JP2008007018A - Motive power output device, vehicle equipped with the same, and control method of motive power output device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent on-failure of a transistor of an inverter 41 from affecting others by suppressing increase of a counter-electromotive force generated due to the rotation of a motor MG1 when the on-failure occurs. <P>SOLUTION: When any of the transistors of the inverter 41 fails in on-state, a revolving shaft 31a of the motor MG1 is fixed by a brake B1. Thereby, increase of the absolute value of engine speed of the motor MG1 can be suppressed, and increase of the counter-electromotive force generated due to rotation of the motor MG1 can be suppressed. As a result, increase of the current flowing through a closed circuit containing the on-failure transistor can be suppressed, and the influence of the on-failure of the transistor on others can be restrained. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a power output apparatus, a vehicle on which the power output apparatus is mounted, and a method for controlling the power output apparatus.

Conventionally, as this kind of power output device, an engine, a planetary gear mechanism in which a ring gear is connected to a torque output shaft connected to a wheel to which a carrier is connected to the engine, and a variable speed clutch to a sun gear of the planetary gear mechanism And a thing provided with the generator connected via the generator brake, the motor connected to the torque output shaft, and the battery which exchanges electric power with the generator and the motor is proposed. This device avoids engine stall by adjusting the variable speed clutch and operating the generator brake when the supply of power from the battery to the generator is interrupted while the engine is running. ing.
JP 2006-36202 A

  By the way, in such a power output device, it is desired to cope more appropriately when an abnormality occurs in a generator or an inverter that drives the generator. In a generator that generates counter electromotive force due to rotation, when the switching element of the inverter is turned on, even if the gate of the inverter is shut off, a closed circuit is formed by the switching element that failed to turn on and the winding coil of the generator. Current flows through the closed circuit. At this time, the current flowing through the closed circuit increases depending on the degree of rotation of the generator, and the switching element may be excessively heated to further damage the generator, the inverter, and the like.

  In the power output device of the present invention, the vehicle equipped with the power output device, and the control method of the power output device, the back electromotive force generated with the rotation of the first motor increases when an abnormality occurs in the first drive circuit. One of the purposes is to suppress this. Further, the power output device of the present invention, the vehicle equipped with the power output device, and the control method of the power output device suppress the damage of the first electric motor and the first drive circuit when an abnormality occurs in the first drive circuit. One of the purposes is to do.

  The power output apparatus of the present invention, the vehicle equipped with the power output apparatus, and the control method of the power output apparatus employ the following means in order to achieve at least a part of the above-described object.

The power output apparatus of the present invention is
A power output device that outputs power to a drive shaft,
An internal combustion engine;
Connected to three shafts of the output shaft of the internal combustion engine, the drive shaft, and a third shaft, and inputs / outputs power to / from the remaining shafts based on power input / output to / from any two of the three shafts Three-axis power input / output means for
A first electric motor capable of inputting / outputting power to / from the third shaft and generating a counter electromotive force with rotation;
A first drive circuit having a plurality of switching elements and driving the first electric motor using switching of the plurality of switching elements;
Rotation limiting means capable of limiting rotation of the third shaft;
When an abnormality occurs in which at least one of the plurality of switching elements of the first driving circuit has an abnormality, the third driving element is more than the normal time when all of the switching elements of the first driving circuit are normal. Control means for controlling the rotation limiting means so as to limit the absolute value of the rotational speed of the shaft;
It is a summary to provide.

  In the power output apparatus of the present invention, when an abnormality occurs in at least one of the plurality of switching elements of the first drive circuit, all of the plurality of switching elements of the first drive circuit are normal and normal. In contrast, the rotation limiting means is controlled so that the absolute value of the rotation speed of the third shaft is limited. Thereby, it is possible to suppress an increase in the rotational speed of the first electric motor when an abnormality occurs, and it is possible to suppress an increase in the back electromotive force generated with the rotation of the first electric motor.

  In such a power output apparatus of the present invention, the control means is a means for controlling when at least one of the plurality of switching elements of the first drive circuit is in an on state as a failure, when the abnormality occurs. You can also.

  Further, in the power output apparatus of the present invention, the first motor is a multiphase AC motor, and includes a plurality of current detection means for detecting a current flowing in each phase of the first motor, and the control means includes the first motor. It may be a means for controlling when the abnormality occurs when a current is detected by any of the plurality of current detection means while all of the plurality of switching elements of the drive circuit are being gated off. it can. By so doing, it is possible to more appropriately determine that an abnormality has occurred in at least one of the plurality of switching elements of the first drive circuit. Thus, it can be determined that an abnormality has occurred in any of the plurality of switching elements of the first drive circuit for the following reason. For example, when considering a case where any one of the plurality of switching elements of the first drive circuit has an on-failure, a closed circuit including the on-failure switching element is formed. When the first electric motor is rotating, a current flows through the closed circuit due to the counter electromotive force generated along with the rotation of the first electric motor. Therefore, it can be determined that an abnormality has occurred in the first drive circuit by detecting this current. Thus, when it is determined that an abnormality has occurred in the first drive circuit, the rotational speed limiting means is controlled so as to limit the absolute value of the rotational speed of the third shaft, thereby accompanying the rotation of the first electric motor. Thus, the back electromotive force generated can be suppressed from increasing, and the first motor and the first drive circuit can be further prevented from being damaged. As a result, it is possible to prevent other influences due to the abnormality of the first drive circuit.

  Further, in the power output apparatus of the present invention, the control means is configured to detect the absolute value of the rotational speed of the third shaft when the abnormality occurs and the absolute value of the rotational speed of the third shaft is larger than a predetermined value. It may be a means for controlling the rotation restricting means so that the value is restricted.

  Alternatively, the power output apparatus of the present invention may include a second electric motor that can input and output power to the drive shaft, and a second drive circuit that drives the second electric motor.

  The vehicle of the present invention is a power output device of the present invention according to any one of the above-described embodiments, that is, a power output device that basically outputs power to a drive shaft, and includes an internal combustion engine and an output of the internal combustion engine. Three-axis power input that is connected to three shafts of the shaft, the drive shaft, and the third shaft, and that inputs and outputs power to the remaining shafts based on power input to and output from any two of the three shafts Output means; a first electric motor capable of inputting / outputting power to / from the third shaft and generating counter electromotive force with rotation; a plurality of switching elements; and switching of the plurality of switching elements. Abnormality in which an abnormality has occurred in at least one of a first drive circuit that drives one electric motor, a rotation limiting unit that can limit rotation of the third shaft, and a plurality of switching elements of the first drive circuit Sometimes all of the plurality of switching elements of the first drive circuit And a control means for controlling the rotation restricting means so that the absolute value of the rotational speed of the third shaft is restricted as compared with the normal time when the vehicle is normal. It is summarized that it is connected to.

  Since the vehicle according to the present invention is equipped with the power output device of the present invention according to any one of the above-described aspects, the effect produced by the power output device according to the present invention, for example, occurs with the rotation of the first electric motor when an abnormality occurs. The same effects as the effect of suppressing the increase of the back electromotive force can be obtained.

The method for controlling the power output apparatus of the present invention includes:
Power is applied to the remaining shafts based on the internal combustion engine and the power input / output to / from any two of the three shafts connected to the three shafts of the output shaft, the drive shaft, and the third shaft of the internal combustion engine. A three-axis power input / output means for inputting / outputting, a first motor capable of inputting / outputting power to / from the third shaft and generating a counter electromotive force upon rotation, and a plurality of switching elements. A control method for a power output apparatus, comprising: a first drive circuit that drives the first electric motor using element switching; and a rotation limiting unit that can limit the rotation of the third shaft,
When an abnormality occurs in at least one of the plurality of switching elements of the first drive circuit, the rotational speed of the third shaft is higher than that in a normal state where all of the plurality of switching elements are normal. Controlling the rotation limiting means such that the absolute value is limited;
This is the gist.

  In this power output device control method of the present invention, when an abnormality occurs in at least one of the plurality of switching elements of the first drive circuit, all of the plurality of switching elements of the first drive circuit are normal. The rotation limiting means is controlled so that the absolute value of the rotation speed of the third shaft is limited as compared with a certain normal time. Thereby, it is possible to suppress an increase in the rotational speed of the first electric motor when an abnormality occurs, and it is possible to suppress an increase in the back electromotive force generated with the rotation of the first electric motor.

  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 a configuration of a hybrid vehicle 20 equipped with a power output apparatus 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 brake B1 connected to the rotation shaft 31a of the motor MG1, and a reduction gear 35 attached to a ring gear shaft 32a as a drive shaft connected to the power distribution and integration mechanism 30. And a motor MG2 connected to the reduction gear 35 and a hybrid electronic control unit 70 for controlling the entire power output apparatus.

  The engine 22 is an internal combustion engine that outputs power using a hydrocarbon-based fuel such as gasoline or light oil, and an engine electronic control unit (hereinafter referred to as an engine ECU) that receives signals from various sensors that detect the operating state of the engine 22. ) 24 is subjected to operation control such as fuel injection control, ignition control, intake air amount adjustment control and the like. 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 power distribution and integration mechanism 30 includes an external gear sun gear 31, an internal gear ring gear 32 disposed 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 and the brake B1 are 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 motor MG1 functions as a generator, power from engine 22 input from carrier 34 is distributed according to the gear ratio between sun gear 31 and ring gear 32, and input from carrier 34 when motor MG1 functions as an electric motor. The power from the engine 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. When brake B1 is turned on, rotating shaft 31a of motor MG1 is fixed. The brake B1 is not limited to a mechanically fixed one as long as the rotation shaft 31a of the motor MG1 can be fixed. For example, an electromagnetically locked one (for example, a motor) may be used. .

  FIG. 2 is a configuration diagram showing an outline of the configuration of the electric drive system centered on the motors MG1 and MG2. Each of the motors MG1 and MG2 is configured as a well-known PM-type synchronous generator motor including a rotor having a permanent magnet attached to an outer surface and a stator around which a three-phase coil is wound. Since the motors MG1 and MG2 are configured as synchronous generator motors, power can be generated by the motors MG1 and MG2 when power is input to the rotating shaft. That is, the motors MG1 and MG2 generate a counter electromotive force according to the rotation. Motors MG1 and MG2 exchange power with battery 50 through inverters 41 and 42. The power line 54 connecting the inverters 41 and 42 and the battery 50 is configured as a positive electrode bus and a negative electrode bus shared by the inverters 41 and 42, and the electric power generated by one of the motors MG1 and MG2 It can be consumed by a motor. Therefore, battery 50 is charged / discharged by electric power generated from one of motors MG1 and MG2 or insufficient electric power. The inverter 41 includes six transistors T1 to T6 and six diodes D1 to D6. Six transistors T1 to T6 are arranged in pairs so as to be on the source side and the sink side with respect to the positive and negative buses of the power line 54, and the three-phase coil of the motor MG1 ( (U phase, V phase, W phase) are connected. Six diodes D1 to D6 are connected in antiparallel to the six transistors T1 to T6, respectively. Therefore, a rotating magnetic field can be formed in the three-phase coil by controlling the ratio of the on-time of the transistors T1 to T6 that make a pair while the voltage is acting between the positive electrode bus and the negative electrode bus of the power line 54, The motor MG1 can be rotationally driven. The inverter 42 includes six transistors T7 to T12 and six diodes D7 to D12. Six transistors T7 to T12 are arranged in pairs so as to be on the source side and the sink side with respect to the positive electrode bus and the negative electrode bus of the inverter circuit 42, and a three-phase coil of the motor MG2 ( (U phase, V phase, W phase) are connected. Six diodes D7 to D12 are connected in antiparallel to the six transistors T7 to T12, respectively. Therefore, a rotating magnetic field can be formed in the three-phase coil by controlling the ratio of the on-time of the paired transistors T7 to T12 in a state where a voltage is acting between the positive electrode bus and the negative electrode bus of the power line 54, The motor MG2 can be driven to rotate. 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 that detect the rotational positions of the rotors of the motors MG1 and MG2, and the motors MG1 and MG2. The phase currents Iu1, Iv1, Iw1, Iu2, Iv2, Iw2, etc. from the current sensors 45U, 45V, 45W, 46U, 46V, 46W for detecting the phase current flowing in each phase of the three-phase coil are input, and the motor ECU 40 Is outputting a switching control signal to the transistors T1 to T6 and T7 to T12 of 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 battery 50 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. The battery ECU 52 also 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.

  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. The hybrid electronic control unit 70 includes an ignition signal from an ignition switch 80, a shift position SP from a shift position sensor 82 that detects the operation position of the shift lever 81, and an accelerator pedal position sensor 84 that detects the amount of depression 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. From the control unit 70, a drive signal to the brake B1 is output. 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 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 a drive control routine executed by the hybrid electronic control unit 70. This routine is repeatedly executed every predetermined time.

  When the drive control routine is executed, first, the CPU 72 of the hybrid electronic control unit 70 first determines the accelerator opening Acc from the accelerator pedal position sensor 84, the vehicle speed V from the vehicle speed sensor 88, the rotational speed Nm1, of the motors MG1, MG2. Nm2, input / output restrictions Win and Wout of the battery 50, processing of inputting data necessary for control such as phase currents Iu1, Iv1, and Iw1 flowing in the respective phases of the three-phase coil of the motor MG1 from the current sensors 45U, 45V, and 45W Execute (Step S100). Here, the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 are input from the motor ECU 40 by communication from those calculated based on the rotational positions of the rotors of the motors MG1 and MG2 detected by the rotational position detection sensors 43 and 44. To do. The input / output limits Win and Wout of the battery 50 are set based on the battery temperature Tb of the battery 50 detected by the temperature sensor 51 and the remaining capacity (SOC) of the battery 50 from the battery ECU 52 by communication. To do.

  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 current value having the largest absolute value among the phase currents Iu1, Iv1, Iw1 flowing in the respective phases of the three-phase coil of the motor MG1 is set as the maximum current I1 (step S120), and the inverter 41 of the motor MG1 is gated. It is determined whether or not it is shut off (step S130). If it is determined that the inverter 41 of the motor MG1 is not gate shut off, the brake B1 is turned off, that is, the motor MG1 is allowed to rotate (step S140). The maximum current I1 is compared with the threshold value Iref1 (step S150). Here, the threshold value Iref1 is used to determine whether or not an excessive current is flowing through the motor MG1 and the inverter 41, and is determined by the characteristics of the motor MG1 and the inverter 41.

  When the maximum current I1 is less than or equal to the threshold value Iref1, it is determined that no excessive current is flowing through the motor MG1 or the inverter 41, and the required power Pe * required for the vehicle is set (step S160). Here, the required power Pe * can be calculated as the sum of the required torque Tr * multiplied by the rotational speed Nr of the ring gear shaft 32a and the charge / discharge required power Pb * required by the battery 50 and the loss Loss. The rotation speed Nr of the ring gear shaft 32a can be obtained by multiplying the vehicle speed V by the conversion factor k, or can be obtained by dividing the rotation speed Nm2 of the motor MG2 by the gear ratio Gr of the reduction gear 35.

  Subsequently, the required power Pe * is compared with a threshold value Pref (step S170). The threshold value Pref is determined by the characteristics of the engine 22, and is set to a lower limit value of power that allows the engine 22 to be operated efficiently. When the required power Pe * is equal to or greater than the threshold value Pref, the target rotational speed Ne * and the target torque Te * of the engine 22 are set based on the required power Pe * (step S180). This setting is performed based on the operation line for efficiently operating the engine 22 and the required power Pe *. FIG. 5 shows an example of the operation line of the engine 22 and how the target rotational speed Ne * and the target torque Te * are set. As shown in the figure, the target rotational speed Ne * and the target torque Te * can be obtained from the intersection of the operation line and a curve with a constant required power Pe * (Ne * × Te *).

  Next, using the set target rotational speed Ne *, the rotational speed Nr (Nm2 / Gr) of the ring gear shaft 32a, and the gear ratio ρ of the power distribution and integration mechanism 30, the target rotational speed Nm1 of the motor MG1 is given by the following equation (1). * Is calculated and a torque command Tm1 * of the motor MG1 is calculated by equation (2) based on the calculated target rotational speed Nm1 * and the current rotational speed Nm1 (step S190). Here, Expression (1) is a dynamic relational expression for the rotating element of the power distribution and integration mechanism 30. FIG. 6 shows an example of a collinear diagram for dynamically explaining the rotational elements of the power distribution and integration mechanism 30. 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. Expression (1) can be easily derived by using this alignment chart. The two thick arrows on the R axis indicate that the torque Tm1 output from the motor MG1 acts on the ring gear shaft 32a and the torque Tm2 output from the motor MG2 acts on the ring gear shaft 32a via the reduction gear 35. Torque. Expression (2) is a relational expression in feedback control for rotating the motor MG1 at the target rotational speed Nm1 *. In Expression (2), “k1” in the second term on the right side is a gain of a proportional term. “K2” in the third term on the right side is the gain of the integral term.

Nm1 * = Ne * ・ (1 + ρ) / ρ-Nm2 / (Gr ・ ρ) (1)
Tm1 * = previous Tm1 * + k1 (Nm1 * -Nm1) + k2∫ (Nm1 * -Nm1) dt (2)

  When the target rotational speed Nm1 * and the torque command Tm1 * of the motor MG1 are thus calculated, the input / output limits Win and Wout of the battery 50 and the calculated torque command Tm1 * of the motor MG1 are multiplied by the current rotational speed Nm1 of the motor MG1. Torque limits Tmin and Tmax as upper and lower limits of the torque that may be output from the motor MG2 by dividing the deviation from the obtained power consumption (generated power) of the motor MG1 by the rotational speed Nm2 of the motor MG2 is expressed by the following equation (3). In addition, the temporary motor torque Tm2tmp as the torque to be output from the motor MG2 is calculated using the required torque Tr *, the torque command Tm1 *, and the gear ratio ρ of the power distribution and integration mechanism 30 (step S200). Calculated by equation (5) (step S210), and with the calculated torque limits Tmin and Tmax Setting the torque command Tm2 * of the motor MG2 as a value obtained by limiting the motor torque Tm2tmp (step S220). By setting the torque command Tm2 * of the motor MG2 in this way, the required torque Tr * output to the ring gear shaft 32a as the drive shaft is set as a torque limited within the range of the input / output limits Win and Wout of the battery 50. can do. Equation (5) can be easily derived from the collinear diagram of FIG. 6 described above.

Tmin = (Win-Tm1 * ・ Nm1) / Nm2 (3)
Tmax = (Wout-Tm1 * ・ Nm1) / Nm2 (4)
Tm2tmp = (Tr * + Tm1 * / ρ) / Gr (5)

  Thus, when the target engine speed Ne *, the target torque Te *, and the torque commands Tm1 *, Tm2 * of the motors MG1, MG2 are set, the target engine speed Ne * and the target torque Te * of the engine 22 are set in the engine ECU 24. The torque commands Tm1 * and Tm2 * for the motors MG1 and MG2 are transmitted to the motor ECU 40 (step S230), and the drive control routine is terminated. The engine ECU 24 that has received the target rotational speed Ne * and the target torque Te * performs fuel injection control in the engine 22 such that the engine 22 is operated at an operating point indicated by the target rotational speed Ne * and the target torque Te *. Controls such as ignition control. The motor ECU 40 that has received the torque commands Tm1 * and Tm2 * drives the transistors MG1 to T6 of the inverters 41 and 42 so that the motor MG1 is driven by the torque command Tm1 * and the motor MG2 is driven by the torque command Tm2 *. Switching control of T7 to T12 is performed.

  On the other hand, when the required power Pe * is less than the threshold value Pref in step S170, an operation control stop command for stopping the operation control of the engine 22 is transmitted to the engine ECU 24 (step S240), and the torque command Tm1 * of the motor MG1 is set. A value of 0 is set (step S250), the processes of steps S200 to S230 described above are executed, and the drive control routine is terminated. The engine ECU 24 that has received the operation control stop command stops the operation control of the engine 22.

  When the maximum current I1 is larger than the threshold value Iref1 in step S150, it is determined that an excessive current is flowing in the motor MG1 and the inverter 41, and a gate cutoff command for the inverter 41 of the motor MG1 is transmitted to the motor ECU 40 (step S290). Then, an operation control stop command for the engine 22 is transmitted to the engine ECU 24 (step S300), the processes of steps S200 to S230 described above are executed, and the drive control routine is terminated. The motor ECU 40 that has received the gate cutoff command turns off all the transistors T1 to T6 of the inverter 41 of the motor MG1.

  If it is determined in step S130 that the inverter 41 is gate-cut, the maximum current I1 is compared with the threshold value Iref2 (step S270). Here, the threshold value Iref2 is used to determine whether or not current is flowing in any of the three-phase coils of the motor MG1 even though the inverter 41 is gate-cut. It is determined by the characteristics of the inverter 41 and is set to a value smaller than the above-described threshold value Iref1, for example, a value of 0 or a value slightly larger than that. Since the inverter 41 is considered to be in a state where the gate is cut off, all the six transistors T1 to T6 are turned off. Therefore, the maximum current I1 is generally an approximate value 0. However, when any of the six transistors T1 to T6 is in the on state, for example, when considering that the transistor T1 is in the on state, it is attempted to turn off all of the transistors T1 to T6. The transistor T1 is turned on, and the transistor T1, the U-phase coil of the motor MG1, the V-phase or W-phase coil, the diode D2 or the diode D3, and the closed circuit of the transistor T1 are formed, and the motor MG1 rotates. When this occurs, a current flows through the closed circuit due to the counter electromotive force generated by the rotation. In the embodiment, in order to determine such an abnormality of the inverter 41, the maximum current I1 is compared with the threshold value Iref2 in a state where the inverter 41 is gate-cut off.

  When the maximum current I1 is less than or equal to the threshold value Iref2, it is determined that the inverter 41 is normal, the brake B1 is turned off, that is, kept in the off state (step S240), and the processing after step S250 is executed. Thus, when the gate shutoff of the transistors T1 to T6 of the inverter 41 of the motor MG1 is released by the processing of steps S260 and S230, the inverter 41 is not gate shut off in step S130 the next time the drive control routine is executed. It is determined.

  On the other hand, when the maximum current Ib is larger than the threshold value Iref2 in step S270, it is determined that an abnormality has occurred in the inverter 41, the brake B1 is turned on (step S280), and the processes after step S290 are executed. Now, consider the case where the inverter 41 is gate-cut and the maximum current Ib is larger than the threshold value Iref2, that is, when any of the transistors T1 to T6 of the inverter 41 is abnormal and a closed circuit is formed. FIG. 7 shows an example of a collinear diagram for explaining the relationship between the rotational speeds of the rotating elements of the power distribution and integration mechanism 30 when the inverter 41 is gate-cut off. In the figure, the solid line shows the relationship of the rotational speed when the brake B1 is turned on, and the broken line shows the relationship of the rotational speed when the brake B1 is turned off. When any of the transistors T1 to T6 of the inverter 41 is in the on state and fails, a closed circuit is formed as described above, and a current flows through the closed circuit due to the counter electromotive force generated by the rotation of the motor MG1. Here, considering the state in which the rotational speed Ne of the engine 22 is approximately 0 when the rotational speed Nr of the ring gear shaft 32a is relatively large as when traveling at a relatively high speed, the rotational speed of the motor MG1. When Nm1 is increased in the negative direction, a relatively large current flows through the closed circuit, the temperature of the motor MG1 and the inverter 41 increases, and the motor MG1 and the inverter 41 may be further damaged. In particular, in a vehicle in which the friction of the engine 22 is relatively large, it is difficult to increase the rotational speed Ne of the engine 22 due to the torque associated with the counter electromotive force generated by the rotation of the motor MG1, so the absolute value of the rotational speed Nm1 of the motor MG1 is It becomes difficult to reduce the size, and the risk of damaging the motor MG1, the inverter 41, and the like increases. On the other hand, if an abnormality occurs in the inverter 41 and a closed circuit is formed, if the brake B1 is turned on and the rotation speed Nm1 of the motor MG1 is fixed to a value of approximately 0, the counter electromotive force due to the rotation of the motor MG1 Since generation | occurrence | production can be suppressed, it can suppress that an electric current flows into a closed circuit, and can suppress that the motor MG1, the inverter 41, etc. are damaged more. That is, when any of the transistors T1 to T6 of the inverter 41 is in the on state and has a failure, the influence can be prevented from being given to others. In addition, the generation of torque associated with the counter electromotive force can be suppressed by turning on the brake B1 and suppressing the generation of the counter electromotive force. The torque associated with the counter electromotive force acts on the ring gear shaft 32a as a torque in the direction of decreasing the rotational speed of the ring gear shaft 32a as the drive shaft when the motor MG1 rotates at a negative rotational speed. By suppressing the generation of torque associated with the counter electromotive force, it is possible to travel with the power from the motor MG2 while suppressing a decrease in the traveling performance of the vehicle.

  According to the hybrid vehicle 20 of the embodiment described above, when an abnormality occurs in any of the transistors T1 to T6 of the inverter 41 of the motor MG1 and a closed circuit is formed, the brake B1 is turned on. It is possible to suppress the generation of counter electromotive force due to rotation and the flow of current to the closed circuit due to the counter electromotive force, thereby preventing other influences of transistor abnormality.

  In the hybrid vehicle 20 of the embodiment, the operation when the closed circuit is formed due to an abnormality in the inverter 41 while driving by outputting power to the ring gear shaft 32a as the drive shaft has been described. For example, even when the hybrid vehicle 20 of the embodiment is pulled and the ring gear shaft 32a is rotating, an abnormality occurs in the inverter 41 while outputting power to the shaft 32a. When the closed circuit is formed, the brake B1 may be turned on. Thereby, even when the hybrid vehicle 20 is being towed, it is possible to prevent other influences when the abnormality occurs in the inverter 41.

  In the hybrid vehicle 20 of the embodiment, when the inverter 41 of the motor MG1 is gate-cut, it is determined whether or not an abnormality has occurred in the inverter 41 using the maximum current I1. Alternatively, it may be determined whether or not an abnormality has occurred in the inverter 41 using the temperature of the motor MG1 or the temperature of the inverter 41.

  In the hybrid vehicle 20 of the embodiment, when the maximum current I1 is larger than the threshold value Iref2 in a state where the inverter 41 of the motor MG1 is shut off, the brake B1 is turned on so that the rotation speed Nm1 of the motor MG1 becomes substantially zero. However, the brake B1 is half-engaged so that the absolute value of the rotational speed Nm1 of the motor MG1 becomes small. It may be combined.

  In the hybrid vehicle 20 of the embodiment, when the maximum current I1 is larger than the threshold value Iref2 in a state where the inverter 41 of the motor MG1 is shut off, the vehicle is driven by the power from the motor MG2 with the brake B1 turned on. However, the vehicle may travel using the power from the engine 22 in addition to the power from the motor MG2 with the brake B1 turned on.

  In the hybrid vehicle 20 of the embodiment, the brake B1 is turned on regardless of the rotational speed Nm1 of the motor MG1 when the maximum current I1 is larger than the threshold value Iref2 with the inverter 41 of the motor MG1 being gated. The brake B1 may be turned on when the absolute value of the rotational speed Nm1 of the motor MG1 is larger than the threshold value Nref, and the brake B1 may be turned off when the absolute value of the rotational speed Nm1 of the motor MG1 is less than or equal to the threshold value Nref. Here, the threshold value Nref is used to determine whether or not the motor MG1 and the inverter 41 may be further damaged by the current flowing in the closed circuit due to the counter electromotive force generated by the rotation of the motor MG1. And the rating of the inverter 41. What is controlled in this way is that when the rotational speed Nm1 of the motor MG1 is relatively small, the current flowing through the closed circuit is also relatively small. Therefore, even if the brake B1 is not turned on, that is, the rotational speed Nm1 of the motor MG1. This is based on the fact that the motor MG1 and the inverter 41 are less likely to be damaged even if the value is not set to the approximate value 0.

  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 connected to an axle (an axle connected to the wheels 64a and 64b in FIG. 8) 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).

  Although the embodiment has been described as applied to the hybrid vehicle 20 including the engine 22, the power distribution and integration mechanism 30, the motors MG1 and MG2, and the brake B1, the present invention is applied to a vehicle that does not include the motor MG2 among these hardware configurations. It may be a thing.

  In addition, it is not limited to those applied to such hybrid vehicles, but is incorporated into non-moving equipment such as forms of power output devices mounted on moving bodies such as vehicles other than automobiles, ships, and aircraft, and construction equipment. A power output device may be used. Furthermore, it is good also as a form of the control method of such a power output device.

  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 power output apparatus and 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. 1 is a configuration diagram showing an outline of a configuration of an electric drive system that is mounted on a hybrid vehicle 20 and includes motors MG1, MG2, inverters 41, 42, a battery 50, and the like. It is a flowchart which shows an example of the drive control routine 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 a mode that an example of the operating line of the engine 22, and target rotational speed Ne * and target torque Te * are set. FIG. 4 is an explanatory diagram showing an example of a collinear diagram for dynamically explaining rotational elements of a power distribution and integration mechanism 30. It is explanatory drawing which shows an example of the alignment chart for demonstrating the relationship of the rotation speed of the rotation element of the power distribution integration mechanism 30 when the gate of the inverter 41 is interrupted | blocked. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 120 according to a modification.

Explanation of symbols

20, 120 Hybrid vehicle, 22 engine, 24 engine electronic control unit (engine ECU), 26 crankshaft, 28 damper, 30 power distribution and integration mechanism, 31 sun gear, 31a rotating shaft, 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 rotational position detection sensor, 50 battery, 51 temperature sensor, 52 battery electronic control unit (battery ECU), 54 Power line, 60 gear mechanism, 62 differential gear, 63a, 63b drive wheel, 64a, 64b wheel, 70 electronic control unit for hybrid, 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, 230 Counter rotor motor, 232 Inner rotor 234 Outer rotor, B1 brake, MG1, MG2 motor .

Claims (7)

A power output device that outputs power to a drive shaft,
An internal combustion engine;
Connected to three shafts of the output shaft of the internal combustion engine, the drive shaft, and a third shaft, and inputs / outputs power to / from the remaining shafts based on power input / output to / from any two of the three shafts Three-axis power input / output means for
A first electric motor capable of inputting / outputting power to / from the third shaft and generating a counter electromotive force with rotation;
A first drive circuit having a plurality of switching elements and driving the first electric motor using switching of the plurality of switching elements;
Rotation limiting means capable of limiting rotation of the third shaft;
When an abnormality occurs in which at least one of the plurality of switching elements of the first driving circuit has an abnormality, the third driving element is more than the normal time when all of the switching elements of the first driving circuit are normal. Control means for controlling the rotation limiting means so as to limit the absolute value of the rotational speed of the shaft;
A power output device comprising:   2. The power output apparatus according to claim 1, wherein the control unit is a unit that controls when at least one of a plurality of switching elements of the first drive circuit is in an on state and fails as the occurrence of the abnormality. 3. The power output device according to claim 1 or 2,
The first electric motor is a multiphase AC electric motor,
A plurality of current detection means for detecting a current flowing in each phase of the first electric motor;
The control means controls when a current is detected by any of the plurality of current detection means while the gates of all of the plurality of switching elements of the first drive circuit are being shut off as the occurrence of the abnormality. Power output device that is means.   When the abnormality occurs and the absolute value of the rotational speed of the third shaft is greater than a predetermined value, the control means is configured to limit the rotational speed of the third shaft so that the absolute value of the rotational speed of the third shaft is limited. The power output device according to any one of claims 1 to 3, wherein the power output device is means for controlling the power. The power output device according to any one of claims 1 to 4,
A second electric motor capable of inputting and outputting power to the drive shaft;
A second drive circuit for driving the second electric motor;
A power output device comprising:   A vehicle on which the power output device according to claim 1 is mounted and an axle is connected to the drive shaft. Power is applied to the remaining shafts based on the internal combustion engine and the power input / output to / from any two of the three shafts connected to the three shafts of the output shaft, the drive shaft, and the third shaft of the internal combustion engine. A three-axis power input / output means for inputting / outputting, a first motor capable of inputting / outputting power to / from the third shaft and generating a counter electromotive force upon rotation, and a plurality of switching elements. A control method for a power output apparatus, comprising: a first drive circuit that drives the first electric motor using element switching; and a rotation limiting unit that can limit the rotation of the third shaft,
When an abnormality occurs in at least one of the plurality of switching elements of the first drive circuit, the rotational speed of the third shaft is higher than that in a normal state where all of the plurality of switching elements are normal. Controlling the rotation limiting means such that the absolute value is limited;
Control method of power output device.