery SOC calculation program 54 is lower than the predetermined SOC ₁ shown in FIG. . When the remaining capacity (SOC) of the battery 11 is lower than the predetermined SOC ₁ , the CPU 51 determines that it is necessary to limit the travel of the electric vehicle 100 as shown in step S <b> 106 in FIG. 6. 11 is turned on to indicate that the remaining capacity (SOC) of 11 is low and charging is required. Then, the turtle mark-shaped travel restriction warning light 32 (output reduction warning light) shown in FIG. 2 is turned on. The SOC threshold value for turning on the travel restriction warning light 32 may be smaller than a predetermined SOC ₁ for turning on the charging warning light 33 indicating that charging is required. Further, the CPU 51 outputs a command for displaying, for example, a character “limiting upper limit vehicle speed due to lowering of SOC” on the display 36 shown in FIG. In response to this command, the display device interface 58 outputs a signal for turning on the warning lights 32 and 33 and a character signal to be displayed on the display 36. The warning lights 32 and 33 are turned on by this signal, and a warning message is displayed on the display 36.

Then, the CPU 51 limits the power of the electric vehicle 100 as shown in step S107 of FIG. For example, the power limitation outputs a command for limiting the output power from the battery 11 as shown by a line a in FIG. This command operation of the switching elements of the inverter 12 is changed by, as defined by line a in FIG. 3, the remaining capacity (SOC) is W from W ₁ output power limitation When lower than SOC ₁ of battery 11 _It begins to decline toward ₂ . When the remaining capacity (SOC) of the battery 11 becomes lower than the SOC ₂ , power larger than the output power limit W ₂ is prevented from flowing from the battery 11 to the travel motor 13. Further, the required power of the traveling motor 13 may be limited as shown by the line b in FIG. In this case, the CPU 51 of the control unit 50 calculates the required power of the traveling motor 13 by executing the required power calculation program 56 of the electric vehicle 100 in the memory 53 based on the accelerator opening obtained from the accelerator opening sensor 27. Keep it. Then, when the remaining capacity of the battery 11 (SOC) is lower than the SOC _1, required power limit starts to decrease towards the _{P 1} to _{P 2,} is the remaining capacity of the battery 11 (SOC) is lower than SOC ₂ When even if the driver depresses the accelerator pedal 17, drives the electric vehicle 100 requests power limit P ₂ as the required power in place of the calculation result of the power demand calculation program 56 as required driving force of the traction motor 13. In this manner, so that the supply power to the traction motor 13 does not become larger than the required power limit P _2. Regardless of which curve is used, when the remaining capacity (SOC) of the battery 11 is reduced, the discharge power from the battery 11 is suppressed, and driving using a region with high system efficiency where the loss of the motor or the like is small. By limiting the range, the cruising range can be extended.

Further, as shown in step S107 of FIG. 6, the CPU 51 limits the upper limit speed of the electric vehicle 100 by applying the curve shown in FIG. As shown in FIG. 4, when the remaining capacity (SOC) of the battery 11 becomes lower than SOC ₁ , the upper limit speed of the electric vehicle starts to decrease from the normal upper limit speed V ₁ to V _2, and the remaining capacity of the battery 11 (SOC) is the way is not to be traveling faster than the upper limit speed _{V 2} When is lower than the SOC _2. As a result, traveling at low speed with low traveling resistance is continued, and the cruising distance of the electric vehicle 100 can be extended.

  As described above, since the travel of the electric vehicle 100 is restricted, even if the driver depresses the accelerator pedal 17 greatly, the acceleration is slower than the normal state and the speed is lower. Since it is possible to know the driving state of the electric vehicle 100 in more detail by displaying the warning lights 32 and 33 or the characters on the display 36, the remaining capacity (SOC) of the battery 11 needs to be charged, not simply reduced in drivability. It is possible to clearly recognize that the travel restriction is caused by the fact that the state has been lowered to the state. For this reason, it can be expected that the driver will drive without consuming more power, and the evacuation traveling to the charging station can be made smoother. Moreover, since the retreat travel to the charging station is performed while suppressing a decrease in the remaining capacity (SOC) of the battery 11, overdischarge can be suppressed and the life of the battery 11 can be maintained.

If the remaining capacity (SOC) of the battery 11 is larger than the predetermined SOC ₁ in step S105 of FIG. 6, the CPU 51 determines whether there is an output limitation due to the characteristics of the battery 11 as shown in step S108 of FIG. Check if. For example, even when the remaining capacity of the battery 11 is larger than a predetermined SOC ₁ , the output power may be limited in order to suppress deterioration and overheating of the battery, for example, when a large output power is requested continuously. . This limitation is often determined by the accumulated capacity of the remaining capacity of the battery 11, the peak required driving force, and the current (battery output). However, since the required driving force at the peak always fluctuates, if the travel restriction warning light 32 is turned on / off by the peak driving force, the travel restriction warning light 32 repeatedly turns on and off. Therefore, when the output power limit from the battery 11 is expected to be generated based on the speed, the running state, and the remaining capacity (SOC) of the battery 11, the CPU 51, as shown in step S109 in FIG. The lamp 32 is turned on. By this display, the driver can avoid a sense of incongruity even when the travel restriction is actually performed.

Since the remaining capacity (SOC) of the battery 11 is larger than the predetermined SOC ₁ , the CPU 51 limits the power limit and the upper limit speed using the limit curves shown in FIGS. 3 to 4 as shown in step S110 of FIG. There are no restrictions.

When the CPU 51 determines in step S108 in FIG. 6 that there is a low possibility that the output from the battery 11 is limited by the characteristics of the battery 11, as shown in step S111 in FIG. It is determined whether the three elements, the three temperatures of the coil of the motor 13 for traveling, and these are called unit temperatures are within a predetermined temperature range. For example, as shown in FIG. 5, when the temperature of the battery 11 is between T _L and T ₁ , the output power of the battery 11 is not limited and the normal output power limit W ₀ is set. as shown in step S112 of, when the temperature of the battery 11 is lower than T _L, the output power limit of the battery 11 and a lower W ₃ than W _0, the low temperature warning light 35 indicating a low temperature state of the battery 11 Is displayed, and the display 36 displays, for example, characters “running restricted due to low battery temperature”. Further, when the temperature of the battery 11 is higher than T _1, the output power limit of the battery 11 gradually decrease in accordance with increase in temperature of the battery 11, as shown in line c of FIG. 5 than W _0, the battery 11 While the overheat warning lamp 34 indicating the overheat state is turned on, the display 36 displays, for example, a message “Running restricted due to overheating of the battery”. When the temperature of the coil of traction motor 13 is lower than T _L, also higher than T _2, perform limitation of the output power by line d in FIG. 5, it is turned low temperature warning light 35 or temperature warning light 34 The display 36 displays the words “running restricted due to low temperature of motor” or “running restricted due to overheating of motor”. If the temperature of the element of the inverter 12 is lower than T _L, also higher than T _3, perform limitation of the output power by line e in FIG. 5, it is turned low temperature warning light 35 or temperature warning light 34, a display 36 displays the words “running restricted due to low temperature of inverter element” or “running restricted due to overheating of inverter element”. The same applies to the case where the required power of the traveling motor 13 is limited by the lines c, d, and e in FIG.

  When there is no limitation on the output power from the battery 11 or the required power of the traveling motor 13 due to the unit temperature in step S111 in FIG. 6, the CPU 51 performs normal traveling as shown in step S113 in FIG. The travel restriction warning light 32 and the other warning lights 33, 34, and 35 are turned off and the display 36 is not displayed.

  As described above, the electric vehicle 100 according to this embodiment suppresses power consumption of the battery 11 by appropriately restricting travel when travel is necessary due to a decrease in the remaining capacity (SOC) of the battery 11 or the like. In addition, it is possible to notify the driver that the vehicle is in a travel-restricted state by turning on the warning lights 32 to 35 and displaying characters on the display 36, so that the driver can be prevented from feeling uncomfortable with drivability. Furthermore, since the driver can recognize that the travel is being restricted, the driver can be aware of power consumption, and as a result, the cruising distance can be increased.

  Next, another embodiment of the present invention will be described with reference to FIG. The same components as those described with reference to FIGS. 1 to 6 are denoted by the same reference numerals, and description thereof is omitted.

  First, as in steps S101 to S103 in FIG. 6, the CPU 51 obtains the output voltage and output current of the battery 11 and calculates the remaining capacity (SOC) of the battery 11 as shown in steps S201 to S203 in FIG. To do. Then, the CPU 51 executes the battery output possible power calculation program 55 shown in FIG. 1 and calculates the output possible power (Wout) of the battery 11. This calculation is performed based on the acquired output voltage, output current, battery temperature, and the like of the battery 11.

When the CPU 51 finishes calculating the output power (Wout) of the battery 11, it stores the calculation result in the memory 53. Next, as shown in step S <b> 205 in FIG. 7, the CPU 51 compares the calculated output power (Wout) of the battery 11 with a predetermined threshold output power α. This predetermined threshold output possible power α may be, for example, 50% of the normal maximum output possible power (Wout _max ) when the battery 11 is in a fully charged state. When the output power (Wout) of the battery 11 calculated earlier is less than a predetermined threshold output power α, the CPU 51 is caused by a decrease in the remaining capacity (SOC) of the battery 11 when the electric vehicle 100 is running. As shown in step S206 of FIG. 7, the travel restriction warning lamp 32 is turned on, and the display 36 displays, for example, “Due to severe travel restriction due to a decrease in battery output power”. "Is displayed.

Further, when the output power (Wout) of the battery 11 calculated in step S205 in FIG. 7 is larger than the predetermined threshold output power α, the CPU 51 calculates the calculated battery as shown in step S207 in FIG. 11 output possible power (Wout) and threshold output possible power β, for example, 75% of the normal maximum output possible power (Wout _max ) when the battery 11 is in a fully charged state, and the calculated battery 11 output possible When it is determined that the power (Wout) is less than the threshold output possible power β, the output possible power (Wout) of the battery 11 is larger than the threshold output possible power α and smaller than the threshold output possible power β. Judged that there may be minor driving restrictions. Then, as shown in step S208 of FIG. 7, the CPU 51 turns on the travel restriction warning lamp 32 and displays a phrase such as “lightly running restricted due to a decrease in battery output power” on the display 36. indicate. When the CPU 51 determines that the calculated output power (Wout) of the battery 11 is equal to or greater than the threshold output power β, the CPU 51 determines that the travel restriction by the battery 11 is not received, and the step of FIG. As shown in S209, the travel restriction warning light 32 is turned off, and the display 36 is not displayed.

  Next, as shown in step S210 of FIG. 7, the CPU 51 determines whether or not the remaining capacity (SOC) of the battery 11 is less than a predetermined remaining capacity γ. When it is determined that the remaining capacity (SOC) of the battery 11 is less than the predetermined remaining capacity γ, as shown in step S211 of FIG. 7, the limit curve shown in FIGS. 11, the required power of the driving motor 13 or the upper limit speed is limited, and the charging warning lamp 33 is blinked while the driving limit warning lamp 32 lit in step S206 of FIG. For example, the display 36 is changed to a wording such as “Severe travel restriction due to lowering of SOC”.

  When the CPU 51 determines in step S210 in FIG. 7 that the remaining capacity (SOC) of the battery 11 is equal to or greater than the predetermined remaining capacity γ, as shown in step S212 in FIG. Limiting the output power of the battery 11 using the curve, limiting the required power of the traveling motor 13 and limiting the upper limit speed are not performed, and the charging warning lamp 33 is not lit. Then, the display 36 is assumed to display the state displayed in steps S206, S208, and S209 of FIG.

  As described above, the electric vehicle 100 of the present embodiment also has the same effects as those of the embodiment described above with reference to FIGS.

  DESCRIPTION OF SYMBOLS 11 Battery, 12 Inverter, 13 Traveling motor, 14 Output shaft, 15 Drive shaft, 16 Drive wheel, 17 Accelerator pedal, 18 Front panel, 19 Connection plug, 21-23 Temperature sensor, 24 Voltage sensor, 25 Current sensor, 26 Speed sensor, 27 accelerator opening sensor, 31 speedometer, 32 travel limit warning light, 33 charge warning light, 34 overheat warning light, 35 low temperature warning light, 36 display, 50 control unit, 52 sensor interface, 53 memory, 54 battery SOC calculation program, 55 battery output possible power calculation program, 56 required power calculation program, 57 limit curve data, 58 display device interface, 100 electric vehicle.

Claims (1)

Rechargeable secondary battery, traveling motor, inverter for converting the DC power of the secondary battery to AC power for driving the traveling motor, display , charging warning light, travel limit warning light, low temperature A warning display device including a warning light and an overheat warning light, and an electric vehicle that travels by driving a traveling motor with electric power of the secondary battery,
A control unit that limits at least one of the vehicle speed of the electric vehicle, the required power of the driving motor, and the output power of the secondary battery, and turns on and off the display of the warning display device;
The controller is
When the remaining capacity of the secondary battery is less than a predetermined capacity, required power limiting means for limiting the required power of the traveling motor;
When the remaining capacity of the secondary battery is less than a predetermined capacity, vehicle speed limiting means for limiting the output power of the secondary battery and limiting the vehicle speed;
When the remaining capacity of the secondary battery exceeds the predetermined capacity and the temperature of any of the secondary battery, the driving motor, or the inverter exceeds a predetermined temperature range , the secondary battery or an output power limiting means the requested power of the traction motor based on one of temperature of the traveling motor or the inverter or to limit the output power of the secondary battery,
The required power limiting means or the output limit of restriction or the secondary battery of the power required by the traction motor by the output power limiting means is being performed, or the output of the secondary battery by the speed limiting means A warning display means for displaying a warning by the warning lights according to a restriction state and displaying a description of the restriction state on the display when the restriction and the vehicle speed are restricted ,
The warning display means includes
When the remaining capacity of the secondary battery is less than the predetermined capacity and the required power of the driving motor is limited, the charging warning lamp and the driving limit warning lamp are turned on, and the display explains the limit state To display
Expected that the remaining capacity of the secondary battery exceeds the predetermined capacity, and the output power from the secondary battery is limited based on the vehicle speed and running state of the electric vehicle and the remaining capacity of the secondary battery. If so, turn on the driving restriction warning light, turn off the other warning lights, display the explanation of the restriction state on the display,
The remaining capacity of the secondary battery exceeds the predetermined capacity, the temperature of the secondary battery, the traveling motor or the inverter exceeds a predetermined temperature range, and the secondary battery or the traveling motor or When the required power of the driving motor or the output power of the secondary battery is limited based on the temperature of any one of the inverters, either the low temperature warning light or the overheat warning light and the driving restriction warning An electric vehicle characterized in that a lamp is turned on and an explanation of a restricted state is displayed on the display .

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