JP2013090451A - Electric vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To protect electronic components mounted on an electric vehicle by restriction of charge/discharge of an electric storage device while suppressing degradation of drivability.SOLUTION: When a running condition in accordance with a request torque T*, that is, a running condition requested by a driver is in a state where it is highly possible that restriction of input limit and output limit Wout for protecting electronic components is started by a battery ECU, the driver is informed of that effect (yellow light emission of segments) and recommended vehicle velocity Vrcm through a meter display device (steps S140 and S150), and while the input limit and output limit Wout are restricted by the battery ECU, the driver is informed of that effect (yellow and red light emission of segments), the recommended vehicle velocity Vrcm, and the highest vehicle velocity Vmax.

Description

  The present invention relates to an electric vehicle including an electric motor capable of outputting driving power and a power storage device capable of exchanging electric power with the electric motor.

  Conventionally, as an electric vehicle including a vehicle driving motor and an inverter that drives the motor, temperature detecting means for detecting the temperature of the motor or inverter, temperature estimating means for estimating the temperature of the motor or inverter, temperature Of the temperature detection value detected by the detection means and the temperature estimation value estimated by the temperature estimation means, the temperature selection means for selecting a more reliable value, and the output of the motor is limited based on the selected value. A device provided with motor output limiting means is known (see, for example, Patent Document 1).

JP 2008-67280 A

  In the conventional electric vehicle, overheating of the inverter, which is an electronic component mounted on the motor or the electric vehicle, can be suppressed by limiting the output of the motor based on the detected temperature value and the estimated temperature value. However, since the motor output limitation as described above is performed regardless of the intention of the driver of the electric vehicle, the driver is given a sense of incongruity that the vehicle does not accelerate despite the request for acceleration. When the motor output is limited, the driver cannot know how to recover the original performance. Therefore, the above conventional technology still has room for improvement in terms of drivability of the electric vehicle.

  SUMMARY OF THE INVENTION Accordingly, it is a primary object of the present invention to protect electronic components mounted on an electric vehicle by limiting charge / discharge of a power storage device while suppressing deterioration of drivability.

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

The electric vehicle according to the present invention is
In an electric vehicle including an electric motor capable of outputting driving power and a power storage device capable of exchanging electric power with the electric motor,
An index indicating that an electronic component mounted on the electric vehicle is protected when it is equal to or less than a predetermined reference value is larger as the square value is larger based on the square value of the charge / discharge current of the power storage device. And an index calculation means for calculating so that the smaller the smaller,
Charge / discharge allowable power limiting means for limiting charge allowable power and discharge allowable power of the power storage device when the index calculated by the index calculation means exceeds the reference value;
When the driving state requested by the driver is a state in which there is a high possibility that the charging / discharging allowable power limiting means will start limiting the charging allowable power and discharging allowable power, the driver and the recommended vehicle speed are indicated. And notifying means for notifying the driver of the recommended vehicle speed and the maximum vehicle speed while the allowable charging power and the allowable discharging power are limited by the allowable charging / discharging power limiting means,
It is characterized by providing.

  In this electric vehicle, an index indicating that an electronic component mounted on the electric vehicle is protected when it is equal to or less than a predetermined reference value is based on the square value of the charge / discharge current of the power storage device. When the calculated index exceeds the reference value, the charging allowable power and discharging allowable power of the power storage device are limited to protect the electronic component. The When the driving state requested by the driver is a state where there is a high possibility that the restriction of the allowable charging power and the allowable discharging power is started, the driver is notified of that and the recommended vehicle speed. Further, while the allowable charging power and the allowable discharging power are limited, the driver is notified of the fact and the recommended vehicle speed and the maximum vehicle speed. As a result, when it becomes highly likely that restriction of allowable charging power and allowable discharging power is started to protect the electronic components, the allowable charging power and allowable discharging power will be provided to the driver in the future. It is possible to notify that there is a possibility that the restriction will be started, and to notify the recommended vehicle speed at which the original performance of the vehicle can be maintained without restricting the allowable charging power and the allowable discharging power. In addition, while the allowable charging power and the allowable discharging power are limited, the driver is informed so that the uncomfortable feeling is suppressed, and the above index is lowered to limit the allowable charging power and the allowable discharging power. It is possible to inform the driver of the recommended vehicle speed that enables the release of the vehicle, and the maximum vehicle speed that is permitted at that time, thereby assisting the execution of the driving according to the situation. As a result, it is possible to protect electronic components mounted on the electric vehicle by limiting charge / discharge of the power storage device while suppressing deterioration of drivability.

It is a schematic block diagram of the electric vehicle 20 which is an example of the electric vehicle by this invention. 3 is an explanatory diagram illustrating a meter display device 100 of the electric vehicle 20. FIG. It is explanatory drawing which shows an example of the map for request | requirement torque setting. It is a flowchart which shows an example of a meter display command setting routine.

  Next, embodiments for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic configuration diagram of an electric vehicle 20 which is an example of an electric vehicle according to the present invention. An electric vehicle 20 shown in the figure includes a motor MG that can input and output power to a drive shaft 22 connected to a drive wheel DW, an inverter 30 for driving the motor MG, and the motor MG and electric power via the inverter 30. And a main electronic control unit (hereinafter referred to as “main ECU”) 50 for controlling the entire vehicle.

  As shown in FIG. 1, the drive shaft 22 is connected to the left and right drive wheels DW via a differential gear 24 and the like. The motor MG is a known synchronous generator motor having a rotor in which a permanent magnet is embedded and a stator around which a three-phase coil is wound. The inverter 30 has, for example, six transistors as switching elements and six diodes connected in parallel to these transistors in the reverse direction, and is connected to the battery 40 via the boost converter 35. The step-up converter 35 has, for example, two transistors, two diodes connected in parallel to these transistors in the opposite direction, and a reactor (both not shown), and the voltage from the battery 40 is obtained. The voltage can be stepped up and supplied to the inverter 30, and the voltage from the inverter 30 can be stepped down and supplied to the battery 40.

  The battery 40 is, for example, a nickel hydride secondary battery or a lithium ion secondary battery having a rated output voltage of 200 to 300 V, and is a battery electronic control unit (hereinafter referred to as “battery”) configured as a microcomputer centering on a CPU (not shown). ECU ”) 45). The battery ECU 45 includes a terminal voltage Vb from a voltage sensor (not shown) installed between terminals of the battery 40, and a charge / discharge current Ib from a current sensor (not shown) installed in a power line connected to the output terminal of the battery 40. The battery temperature Tb of a temperature sensor (not shown) installed in the battery 40 is input. Further, the battery ECU 45 calculates the remaining capacity SOC indicating the charging rate of the battery 40 based on the integrated value of the charge / discharge current Ib, or is allowed to charge the battery 40 based on the remaining capacity SOC and the battery temperature Tb. An input limit Win as an allowable charge power (negative value) that is power and an output limit Wout as an allowable discharge power (positive value) that is allowable for the discharge of the battery 40 are calculated.

  Furthermore, the battery ECU 45 protects electronic components such as the inverter 30 and the step-up converter 35 mounted on the electric vehicle 20 and cables (wire harness) connected thereto, at predetermined intervals (for example, every 100 msec). The index M is calculated according to the following equation (1) based on the square value of the charge / discharge power Ib of the battery 50 proportional to the amount of heat applied to the electronic component. Here, the expression (1) is obtained from a differential equation of a first-order lag element, and “K” is a constant (weighting coefficient, 1 <K, for example) determined based on a time constant determined through experiments and analysis, for example. <2) where “previous M” is the index M obtained at the time of the previous index calculation (initial value = 0), and “Ib” is the charge / discharge current Ib of the battery 40 at the time of the current index calculation. is there. The index M increases as the square value of the charge / discharge current Ib of the battery 40 increases, and decreases as it decreases. Further, the index M indicates that when the charge / discharge current Ib is constant and the battery 40 is continuously charged or discharged by the step response of the first-order lag element, that is, the square value of the charge / discharge current Ib remains constant for a long time. When it changes, it converges to a constant value.

M = (K−1) · previous M + Ib ² / K (1)

  For such an index M, the rated current value of each electronic component such as the inverter 30 is taken into consideration, and even if the battery 40 is continuously charged or discharged for a long time while the charge / discharge current Ib is constant, the inverter 30 or the like. The reference value Mref is determined in advance based on the value (square value) of the charge / discharge current when the electronic component is reliably protected without causing smoke or damage. Accordingly, when the index M is equal to or less than the reference value Mref, it can be considered that the electronic components such as the inverter 30 mounted on the electric vehicle 20 are surely protected without causing smoke or damage.

  Then, when the index M exceeds the reference value Mref, the battery ECU 45 sets the charge / discharge limit flag Flim to the value 1 until the index M drops to a predetermined limit release threshold (Mref or a value smaller than Mref). In addition, the input limit Win and the output limit Wout of the battery 40 are limited so that the current value applied to the electronic component such as the inverter 30, that is, the charge / discharge current Ib becomes small. For example, when the index M exceeds the reference value Mref, the battery ECU 45 resets the input limit Win to a predetermined relatively large negative constant value, or sets a positive predetermined value to the separately set input limit Win. By adding, the input restriction Win is limited to be smaller (larger value) as the charging power. Further, when the index M exceeds the reference value Mref, the battery ECU 45 sets the output limit Wout to a predetermined relatively small positive value or subtracts a predetermined positive value from the separately set output limit Wout. By doing so, the output limit Wout is limited to a smaller value (smaller value) as the discharge power. The charge / discharge restriction flag Flim is set to a value of 0 when the index M reaches a predetermined restriction release threshold and the restrictions on the input restriction Win and the output restriction Wout based on the indicator M are released.

  The main ECU 50 is configured as a microprocessor centered on a CPU. In addition to the CPU, a ROM that stores various control programs, a RAM that temporarily stores data, an input / output port, and a communication port (all not shown) ) Etc. The main ECU 50 includes an ignition signal from an ignition switch (start switch) 80, a shift range SR from a shift range sensor 52 that detects a shift range SR corresponding to the operation position (shift position) of the shift lever 51, and an accelerator pedal 53. Accelerator opening (accelerator operation amount) Acc from the accelerator pedal position sensor 54 that detects the amount of depression, vehicle speed V from the vehicle speed sensor 57, road surface gradient θ from the gradient sensor 58 that detects the gradient of the traveling road surface of the electric vehicle 20, etc. Is input through the input port.

  In addition, the rotor rotational position from the rotational position detection sensor 31 that detects the rotational position of the rotor of the motor MG is input to the main ECU 50 via the input port, and the main ECU 50 receives the rotor rotational position from the rotational position detection sensor 31. Is used to calculate the electrical angle, rotational angular velocity, rotational speed Nm, and the like of the rotor of the motor MG. Further, the main ECU 50 includes a phase current flowing in, for example, the V phase and the W phase of the three-phase coil of the motor MG detected by a current sensor (not shown), between the battery 40 and the boost converter 35 detected by a voltage sensor (not shown). Voltage (voltage before boosting), voltage between boosting converter 35 and inverter 30 (voltage after boosting), and the like are input via the input port. The main ECU 50 outputs a switching control signal to the transistor of the inverter 30 and the transistor of the boost converter 35 via the output port.

  Further, the main ECU 50 is configured as a microcomputer centering on a CPU (not shown), and is used for a brake for controlling a hydraulic brake device (not shown) capable of applying a friction braking force to the drive wheels DW and other wheels (not shown). It communicates with an electronic control unit (hereinafter referred to as “brake ECU”) 60 and exchanges various signals and data with the brake ECU 60. As shown in the figure, a brake pedal stroke BS from a brake pedal stroke sensor 56 that detects the depression amount of the brake pedal 55 is input to the brake ECU 60 via an input port. When the brake pedal 55 is depressed by the driver, the brake ECU 60 calculates the pedal depression force applied to the brake pedal 55 by the driver based on the brake pedal stroke BS from the brake pedal stroke sensor 56, and calculates the pedal depression force. Based on this, the required braking force requested by the driver is set. Further, the brake ECU 60 sets a required regenerative braking torque for the motor MG using the set required braking force, the vehicle speed V, and a regenerative distribution ratio setting map prepared in advance, and sets the set required regenerative braking torque to the main ECU 50. The hydraulic brake device is controlled so as to output the friction braking force corresponding to the share.

  In addition, the main ECU 50 communicates with the battery ECU 45 and exchanges various signals and data with the battery ECU 45. The main ECU 50 is configured as a microcomputer centering on a CPU (not shown), and is an electronic control unit for meter (hereinafter referred to as “meter ECU”) that controls the meter display device 100 disposed near the driver's seat of the electric vehicle 20. The meter ECU 90 controls the meter display device 100 in accordance with a signal from the main ECU 50.

  The meter display device 100 is configured as a TFT display, for example, and includes a vehicle speed display unit 101 as shown in FIG. The vehicle speed display unit 101 includes a current vehicle speed display unit 102 that displays the current vehicle speed, a recommended vehicle speed display unit 103 that displays a recommended vehicle speed recommended when the electric vehicle 20 travels as necessary, and an electric vehicle 20 as necessary. A maximum vehicle speed display section 104 is provided for displaying the maximum vehicle speed allowed for the vehicle. Further, a scale of the vehicle speed is displayed on the outer periphery of the vehicle speed display unit 101, and a pointer 105 is displayed so as to indicate a position corresponding to the current vehicle speed of the scale. Further, a plurality of segments 106 that can emit light in a plurality of colors (in this embodiment, blue, yellow, and red) are arranged around the vehicle speed display unit 101. The segment 106 is arranged for each region obtained by dividing the range from the lowest vehicle speed (0 km / h) to the highest vehicle speed (for example, 180 km / h) into a plurality of equal parts.

  When the electric vehicle 20 configured as described above travels, the main ECU 50 outputs to the drive shaft 22 corresponding to the accelerator opening Acc and the vehicle speed V using a required torque setting map as illustrated in FIG. The required torque T * (including the braking torque when the accelerator is off) to be set is set. Further, at the time of vehicle braking in which the brake pedal 55 is depressed by the driver, the required regenerative braking torque from the brake ECU 60 is set as the required torque T *. Then, the main ECU 50 sets and sets the torque command Tm * of the motor MG so that torque according to the required torque T * is output to the drive shaft 22 within the range of the input limit Win and the output limit Wout of the battery 40. The inverter 30 and the boost converter 35 are subjected to switching control according to the torque command Tm * and the rotational speed Nm. When the ignition switch 80 is turned on, the main ECU 50 sets a meter display command for displaying information according to the state of the electric vehicle 20 on the vehicle speed display unit 101 of the meter display device 100, and sets the meter display thus set. The command is transmitted to the meter ECU 90.

  Next, a procedure for setting a meter display command by the main ECU 50 will be described. FIG. 4 is a flowchart showing an example of a meter display command setting routine executed by the main ECU 50 every predetermined time (for example, every several milliseconds) after the ignition switch 80 is turned on.

  At the start of the meter display command setting routine of FIG. 4, the main ECU 50 (CPU) determines the value of the charge / discharge limit flag Flim, the output limit Wout of the battery 40, the required torque T *, the vehicle speed V from the vehicle speed sensor 57, and the gradient sensor 58. Necessary data input processing such as road surface gradient θ from is executed (step S100). The value of the charge / discharge limit flag Flim and the output limit Wout of the battery 40 are input from the battery ECU 45 by communication. Further, the required torque T * is set separately by the main ECU 50 as described above.

  After the data input process in step S100, the main ECU 50 determines whether or not the charge / discharge restriction flag Flim has a value of 0 (step S110), and the charge / discharge restriction flag Flim has a value of 0 and is based on the index M. If the input limit Win and the output limit Wout are not limited, it is further determined whether or not the absolute value of the requested torque T * input in step S100 exceeds a predetermined reference torque Tref (positive value). (Step S120). The reference torque Tref as a threshold used in step S120 is, for example, when the index M converges to the reference value Mref when the battery 40 is continuously charged or discharged while the charge / discharge current Ib is constant. The absolute value of the input / output torque of the motor MG corresponding to the current value Iref is used.

  If it is determined in step S120 that the absolute value of the required torque T * is equal to or less than the reference torque Tref and the traveling load or braking load of the electric vehicle 20 (motor MG) is relatively small, the main ECU 50 displays the meter on the meter ECU 90. The command is set and the meter display command is transmitted to the meter ECU 90 (step S130), and this routine is temporarily terminated. The meter display command set in step S130 is a value corresponding to the vehicle speed V input to the current vehicle speed display unit 102 in step S100 while each segment 106 of the vehicle speed display unit 101 of the meter display device 100 emits blue light. Is displayed, and the pointer 105 points to a portion corresponding to the vehicle speed V. Then, the meter ECU 90 that has received the meter display command from the main ECU 50 controls the meter display device 100 so that information corresponding to the meter display command is displayed on the vehicle speed display unit 101.

  If it is determined in step S120 that the absolute value of the required torque T * exceeds the reference torque Tref, that is, the input limit Win and the output limit Wout are not limited based on the index M, and the electric vehicle When the traveling load or braking load of 20 (motor MG) is relatively large, the main ECU 50 sets a recommended vehicle speed Vrcm recommended for traveling of the electric vehicle 20 based on the road surface gradient θ input in step S100 (step S100). S140). In step S140, for example, the main ECU 50 converges the index M to the reference value Mref (does not exceed the reference value Mref) when traveling on a road having a road surface gradient θ with a torque corresponding to a current value equal to or less than the current value Iref. The obtained vehicle speed is set as the recommended vehicle speed Vrcm. In the present embodiment, the relationship between the road surface gradient θ and the recommended vehicle speed Vrcm when the input limit Win and the output limit Wout are not limited based on the index M is determined in advance as the first recommended vehicle speed setting map. In step S140, the recommended vehicle speed Vrcm corresponding to the road surface gradient θ is derived and set from the map.

  After setting the recommended vehicle speed Vrcm in step S140, the main ECU 50 sets a meter display command for the meter ECU 90, transmits the meter display command to the meter ECU 90 (step S150), and temporarily terminates this routine. The meter display command set in step S150 is set in step S140 from the segment 106 corresponding to the lowest vehicle speed (0 km / h) among the plurality of segments 106 of the vehicle speed display unit 101 of the meter display device 100, for example. Up to the segment 106 corresponding to the recommended vehicle speed Vrcm emits yellow light, a value corresponding to the vehicle speed V input in step S100 is displayed on the current vehicle speed display unit 102, and the pointer 105 points to the location corresponding to the vehicle speed V. The recommended vehicle speed display unit 103 displays a value that matches the recommended vehicle speed Vrcm set in step S140. Then, the meter ECU 90 that has received the meter display command from the main ECU 50 controls the meter display device 100 so that information corresponding to the meter display command is displayed on the vehicle speed display unit 101.

  Thus, even when the input limit Win and the output limit Wout are not limited based on the index M, the absolute value of the required torque T * exceeds the reference torque Tref, and the electric vehicle 20 (motor MG) When the travel load or braking load of the vehicle is relatively large, the travel state corresponding to the required torque T *, that is, the travel state requested by the driver, is continued as it is by causing the segment 106 of the vehicle speed display unit 101 to emit yellow light. Then, it is possible to notify the driver that the battery ECU 45 is likely to start limiting the input limit Win and the output limit Wout based on the index M in the future. In addition, by displaying a value that matches the recommended vehicle speed Vrcm set in step S140 on the recommended vehicle speed display unit 103, the original performance of the vehicle is maintained so that the input limit Wout and the output limit Wout are not limited. The recommended vehicle speed Vrcm to be obtained can be notified to the driver.

  On the other hand, when it is determined in step S110 that the charge / discharge restriction flag Flim is 1 and the input restriction Win and the output restriction Wout are restricted based on the index M, the main ECU 50 determines the road surface input in step S100. The recommended vehicle speed Vrcm corresponding to the gradient θ is set, and the maximum vehicle speed Vmax of the electric vehicle 20 is set based on the road surface gradient θ and the output limit Wout input in step S100 (step S160). In step S160, the main ECU 50 sets, for example, the recommended vehicle speed Vrcm as the vehicle speed obtained when the vehicle travels on a road having a road surface gradient θ with a torque corresponding to the current value that causes the index M to converge to the above-described limit release threshold. The vehicle speed obtained when the vehicle MG travels on the road with the road surface gradient θ by outputting torque from the motor MG within the range of the output limit Wout limited based on the index M is set as the maximum vehicle speed Vmax. In the present embodiment, the relationship between the road surface gradient θ and the recommended vehicle speed Vrcm when the input limit Win and the output limit Wout are limited based on the index M is determined in advance as the second recommended vehicle speed setting map, and the main ECU 50 In step S160, the recommended vehicle speed Vrcm corresponding to the road surface gradient θ is derived and set from the map. Further, the relationship between the road surface gradient θ and the output limit Wout and the maximum vehicle speed Vmax is determined in advance as a maximum vehicle speed setting map and stored in the ROM of the main ECU 50. In step S160, the road surface gradient θ and the output limit are calculated from the map. A maximum vehicle speed Vmax corresponding to Wout is derived and set.

  After setting the recommended vehicle speed Vrcm and the maximum vehicle speed Vmax in step S160, the main ECU 50 sets a meter display command for the meter ECU 90 and transmits the meter display command to the meter ECU 90 (step S170). End once. The meter display command set in step S170 is set in step S160 from the segment 106 corresponding to the lowest vehicle speed (0 km / h) among the plurality of segments 106 of the vehicle speed display unit 101 of the meter display device 100, for example. The segment 106 corresponding to the recommended vehicle speed Vrcm emits yellow light, the segment 106 corresponding to the maximum vehicle speed Vmax set in step S160 emits red light, and the vehicle speed V input to the current vehicle speed display unit 102 in step S100 is displayed. Is displayed, the pointer 105 indicates a position corresponding to the vehicle speed V, the recommended vehicle speed display unit 103 displays a value that matches the recommended vehicle speed Vrcm set in step S160, and the maximum vehicle speed display unit. 104 is a value that matches the recommended vehicle speed Vmax set in step S160. It is intended to be. The meter ECU 90 that has received the meter display command from the main ECU 50 controls the meter display device 100 so that information corresponding to the meter display command is displayed on the vehicle speed display unit 101.

  In this way, when the input limit Win and the output limit Wout are limited based on the index M, the battery ECU 45 inputs the segment 106 of the vehicle speed display unit 101 based on the index M by emitting light in yellow and red. It is possible to notify the driver that the limit Win and the output limit Wout are limited, and to suppress the occurrence of an uncomfortable feeling. Further, a recommended vehicle speed Vrcm that enables the restriction of the input limit Win and the output limit Wout to be released by lowering the index M calculated according to the equation (1) including the square value of the charge / discharge current of the battery 40 as a term, The maximum vehicle speed Vmax allowed at that time can be notified to the driver, and the execution of driving according to the situation can be supported.

  As described above, in the electric vehicle 20 according to the present embodiment, the battery ECU 45 causes the electric vehicle 20 to have a value equal to or less than the reference value Mref according to the above formula (1) including the square value of the charge / discharge current of the battery 40 as a term. When an index M indicating that an electronic component such as the mounted inverter 30 is protected is calculated, and when the calculated index M exceeds the reference value Mref, the input limit Win and the output limit Wout of the battery 40 are Charging power or discharging power is limited to be small. When the travel state corresponding to the requested torque T *, that is, the travel state requested by the driver, is a state in which there is a high possibility that the restriction of the input limit Win and the output limit Wout is started by the battery ECU 45 ( The yellow light emission of the segment 106 and the recommended vehicle speed Vrcm are notified to the driver via the meter display device 100 (steps S140 and S150). Further, while the input restriction Win and the output restriction Wout are restricted by the battery ECU 45, the fact (yellow and red emission of the segment 106), the recommended vehicle speed Vrcm, and the maximum vehicle speed Vmax are notified to the driver.

  Thus, when the battery ECU 45 is in a state where there is a high possibility that the restriction of the input restriction Win and the output restriction Wout is started, the restriction of the input restriction Win and the output restriction Wout is started for the driver in the future. In addition to notifying that there is a possibility, it is possible to notify the recommended vehicle speed Vrcm that can maintain the original performance of the vehicle by preventing the input restriction Wout and the output restriction Wout from being restricted. In addition, while the input restriction Win and the output restriction Wout are restricted, an expression that includes the square value of the charge / discharge current of the battery 40 as a term while notifying the driver of that fact and suppressing the occurrence of a sense of incongruity ( 1) Notifying the driver of the recommended vehicle speed Vrcm that allows the restriction of the input limit Win and the output limit Wout to be released by lowering the index M calculated according to 1), and further the maximum vehicle speed Vmax allowed at that time, It is possible to support the execution of driving according to the situation. As a result, it is possible to protect electronic components mounted on the electric vehicle 20 by restricting charging / discharging of the battery 40 while suppressing deterioration in drivability.

  The embodiments of the present invention have been described so far as the electric vehicle according to the present invention is an electric vehicle including only the motor MG as a generation source of traveling power. However, the electric vehicle according to the present invention is not limited to the motor. Thus, it may be configured as a one-motor type or two-motor type hybrid vehicle including the internal combustion engine as a power source for traveling. In this case, the electric vehicle according to the present invention may be configured as a so-called plug-in hybrid vehicle.

  Here, the correspondence between the main elements of the above embodiment and the main elements of the invention described in the column of means for solving the problems will be described. That is, in the above embodiment, the electric vehicle 20 including the motor MG that is an electric motor that can output the driving power and the battery 40 as a power storage device that can exchange electric power with the motor MG corresponds to an “electric vehicle”. An index indicating that the electronic component mounted on the electric vehicle 20 is protected when it is equal to or less than a predetermined reference value Mref according to the equation (1) including the square value of the charge / discharge current Ib of the battery 40 as a term. The battery ECU 45 that calculates M corresponds to “index calculation means”, and when the index M exceeds the reference value Mref, the battery ECU 45 that limits the input limit Win and the output limit Wout of the battery 40 The combination of the main ECU 50, the meter ECU 90, and the meter display device 100 corresponds to the “notification unit”. .

  However, the correspondence between the main elements of the above embodiment and the main elements of the invention described in the column of means for solving the problem is described in the column of means for solving the problem by the embodiment. Since the embodiment for carrying out the invention is an embodiment for specifically explaining the invention, the elements of the invention described in the column of means for solving the problems are not limited. That is, the above embodiment is merely a specific form of the invention described in the section for solving the problem, and the interpretation of the invention described in the section for solving the problem is This should be done based on the description in the column.

  Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and it goes without saying that various modifications can be made without departing from the scope of the present invention. .

  The present invention can be used in the manufacturing industry of electric vehicles.

  20 electric vehicle, 22 drive shaft, 24 differential gear, 30 inverter, 31 rotational position detection sensor, 35 boost converter, 40 battery, 45 battery electronic control unit (battery ECU), 50 main electronic control unit (main ECU), 51 Shift lever, 52 Shift range sensor, 53 Accelerator pedal, 54 Accelerator pedal position sensor, 55 Brake pedal, 56 Brake pedal stroke sensor, 57 Vehicle speed sensor, 58 Gradient sensor, 60 Brake electronic control unit (brake ECU), 80 Ignition switch 90 Meter electronic control unit (meter ECU) 100 Meter display device, 101 Vehicle speed display section, 102 Current vehicle speed display section, 103 Recommended vehicle speed display section, 104 Maximum vehicle speed display section, 1 5 guidelines, 106 segments, MG motor.

Claims (1)

In an electric vehicle including an electric motor capable of outputting driving power and a power storage device capable of exchanging electric power with the electric motor,
An index indicating that an electronic component mounted on the electric vehicle is protected when it is equal to or less than a predetermined reference value is larger as the square value is larger based on the square value of the charge / discharge current of the power storage device. And an index calculation means for calculating so that the smaller the smaller,
Charge / discharge allowable power limiting means for limiting charge allowable power and discharge allowable power of the power storage device when the index calculated by the index calculation means exceeds the reference value;
When the driving state requested by the driver is a state in which there is a high possibility that the charging / discharging allowable power limiting means will start limiting the charging allowable power and discharging allowable power, the driver and the recommended vehicle speed are indicated. And notifying means for notifying the driver of the recommended vehicle speed and the maximum vehicle speed while the allowable charging power and the allowable discharging power are limited by the allowable charging / discharging power limiting means,
An electric vehicle comprising:

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