JP2012240442A - Hybrid car - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an induced voltage value generated by a motor when a sufficient torque is obtained and the control of the motor is released, even when the shift position is in a neutral position. Provided is a hybrid vehicle capable of suppressing the increase in height.
SOLUTION: A hybrid vehicle 10 includes an electric motor 20, a battery 50, a generator 65, a CMU 52 that detects a voltage value of the battery 50, a battery ECU 60, and an induced voltage value of the electric motor 20 that is a voltage value of the battery 50. A motor ECU 73 that controls the electric motor 20 is provided so as to be as follows. When the control of the electric motor 20 by the motor ECU 73 is released, the hybrid vehicle 10 charges the battery 50 with the generator 65 so that the voltage value of the battery 50 is higher than the induced voltage value of the electric motor 20.
[Selection] Figure 1

Description

  The present invention relates to a hybrid vehicle including an electric motor that drives drive wheels and a generator that charges a battery.

  In a vehicle such as an electric vehicle or a hybrid vehicle that includes an electric motor that drives driving wheels, the electric motor generates an induced voltage. The value of the induced voltage generated by the electric motor increases in proportion to the rotational speed of the output shaft of the electric motor. In this type of vehicle, the inverter that supplies electric power to the electric motor performs control to prevent the induced voltage value generated by the electric motor during traveling of the vehicle from becoming larger than the voltage value of the battery.

  On the other hand, when the shift position is in the neutral position, power supply from the inverter to the electric motor is cut off. This makes it impossible to control the value of the induced voltage generated by the electric motor when the shift position is in the neutral position. For this reason, for example, if the shift position is set to the neutral position while the vehicle is traveling at high speed, the value of the induced voltage generated by the electric motor may exceed the voltage value of the battery.

  When the shift position is in the neutral position and the induced voltage value generated by the electric motor exceeds the battery voltage value, power is transferred from the inverter to the electric motor when the shift position is changed from the neutral position to the drive position. In a state in which the value of the induced voltage generated by the electric motor is larger than the battery voltage value.

  For this reason, even when the shift position is in a neutral state, the state in which electric power is supplied from the inverter to the electric motor is maintained, and the value of the induced voltage generated by the electric motor by the inverter does not become larger than the battery voltage. Control is performed (see, for example, Patent Document 1).

  However, in a state where the shift position is in the neutral position, there is a demand for cutting off the supply of electric power to the electric motor.

  For this reason, it has been proposed to devise the design of the electric motor. Specifically, the electric motor is designed so that the value of the induced voltage generated by the electric motor during traveling of the vehicle does not exceed the voltage value of the battery without control of the inverter. Here, the value of the induced voltage generated by the electric motor when the vehicle is traveling is the value of the induced voltage when the vehicle is traveling at the expected maximum speed.

JP-A-6-225402

  However, the electric motor designed so that the value of the induced voltage generated by the electric motor when the vehicle is traveling at the predicted maximum speed is smaller than the battery voltage value without the control of the inverter has a small torque.

  In the present invention, when a sufficient torque is obtained and the control of the motor is released, the value of the induced voltage generated by the motor becomes higher than the voltage of the battery even when the shift position is in the neutral position. It aims at providing the hybrid vehicle which can suppress this.

  The hybrid vehicle according to claim 1 includes an electric motor that drives a vehicle, a battery that supplies electric power to the electric motor, a generator that is driven by an engine mounted on the vehicle and charges the battery, and the battery. In the hybrid vehicle comprising: a battery voltage value detecting means for detecting the voltage value of the motor; and an electric motor control means for controlling the electric motor so that an induced voltage value of the electric motor is equal to or lower than the voltage value of the battery. When the control of the electric motor is released, the battery is charged by the generator to make the voltage value of the battery higher than the induced voltage value.

  The hybrid vehicle according to claim 2 further includes shift position detection means for detecting a position of a shift position of the vehicle according to claim 1, and when the shift position detection means detects that the position is a neutral position. The control by the motor control means is released.

  A hybrid vehicle according to a third aspect further includes voltage difference calculation means for calculating a difference between the voltage value and the induced voltage value according to the first or second aspect, wherein the induced voltage value and the voltage value are The voltage deficiency that is the difference between the two is charged by the generator.

  A hybrid vehicle according to a fourth aspect of the present invention is the hybrid vehicle according to any one of the first to third aspects, further comprising a rotational speed detection means for detecting a rotational speed of the electric motor, wherein the induced voltage value is: It is calculated based on the rotation speed of the electric motor.

  According to the present invention, when a sufficient torque is obtained and the control of the electric motor is released, the induced voltage value generated by the electric motor is greater than the voltage of the battery even when the shift position is in the neutral position. It is possible to provide a hybrid vehicle that can suppress the increase.

1 is a schematic diagram showing a hybrid vehicle according to an embodiment of the present invention. The block diagram which shows a part of structure of main ECU shown by FIG. The flowchart which shows operation | movement of the motor induced voltage value calculating part shown by FIG. The graph which shows the relationship between the voltage value of the battery shown by FIG. 1, and the induced voltage value which an electric motor generate | occur | produces. The graph which shows the value of the induced voltage which an electric motor generate | occur | produces with an example of driving | running | working of the hybrid vehicle shown by FIG. 1, and the voltage value of a battery. The flowchart which shows operation | movement of the generator output value calculating part shown by FIG. The flowchart which shows operation | movement of main ECU shown by FIG.

  A hybrid vehicle according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a schematic diagram showing a hybrid vehicle 10 which is an example of a hybrid vehicle. As shown in FIG. 1, the hybrid vehicle 10 includes an electric motor 20, an engine 25, an engine ECU 30, a transmission device 40, a battery 50, a battery ECU 60, a generator 65, an inverter 70, and a shift position sensor. 75, an accelerator sensor 85, and a main ECU 90 are provided. ECU has shown Electric Control Unit.

  The electric motor 20 is a three-phase AC electric motor as an example. The electric motor 20 is an example of an electric motor referred to in the present invention. The electric motor 20 is driven by three-phase AC power supplied from an inverter 70 described later. When the electric motor 20 is driven, the output shaft 21 of the electric motor 20 rotates.

  The electric motor 20 is provided with a motor rotation speed detection sensor (rotation speed detection means) 22. The motor rotation speed detection sensor 22 detects the rotation speed of the output shaft 21 of the electric motor 20. In this embodiment, the unit of the number of revolutions is rpm (revolutions per minute) as an example.

  The drive of the engine 25 is controlled by the engine ECU 30. As an example, the engine 25 is a reciprocating engine that uses gasoline as fuel. When the engine 25 is driven, the output shaft 26 rotates.

  The transmission device 40 transmits the rotation of the output shaft 21 of the electric motor 20 and the rotation of the output shaft 26 of the engine 25 to the front wheels 11 that are drive wheels. The hybrid vehicle 10 includes a pair of front wheels 11 and a pair of rear wheels 12.

  The hybrid vehicle 10 is a series-parallel hybrid vehicle. For this reason, the hybrid vehicle 10 is generated by an EV (Electric Vehicle) travel mode in which the vehicle travels only by the driving force of the electric motor 20 driven by electric power supplied from the battery 50 described later, and a generator 65 described later. A series travel mode in which the vehicle travels only by the driving force of the electric motor 20 driven by the electric power, and a parallel travel mode in which the vehicle travels by the driving force of both the electric motor 20 and the engine 25.

  The transmission device 40 has a configuration for enabling an EV traveling mode, a series traveling mode, and a parallel traveling mode. As an example, the transmission device 40 is provided on the output shaft 26 of the engine 25 and rotates integrally with the output shaft 26. The transmission device 40 is provided on the output shaft 21 of the electric motor 20 and integrated with the output shaft 21. A second gear 42 that rotates, a third gear 43 that meshes with the first gear 41, a shaft portion 44 that integrally connects the third gear 43 and the second gear 42, and a shaft portion 44. And a fourth gear 46 which is provided on the axle 13 which meshes with the second gear 42 and rotates integrally with the left and right front wheels and which rotates integrally with the axle 13.

  When the clutch device 45 is turned on, the pair of clutch plates 45a and 45b of the clutch device 45 are pressed against each other. When the clutch device 45 is in the on state, the rotation of the third gear 43 is transmitted to the second gear 42. The clutch device 45 is in an off state when the pair of clutch plates 45a and 46b are separated from each other.

  The structure of the transmission device 40 is not limited to the above. The transmission device 40 only needs to have a configuration that enables the travel mode set in the hybrid vehicle 10.

  The battery 50 is a rechargeable secondary battery. The battery 50 is an example of a battery referred to in the present invention. The battery 50 includes a plurality of battery cells 51. The plurality of battery cells 51 are electrically connected in series. Each battery cell 51 is provided with a CMU (Cell Monitor Unit) 52. The CMU 52 detects the state of the battery in the battery cell 51. The battery state of the battery cell 51 includes the voltage value of the battery cell 51. In FIG. 1, some of the plurality of batteries 50 are shown.

  The battery ECU 60 receives information detected by each CMU 52. The battery ECU 60 detects the state of the battery 50 based on information transmitted from each CMU 52. The state of the battery 50 includes the voltage value of the battery 50 and the charging rate of the battery 50. Thus, in this embodiment, the voltage value of the battery 50 is detected by each CUM 52 and the battery ECU 60.

  The generator 65 generates AC power by rotating the rotating shaft 66. The generator 65 is an example of a generator referred to in the present invention. The transmission device 40 has a function of transmitting the rotation of the output shaft 26 of the engine 25 to the rotation shaft 66 of the generator 65. Specifically, the transmission device 40 includes a fifth gear 47 that meshes with a first gear 41 provided on the output shaft 26 of the engine 25. The fifth gear 47 is provided on the rotating shaft 66 of the generator 65 and rotates integrally with the rotating shaft 66. The rotation of the output shaft 26 of the engine 25 is transmitted to the rotation shaft 66 of the generator 65 by the first and fifth gears 41 and 47.

  The inverter 70 includes a motor conversion circuit 71, a generator conversion circuit 72, a motor ECU 73, and a generator ECU 74.

  As an example, the motor conversion circuit 71 includes a switching element such as an IGBT and a diode. The DC power supplied from the battery 50 is converted into AC power by the motor conversion circuit and supplied to the electric motor 20. The motor ECU 73 controls the electric power supplied to the electric motor 20 by controlling the operation of the motor conversion circuit 71. Specifically, the motor ECU 73 controls the operation of the switching element of the motor conversion circuit 71.

  As an example, the generator conversion circuit 72 includes a switching element such as an IGBT and a diode. The generator conversion circuit 72 converts the AC power generated by the generator 65 into DC power and supplies it to the battery 50 to charge the battery 50. The generator ECU 74 controls the power supplied to the battery 50 by controlling the operation of the generator conversion circuit 72. Specifically, the generator ECU 74 controls the operation of the switching element of the generator conversion circuit 72.

  A shift position sensor (shift position detection means) 75 detects the position of the shift lever 76. The range F1 is enlarged and shown in FIG. The range F <b> 1 is the vicinity of the shift lever 76 and the shift lever 76. As shown in the range F1, in this embodiment, as an example, the shift lever 76 is located at any one of the parking position P1, the reverse position P2, the neutral position P3, and the drive position P4. In FIG. 1, the letter P is written at the parking position P1. The letter R is written in the reverse position P2. In the neutral position P3, the letter N is written. The letter D is written in the drive position P4.

  The shift position sensor 75 detects the position of the shift lever 76. In FIG. 1, the shift lever 76 is in the parking position P1. The accelerator sensor 85 detects the amount of depression of the accelerator pedal 15.

  The main ECU 90 performs various controls of the hybrid vehicle 10. As an example of the control, the main ECU 90 controls the traveling of the hybrid vehicle 10 and the operation of the generator 65. For this reason, the main ECU 90 is connected to the accelerator sensor 85, the motor rotation number detection sensor (rotation number detection means) 22, the shift position sensor 75, the battery ECU 60, the motor ECU 73, the engine ECU 30, and the generator ECU 74. Has been.

  The accelerator sensor 85 transmits the detection result to the main ECU 90. The motor rotation speed detection sensor 22 transmits the detection result to the main ECU 90. The shift position sensor 75 transmits the detection result to the main ECU 90. Battery ECU 60 transmits information on battery 50 to main ECU 90. The information on the battery 50 includes information on the voltage value and the charging rate of the battery 50.

  The motor ECU 73 is controlled by the main ECU 90. Specifically, the main ECU 90 calculates the vehicle speed of the hybrid vehicle 10 based on information from the motor rotation speed detection sensor 22. Further, the main ECU 90 obtains the depression amount of the accelerator pedal 15 based on the information received from the accelerator sensor 85. The main ECU 90 selects the travel mode of the hybrid vehicle 10 according to the position of the shift lever 76, the depression amount of the accelerator pedal 15, and the vehicle speed, and controls the motor ECU 73 in accordance with the selected travel mode to control the electric motor. The motor ECU 73 and the engine ECU 30 are controlled to drive the engine 20 and the engine 25. As means for detecting the vehicle speed of the hybrid vehicle 10, means other than the means using the motor rotation speed detection sensor 22 may be used.

  The generator ECU 74 is controlled by the main ECU 90. The main ECU 90 controls the generator ECU 74, the engine ECU 30, and the battery ECU 60 in order to charge the battery 50 when the charging rate of the battery 50 falls below a predetermined value that is set in advance. As a result, the battery 50 is charged.

  Further, as the operation of the main ECU 90, various ECUs are controlled so that the value of the induced voltage generated by the electric motor 20 does not exceed the first predetermined voltage value V4. This control will be specifically described. The first predetermined voltage value V4 is a value obtained by subtracting ΔV1 from the voltage value V2 of the battery 50. Above the first predetermined voltage value also includes the first predetermined voltage value.

  First, control in a state where the shift lever 76 is at the drive position P4 will be described. FIG. 2 is a block diagram showing a part of the configuration of the main ECU 90. As shown in FIG. 2, the main ECU 90 includes a shift position determination unit 91 and a motor induced voltage value calculation unit so that the value of the induced voltage generated by the electric motor 20 does not exceed the first predetermined voltage value. 92, an undervoltage value calculation unit (voltage difference calculation means) 93, a generator output value calculation unit 94, and a power generation control unit 95.

  The shift position determination unit 91 determines the position of the shift lever 76 based on information transmitted from the shift position sensor 75, and determines whether or not the shift position is the neutral position P3. The motor induced voltage value calculation unit 92 calculates an induced voltage value generated by the electric motor 20 based on the rotation speed information of the output shaft 21 of the electric motor 20. The rotational speed information of the output shaft 21 of the electric motor 20 is obtained from the motor rotational speed detection sensor 22.

  The motor induced voltage value calculation unit 92 has a map M1. FIG. 3 is a flowchart showing the operation of the motor induced voltage value calculation unit 92. A map M1 is shown in the flowchart. As shown in FIG. 3, the map M <b> 1 shows the value of the induced voltage with respect to the rotation speed of the electric motor 20. The horizontal axis of the map M1 indicates the rotation speed of the output shaft 21 of the electric motor 20. The value of the horizontal axis increases as it proceeds along the arrow x1. The vertical axis represents the value of the induced voltage. The value of the vertical axis increases as it proceeds along the arrow y1.

  The undervoltage value calculation unit 93, the generator output value calculation unit 94, and the power generation control unit 95 will be described later. Note that the configuration of the main ECU 90 shown in FIG. 2 is a part of the configuration of the main ECU 90. The main ECU 90 has components other than the components shown in FIG. 2 and can perform various controls performed by the main ECU 90. As an example, as described above, the driving of the hybrid vehicle 10 is controlled.

  In the state where the shift position is the drive position P4, the main ECU 90 determines the induced voltage value calculated by the motor induced voltage value calculation unit 92 using the map M1 based on the detection result of the motor rotation speed detection sensor 22, and the battery voltage. The motor ECU 73 is controlled so that the value of the induced voltage generated by the electric motor 20 does not exceed the first predetermined voltage value V4 by comparing with the value. The motor ECU 73 operates based on the control of the main ECU 90 to control the operation of the motor conversion circuit 71. As a result, the value of the induced voltage generated by the electric motor 20 does not become larger than the voltage value of the battery 50. Thus, in this embodiment, motor ECU73 and main ECU90 comprise an example of the motor control means said by this invention.

  FIG. 4 is a graph showing the relationship between the voltage value of the battery 50 and the value of the induced voltage generated by the electric motor 20. The horizontal axis in FIG. 4 indicates the rotational speed of the output shaft 21 of the electric motor 20. The horizontal axis increases in value along the arrow x2. The vertical axis represents the voltage value. The value increases along the vertical axis as it proceeds along the arrow y2. In FIG. 4, the voltage value V2 of the battery 50 is indicated by a one-dot chain line, and the induced voltage value V3 generated by the electric motor 20 is indicated by a solid line. Note that the graph shown in FIG. 4 changes depending on the change in the voltage value of the battery 50.

  When there is no control by the motor ECU 73, that is, when the control by the motor ECU 73 is released, the value of the induced voltage generated by the electric motor 20 increases in direct proportion to the rotational speed of the output shaft 21 of the electric motor 20. For this reason, when the value of the induced voltage becomes equal to or higher than the first predetermined voltage value V4 of the battery 50, the motor conversion circuit 71 is controlled so that the value of the induced voltage becomes less than the first predetermined voltage value V4.

As described above, the value V3 of the induced voltage of the electric motor 20 is controlled to be less than the value obtained by subtracting the predetermined value ΔV1 from the voltage value V2 of the battery 50. The predetermined value ΔV1 is a predetermined value set in advance and is a constant value. The predetermined value ΔV1 can be arbitrarily set. In FIG. 4, the rotation of the output shaft 21 of the electric motor 20 when the main ECU 90 does not perform control to prevent the induced voltage value from exceeding the voltage value of the battery 50. The induced voltage value with respect to the number is indicated by a two-dot chain line. As indicated by a two-dot chain line, the value of the induced voltage generated by the electric motor 20 increases linearly in direct proportion to the rotational speed of the output shaft 21.

  Next, the operation of the main ECU 90 in the state where the shift position is in the neutral position is the main ECU 90 when the shift position is changed from the drive position P4 to the neutral position P3 during high speed travel when the time t1 after the start of operation elapses. The operation will be described as an example.

  FIG. 5 is a graph showing the value of the induced voltage generated by the electric motor 20 and the voltage value of the battery 50 according to the traveling example of the hybrid vehicle 10 described above. The horizontal axis in FIG. 5 indicates the travel time of the hybrid vehicle 10. The horizontal axis indicates that the traveling time increases as the vehicle travels along the arrow x3. One end of the horizontal axis opposite to the direction along the arrow x3 indicates when the hybrid vehicle 10 starts traveling. The vertical axis in FIG. 5 indicates the voltage value. The vertical axis indicates that the value increases as it proceeds along the arrow y3.

  First, the undervoltage value calculation unit 93, the generator output value calculation unit 94, and the power generation control unit 95 will be described. The insufficient voltage value calculation unit 93 calculates the insufficient value of the voltage value V2 of the battery 50 with respect to the second predetermined voltage value V5 that is a value obtained by adding the predetermined value ΔV1 to the induced voltage value V3 generated by the electric motor 20. Specifically, V5-V2 is calculated.

  The generator output value calculation unit 94 calculates an output value to be generated by the generator 65 corresponding to the calculation result of the undervoltage value calculation unit 93. Specifically, the generator output value calculation unit 94 includes a map M <b> 2 that indicates an output value corresponding to the calculation result of the undervoltage value calculation unit 93. FIG. 6 is a flowchart showing the operation of the generator output value calculation unit 94. A map M2 is shown in FIG. The horizontal axis of the map M2 indicates the insufficient value of the voltage value of the battery 50 relative to the value of the induced voltage generated by the electric motor 20. The horizontal axis indicates that the value increases as it proceeds along the arrow x4. The vertical axis represents the output. The unit is KW (kilowatt). The vertical axis indicates that the value increases as it proceeds along the arrow y4.

  Next, the operation will be described. FIG. 7 is a flowchart showing the operation of the main ECU 90. As shown in FIG. 7, in step ST1, the main ECU 90 determines whether or not the shift position is the neutral position P3. Specifically, shift position determination unit 91 determines a shift position based on information transmitted from shift position sensor 75, and determines whether or not the shift position is neutral position P3.

  In this description, the shift position is at the drive position P4 until the time t1 after the start of traveling elapses. For this reason, the operation of step ST1 is repeated until the time t1 elapses.

  When time t1 has elapsed after the start of traveling, the driver changes the shift lever 76 from the drive position P4 to the neutral position P3. Therefore, the shift position determination unit 91 determines that the shift position is the neutral position P3, and transmits information that the shift position is the neutral position P3 to the motor induced voltage value calculation unit 92. Then, the process proceeds to step ST2.

  Further, the main ECU 90 sets the neutral state when the shift position becomes the neutral position. The neutral state is a state where power supply from the inverter 70 to the electric motor 20 is interrupted, that is, a state where the electric motor 20 is opened to the inverter 70. In the neutral state, even if the driver depresses the accelerator pedal 15, the electric power is not supplied from the inverter 70 to the electric motor 20, so the electric motor 20 is not driven by receiving electric power.

  In step ST2, upon receiving information that the shift position is the neutral position P3, the motor induced voltage value calculation unit 92 receives the value of the induced voltage generated by the electric motor 20 based on the rotation speed of the output shaft 21 of the electric motor 20. Is calculated.

  Specifically, the motor induced voltage value calculation unit 92 performs the operation shown in FIG. When receiving information that the shift position is the neutral position P3, the motor-induced voltage value calculation unit 92 uses the map M1 based on the rotation speed information of the output shaft 21 of the electric motor 20 in step ST21. The value of the induced voltage generated by 20 is calculated. When the induced voltage value is calculated, the motor induced voltage value calculation unit 92 transmits the calculation result to the undervoltage value calculation unit 93. Then, the process proceeds to step ST3.

  In step ST3, the undervoltage value calculator 93 calculates the second predetermined voltage value V5 based on the value of the induced voltage calculated in step ST2, and the voltage value of the battery 50 with respect to the second predetermined voltage value V5. Calculate the missing value of. This insufficient voltage value may simply be the difference between the voltage value of the battery 50 and the induced voltage. The undervoltage value calculation unit 93 transmits the calculation result to the generator output value calculation unit 94. Then, the process proceeds to step ST4.

  In step ST4, the generator output value calculation unit 94 calculates an output value to be generated by the generator 65. Specifically, as illustrated in FIG. 6, the generator output value calculation unit 94 should generate power using the map M2 based on the calculation result of the undervoltage value calculation unit 93 in step ST31. Calculate the output value.

  The map M2 will be specifically described. As described above, in the map M2, the horizontal axis indicates the undervoltage value calculated in step ST3. A positive undervoltage value indicates that the second predetermined voltage value V5 is greater than the voltage value of the battery 50. That the undervoltage value is negative indicates that the voltage value of the battery 50 is larger than the second predetermined voltage value V5.

  When the generator output value calculation unit 94 calculates the output value to be generated by the generator 65, the calculation result is transmitted to the power generation control unit 95. Then, the process proceeds to step ST5.

  In step ST5, the power generation control unit 95 calculates the rotational speed and torque of the output shaft 26 of the engine 25 required for the engine 25 when generating the output value calculated in step ST4. As described above, the generator 65 is driven by the engine 25.

  For this reason, in order for the generator 65 to generate the output of the calculation result in step ST4, the engine 25 must generate the output value of the calculation result in step ST4. Note that the output generated by the engine 25 is set to a slightly large value in consideration of the loss at the time of transmission to the generator 65. Further, the power generation control unit 95 controls the generator ECU 74 so as to output the torque of the engine 25 when the transmission loss to the generator 65 is not considered. As a result, the torque transmitted from the engine 25 to the generator 65 and the torque supported by the generator 65 are the same.

  The output generated by the generator 65 by the above control is the same as the output calculated in step ST4. The electric power generated by the generator 65 is converted into DC power via the generator conversion circuit 72 and then charged to the battery 50. Due to the power generation by the generator, the voltage value of the battery 50 increases. Moreover, you may raise the voltage value of the battery 50 by repeating operation | movement of step ST1-ST5.

  The map M2 indicates that the output to be generated by the generator 65 is greater than zero when the undervoltage value is −ΔV1 or more. In other words, even when the shift position is at the neutral position P3, if the second predetermined voltage value V5- (voltage value V2 of the battery 50) is less than ΔV1, the power generation control unit 95 causes the battery 50 to be Charged (battery voltage rise). As a result, even when the shift position is in the neutral position P3, the voltage value of the battery 50 is maintained to be larger by ΔV1 than the value of the induced voltage generated by the electric motor 20. In other words, a value larger than the second predetermined voltage value V5 is maintained.

  In the present embodiment, the map M2 sets the output to be generated by the generator 65 to zero when the undervoltage value is less than −ΔV1. The power generation control unit 95 does not control the engine ECU 30 and the generator ECU 74 when the output value calculated in step ST4 is zero. In other words, when the battery 50 is charged (battery voltage rise) and the voltage value of the battery 50 becomes larger than the second predetermined voltage value V5, the charging operation of the battery 50 is stopped.

  As a result, as shown in FIG. 5, in the hybrid vehicle 10, the voltage value of the battery 50 is maintained larger than the second predetermined voltage value V5 even when the shift position is at the neutral position P3.

  For this reason, even if the shift position is changed from the neutral position P3 to the drive position P4 when the time t2 has elapsed after the start of operation, no malfunction occurs in the operation of the electric motor 20.

  In the hybrid vehicle 10 of the present embodiment, when the shift position is in the neutral position P3, when the voltage value of the battery 50 becomes equal to or lower than the second predetermined voltage value V5, the generator 65 is driven and the battery 50 is charged. Is done. As a result, the voltage value of the battery 50 increases.

  In this way, in the state where the shift position is at the neutral position P3, the voltage value of the battery 50 is changed by charging the battery 50, instead of changing the value of the induced voltage generated by the electric motor 20. As a result, a malfunction occurs in the operation of the electric motor 20 when the shift position is changed from the neutral position P3 to the drive position P4 while keeping the power supply from the inverter 70 to the electric motor 20 cut off. Can be suppressed.

  Further, since the occurrence of a malfunction in the operation of the electric motor 20 is suppressed by increasing the voltage value of the battery 50, the second voltage even if the voltage value of the induced voltage generated by the electric motor 20 is not controlled by the inverter 70. Since it is not necessary to design the electric motor 20 so as not to exceed the predetermined voltage value V5, it is not necessary to reduce the torque of the electric motor 20. For this reason, the electric motor 20 can be designed so as to obtain a sufficient torque for the traveling of the hybrid vehicle 10.

  Further, the charging of the battery 50 is continued until the voltage value of the battery 50 exceeds the second predetermined voltage value V5 in a state where the shift position is at the neutral position P3. For this reason, when the shift position is changed from the neutral position P3 to the drive position P4, the occurrence of problems in the operation of the electric motor 20 is further suppressed.

  In the present embodiment, charging of the battery 50 is started when the voltage value of the battery 50 is equal to or lower than the second predetermined voltage value V5 in a state where the shift position is at the neutral position P3.

  However, when the shift position is in the neutral position, the voltage value of the battery 50 only needs to be higher than the induced voltage value of the electric motor 20. Therefore, in the state where the shift position is at the neutral position P3, when the value of the induced voltage generated by the electric motor 20 becomes equal to or higher than the voltage value of the battery 50, the generator 65 is driven to charge the battery 50 (the battery voltage rises). ).

  This charging is continued so that the voltage value of the battery 50 becomes larger than the value of the induced voltage generated by the electric motor 20. As a result, in a state where the shift position is at the neutral position P3, the state where the voltage value of the battery 50 is larger than the value of the induced voltage generated by the electric motor 20 is maintained, so that the shift position is driven from the neutral position P3. Even if the position P4 is changed, there is no problem in the operation of the electric motor 20.

  In the present embodiment, when the shift position is at the drive position, as an example, the induced voltage value of the electric motor 20 is controlled to be less than the first predetermined voltage value V4. For this reason, the induced voltage value of the electric motor 20 is less than the voltage value of the battery 50. However, when the shift position is at the drive position, the induced voltage value of the electric motor 20 may be equal to or less than the voltage value of the battery 50. For this reason, when the shift position is at the drive position, the voltage value of the battery 50 is used instead of the first predetermined voltage value V4 as a comparison target of the induced voltage value of the electric motor 20, and the induced voltage value of the electric motor 20 is The electric motor 20 may be controlled so as to be equal to or lower than the voltage value of the battery 50.

  In the present embodiment, the traveling mode of the hybrid electric vehicle 10 may include a traveling mode in which the electric motor 20 and the engine 25 are traveled together.

  The induced voltage value generated by the electric motor 20 used in the present embodiment is a value obtained by the motor rotation speed detection sensor 22 and the main ECU 90. The motor rotation speed detection sensor 22 and the main ECU 90 constitute an example of an induced voltage value detection unit that detects an induced voltage of the electric motor 20. The induced voltage value detecting means may be other than the above. Like this embodiment, it may be comprised by the combination of a some component, and may be comprised only by one component. In short, the induced voltage value detecting means only needs to have a function of obtaining an induced voltage value generated by the electric motor.

  The shift position sensor 75 is an example of the shift position detecting means referred to in the present invention. The shift position detecting means may be other than the above. Like this embodiment, it may be comprised only by one component, and may be comprised combining a some component. In short, it is only necessary to have a function of detecting the shift position.

  The motor rotation speed detection sensor 22 is an example of the rotation speed detection means referred to in the present invention. The rotational speed detection means may be other than the above. Like this embodiment, it may be comprised only by one component, and may be comprised combining a some component. In short, what is necessary is just to have the function to detect the rotation speed of an electric motor.

  The motor ECU 73 and the main ECU 90 constitute an example of the motor control means referred to in the present invention. The motor control means may be other than the above. As in the present embodiment, a plurality of components may be combined and configured with only one component. In short, what is necessary is just to have a function which controls an electric motor so that the induced voltage value of an electric motor may become below the voltage value of a battery.

  The undervoltage value calculation unit 93 is an example of a voltage difference calculation unit referred to in the present invention. The voltage difference calculation means may be other than the above. Like this embodiment, it may be comprised only by one component, and may be comprised combining a some component. In short, it is only necessary to have a function of calculating the difference between the voltage value of the battery and the induced voltage value of the electric motor.

  When the control of the electric motor 20 by the motor ECU 73 is released, the main ECU 90 controls the generator 65 to make the voltage value of the battery 50 higher than the induced voltage value of the electric motor 20. Thus, the hybrid vehicle 10 includes control means for controlling the generator when control of the electric motor by the electric motor control means is released. This control means may be other than the main ECU 90. Like this embodiment, it may be comprised only by one component, and may be comprised combining a some component. In short, when the control of the electric motor by the electric motor control means is released, the battery may be charged by the generator so that the voltage value of the battery becomes higher than the induced voltage value of the electric motor.

  The main ECU 90 controls the generator 65 so that the generator 65 charges a voltage shortage that is the difference between the induced voltage value of the electric motor 20 and the voltage value of the battery 50. Thus, the hybrid vehicle 10 includes control means for controlling the generator so that the generator is charged with a voltage shortage that is the difference between the induced voltage value and the voltage value of the battery. This control means may be other than the main ECU 90. Like this embodiment, it may be comprised only by one component, and may be comprised combining a some component. The control means may be the same as the control means for controlling the generator when the motor control by the motor control means is released. In short, what is necessary is just to have a function which controls a generator so that the voltage shortage which is the difference of the induced voltage value of an electric motor and the voltage value of a battery may be charged with a generator.

  In the present embodiment, the voltage value of the battery 50 is a value obtained by each CMU 52 and the battery ECU 60. Each CMU 52 and the battery ECU 60 constitute an example of the battery voltage value detection means referred to in the present invention. The battery voltage value detection means may be other than the above. It may be configured by combining a plurality of components as in this embodiment, or may be configured by only one component. In short, what is necessary is just to have the function to detect the voltage value of a battery.

  In the present embodiment, the hybrid vehicle 10 is used as an example of a hybrid vehicle. As the hybrid vehicle, the present invention may be used for vehicles other than the hybrid vehicle 10. For example, the present invention may be used for a train traveling on a track.

  In the present embodiment, the hybrid vehicle 10 does not include a transmission that changes the rotational speeds of the output shaft 21 of the electric motor 20 and the output shaft 26 of the engine 25 and transmits it to the front wheels 11. The neutral position P3 of the shift position used in the present embodiment does not indicate that the transmission is in the neutral state, but is a state where the supply of electric power from the inverter 70 to the electric motor 20 is interrupted. In other words, the neutral state is a state where the electric motor 20 does not operate due to depression of the accelerator pedal 15.

  The state in which the shift position is at the drive position P4 is a state in which power supply from the inverter 70 to the electric motor 20 is not interrupted. In other words, when the accelerator pedal 15 is depressed, the electric motor 20 is driven.

  In the present embodiment, the hybrid vehicle 10 has a parallel travel mode in which the vehicle travels using only the engine 25. Thus, in the case of having a travel mode in which the engine is driven in the configuration including the engine, the state where the shift position is in the drive position includes a state where the engine 25 is driven when the accelerator pedal 15 is depressed.

  The present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above-described embodiments. For example, you may delete some components from all the components shown by embodiment mentioned above.

  DESCRIPTION OF SYMBOLS 10 ... Hybrid vehicle (hybrid vehicle), 20 ... Electric motor (electric motor), 22 ... Motor rotation speed detection sensor (rotation speed detection means), 25 ... Engine, 50 ... Battery, 65 ... Generator, 73 ... Motor ECU (electric motor) Control means), 75... Shift position sensor (shift position detection means), 93... Undervoltage value calculation section (voltage difference calculation means).

Claims (4)

An electric motor for driving the vehicle;
A battery for supplying power to the motor;
A generator driven by an engine mounted on the vehicle to charge the battery;
Battery voltage value detecting means for detecting the voltage value of the battery;
In a hybrid vehicle comprising: motor control means for controlling the electric motor so that an induced voltage value of the electric motor is equal to or lower than a voltage value of the battery;
When the control of the electric motor by the electric motor control means is released, the battery is charged by the generator to make the voltage value of the battery higher than the induced voltage value. Further comprising shift position detecting means for detecting the position of the shift position of the vehicle;
The hybrid vehicle according to claim 1, wherein the control by the electric motor control means is released when the shift position detection means detects the neutral position. Voltage difference calculating means for calculating a difference between the voltage value and the induced voltage value;
The hybrid vehicle according to claim 1, wherein a voltage deficiency that is a difference between the induced voltage value and the voltage value is charged by the generator. A rotation number detecting means for detecting the rotation number of the electric motor;
The hybrid vehicle according to any one of claims 1 to 3, wherein the induced voltage value is calculated based on a rotational speed of the electric motor.

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