JP2010012827A - Vehicle and control method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable the much longer continuation of traveling of a vehicle only with the power of a motor in an abnormal time when a power generator can not be normally driven. <P>SOLUTION: When prescribed abnormality causing impossibility of the normal driving of a first motor (MG1) occurs within a range where the gate shielding of an invertor for driving the first motor is possible, the island operation of an engine is performed with the highest engine speed Nemax in such a state that an invertor for the first motor is gate-shifted (S150, S160), and a target voltage VH* of a high voltage system is set so that the maximum generated power which can be generated by the first motor which revolves with the number of revolutions Nm1, and generates a counter-electromotive power can be generated, and the driving of a booster circuit is controlled so that the voltage VH of the high voltage system becomes the set target voltage VH* (S180, S190), and a second motor (MG) is controlled so that a vehicle can travel with request torque Tr* within the range of the input/output restriction Win and Wout of a battery (S110 to S150). Thus, it is possible to continue the traveling of the vehicle longer only with power from the second motor. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicle and a control method thereof.

Conventionally, as this type of vehicle, an engine, a generator that rotates by the power of the engine to generate electric power, an electric motor connected to a drive shaft connected to an axle, a chargeable / dischargeable battery, an electric generator and an electric motor Has been proposed that includes a booster circuit that is disposed between each drive circuit that drives the battery and a battery (see, for example, Patent Document 1). In this vehicle, when abnormality occurs in the battery, the generator after the battery is shut off by controlling the booster circuit in advance so that the system voltage on the side of each drive circuit is higher than the counter electromotive voltage generated by the generator from the booster circuit. A battery that travels by outputting power from the electric motor using electric power generated by the generator by using the power of the engine, cutting off the connection between the battery and each drive circuit after that, It is supposed to be running less.
JP 2007-210413 A

  In the above-described vehicle, when an abnormality that prevents the generator from being normally driven occurs, it is desirable that the retreat travel using only the electric power of the electric motor using the electric power of the battery can be continued for as long as possible. It is. For this reason, even when the generator cannot be driven normally, for example, when the sensor that detects the rotational position of the rotor of the generator fails or when some of the switching elements of the generator drive circuit are not turned on When it is possible to stop the driving of the generator drive circuit and the generated power by the back electromotive force generated by the generator can be used for driving the motor, it is desirable to increase this generated power as much as possible. .

  A vehicle and a control method thereof according to the present invention have a main object of enabling traveling using only the power of an electric motor to be continued for a longer time when there is an abnormality in which a generator cannot be driven normally.

  The vehicle and the control method thereof according to the present invention employ the following means in order to achieve at least the above-described main object.

The vehicle of the present invention
An internal combustion engine;
A generator that rotates at a rotational speed corresponding to the rotational speed of the internal combustion engine and generates a back electromotive force along with the rotational speed;
An inverter circuit for a generator that drives the generator;
An electric motor that can input and output power to the axle;
An inverter circuit for an electric motor that drives the electric motor;
Charge / discharge power storage means;
It is interposed between the low voltage system to which the power storage means is connected and the high voltage system to which the inverter circuit for the generator and the inverter circuit for the motor are connected, and adjusts the voltage of the high voltage system and the low voltage system. Voltage adjusting means for exchanging power between the system and the high voltage system;
A rotational speed acquisition means for acquiring the rotational speed of the generator;
There is a predetermined abnormality in which the generator cannot be normally driven within a range in which the gate of the inverter circuit for the generator can be shut off due to an abnormality in equipment or parts necessary for driving the generator including the inverter circuit for the generator. When it occurs, the internal combustion engine and the generator inverter circuit are controlled such that the internal combustion engine is operated independently at a predetermined rotational speed with the generator inverter circuit being gate-cut, and the acquired rotation is controlled. The obtained power is generated in the generator within a predetermined power range near the upper limit, with the maximum generated power that can be generated by the generator rotating by a number and generating counter electromotive force as an upper limit. A target voltage for the high voltage system is set based on the number of revolutions, and the voltage adjusting means is controlled so that the voltage of the high voltage system is adjusted to the set target voltage. And abnormality control means for controlling the inverter circuit for the motor so that the driving force based on the required driving force travels is outputted from the electric motor to be,
It is a summary to provide.

  In the vehicle according to the present invention, the number of revolutions of the generator is acquired, and the gate of the inverter circuit for the generator can be shut off due to an abnormality in equipment or parts necessary for driving the generator including the inverter circuit for the generator. An internal combustion engine and an inverter circuit for a generator so that the internal combustion engine can be operated independently at a predetermined rotational speed in a state where a gate of the inverter circuit for the generator is shut off when a predetermined abnormality that prevents the generator from being driven normally occurs. The generator generates the generated power in the predetermined power range near the upper limit, with the maximum generated power that can be generated by the generator rotating at the acquired rotational speed and generating counter electromotive force as the upper limit. The required driving force required for driving is set by setting the target voltage of the high voltage system based on the obtained rotation speed and controlling the voltage adjusting means so that the voltage of the high voltage system is adjusted to the set target voltage. Driving force based controls motor inverter circuit so as to travel is output from the motor. Thereby, since the electric power in the vicinity of the upper limit of the generated electric power that can be generated by the generator that generates the counter electromotive force can be used for driving the electric motor, it is possible to continue traveling with only the electric power of the electric motor for a longer time. Here, the “predetermined abnormality” includes an abnormality of a sensor that detects the rotational position of the rotor of the generator, an abnormality of a sensor that detects a phase current flowing through the stator of the generator, and an inverter circuit for the generator. An abnormality that prevents the switching element of the part from being turned on is included. Further, the “predetermined rotational speed” includes the maximum rotational speed as a rated value of the internal combustion engine.

  In such a vehicle of the present invention, the abnormal time control means predetermines and stores a rotational speed target voltage relationship, which is a relationship between the rotational speed of the generator and the target voltage of the high voltage system, by experiment or analysis and The high-voltage system target voltage may be set based on the acquired rotational speed and the stored rotational speed target voltage relationship, and the abnormality control means may be the generator. When the generated counter electromotive force is expressed as a product of the rotational speed of the generator and a predetermined coefficient, the product of the acquired rotational speed, the predetermined coefficient, and a value ½ is the target of the high voltage system. It may be a means for setting as a voltage. In this way, the target voltage of the high voltage system can be set more reliably.

  In the vehicle according to the present invention, the abnormality control means may include the internal combustion engine, the generator inverter circuit, and the motor inverter when the predetermined abnormality occurs while the internal combustion engine is being operated. It may be a means for controlling the circuit and the voltage adjusting means.

  Further, in the vehicle according to the present invention, the drive shaft connected to the axle, the output shaft of the internal combustion engine, and the rotation shaft of the generator are connected to three shafts, and any two of the three shafts are inserted. A three-axis power input / output means for inputting / outputting power to / from the remaining shafts based on the output power may be provided. Here, the “three-axis power input / output means” may be a single pinion type or double pinion type planetary gear mechanism, or may be a differential gear.

The vehicle control method of the present invention includes:
An internal combustion engine, a generator that rotates at a rotational speed corresponding to the rotational speed of the internal combustion engine and generates a back electromotive force with the rotation, an inverter circuit for a generator that drives the generator, and power to the axle An electric motor capable of inputting / outputting, an inverter circuit for an electric motor that drives the electric motor, an electric storage means that can be charged / discharged, a low voltage system connected to the electric storage means, the inverter circuit for the generator, and the inverter circuit for the electric motor A vehicle control method comprising: a voltage adjusting unit that is interposed between a connected high voltage system and adjusts a voltage of the high voltage system, and exchanges power between the low voltage system and the high voltage system. Because
Obtaining the rotational speed of the generator,
There is a predetermined abnormality in which the generator cannot be normally driven within a range in which the gate of the inverter circuit for the generator can be shut off due to an abnormality in equipment or parts necessary for driving the generator including the inverter circuit for the generator. When it occurs, the internal combustion engine and the generator inverter circuit are controlled such that the internal combustion engine is operated independently at a predetermined rotational speed with the generator inverter circuit being gate-cut, and the acquired rotation is controlled. The obtained power is generated in the generator within a predetermined power range near the upper limit, with the maximum generated power that can be generated by the generator rotating by a number and generating counter electromotive force as an upper limit. A target voltage for the high voltage system is set based on the number of revolutions, and the voltage adjusting means is controlled so that the voltage of the high voltage system is adjusted to the set target voltage. Driving force based on the required driving force controls the inverter circuit for the motor to run is output from the electric motor to be,
It is characterized by that.

  In this vehicle control method of the present invention, the number of revolutions of the generator is acquired, and the gate of the inverter circuit for the generator can be shut off due to an abnormality in equipment or parts necessary for driving the generator including the inverter circuit for the generator. For internal combustion engines and generators so that the internal combustion engine can be operated independently at a predetermined speed with the inverter circuit for the generator shut off when a predetermined abnormality occurs that prevents the generator from being driven normally within the range. The generator power that is in the predetermined power range near the upper limit is defined as the upper limit of the maximum generated power that can be generated by the generator that controls the inverter circuit and rotates at the acquired number of revolutions to generate counter electromotive force. The target voltage of the high voltage system is set based on the rotation speed acquired so as to be generated at the same time, and the voltage adjusting means is controlled so that the voltage of the high voltage system is adjusted to the set target voltage. Calculated driving force based on the driving force controls the electric motor inverter circuit so as to travel is output from the motor. Thereby, since the electric power in the vicinity of the upper limit of the generated electric power that can be generated by the generator that generates the counter electromotive force can be used for driving the electric motor, it is possible to continue traveling with only the electric power of the electric motor for a longer time. Here, the “predetermined abnormality” includes an abnormality of a sensor that detects the rotational position of the rotor of the generator, an abnormality of a sensor that detects a phase current of the inverter circuit for the generator, and a part of the inverter circuit for the generator. An abnormality that prevents the switching element from being turned on is included. Further, the “predetermined rotational speed” includes the maximum rotational speed as a rated value of the internal combustion engine.

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

  FIG. 1 is a configuration diagram showing an outline of the configuration of a hybrid vehicle 20 according to an embodiment of the present invention. As shown in the figure, the hybrid vehicle 20 of the embodiment includes an engine 22, a three-shaft power distribution / integration mechanism 30 connected to a crankshaft 26 as an output shaft of the engine 22 via a damper 28, and power distribution / integration. A motor MG1 capable of generating electricity connected to the mechanism 30, a motor MG2 connected to a ring gear shaft 32a as a drive shaft connected to the power distribution and integration mechanism 30 via a reduction gear 35, and a direct current converted into an alternating current Inverters 41 and 42 that can be supplied to the motors MG1 and MG2, a booster circuit 55 that converts the voltage of the electric power from the battery 50 and can be supplied to the inverters 41 and 42, and an electronic control for hybrid that controls the entire vehicle A unit 70.

  The engine 22 is an internal combustion engine that outputs power using a hydrocarbon-based fuel such as gasoline or light oil. The engine electronic control unit (hereinafter referred to as engine ECU) 24 performs fuel injection control, ignition control, and intake air amount adjustment. Under control of operation such as control. The engine ECU 24 receives signals from various sensors that detect the operating state of the engine 22, for example, a crank position from a crank position sensor (not shown) that detects the crank angle of the crankshaft 26 of the engine 22. The engine ECU 24 is in communication with the hybrid electronic control unit 70, controls the operation of the engine 22 by a control signal from the hybrid electronic control unit 70, and, if necessary, transmits data related to the operating state of the engine 22 to the hybrid electronic control. Output to unit 70. The engine ECU 24 also calculates the rotational speed of the crankshaft 26, that is, the rotational speed Ne of the engine 22, based on a crank position from a crank position sensor (not shown).

  The power distribution and integration mechanism 30 includes an external gear sun gear 31, an internal gear ring gear 32 arranged concentrically with the sun gear 31, a plurality of pinion gears 33 that mesh with the sun gear 31 and mesh with the ring gear 32, A planetary gear mechanism is provided that includes a carrier 34 that holds a plurality of pinion gears 33 so as to rotate and revolve, and that performs differential action using the sun gear 31, the ring gear 32, and the carrier 34 as rotational elements. In the power distribution and integration mechanism 30, the crankshaft 26 of the engine 22 is connected to the carrier 34, the motor MG1 is connected to the sun gear 31, and the reduction gear 35 is connected to the ring gear 32 via the ring gear shaft 32a. When functioning as a generator, power from the engine 22 input from the carrier 34 is distributed according to the gear ratio between the sun gear 31 side and the ring gear 32 side, and when the motor MG1 functions as an electric motor, the engine input from the carrier 34 The power from 22 and the power from the motor MG1 input from the sun gear 31 are integrated and output to the ring gear 32 side. The power output to the ring gear 32 is finally output from the ring gear shaft 32a to the drive wheels 63a and 63b of the vehicle via the gear mechanism 60 and the differential gear 62.

  Each of the motor MG1 and the motor MG2 is configured as a well-known synchronous generator motor including a rotor on which a permanent magnet is attached and a stator on which a three-phase coil is wound. As shown in the block diagram of the electric drive system including the motors MG1 and MG2 in FIG. 2, the inverters 41 and 42 are in reverse directions to the six transistors T11 to T16 and T21 to 26 and the transistors T11 to T16 and T21 to T26. 6 diodes D11 to D16, D21 to D26 connected in parallel. Two transistors T11 to T16 and T21 to T26 are arranged in pairs so that each of the inverters 41 and 42 becomes a source side and a sink side with respect to the positive electrode bus 54a and the negative electrode bus 54b shared by the power line 54. Each of the three-phase coils (U-phase, V-phase, W-phase) of the motors MG1, MG2 is connected to each connection point between the paired transistors. Therefore, a rotating magnetic field is formed in the three-phase coil by controlling the ratio of the on-time of the transistors T11 to T16 and T21 to T26 that make a pair while a voltage is acting between the positive electrode bus 54a and the negative electrode bus 54b. The motors MG1, MG2 can be driven to rotate. Since the inverters 41 and 42 share the positive bus 54a and the negative bus 54b, the electric power generated by either the motor MG1 or MG2 can be supplied to another motor. A smoothing capacitor 57 is connected to the positive bus 54a and the negative bus 54b. The motors MG1 and MG2 are both driven and controlled by a motor electronic control unit (hereinafter referred to as a motor ECU) 40. The motor ECU 40 receives signals necessary for driving and controlling the motors MG1 and MG2, such as signals from rotational position detection sensors 43 and 44 for detecting the rotational position of the rotors of the motors MG1 and MG2, and three signals of the motors MG1 and MG2. Each phase current from the current sensors 45U, 45V, 46U, 46V for detecting the phase current flowing in the U phase and V phase of the phase coil, each inverter temperature from a temperature sensor (not shown) attached to the inverters 41, 42, etc. are input. The motor ECU 40 outputs a switching control signal to the inverters 41 and 42. The motor ECU 40 is in communication with the hybrid electronic control unit 70, controls the driving of the motors MG1 and MG2 by a control signal from the hybrid electronic control unit 70, and, if necessary, data on the operating state of the motors MG1 and MG2. Output to the hybrid electronic control unit 70. The motor ECU 40 also calculates the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 based on signals from the rotational position detection sensors 43 and 44.

  As shown in FIG. 2, the booster circuit 55 is configured as a boost converter including two transistors T31 and T32, two diodes D31 and D32 connected in parallel to the transistors T31 and T32 in the reverse direction, and a reactor L. . The two transistors T31 and T32 are connected to the positive bus 54a and the negative bus 54b of the inverters 41 and 42, respectively, and the reactor L is connected to the connection point. Further, a positive terminal and a negative terminal of battery 50 are connected to reactor L and negative bus 54b, respectively. Therefore, by turning on / off the transistors T31 and T32, the voltage of the DC power of the battery 50 is boosted and supplied to the inverters 41 and 42, or the DC voltage acting on the positive bus 54a and the negative bus 54b is lowered. The battery 50 can be charged. A smoothing capacitor 58 is connected to the reactor L and the negative electrode bus 54b. Hereinafter, the power line 54 side of the booster circuit 55 is referred to as a high voltage system, and the battery 50 side of the booster circuit 55 is referred to as a low voltage system.

  The battery 50 is configured as a secondary battery such as a nickel hydride secondary battery or a lithium ion secondary battery, and is managed by a battery electronic control unit (hereinafter referred to as a battery ECU) 52. The battery ECU 52 receives signals necessary for managing the battery 50, for example, a voltage between terminals from a voltage sensor (not shown) installed between terminals of the battery 50, and a power line 54 connected to the output terminal of the battery 50. The charging / discharging current from the attached current sensor (not shown), the battery temperature Tb from the temperature sensor 51 attached to the battery 50, and the like are input. Output to the control unit 70. Further, the battery ECU 52 calculates the remaining capacity SOC based on the integrated value of the charge / discharge current detected by the current sensor in order to manage the battery 50, or the battery ECU 52 based on the calculated remaining capacity SOC and the battery temperature Tb. The input / output limits Win and Wout, which are the maximum allowable power that may charge / discharge 50, are calculated. The input / output limits Win and Wout of the battery 50 are set to basic values of the input / output limits Win and Wout based on the battery temperature Tb, and the output limit correction coefficient and the input limit are set based on the remaining capacity SOC of the battery 50. It can be set by setting a correction coefficient and multiplying the basic value of the set input / output limits Win and Wout by the correction coefficient.

  The hybrid electronic control unit 70 is configured as a microprocessor centered on the CPU 72, and in addition to the CPU 72, a ROM 74 for storing processing programs, a RAM 76 for temporarily storing data, an input / output port and communication not shown. And a port. In the hybrid electronic control unit 70, the voltage of the capacitor 57 (hereinafter referred to as a high voltage system voltage) VH from the voltage sensor 57 a attached between the terminals of the capacitor 57 and the voltage sensor attached between the terminals of the capacitor 58. The voltage VL of the capacitor 58 from 58a, the ignition signal from the ignition switch 80, the shift position SP from the shift position sensor 82 that detects the operation position of the shift lever 81, and the accelerator pedal position sensor 84 that detects the depression amount of the accelerator pedal 83 The accelerator pedal opening Acc from the vehicle, the brake pedal position BP from the brake pedal position sensor 86 for detecting the depression amount of the brake pedal 85, the vehicle speed V from the vehicle speed sensor 88, and the like are input via the input port. The hybrid electronic control unit 70 outputs a switching control signal to the switching element of the booster circuit 55 through the output port. As described above, the hybrid electronic control unit 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via the communication port, and exchanges various control signals and data with the engine ECU 24, the motor ECU 40, and the battery ECU 52. ing.

  The hybrid vehicle 20 of the embodiment thus configured calculates the required torque to be output to the ring gear shaft 32a as the drive shaft based on the accelerator opening Acc and the vehicle speed V corresponding to the depression amount of the accelerator pedal 83 by the driver. Then, the operation of the engine 22, the motor MG1, and the motor MG2 is controlled so that the required power corresponding to the required torque is output to the ring gear shaft 32a. As operation control of the engine 22, the motor MG1, and the motor MG2, the operation of the engine 22 is controlled so that power corresponding to the required power is output from the engine 22, and all of the power output from the engine 22 is the power distribution and integration mechanism 30. Torque conversion operation mode for driving and controlling the motor MG1 and the motor MG2 so that the torque is converted by the motor MG1 and the motor MG2 and output to the ring gear shaft 32a, and the required power and the power required for charging and discharging the battery 50. The engine 22 is operated and controlled so that suitable power is output from the engine 22, and all or part of the power output from the engine 22 with charging / discharging of the battery 50 is the power distribution and integration mechanism 30, the motor MG1, and the motor. The required power is converted to the ring gear shaft 32 with torque conversion by MG2. Charge / discharge operation mode in which the motor MG1 and the motor MG2 are driven and controlled so as to be output to each other, and a motor operation mode in which the operation of the engine 22 is stopped and the power corresponding to the required power from the motor MG2 is output to the ring gear shaft 32a. and so on.

  Next, the operation of the thus configured hybrid vehicle 20 of the embodiment will be described. FIG. 3 is a flowchart showing an example of an abnormal time drive control routine executed by the hybrid electronic control unit 70. This routine is performed every predetermined time (for example, every several msec) when a predetermined abnormality occurs in which the motor MG1 cannot be normally driven within a range in which the gate of the inverter 41 can be cut off while the engine 22 is operating. Repeatedly. Here, the predetermined abnormality includes failure of the rotation position detection sensor 43 that detects the rotation position of the rotor of the motor MG1, failure of the current sensors 45U and 45V that detect the phase current of the motor MG1, and transistors T11 to T11 of the inverter 41. There is a failure in which a part of T16 is not turned on (a failure fixed in an off state). In the embodiment, when a predetermined abnormality occurs while the operation of the engine 22 is stopped, the drive control for the motor operation mode is continued.

  When the abnormal time drive control routine is executed, the CPU 72 of the hybrid electronic control unit 70 firstly, the accelerator opening degree Acc from the accelerator pedal position sensor 84, the vehicle speed V from the vehicle speed sensor 88, the rotational speed Nm2, of the motor MG2, and so on. A process of inputting data necessary for control, such as input / output limits Win and Wout of the battery 50 and the high-voltage voltage VH from the voltage sensor 57a, is executed (step S100). Here, the rotational speed Nm2 of the motor MG2 is calculated from the rotational position of the rotor of the motor MG2 detected by the rotational position detection sensor 44 and is input from the motor ECU 40 by communication. Further, the input / output limits Win and Wout of the battery 50 are set based on the battery temperature Tb of the battery 50 and the remaining capacity SOC of the battery 50 and are input from the battery ECU 52 by communication.

  When the data is thus input, the required torque Tr * to be output to the ring gear shaft 32a as the drive shaft connected to the drive wheels 63a and 63b as the torque required for the vehicle based on the input accelerator opening Acc and the vehicle speed V. Is set (step S110). In the embodiment, the required torque Tr * is determined in advance by storing the relationship between the accelerator opening Acc, the vehicle speed V, and the required torque Tr * in the ROM 74 as a required torque setting map, and the accelerator opening Acc, the vehicle speed V, , The corresponding required torque Tr * is derived and set from the stored map. FIG. 4 shows an example of the required torque setting map.

  Subsequently, the set required torque Tr * is divided by the gear ratio Gr of the reduction gear 35 to calculate a temporary torque Tm2tmp which is a temporary value of torque to be output from the motor MG2 (step S120), and the input battery 50 Are divided by the rotational speed Nm2 of the motor MG2 to calculate torque limits Tmin and Tmax as upper and lower limits of torque that may be output from the motor MG2 (step S130), and set temporary torque The torque command Tm2 * of the motor MG2 is set by limiting Tm2tmp with the torque limits Tmin and Tmax according to the following equation (1) (step S140).

  Tm2 * = max (min (Tm2tmp, Tmax), Tmin) (1)

  Next, the gate cutoff command of inverter 41 that drives motor MG1 and the set torque command Tm2 * of motor MG2 are transmitted to motor ECU 40 (step S150). The motor ECU 40 that has received the gate cutoff command and the torque command Tm2 * shuts off the inverter 41 (turns off the transistors T11 to T16) and drives the motor MG2 with the torque command Tm2 * when the inverter 41 is not gate cut off. Thus, switching control of the transistors T21 to T26 of the inverter 42 is performed.

  When the inverters 41 and 42 are controlled in this way, the maximum rotational speed Nemax (for example, 5000 rpm or 6000 rpm) as a rated value is set as the target rotational speed Ne * for the independent operation of the engine 22 and transmitted to the engine ECU 24 (step S160). ). The engine ECU 24 that has received the target rotational speed Ne * performs control such as fuel injection control and ignition control in the engine 22 so that the engine ECU 24 is independently operated at the target rotational speed Ne *. Here, FIG. 5 shows an example of a collinear chart showing the relationship between the rotational speeds of the rotating elements of the power distribution and integration mechanism 30 when the inverter 41 is traveling with the autonomous operation of the engine 22 with the gate shut off. . In the figure, the left S-axis indicates the rotation speed of the sun gear 31 that is the rotation speed Nm1 of the motor MG1, the C-axis indicates the rotation speed of the carrier 34 that is the rotation speed Ne of the engine 22, and the R-axis indicates the rotation speed of the motor MG2. The rotational speed Nr of the ring gear 32 obtained by dividing the number Nm2 by the gear ratio Gr of the reduction gear 35 is shown. A thick arrow on the R axis indicates a torque that the torque Tm2 output from the motor MG2 acts on the ring gear shaft 32a through the reduction gear 35. As can be seen from FIG. 5, when the engine 22 is rotating, the motor MG1 rotates according to the rotational speed relationship of the rotating elements of the power distribution and integration mechanism 30. Electromotive voltage) is generated. The maximum rotation speed Nemax is set as the target rotation speed Ne * for the autonomous operation of the engine 22 because the rotation speed Nm1 of the motor MG1 changes according to the vehicle speed V, but the rotation speed Nm1 of the motor MG1 increases. This is because the generated counter electromotive force is increased, and thus the counter electromotive force is increased by rotating the motor MG1 in the range of the normal rotational speed as high as possible during traveling.

  Subsequently, the rotational speed Nm1 of the motor MG1 is input (step S170). The rotational speed Nm1 of the motor MG1 is calculated based on the rotational position of the rotor of the motor MG1 detected by the rotational position detection sensor 43 when the rotational position detection sensor 43 has not failed. Input via communication. When the rotational speed Nm1 of the motor MG1 cannot be calculated by the motor ECU 40 due to a failure of the rotational position detection sensor 43, the rotational speed Nm1 is calculated based on a crank position from a crank position sensor (not shown) and is calculated from the engine ECU 24. It is possible to input a value calculated by the following equation (2) using the rotation speed Ne of the engine 22, the rotation speed Nr of the ring gear 32, and the gear ratio ρ of the power distribution and integration mechanism 30 input by communication. Equation (2) can be easily derived by using the alignment chart of FIG. The rotational speed Nr of the ring gear shaft 32a is obtained by multiplying the vehicle speed V by a conversion factor k (Nr = k · V), or the rotational speed Nm2 of the motor MG2 is divided by the gear ratio Gr of the reduction gear 35 (Nr = Nm2). / Gr).

  Nm1 = Ne ・ (1 + ρ) / ρ-Nr / ρ (2)

  Then, the high voltage system target voltage VH * is set so as to generate as much generated power as possible in the motor MG1 that generates the counter electromotive force based on the input rotational speed Nm1 of the motor MG1 (step S180), and the high voltage system The booster circuit 55 is driven and controlled so that the voltage VH becomes the set target voltage VH * of the high voltage system (step S190), and the abnormal time drive control routine is terminated. Here, the target voltage VH * of the high voltage system is set as a target voltage setting of the high voltage system by previously determining the relationship between the rotational speed Nm1 of the motor MG1 and the target voltage VH * of the high voltage system through experiments and analysis. It is stored in the ROM 74 as a work map, and when the rotational speed Nm1 of the motor MG1 is given, the corresponding high voltage system target voltage VH * is derived and set from the stored map. This map shows the relationship between the high voltage system voltage VH and the generated power from the motor MG1 when the back electromotive force is generated for each rotation speed Nm1 of the motor MG1, and the high voltage system voltage VH is the voltage of the battery 50 (for example, 200 V or the like) and the highest boosted voltage (for example, 650 V or the like) that can be boosted by the booster circuit 55, and can be determined using a map determined in advance through experiments and analysis. FIG. 6 shows an example of a map representing the relationship between the high-voltage system voltage VH when the motor MG1 rotates at the rotational speed Nm1 and the generated power from the motor MG1 due to the generation of the counter electromotive force. In the figure, the magnitude of the generated power is expressed in a negative direction, and it can be seen that there is a minimum (maximum as an absolute value) point of the generated power of the motor MG1 with respect to the voltage VH of the high voltage system. . This is because the current Ia generated by the counter electromotive force generated in the motor MG1 is as follows using the voltage VH of the high voltage system, the number P of the pole pairs of the motor MG1, the rotational angular velocity ωm1, the counter electromotive constant φ, and each phase inductance L as an example. The generated power Pm1 expressed by the equation (3) and expressed by the equation (4) from the motor MG1 that generates the counter electromotive force can be expressed by the equation (3) as the equation (5). Based on what is considered. In Equation (3), the product of the number P of poles of the motor MG1, the rotational angular velocity ωm1, and the counter electromotive constant φ indicates the magnitude of the counter electromotive force generated by the motor MG1. As shown in the equation (5), when the voltage VH of the high voltage system is the product of the rotational angular velocity ωm1, the pole pair number P, the counter electromotive constant φ, and the value ½, it rotates at the rotational angular velocity ωm1 and the counter electromotive force is It can be seen that the generated electric power Pm1 from the motor MG1 is minimized (absolute value is maximized). In the embodiment, the motor MG1 that rotates at the rotational speed Nm1 is set by setting the target voltage VH * of the high voltage system using a map that is determined in advance through experiments and analysis rather than using a value that is calculated mathematically. The maximum generated power that can be generated is more reliably generated. Such control allows the engine 22 to operate independently at the maximum rotation speed Nemax with the gate of the inverter 41 shut off, and by adjusting the high voltage system voltage VH, the generated power of the motor MG1 associated with the counter electromotive force is increased as much as possible. By using the power generated by MG1 for driving the motor MG2 and charging the battery 50, it is possible to further increase the travel time and distance using only the power from the motor MG2.

  According to the hybrid vehicle 20 of the embodiment described above, the inverter 41 is gated when a predetermined abnormality occurs in which the motor MG1 cannot be normally driven within a range in which the gate of the inverter 41 driving the motor MG1 can be shut off. In the shut-off state, the engine 22 is independently operated at the maximum rotation speed Nemax, and the target voltage VH * of the high voltage system is set so that the maximum generated power that can be generated by the motor MG1 that rotates at the rotation speed Nm1 and generates the counter electromotive force is generated. The motor MG2 is controlled to drive the booster circuit 55 so that the high-voltage voltage VH becomes the set target voltage VH *, and to drive with the required torque Tr * within the input / output limits Win and Wout of the battery 50. Therefore, it is possible to continue traveling with only the power from the motor MG2 for a longer time.

  The hybrid vehicle 20 of the embodiment will be described as a process when a predetermined abnormality occurs in which the motor MG1 cannot be driven normally while the engine 22 is being operated, and the process is performed while the operation of the engine 22 is stopped. When the abnormality occurs, the drive control for the motor operation mode is continued. However, even if the operation of the engine 22 is stopped (fuel injection is stopped), the rotation of the engine 22 is stopped by the motoring by the motor MG1. When a predetermined abnormality occurs in a state where the abnormality is not performed, the abnormal-time drive control routine illustrated in FIG. 3 may be executed.

  In the hybrid vehicle 20 of the embodiment, the relationship between the rotational speed Nm1 of the motor MG1 and the target voltage VH * of the high voltage system is determined in advance through experiments and analysis and stored in the ROM 74 and input to the high voltage system target voltage setting map. The target voltage VH * of the high voltage system is set based on the rotational speed Nm1 of the motor MG1, but as shown in the equation (5), the input rotational speed Nm1 of the motor MG1 and a predetermined coefficient ( The product of the value 2π for converting the rotational speed Nm1 to the rotational angular velocity ωm1 and the product of the pole pair number P and the counter electromotive constant φ) and the value ½ may be set as the target voltage VH * of the high voltage system. Good.

  In the hybrid vehicle 20 of the embodiment, the target voltage VH * of the high voltage system is set so that as much as possible generated power is generated in the motor MG1 that generates the counter electromotive force based on the input rotational speed Nm1 of the motor MG1. Thus, generated power slightly smaller than the maximum generated power set based on the rotational speed Nm1 of the motor MG1 input as generated power in the motor MG1 that generates the starting power (for example, generated power that is 1 kW or 2 kW smaller) The target voltage VH * of the high voltage system may be set.

  In the hybrid vehicle 20 of the embodiment, the engine 22 is autonomously operated at the maximum rotational speed Nemax. However, the engine 22 may be autonomously operated at a predetermined rotational speed (for example, 4000 rpm, 4500 rpm, etc.) lower than the maximum rotational speed Nemax.

  In the hybrid vehicle 20 of the embodiment, when setting the torque command Tm2 * of the motor MG2, the input / output limits Win and Wout of the battery 50 are divided by the rotational speed Nm2 of the motor MG2 for the torque limits Tmin and Tmax that limit the temporary torque Tm2tmp. The torque Tm1b from the motor MG1 that rotates at the rotation speed Nm1 and generates the back electromotive force is set based on the target voltage VH * of the high voltage system and the rotation that is input with the set torque Tm1b. The torque limits Tmin and Tmax may be calculated using the following equations (6) and (7) based on the number Nm1 and the battery input / output limits Win and Wout, or the motor MG1 cannot be driven normally. In consideration of the abnormality, the torque limit Tm of the embodiment is used for the torque limit Tmin. n (= Win / Nm2) and its absolute value than the torque limit Tmax Example (= Wout / Nm2) for torque limit Tmax may be those calculated to be smaller by a predetermined value with similarly calculated.

Tmin = (Win-Tm1b ・ Nm1) / Nm2 (6)
Tmax = (Wout-Tm1b ・ Nm1) / Nm2 (7)

  In the hybrid vehicle 20 of the embodiment, the power of the motor MG2 is shifted by the reduction gear 35 and output to the ring gear shaft 32a. However, as illustrated in the hybrid vehicle 120 of the modified example of FIG. May be output to an axle (an axle connected to the wheels 64a and 64b in FIG. 7) different from an axle to which the ring gear shaft 32a is connected (an axle to which the drive wheels 63a and 63b are connected).

  In the hybrid vehicle 20 of the embodiment, the power of the engine 22 is output to the ring gear shaft 32a as the drive shaft connected to the drive wheels 63a and 63b via the power distribution and integration mechanism 30, but the modified example of FIG. As illustrated in the hybrid vehicle 220, a motor MG1 for power generation is connected to the engine 22, a motor MG2 is connected to the drive wheels 63a and 63b, and a battery 50 is connected to inverters 41 and 42 that drive the motors MG1 and MG2. May be connected.

  Moreover, it is not limited to what is applied to such a motor vehicle, It is good also as forms of vehicles other than motor vehicles, such as a train. Furthermore, it is good also as a form of the control method of such a vehicle.

  Here, the correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problems will be described. In the embodiment, the engine 22 corresponds to “internal combustion engine”, the motor MG1 corresponds to “generator”, the inverter 41 corresponds to “inverter circuit for generator”, the motor MG2 corresponds to “motor”, The inverter 42 corresponds to the “motor inverter circuit”, the battery 50 corresponds to the “storage means”, the booster circuit 55 corresponds to the “voltage adjustment means”, and the rotational position for detecting the rotational position of the rotor of the motor MG1. A motor ECU 40 that calculates the rotational speed Nm1 of the motor MG1 based on the detection sensor 43 and a signal from the rotational position detection sensor 43, or a rotational speed Ne of the engine 22 based on a crank position from a crank position sensor (not shown). Rotational speed Ne input by communication from engine ECU 24 and engine ECU 24 and rotational speed of ring gear 32 The hybrid electronic control unit 70 that calculates the rotational speed Nm1 of the motor MG1 based on r and the gear ratio ρ of the power distribution and integration mechanism 30 corresponds to “rotational speed acquisition means”, and the range in which the gate of the inverter 41 can be shut off When a predetermined abnormality occurs in which the motor MG1 cannot be driven normally, the required torque Tr * is output to the ring gear shaft 32a as the drive shaft and travels within the range of the input / output limits Win and Wout of the battery 50. The set torque command Tm2 * of the motor MG2 and the gate cut-off command of the inverter 41 are transmitted to the motor ECU 40, the maximum rotation speed Nemax is set to the target rotation speed Ne * for the independent operation of the engine 22, and transmitted to the engine ECU 24. The booster circuit 55 is driven with the target voltage VH * of the high voltage system set based on the rotation speed Nm1 of MG1. The hybrid electronic control unit 70 that executes the abnormal-time drive control routine of FIG. 3 to be controlled, the engine ECU 24 that controls the engine 22 with the target rotational speed Ne * for independent operation, and the gate of the inverter 41 based on the gate cutoff command are shut off. At the same time, the motor ECU 40 that controls the inverter 42 based on the torque command Tm2 * corresponds to an “abnormal control means”. The power distribution and integration mechanism 30 corresponds to “three-axis power input / output means”.

  Here, the “internal combustion engine” is not limited to an internal combustion engine that outputs power using a hydrocarbon fuel such as gasoline or light oil, and may be any type of internal combustion engine such as a hydrogen engine. The “generator” is not limited to the motor MG1 configured as a synchronous generator motor, and an induction motor or the like, which rotates at a rotational speed corresponding to the rotational speed of the internal combustion engine, generates a back electromotive force. Any type of generator can be used. The “generator inverter circuit” is not limited to the inverter 41, and any inverter circuit may be used as long as it drives the generator. The “motor” is not limited to the motor MG2 configured as a synchronous generator motor, and may be any type of motor as long as it can input and output power to the axle, such as an induction motor. The “motor inverter circuit” is not limited to the inverter 42, and any inverter circuit may be used as long as it drives the motor. The “storage means” is not limited to the battery 50 as a secondary battery, and any capacitor, such as a capacitor, can be used. The “voltage adjusting means” is not limited to the booster circuit 55, but between the low voltage system to which the power storage means is connected and the high voltage system to which the generator inverter circuit and the motor inverter circuit are connected. Any device may be used as long as it intervenes and adjusts the voltage of the high voltage system and exchanges power between the low voltage system and the high voltage system. The “rotational speed acquisition means” is not limited to the combination of the rotational position detection sensor 43 and the motor ECU 40 or the combination of the engine ECU 24 and the hybrid electronic control unit 70, and acquires the rotational speed of the generator. It does not matter as long as it does. The “abnormal control unit” is not limited to the combination of the hybrid electronic control unit 70, the engine ECU 24, and the motor ECU 40, and may be configured by a single electronic control unit. Further, the “control unit at the time of abnormality” is within the range of the input / output limits Win and Wout of the battery 50 when a predetermined abnormality occurs in which the motor MG1 cannot be driven normally within a range where the gate of the inverter 41 can be shut off. Then, the required torque Tr * is output to the ring gear shaft 32a as the drive shaft, and the inverter 42 is controlled by the torque command Tm2 * of the motor MG2, which is set to run, and the inverter 41 is shut off and the engine 22 is operated independently. It is limited to the one that sets the maximum rotation speed Nemax to the target rotation speed Ne * and controls the engine 22 to drive and control the booster circuit 55 with the target voltage VH * of the high voltage system set based on the rotation speed Nm1 of the motor MG1. It is not intended to be used for generators due to abnormalities in equipment or parts required for driving generators including inverter circuits for generators. When a predetermined abnormality occurs that prevents the generator from being driven normally within a range where the gate of the inverter circuit can be cut off, the internal combustion engine is operated independently at a predetermined number of revolutions with the inverter circuit for the generator cut off. The internal power engine and the inverter circuit for the generator are controlled, and the predetermined power range in the vicinity of the upper limit is set as the upper limit of the maximum generated power that can be generated by the generator that rotates at the obtained rotational speed and generates counter electromotive force. The voltage adjustment means is controlled so that the high voltage system target voltage is set based on the rotation speed acquired so that the generated power is generated by the generator and the high voltage system voltage is adjusted to the set target voltage. Any driving circuit may be used as long as it controls the inverter circuit for the motor so that the driving force based on the required driving force required for traveling is output from the motor. Further, the “3-axis power input / output means” is not limited to the power distribution and integration mechanism 30 described above, and four or more using a double pinion type planetary gear mechanism or a combination of a plurality of planetary gear mechanisms. The drive shaft connected to the axle, the output shaft of the internal combustion engine, and the rotating shaft of the generator, such as those connected to the shaft of the motor and those having a differential action different from the planetary gear such as a differential gear As long as the power is input / output to / from the remaining shafts based on the power input / output to / from any two of the three shafts, any configuration may be used.

  The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problem is the same as that of the embodiment described in the column of means for solving the problem. It is an example for specifically explaining the best mode for doing so, and does not limit the elements of the invention described in the column of means for solving the problem. That is, the interpretation of the invention described in the column of means for solving the problems should be made based on the description of the column, and the examples are those of the invention described in the column of means for solving the problems. It is only a specific example.

  The best mode for carrying out the present invention has been described with reference to the embodiments. However, the present invention is not limited to these embodiments, and various modifications can be made without departing from the gist of the present invention. Of course, it can be implemented in the form.

  The present invention can be used in the vehicle manufacturing industry.

1 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 20 according to an embodiment of the present invention. It is a block diagram which shows the outline of a structure of the electric drive system containing motor MG1, MG2. It is a flowchart which shows an example of the drive control routine at the time of abnormality performed by the electronic control unit for hybrids 70 of an Example. It is explanatory drawing which shows an example of the map for request | requirement torque setting. It is explanatory drawing which shows an example of the collinear diagram which shows the relationship of the rotation speed in the rotation element of the power distribution integration mechanism 30 when drive | working with the independent operation of the engine 22 in the state which interrupted the inverter 41. It is explanatory drawing which shows an example of the map showing the relationship between the voltage VH of a high voltage type | system | group when motor MG1 rotates with the rotation speed Nm1, and the electric power generated from motor MG1 accompanying generation | occurrence | production of a counter electromotive force. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 120 according to a modification. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 220 of a modified example.

Explanation of symbols

  20, 120, 220 Hybrid vehicle, 22 engine, 24 engine electronic control unit (engine ECU), 26 crankshaft, 28 damper, 30 power distribution integration mechanism, 31 sun gear, 32 ring gear, 32a ring gear shaft, 33 pinion gear, 34 carrier , 35 Reduction gear, 40 Motor electronic control unit (motor ECU), 41, 42 Inverter, 43, 44 Rotation position detection sensor, 45U, 45V, 46U, 46V Current sensor, 50 battery, 51 Temperature sensor, 52 Battery electronics Control unit (battery ECU), 54 power line, 54a positive bus, 54b negative bus, 55 booster circuit, 57, 58 capacitor, 57a, 58a voltage sensor, 60 gear mechanism, 62 differential gear, 63 , 63b Drive wheel, 64a, 64b wheel, 70 Hybrid electronic control unit, 72 CPU, 74 ROM, 76 RAM, 80 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 Brake pedal, 86 Brake pedal position sensor, 88 Vehicle speed sensor, MG1, MG2 motor, D11-D16, D21-D26, D31, D32 diode, T11-T16, T21-T26, T31, T32 transistor, L reactor.

Claims (6)

An internal combustion engine;
A generator that rotates at a rotational speed corresponding to the rotational speed of the internal combustion engine and generates a back electromotive force along with the rotational speed;
An inverter circuit for a generator that drives the generator;
An electric motor that can input and output power to the axle;
An inverter circuit for an electric motor that drives the electric motor;
Charge / discharge power storage means;
It is interposed between the low voltage system to which the power storage means is connected and the high voltage system to which the inverter circuit for the generator and the inverter circuit for the motor are connected, and adjusts the voltage of the high voltage system and the low voltage system. Voltage adjusting means for exchanging power between the system and the high voltage system;
A rotational speed acquisition means for acquiring the rotational speed of the generator;
There is a predetermined abnormality in which the generator cannot be normally driven within a range in which the gate of the inverter circuit for the generator can be shut off due to an abnormality in equipment or parts necessary for driving the generator including the inverter circuit for the generator. When it occurs, the internal combustion engine and the generator inverter circuit are controlled such that the internal combustion engine is operated independently at a predetermined rotational speed with the generator inverter circuit being gate-cut, and the acquired rotation is controlled. The obtained power is generated in the generator within a predetermined power range near the upper limit, with the maximum generated power that can be generated by the generator rotating by a number and generating counter electromotive force as an upper limit. A target voltage for the high voltage system is set based on the number of revolutions, and the voltage adjusting means is controlled so that the voltage of the high voltage system is adjusted to the set target voltage. And abnormality control means for controlling the inverter circuit for the motor so that the driving force based on the required driving force travels is outputted from the electric motor to be,
A vehicle comprising:   The abnormal-time control means predetermines and stores a rotational speed target voltage relationship, which is a relationship between the rotational speed of the generator and the target voltage of the high voltage system, by experiment or analysis, and the acquired rotational speed and the 2. The vehicle according to claim 1, wherein the vehicle is means for setting a target voltage of the high voltage system based on a stored rotational speed target voltage relationship.   The abnormal time control means, when the counter electromotive force generated in the generator is expressed as a product of the rotation speed of the generator and a predetermined coefficient, the acquired rotation speed, the predetermined coefficient, and the value 1 / 2. The vehicle according to claim 1, wherein the vehicle is a means for setting a product of 2 as a target voltage of the high voltage system.   The abnormality control means includes the internal combustion engine, the generator inverter circuit, the motor inverter circuit, and the voltage adjustment means when the predetermined abnormality occurs while the internal combustion engine is operating. The vehicle according to any one of claims 1 to 3, which is means for controlling.   Connected to the three shafts of the drive shaft connected to the axle, the output shaft of the internal combustion engine, and the rotating shaft of the generator, and the remainder based on the power input to and output from any two of the three shafts The vehicle according to any one of claims 1 to 4, further comprising three-axis power input / output means for inputting / outputting power to / from the shaft. An internal combustion engine, a generator that rotates at a rotational speed corresponding to the rotational speed of the internal combustion engine and generates a back electromotive force with the rotation, an inverter circuit for a generator that drives the generator, and power to the axle An electric motor capable of inputting / outputting, an inverter circuit for an electric motor that drives the electric motor, an electric storage means that can be charged / discharged, a low voltage system connected to the electric storage means, the inverter circuit for the generator, and the inverter circuit for the electric motor A vehicle control method comprising: a voltage adjusting unit that is interposed between a connected high voltage system and adjusts a voltage of the high voltage system, and exchanges power between the low voltage system and the high voltage system. Because
Obtaining the rotational speed of the generator,
There is a predetermined abnormality in which the generator cannot be normally driven within a range in which the gate of the inverter circuit for the generator can be shut off due to an abnormality in equipment or parts necessary for driving the generator including the inverter circuit for the generator. When it occurs, the internal combustion engine and the generator inverter circuit are controlled such that the internal combustion engine is operated independently at a predetermined rotational speed with the generator inverter circuit being gate-cut, and the acquired rotation is controlled. The obtained power is generated in the generator within a predetermined power range near the upper limit, with the maximum generated power that can be generated by the generator rotating by a number and generating counter electromotive force as an upper limit. A target voltage for the high voltage system is set based on the number of revolutions, and the voltage adjusting means is controlled so that the voltage of the high voltage system is adjusted to the set target voltage. Driving force based on the required driving force controls the inverter circuit for the motor to run is output from the electric motor to be,
Vehicle control method.

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