JP2012222876A - Travelable distance calculation apparatus for electric vehicle and the electric vehicle provided with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a travelable distance calculation apparatus for an electric vehicle in which the calculation accuracy of a travelable distance is enhanced, and to provide an electric vehicle provided with the same.SOLUTION: The electric vehicle includes a power storage device 10, a vehicle driving part (inverter 20, a motor 30) receiving power from the power storage device 10 and generating a traveling driving force and an air conditioner 64. The travelable distance calculation apparatus includes a first learning part learning the power consumption of a basic portion of the electric vehicle including the vehicle driving part, a second learning part learning the power consumption of the air conditioner, a third leaning part learning a traveling distance, and a calculating part calculating the travelable distance of the electric vehicle according to learning results of the first to third learning parts and the residual power storage amount of the power storage device.

Description

  The present invention relates to a travelable distance calculation device for an electric vehicle and an electric vehicle including the same.

  In recent years, electric vehicles have attracted attention as vehicles that do not emit carbon dioxide. From the same point of view, plug-in hybrid vehicles that can be charged from the outside have also been developed. In such a vehicle, there is a great need to travel only with charged electric power or to travel with only charged electric power. Therefore, it is necessary for the user to always drive while being aware of the remaining amount of the battery. This is because there are still limited places where vehicles can be charged.

  Japanese Patent Laid-Open No. 6-167551 (Patent Document 1) detects a discharge voltage value and a discharge current value of a battery at the time of discharging, and subtracts a power consumption calculated based on them from the remaining battery level at that time. A vehicle that displays the result as the current remaining battery level is disclosed. According to this vehicle, the remaining battery level corresponding to the actual travelable distance of the electric vehicle can be accurately displayed.

JP-A-6-167551 JP 2010-179749 A

  Charging facilities for electric vehicles are overwhelmingly less than the number of gas stations in the current mainstream gasoline vehicles. Therefore, once charging is performed, there is a possibility that the next charging facility cannot be reached and may be stuck. Therefore, it is necessary to accurately grasp the remaining power storage amount of the power storage device. However, even if the remaining power storage amount is accurately displayed, it is difficult for the driver to immediately know how much the driving distance the amount corresponds to.

  In particular, the electric vehicle cannot run when the remaining power storage amount of the power storage device is exhausted. For this reason, the information on the distance that can be traveled by the remaining power storage amount is very important for the driver, and it is required to display this accurately.

  Such a travelable distance varies greatly depending on the conditions of the road on which the driver often travels (for example, there are many slopes, the car travels on a highway, etc.). The frequency of using auxiliary equipment (such as an air conditioner) varies depending on the driver. For this reason, it is preferable to learn about these. In particular, an electric vehicle does not have an internal combustion engine, and the power consumption of the air conditioner increases. Therefore, how to learn the power consumption of an air conditioner is important.

  An object of the present invention is to provide a travelable distance calculation device for an electric vehicle with improved calculation accuracy of a travelable distance and an electric vehicle including the same.

  In summary, the invention is a travelable distance calculation device for an electric vehicle, the electric vehicle including a power storage device, a vehicle drive unit that receives power from the power storage device and generates a travel driving force, and an air conditioner, The travelable distance calculating device includes a first learning unit that learns power consumption of a basic part of an electric vehicle including a vehicle drive unit, a second learning unit that learns power consumption of an air conditioner, and third learning that learns a travel distance. And a calculation unit that calculates the travelable distance of the electric vehicle according to the learning result of the first to third learning units and the remaining power storage amount of the power storage device.

  Preferably, the calculation unit determines whether to consider the learning result in the second learning unit based on the current operating state of the air conditioner and calculates the travelable distance.

  More preferably, a 1st learning part learns the value which deducted the power consumption of a cold countermeasure device from the power consumption of an electrical storage apparatus as power consumption of a basic part. The cold countermeasure device includes an air conditioner and glass with a melting ice or anti-fogging function.

Preferably, the electric vehicle is an electric vehicle.
In another aspect, the present invention is an electric vehicle including any one of the above-described travelable distance calculation devices.

  According to the present invention, since the travelable distance is calculated with high accuracy, planned driving can be realized. For this reason, it is possible to reduce the situation in which the battery cannot be reached once after being charged.

1 is an overall block diagram of an electric vehicle according to an embodiment of the present invention. It is a functional block diagram of ECU50 shown in FIG. It is a flowchart for demonstrating the integration process of the energy consumption performed by ECU50. 5 is a flowchart for illustrating a travelable distance calculation process executed by an ECU 50.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.

FIG. 1 is an overall block diagram of an electric vehicle according to an embodiment of the present invention.
Referring to FIG. 1, electrically powered vehicle 100 includes a power storage device 10, an inverter 20, a motor generator 30, and drive wheels 35. The electric vehicle 100 further includes a voltage sensor 42, a current sensor 44, a temperature sensor 46, a wheel speed sensor 37, an electronic control device (hereinafter referred to as “ECU: Electric Control Unit”) 50, and a display device 60. Is provided.

  The power storage device 10 is a direct current power source that stores electric power for running the vehicle. The power storage device 10 is configured by a secondary battery such as nickel hydride or lithium ion, for example. The power storage device 10 is charged by a power source outside the vehicle using a charger (not shown). In addition, the electric power generated by the motor generator 30 is charged to the power storage device 10 via the inverter 20 also when the electric vehicle 100 is braked or when the acceleration on the down slope is reduced.

  The power storage device 10 outputs the stored power to the inverter 20. Inverter 20 converts DC power supplied from power storage device 10 into three-phase AC based on signal PWI from ECU 50 and outputs the same to motor generator 30 to drive motor generator 30.

  At the time of braking of electrically powered vehicle 100, inverter 20 converts the three-phase AC power generated by motor generator 30 into DC based on signal PWI, and outputs the converted power to power storage device 10. Inverter 20 is configured by a three-phase PWM inverter including switching elements for three phases, for example.

  The motor generator 30 is a motor generator capable of a power running operation and a regenerative operation. The motor generator 30 is configured by, for example, a three-phase AC synchronous motor generator in which a permanent magnet is embedded in a rotor. The motor generator 30 is driven by the inverter 20 and generates driving torque for driving to drive the driving wheels 35. In addition, when the electric vehicle 100 is braked, the motor generator 30 receives the kinetic energy of the electric vehicle 100 from the drive wheels 35 and generates electric power.

  Voltage sensor 42 detects voltage VB of power storage device 10 and outputs the detected value to ECU 50. Current sensor 44 detects current IB input to and output from power storage device 10 and outputs the detected value to ECU 50. Temperature sensor 46 detects temperature TB of power storage device 10 and outputs the detected value to ECU 50. The wheel speed sensor 37 outputs a pulse generated with the rotation angle of the drive wheel 35. The ECU 50 can count the number of pulses to calculate the travel distance L and the vehicle speed. Note that the moving distance and the vehicle speed may be obtained by detecting the rotational speed of the motor generator 30 instead of the wheel speed sensor 37.

  ECU 50 receives detected values of voltage VB, current IB, and temperature TB from voltage sensor 42, current sensor 44, and temperature sensor 46, respectively. Then, ECU 50 generates a PWM signal for driving inverter 20 and outputs the generated PWM signal to inverter 20 as signal PWI.

  Further, ECU 50 calculates the SOC (State Of Charge: also referred to as state of charge, remaining capacity, and amount of stored electricity) of power storage device 10 based on the detected values of voltage VB and current IB. As a calculation method of the SOC, various known methods such as a method of calculating using the relationship between the open circuit voltage (OCV) of the power storage device 10 and the SOC and a method of calculating using the integrated value of the current IB are used. be able to.

  Based on signal DISP from ECU 50, display device 60 displays information relating to the distance that can be traveled using the current amount of electricity stored in power storage device 10 when the vehicle is started.

  Vehicle 100 includes an air conditioner 64, a DC / DC converter 62, an auxiliary device 68, and an EHW (Electrically Heated Window) 66 as devices that receive power supply from power storage device 10. The EHW 66 is a glass with melted ice or anti-fogging function for an automobile windshield. A transparent heating element is provided on the surface of this glass, and when it is energized, it melts ice and functions to prevent fogging when cold.

  The ECU 50 receives power consumption Pac information from the air conditioner 64. The ECU 50 receives a signal EHWON indicating an on / off state from the EHW 66. ECU 50 calculates power consumption Pbatt in power storage device 10 from current IB and voltage VB. The ECU 50 learns air conditioner power consumption and travel power consumption at regular intervals (for example, one minute) based on the power consumption Pbatt, the power consumption Pac, and the signal EHWON.

  In FIG. 1, an electric vehicle is shown as an example of a vehicle. However, the travelable distance calculation device disclosed in the present embodiment may be a power storage device such as a plug-in hybrid vehicle as long as it can travel independently by a motor. The present invention can also be applied to a vehicle including an internal combustion engine in addition to the device 10 and the motor generator 30.

  FIG. 2 is a functional block diagram of ECU 50 shown in FIG. FIG. 2 shows only the configuration relating to the travelable distance calculation of the ECU 50 of FIG. The ECU 50 can be realized by software or hardware.

  Referring to FIG. 2, ECU 50 receives a multiplier 102 that calculates power Pbatt by multiplying current IB flowing through power storage device 10 and voltage VB of power storage device 10, and receives signal EHWON indicating on / off of EHW at EHW 66. It includes a conversion unit 104 that converts power to consumed power, and a calculation unit 106 that subtracts the power consumed by the EHW and the power consumed by the air conditioner 64 from the power consumption Pbatt of the power storage device 10 to obtain the travel power consumption.

  ECU 50 further includes an integration unit 107 that integrates each power consumption at regular intervals. Integration unit 107 includes an integration unit 110 that integrates the travel power consumption calculated by calculation unit 106 and an integration unit 112 that integrates air conditioner power consumption PAC.

  ECU 50 further includes a learning unit 113 that calculates a learning value during a certain period (for example, 1 minute) longer than the integration time of integration unit 107.

  The learning unit 113 receives the output of the integrating unit 110 for a certain period and outputs the travel consumption energy Erun which is a learning value, and receives the output of the integrating unit 112 and calculates the learning value for each predetermined period. It further includes a learning unit 116 and a learning unit 118 that learns the travel distance L at regular intervals. Each learning unit calculates, for example, an average value for a certain period (for example, 1 minute) and uses it as a learning value.

  ECU 50 includes a calculation unit 119 that calculates the travelable distance of vehicle 100 according to the learning results of learning units 114, 116, and 118 and the remaining power storage amount SOC.

  Calculation unit 119 includes a selector 120, an addition unit 122, a power consumption calculation unit 124, and a travelable distance calculation unit 126.

  The selector 120 switches between the output of the learning unit 116 and 0 in response to the on / off switch signal AC-ON of the air conditioner. The adding unit 122 adds the travel consumption energy Erun output from the learning unit 114, the EHW consumption energy Eehw output from the conversion unit 104, and the air-conditioner consumption energy Eac output from the selector 120, to obtain a total consumption energy Etot. Is output. The power consumption calculation unit 124 outputs the power consumption Econs based on the energy consumption Etot and the distance learning value Ls output from the learning unit 118. The travelable distance calculation unit 126 outputs the travelable distance RL according to the power consumption Econs and the remaining power storage amount SOC.

  Here, the electricity consumption indicates the meaning corresponding to the fuel consumption in the vehicle. In this specification, the electric power consumption (km / Wh) indicates the distance (km) that can be traveled per unit energy (Wh). In addition, since the electricity bill is a term that has not been unified yet, the above reciprocal may be referred to as the electricity bill.

  The travelable distance calculation unit 126 transmits the travelable distance RL to the display device 60. The travelable distance RL includes travel energy consumption Erun, EHW energy consumption Eehw, air conditioner energy consumption Eac, distance learning value Ls, and SOC acquired in the processing cycle of the ECU 50, which are updated at regular intervals (for example, 1 minute). Has been determined based on.

  FIG. 3 is a flowchart for explaining the energy consumption integration process executed by the ECU 50. The process of this flowchart is called from the main routine and executed at regular time intervals or whenever a predetermined condition is satisfied.

  Referring to FIGS. 2 and 3, when the process is started, the power consumption of EHW is calculated in step S1. This processing is performed by the conversion unit 104 in FIG. The EHW 66 in FIG. 1 transmits only an on / off signal to the ECU 50 by communication. However, the power consumption at the time of ON is a constant value. For this reason, when the signal EHWON indicates the ON state, a predetermined value is calculated as the EHW power consumption. When the signal EHWON indicates the OFF state, the EHW power consumption is set to 0 kW. When the EHW is applied to several divided areas (for example, the right area and the left area), predetermined power corresponding to the area is set for each area in the state of the on / off switch for each area. What is necessary is just to determine whether it adds to power consumption.

  Subsequently, in step S2, energy of each parameter is calculated. As the parameters, air conditioner energy consumption, EHW energy consumption, and battery energy consumption are first calculated. The travel energy consumption is calculated by subtracting the air conditioner energy consumption and the EHW energy consumption from the battery energy consumption. This is because air-conditioner energy consumption and EHW energy consumption often fluctuate depending on the surrounding environment such as air temperature, and since it is an auxiliary load with a large amount of power, it is especially taken into account in order to accurately calculate the travelable distance. It is necessary. Note that it is preferable to set each energy consumption to a value obtained by multiplying the power consumption by the integration cycle time, because the energy consumption can be finally obtained by simply adding in the next integration.

  Subsequently, energy accumulation processing is performed in step S3. If the energy consumption of the air conditioner is greater than 0, the energy consumption of the air conditioner is integrated. As a result, the average value of the fluctuating air conditioner consumption energy is obtained. When the air-conditioner energy consumption is zero, the average value is also zero, so no particular integration is required. This processing is performed by the integrating unit 112 in FIG. In step S3, battery energy consumption is also integrated. Further, in step S3, traveling energy consumption is also integrated. Thereby, the average value of travel energy consumption is calculated | required. Note that EHW is not integrated here because it is not necessary to obtain an average value because power consumption is constant.

  When the process of step S3 ends, the process proceeds to step S4. In step S4, it is determined whether or not the current time is the timing for updating the learning in the learning units 114, 116, and 118. This learning update timing comes every certain time (for example, 1 minute).

  If it is detected in step S4 that it is the learning update timing, the process proceeds to step S5. If it is not yet the learning update timing, the process proceeds to step S12.

  In step S5, the ECU 50 determines whether or not the air conditioner 64 has been operated. If it is determined in step S5 that the air conditioner 64 is operating, the process proceeds to step S6, and the ECU 50 calculates a learning value for the air conditioner power consumption. In FIG. 2, it is determined whether or not the air conditioner is operating based on the signal AC-ON.

  In step S6, a learning value for the power consumption of the air conditioner is calculated. This process is realized by the learning unit 116 and the selector 120 in FIG.

  Subsequently, in step S7, the power consumption for learning permission is calculated. The power consumption for learning permission is, for example, a learning value that is not suitable for calculating the travelable distance if learning is performed when the vehicle is in a normal driving state such as when the vehicle is involved in a traffic jam. turn into. Further, in a case where the downhill continues, if the learning is performed, the travelable distance is calculated on the assumption that the same downhill continues. For this reason, it is judged whether learning is performed based on the current values of the power consumption and the travel distance.

  In step S <b> 7, the ECU 50 calculates a value obtained by dividing the travel energy consumption by the difference in distance as the learning permission power consumption. In step S8, the condition that the travel distance (difference between the previous value and the current value) is greater than the threshold value X (km) and the power consumption is greater than or equal to the threshold value Y and less than or equal to the threshold value Z is satisfied. Determine whether or not. If the learning condition is satisfied in step S8, the processes in steps S9 and S10 are executed. On the other hand, if the learning condition in step S8 is not satisfied, the processing in step S9 and step S10 is not executed, and the process proceeds to step S11.

  In step S9, the learning value of the travel power consumption is calculated. This processing is executed by the learning unit 114 in FIG. Thereafter, in step S10, the learning value of the travel distance is calculated. This processing is executed by the learning unit 118 in FIG. In step S11, the counter that counts the timing for updating the learning value is cleared, the integrated value of each energy consumption is cleared, and the travel distance measured this time as the previous measurement value of the travel distance L is calculated. Is set. In step S12, the process returns to the main routine.

  FIG. 4 is a flowchart for explaining a travelable distance calculation process executed by the ECU 50.

  Referring to FIGS. 2 and 4, when the process is started, the travel energy calculated by learning unit 114 in FIG. 2 is set as the basic energy in step S21. In step S22, it is determined whether or not the air conditioner switch is on. Instead of this, it may be determined whether the air-conditioner power consumption Pac is greater than zero. If it is determined in step S22 that the air conditioner is in the ON state, the learning value of the air conditioner consumption energy is added to the basic energy in step S23.

  On the other hand, if it is determined in step S22 that the air conditioner is not on, the process proceeds to step S24 without executing the process in step S23. In step S24, it is determined whether or not the EHW is on. This may be determined based on the signal EHWON, or may be determined based on whether or not the EHW consumption energy, which is the output of the conversion unit 104 in FIG.

  If it is determined in step S24 that the EHW is on, the process of step S25 is executed. In step S25, processing for adding EHW consumption energy to basic energy is performed. On the other hand, if it is determined in step S24 that the EHW is not in the ON state, the process proceeds to step S26 without performing the process in step S25.

  In step S26, the electricity cost is determined by dividing the distance by the energy. The distance learning value Ls learned by the learning unit 118 of FIG. 2 is used as this distance, and the total energy Etot that is the output of the adding unit 122 is used as the energy.

  In step S27, the travelable distance is calculated. The travelable distance can be obtained by calculating (current SOC−lower limit SOC) × battery capacity × voltage × electricity consumption. In step S26, the power consumption is obtained by dividing the distance by the energy, but the reciprocal value may be referred to as the power consumption. In this case, in step S27, a process of dividing by the power cost is performed instead of the power cost.

  Following the process in step S27, the annealing process is performed in step S28. The annealing process is a process that causes a change to occur slowly by limiting the changeable width in order to give a sense of incongruity when the obtained travelable distance changes too rapidly. When the annealing process in step S28 ends, control is returned to the main routine in step S29.

  As described above, in the present embodiment, the power consumed for traveling in the electric vehicle, the power consumed for other than traveling (for example, the operation of an air conditioner, EHW, etc.) and the distance traveled are learned. Then, using these learned values, a power consumption and a travelable distance are calculated. By learning each parameter separately, it is possible to calculate an accurate travelable distance with respect to how the driver runs, the route that the driver travels, and the like. For example, when the air conditioner is turned off, the energy learning value for the air conditioner can be immediately subtracted from the learned value, and the travelable distance can be calculated and displayed. There is also an effect that can be done.

  Finally, referring to FIG. 1 again, the present embodiment will be summarized. Electric vehicle 100 includes a power storage device 10, a vehicle drive unit (inverter 20, motor generator 30) that receives electric power from power storage device 10 and generates a travel driving force, and an air conditioner 64. As shown in FIG. 2, the ECU 50 that operates as the travelable distance calculating device has a first learning unit 114 that learns the power consumption of the basic portion of the electric vehicle including the vehicle drive unit, and a second that learns the power consumption of the air conditioner 64. According to the learning unit 116, the third learning unit 118 that learns the travel distance L, the learning results of the first learning unit 114, the second learning unit 116, and the third learning unit 118, and the remaining storage amount SOC of the power storage device And a calculation unit 119 for calculating the travelable distance RL of the electric vehicle.

  Preferably, the calculation unit 119 determines whether to consider the learning result of the second learning unit 116 based on the current operating state of the air conditioner 64 and calculates the travelable distance RL.

  More preferably, the first learning unit 114 learns a value obtained by subtracting the power consumption of the cold countermeasure device from the power consumption of the power storage device 10 as the power consumption of the basic portion. The cold countermeasure device includes an air conditioner 64 and glass with melted ice or antifogging function (EHW).

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  DESCRIPTION OF SYMBOLS 10 Power storage device, 20 Inverter, 30 Motor generator, 35 Drive wheel, 37 Wheel speed sensor, 42 Voltage sensor, 44 Current sensor, 46 Temperature sensor, 60 Display apparatus, 62 DC / DC converter, 64 Air conditioner, 68 Auxiliary machine, 100 Electric vehicle, 102 multiplier, 104 conversion unit, 106, 119 calculation unit, 107, 110, 112 integration unit, 113 learning unit, 114 first learning unit, 116 second learning unit, 118 third learning unit, 120 selector, 122 adder, 124 power consumption calculator, 126 travelable distance calculator.

Claims (5)

A travelable distance calculation device for an electric vehicle,
The electric vehicle is
A power storage device;
A vehicle drive unit that receives electric power from the power storage device and generates a driving force;
Including air conditioner,
The travelable distance calculation device includes:
A first learning unit that learns power consumption of a basic part of the electric vehicle including the vehicle driving unit;
A second learning unit for learning the power consumption of the air conditioner;
A third learning unit for learning the mileage;
A travelable distance calculation device comprising: a calculation unit that calculates a travelable distance of the electric vehicle according to a learning result of the first to third learning units and a remaining power storage amount of the power storage device. The computing unit is
The travelable distance calculation device according to claim 1, wherein the travelable distance is calculated by determining whether or not to consider the learning result in the second learning unit based on a current operating state of the air conditioner. The first learning unit learns a value obtained by subtracting the power consumption of the cold countermeasure device from the power consumption of the power storage device as the power consumption of the basic portion,
The cold countermeasure device is
The air conditioner;
The travelable distance calculating device according to claim 2, comprising melted ice or glass with an antifogging function.   The travelable distance calculation device according to any one of claims 1 to 3, wherein the electric vehicle is an electric vehicle.   An electric vehicle comprising the travelable distance calculating device according to any one of claims 1 to 4.

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