JP5807465B2 - Internal combustion engine torque fluctuation suppressing device, vehicle equipped with the same, and internal combustion engine torque fluctuation suppressing method - Google Patents

Description

  The present invention relates to a torque fluctuation suppressing device for an internal combustion engine that suppresses torque fluctuation of an internal combustion engine such as a truck engine and reduces gear rattling noise using a small-sized and high-power density electric motor, and a vehicle equipped with the same And a torque fluctuation suppressing method for an internal combustion engine.

  In general, in an internal combustion engine such as an engine, the output torque varies greatly during an intake stroke, a compression stroke, a combustion and expansion stroke, and an exhaust stroke. A mechanism is known that suppresses the fluctuation range of the combined torque of the internal combustion engine and the electric motor by using an electric motor to suppress the fluctuation (see, for example, Patent Document 1). In the conventional technology like this device, torque with high combustion and expansion strokes is suppressed by regenerative torque of the electric motor, and electric power is stored. The stored power is used in other processes, and the power balance of the motor becomes zero except for loss. Moreover, many electric motors that suppress torque fluctuations are arranged coaxially with the internal combustion engine, or are connected by pulleys and belts.

  Small and high power density motors used in the prior art tend to have high rotation and low torque, and need to be connected to the shaft of the internal combustion engine with a certain reduction ratio. For this reason, there are many cases in which pulleys and belts are used to connect to the shaft of the internal combustion engine. On the other hand, since a small-sized and high-power density electric motor can be realized by increasing the diameter or increasing the number of poles, there is an electric motor replaced with a conventional flywheel for smoothing the internal combustion engine torque (see, for example, Patent Document 2).

  When the former is adopted, there is a problem in transmission of high torque and transmission efficiency, and it is conceivable to connect with a gear as a solution, but in the case of gear drive, a rattle sound due to alternating torque when suppressing torque fluctuations of the internal combustion engine ( There are problems such as gear rattling noise) and gear durability. On the other hand, when the latter is used, there are many design changes, and it is difficult to adopt it in an internal combustion engine that produces a variety of products in small quantities.

  As an apparatus for reducing the rattle noise caused by the alternating torque when the torque fluctuation of the internal combustion engine is suppressed, there is an apparatus for reducing the rattle noise of the gear by controlling the motor generator to the power running side and the regeneration side (for example, Patent Document 3). reference). However, since the electric motor (motor generator) is controlled on the power running side and the regeneration side, there is a problem that the control becomes complicated. Further, it is necessary to invert the phase of the drive current on the power running side or the regeneration side, and a high-speed current change occurs, leading to a problem that the motor is lost.

JP 11-82094 A JP 11-44231 A JP 2008-162397 A

The present invention has been made in view of the above-described problems, and an object of the present invention is to suppress torque fluctuations of an internal combustion engine with high torque using a small-sized and high-power-density electric motor, and to reduce gears. An object of the present invention is to provide a torque fluctuation suppressing device for an internal combustion engine capable of suppressing gear rattling noise and improving gear durability, a vehicle equipped with the same, and a torque fluctuation suppressing method for the internal combustion engine.

The torque fluctuation suppressing device for an internal combustion engine according to the present invention for solving the above-mentioned object is a torque fluctuation suppressing device for an internal combustion engine, wherein the first electric motor and the second electric motor are connected to the battery via an inverter, and the first electric motor. Each of the electric motor and the second electric motor, and a gear meshing with a gear fixed to the crankshaft of the internal combustion engine, and when the inverter suppresses torque fluctuation of the internal combustion engine, the rotation direction of the crankshaft When the torque increases, the torque is reduced by the torque of the first motor and the second motor is caused to generate a torque opposite to the torque of the first motor, while the torque in the rotation direction of the crankshaft is increased. When the torque decreases, the torque is increased by the torque of the second motor, and the torque of the second motor is added to the first motor. The reverse torque was arranged to emit.

  According to this configuration, by using two electric motors each having a gear that meshes with a gear that rotates integrally with the crankshaft of the internal combustion engine and generating torques in opposite directions, the gear on the internal combustion engine side is It can be sandwiched by the gear on the motor side. Thereby, the torque fluctuation of the internal combustion engine can be suppressed, the rattle noise (tooth rattling noise) can be suppressed, and the durability of the gear can be improved.

  In addition, since the internal combustion engine and the electric motor are driven by gears, torque fluctuation suppression due to high torque can be performed. In addition, since the reduction ratio is given to the connection between the internal combustion engine and the electric motor, it is possible to use a small electric motor having a high output density. Furthermore, because of the gear drive, the rotor position of the electric motor and the crankshaft position of the internal combustion engine are synchronized, and control that requires the rotational shaft position, such as cylinder discrimination of the internal combustion engine, estimation of the stop position, sensorless drive of the electric motor, etc. It can be carried out.

In the torque fluctuation device for an internal combustion engine, when the inverter suppresses the torque fluctuation of the internal combustion engine, the first electric motor is dedicated to regeneration, while the second electric motor is dedicated to power running . when reducing the torque generated in the expansion stroke of the internal combustion engine in the regeneration suppression torque of first motor, wherein to generate a power running minute torque of the torque in the opposite direction from the first motor to the second electric motor, the second electric motor intake stroke of the internal combustion engine in a power running suppression torque, compression stroke, and when increasing the torque generated by the exhaust stroke, configuration Ru to generate regenerative minute torque of the torque in the opposite direction from the second electric motor to said first electric motor I made it.

  According to this configuration, torque fluctuation of the internal combustion engine can be suppressed, noise such as rattle noise can be prevented, and the durability of the gear can be improved. Moreover, since power running and regeneration are not repeated when considered with a single motor, controllability can be improved and efficiency can be improved compared to the case where alternating torque is generated using one electric motor. Can do. In this case, it is necessary to reverse the phase of the motor drive current for power running and regeneration. This is because a high-speed current change occurs and the current change may lead to a loss of the motor (generally referred to as iron loss).

  In addition, in the torque fluctuation suppressing device for an internal combustion engine described above, the rotor shaft of either the first motor or the second motor is formed as a hollow shaft, and the other rotor shaft is inserted through the hollow shaft. The first motor and the second motor are arranged so that the hollow shaft and the insertion shaft are on the same axis, and the gear is fixed to the hollow shaft, and the gear is fixed to the insertion shaft. Is configured to mesh with a gear fixed to the output shaft of the internal combustion engine. According to this configuration, the electric motors can be arranged in series, and space can be saved even if two electric motors are used.

Furthermore, in the above-described torque fluctuation suppressing device for an internal combustion engine, the first electric motor and the second electric motor are formed by electric motors having different efficiency maps with respect to rotational speed and output torque, and the inverter is provided with the torque of the internal combustion engine. When fluctuations are not suppressed, the first motor and the second motor are configured to generate torque in the same direction .

  According to this configuration, when it is not necessary to suppress the torque fluctuation of the internal combustion engine, it is possible to perform torque assist and regenerative braking at the time of starting the internal combustion engine with two motors with high efficiency. Moreover, the efficiency in a partial burden can be improved by using the motor from which the efficiency map with respect to a rotational speed and an output torque differs.

  A vehicle for solving the above problem is configured by mounting the torque fluctuation suppressing device for an internal combustion engine described above. According to this structure, the same effect as the above can be obtained.

An internal combustion engine torque fluctuation suppressing method for solving the above-described problem includes a torque fluctuation of an internal combustion engine in which a gear fixed to each of a first electric motor and a second electric motor is engaged with an engine gear fixed to a crankshaft of the internal combustion engine. When the torque fluctuation of the internal combustion engine is suppressed, when the torque in the rotation direction of the crankshaft increases, the torque is reduced by the torque of the first motor and the second motor is While generating torque opposite to the torque of the first electric motor, when the torque in the rotation direction of the crankshaft is decreased, the torque is increased by the torque of the second electric motor and the first electric motor is This is a method characterized by generating a torque opposite to the torque of the two motors .

Further, in the torque fluctuation suppression method for an internal combustion engine, when suppressing the torque fluctuation of the internal combustion engine, the first motor is dedicated to regeneration, while the second motor is dedicated to power running, and the regeneration of the first motor is performed. When the torque generated in the expansion stroke of the internal combustion engine is reduced by the suppression torque, the second motor generates a power running minute torque opposite to the torque of the first motor, and the power running suppression torque of the second motor is intake stroke of the internal combustion engine, the compression stroke, and when increasing the torque generated by the exhaust stroke, the first electric motor generates regenerative minute torque of the torque in the opposite direction from the second electric motor.

  According to the above method, the torque fluctuation of the internal combustion engine can be suppressed by using two electric motors, the rattle noise of the gear can be suppressed, and the durability of the gear can be improved. In addition, since the reduction ratio is given to the connection between the internal combustion engine and the electric motor, it is possible to use a small electric motor having a high output density.

  According to the present invention, it is possible to suppress the torque fluctuation of the internal combustion engine with a high torque by using a small and high power density motor, and to suppress the gear rattling noise and improve the durability of the gear. Can be made.

It is the figure which showed the torque fluctuation suppression apparatus of the internal combustion engine of 1st Embodiment which concerns on this invention. FIG. 2 is an enlarged view showing the gear mechanism of FIG. 1, (a) showing an expansion stroke, (b) showing an intake stroke, a compression stroke, and an exhaust stroke, (c) showing a regenerative brake, (d) It is the figure which showed torque assist. It is the figure which showed the torque fluctuation suppression torque and minute torque of the torque fluctuation suppression apparatus of the internal combustion engine of 1st Embodiment which concerns on this invention, (a) shows the generated torque of a regenerative motor, (b) is power running. It is the figure which showed the generated torque of an electric motor, and showed the alternating torque which match | combined the generated torque of a regenerative motor and a power running motor in (c). It is the figure which showed the output characteristic area | region of both the motors of the torque fluctuation suppression apparatus of the internal combustion engine of 1st Embodiment which concerns on this invention, (a) shows the output characteristic area | region of a regenerative motor, (b) It is the figure which showed the output characteristic area | region of the electric motor, and showed the area | region which match | combined the output characteristic area | region of both the motors to (c). It is the figure which showed the torque fluctuation suppression apparatus of the internal combustion engine of 2nd Embodiment which concerns on this invention. It is the figure which showed the torque fluctuation suppression apparatus of the internal combustion engine of 3rd Embodiment which concerns on this invention.

  Hereinafter, a torque fluctuation suppressing device for an internal combustion engine, a vehicle equipped with the same, and a torque fluctuation suppressing method for an internal combustion engine according to an embodiment of the present invention will be described with reference to the drawings.

  First, a torque fluctuation suppressing apparatus for an internal combustion engine according to a first embodiment of the present invention will be described with reference to FIG. The torque fluctuation suppressing device 1 includes a regenerative motor (first motor) 10, a powering motor (second motor) 20, a gear mechanism 30, an ECU (control device) 40, an inverter (power converter) 41, and a battery (power storage device). 42 is provided.

  The regenerative motor 10 is a permanent magnet synchronous motor having six armatures 11 (two in the figure, the remaining four are omitted) as stators and permanent magnets 12 as rotors. Similarly, the power running motor 20 is a permanent magnet synchronous motor including six armatures 21 and permanent magnets 22. In addition to the above configuration, the permanent magnet 22 which is a rotor of the power running motor 20 is formed in a hollow shape so as to be inserted through the insertion shaft 32.

  These electric motors 10 and 20 are set so that the torque due to regeneration of the regenerative motor 10 and the torque due to power running of the power running motor 20 are in opposite directions. In addition, both of these electric motors 10 and 20 can use electric motors of a well-known technology, and are not limited to the above-described configuration, and induction motors and reluctance motors can be used.

  In the past, the total output of one or two motors has been 8 kW or less, and many belt-driven systems have been proposed. However, the outputs of both the above-mentioned motors 10 and 20 are the same as the conventional one, preferably one Is preferably 4 kW or more. According to this, torque fluctuation of the engine 2 can be suppressed with high torque.

  In addition, in order to reduce the size of both the electric motors 10 and 20, it is preferable to use one having a high rotation speed. Preferably, the rated rotational speed is about 6000 rpm or higher and the electrical maximum rotational speed capable of generating torque is 10,000 rpm or higher. For example, when the maximum rotation speed of the engine 2 is suppressed to 4000 rpm and the reduction ratio is 3, the small motors 10 and 20 with high rotation have a mechanical maximum rotation speed (no torque is generated). 12000 rpm is required.

  The gear mechanism 30 includes an engine gear 31, an insertion shaft 32, a regenerative gear 33, a hollow shaft 34, and a power running gear 35. The engine gear 31 is a gear fixed to the crankshaft 3 of the engine 2, and a regenerative gear 33 and a power running gear 35 are arranged so as to mesh with the engine gear 31.

  The hollow shaft 34 is joined to the permanent magnet 22 as a rotor, and is formed in a hollow shape, and a power running gear 35 is fixed to the hollow shaft 34. Further, the insertion shaft 32 is joined to the permanent magnet 12 that is a rotor, and is inserted through the hollow permanent magnet 22 and the hollow shaft 34 of the powering electric motor 20. A regenerative gear 33 is fixed to the insertion shaft 32.

  The gear mechanism 30 further adds a gear between the engine gear 31 and the regenerative gear 33 or the power running gear 35 in order to give an arbitrary reduction ratio to the rotation of the engine 2 and the rotation of the electric motors 10 and 20. Also good.

As described above, the torque fluctuation suppressing device 1 according to the embodiment of the present invention is configured to mesh the regenerative gear 33 and the power running gear 35 with the same engine gear 31. According to the configuration in which the electric motors 10 and 20 and the crankshaft 3 of the engine 2 are connected via the gear mechanism 30, the engine 2 and the electric motors 1
The connection of 0 and 20 can have a reduction ratio (gear ratio). Therefore, a small and high power density electric motor can be used. Further, because of the gear drive, torque fluctuations of the engine 2 due to high torque can be suppressed.

  Furthermore, because of the gear drive, both the motors 10 and 20, the rotor position, and the crankshaft 3 position of the engine 2 are synchronized, the cylinder discrimination of the engine 2, the stop position estimation, the sensorless drive of the both motors 10 and 20, etc. The control requiring the rotation axis position can be performed by judging from the rotor positions of both the electric motors 10 and 20. This rotor position can be detected by an inverter 41 connected to both electric motors 10 and 20.

  Both the electric motors 10 and 20 are connected to a battery 42 via an inverter 41. As the inverter 41 and the battery 42, an inverter and a battery of a known technique can be used. The inverter 41 is preferably an inverter that can change the rotational speeds of both the electric motors 10 and 20, and more preferably a VVVF (variable voltage variable frequency control) inverter.

  The ECU 40 is a control device called an engine control unit, and is responsible for controlling the entire power plant including the transmission by an electric circuit. The microcontroller also controls the engine and performs overall electrical control. In an automatic vehicle, the ECU 40 stores the optimum control value in every driving state, detects the occasional state with a crank angle sensor, a cam angle sensor, etc., and stores the data among the stored data by the input signals from these sensors. The optimum value is selected from each and each mechanism is controlled. In the embodiment of the present invention, the output torques of both electric motors 10 and 20 are controlled.

  Next, a torque fluctuation suppressing method of the engine 2 will be described with reference to FIG. When a large torque T1 is generated in the rotation direction of the crankshaft 3 due to the expansion stroke of the engine 2, as shown in FIG. 2A, the regenerative motor 10 generates a regenerative suppression torque Tr1 that suppresses torque fluctuations. . Thereby, the torque fluctuation | variation by the torque T1 increased in the rotation direction of the crankshaft 3 is suppressed. At the same time, the power running motor 20 is caused to generate a minute power running minute torque Ti1 in the direction opposite to the regeneration suppression torque Tr1, and the engine gear 31 is sandwiched between the regeneration gear 33 and the power running gear 35.

  At this time, the tooth surface S 1 of the engine gear 31 is in contact with the regenerative gear 33, and the tooth surface S 2 of the engine gear 31 is in contact with the power running gear 35. When the power running gear 35 comes into contact with the tooth surface S2 by the power running minute torque Ti1, the tooth surface on the same side as the tooth surface S1 of the engine gear 31 is always in contact with the regenerative gear 33.

  On the other hand, when an insufficient torque T2 is generated in the rotation direction of the crankshaft 3 in the rotation direction of the crankshaft 3 due to the intake stroke, compression stroke, and exhaust stroke of the engine 2, FIG. As shown in FIG. 4, the power running motor 20 is caused to generate a power running suppression torque Ti2 that suppresses torque fluctuation. As a result, a sufficient torque is generated by combining the torque T2 and the power running suppression torque Ti2 in the rotation direction of the crankshaft 3. At the same time, the regenerative motor 10 is caused to generate a small regenerative minute torque Tr2 in the direction opposite to the power running suppression torque Ti2, and the engine gear 31 is sandwiched between the power running gear 35 and the regenerative gear 33.

  At this time, the tooth surface S <b> 2 of the engine gear 31 is in contact with the power running gear 35, and the tooth surface S <b> 1 of the engine gear 31 is in contact with the regenerative gear 33. The regenerative gear 33 comes into contact with the tooth surface S1 by the regenerative minute torque Tr2, so that the tooth surface on the same side as the tooth surface S2 of the engine gear 31 is always in contact with the power running gear 35.

  When regenerative braking is performed when there is no torque fluctuation of the engine 2 as described above, a regenerative torque Tr3 in the opposite direction to the torque T3 of the engine 2 is generated in the regenerative motor 10 as shown in FIG. Further, the regenerative torque Ti3 in the direction opposite to the torque T3 of the engine 2 is generated in the power running motor 20. At this time, both the regenerative gear 33 and the power running gear 35 are in contact with the tooth surface S1 of the engine gear 31.

  As shown in FIG. 2 (d), when the torque T4 of the engine 2 is small, such as when the engine 2 is started, and the crankshaft 3 cannot be sufficiently rotated, the torque is supplied to the regenerative motor 10. A power running torque Tr4 in the same direction as T4 is generated, and the power running motor 20 similarly generates a power running torque Ti4. At this time, both the regenerative gear 33 and the power running gear 35 are in contact with the tooth surface S <b> 2 of the engine gear 31.

  According to the above operation, when the torque fluctuation of the engine 2 is large, the torque fluctuations of the engine 2 are generated by causing the two electric motors 10 and 20 to generate mutually opposite torques (Tr1 and Ti1, Tr2 and Ti2). Further, by sandwiching the engine gear 31 of the engine 2 between the regenerative gear 33 and the power running gear 35, the same tooth surface of the engine gear 31 is always in contact with either the regenerative gear 33 or the power running gear 35. Therefore, it is possible to suppress the rattle sound (gear noise) of the gear and improve the durability of the gear mechanism 30.

  In addition, since each of the regenerative motor 10 and the power running motor 20 does not repeat power running and regeneration when suppressing torque fluctuations of the engine 2, the controllability of both the motors 10 and 20 can be improved. In addition, iron loss of the motor can be prevented and efficiency can be improved as compared with the case where torque fluctuation is suppressed by repeating regeneration and power running.

  Here, the calculation method of the output torque of both the electric motors 10 and 20 performed by ECU40 is demonstrated. The torque waveform obtained by this calculation method is shown in FIG. First, a step of calculating the rotational speed N of the engine 2 is performed. The rotational speed N of the engine 2 is calculated by calculating the rotational speed of the rotor of the regenerative motor 10 or the power running motor 20 and using the rotational speed and the reduction ratio (gear ratio). It can be calculated by a method of providing and measuring.

  Next, a step of calculating a sine wave fundamental frequency λ is performed from the calculated rotation speed N of the engine 2 using the following mathematical formulas (1) and (2).

  Once the sine wave fundamental frequency λ has been calculated, the step of acquiring the fuel injection amount q of the engine 2 is then performed. This fuel injection amount q is the amount of fuel that is injected into each cylinder by an injector (not shown) provided in the engine 2. The fuel injection amount q is controlled by the ECU 40, and the value is used as it is. Next, torques T1 and T2, which are the peak torque fluctuations of the engine 2 in accordance with the fuel injection quantity q, are determined. The torques T1 and T2 are set values determined in advance by the value of the fuel injection amount q, and are stored in the ECU 40.

  Next, a step of calculating the regeneration suppression torque Tr1 and the power running suppression torque Ti2 is performed. A difference torque ΔT1 between one-cycle average torque T0 generated when fuel is injected at a fuel injection amount q and torque T1, which is a peak of torque fluctuation, is calculated. The regeneration suppression torque Tr1 is calculated as a torque that cancels the differential torque ΔT1. Similarly, the power running suppression torque Ti2 is calculated from the difference between the average torque T0 and the torque T2. Thus, the calculation of the regeneration suppression torque Tr1 and the power running suppression torque Ti2 that suppress the torque fluctuation of the engine 2 is completed.

  Next, a step of calculating the acceleration / deceleration ω2 of one cycle (intake, compression, expansion, and exhaust stroke) of the engine 2 is performed. This acceleration / deceleration ω2 is calculated from the time (referred to as the number of controller clocks) required for one pulse of the regenerative motor 10, the power running motor 20, or a pulse detection type angle sensor such as a crank angle sensor.

  Next, a step of calculating regenerative minute torque Tr2 and powering minute torque Ti1 is performed. Here, when the inertia moment of the regenerative motor 10 is Ir, the angular acceleration is ω2r ′, the friction torque is Tfr, the inertia moment Ii of the power running motor 20 is the angular acceleration is ω2i ′, and the friction torque is Tfi, the equation of motion of the rotating system Thus, the following mathematical formulas (3) and (4) are established.

  Here, the friction torques Tfr and Tfi can be estimated from the properties of the electric motors 10 and 20. Therefore, the maximum acceleration / deceleration of the engine 2 or more, that is, the angular acceleration ω2r ′ of the regenerative motor 10 and the angular acceleration ω2i ′ of the power running motor 20 are greater than or equal to the maximum acceleration in one cycle of the engine 2 or the maximum decrease in one cycle. The regenerative minute torque Tr2 and the powering minute torque Ti1 that satisfy the above formulas (3) and (4) are calculated so as to be less than the speed.

  The regenerative minute torque Tr2 and the power running minute torque Ti1 calculated as described above are necessary and sufficient torques that the same side tooth surface of the engine gear 31 is always in contact and the rattle noise of the gear can be reduced. The above calculation method is possible because the inertia moments Ir and Ii and the friction torques Tfr and Tfi of both the electric motors 10 or 20 are extremely smaller than those of the engine 2.

  The torque waveform shown in FIG. 3A can be calculated from the sine wave fundamental frequency λ, the torque fluctuation suppressing torque Tr1, and the minute torque Tr2 of the regenerative motor 10 calculated by the above method. Further, the torque waveform shown in FIG. 3B can be calculated from the sine wave fundamental frequency λ, the torque fluctuation suppressing torque Ti2, and the minute torque Ti1 of the power running motor 20. The total torque obtained by combining the torques generated by the regenerative motor 10 and the power running motor 20 is as shown in FIG. 3C, and this is an alternating torque that suppresses torque fluctuations of the engine 2.

According to the above calculation method, with respect to the regenerative motor 10 that generates the regenerative suppression torque Tr1 that decreases the torque that increases due to the expansion stroke of the engine 2, the other power running motor 20 has a power running micro torque Ti1 in the opposite direction. Is generated. Thereby, the same side tooth surface of the engine gear 31 can always be in contact with the regenerative gear 33.

  In contrast to the powering motor 20 that generates the powering suppression torque Ti2 that increases the torque that decreases due to the intake stroke, the compression stroke, and the exhaust stroke of the engine 2, the other regenerative motor 10 has a regenerative minute torque in the opposite direction. Tr2 is generated. Thereby, the same side tooth surface of the engine gear 31 can always be in contact with the power running gear 35.

  In addition, the number of rotations of the engine 2 and the acceleration / deceleration of one cycle necessary for the method of calculating the regeneration suppression torque Tr1 and the power running suppression torque Ti2 and the regeneration minute torque Tr2 and the power running minute torque Ti1 are set to the regenerative electric motor 10. Alternatively, the power running motor 20 can be used as a pulse detection type angular velocity sensor without adding a special device.

  The above calculation method is not limited to the above calculation method as long as a torque waveform as shown in FIG. 3 can be calculated, but the above calculation method is preferable because it requires the minimum number of sensors and is easy to calculate.

  Next, the output characteristic area of both motors of the torque fluctuation suppressing device 1 will be described with reference to FIG. In the torque fluctuation suppressing device 1 described above, the regenerative motor 10 and the power running motor 20 have main operation regions in different output characteristic regions. The regenerative motor 10 has a main operation area a in the output characteristic area shown in FIG. 4A, and the powering motor 20 has a main operation area b in the output characteristic area shown in FIG. 4B. . When the regenerative motor 10 and the power running motor 20 are considered as a single motor, the torque fluctuation suppressing device 1 has a main operation region c in the output characteristic region shown in FIG.

  According to this configuration, when it is not necessary to suppress the torque fluctuation of the engine 2, the engine 2 is considered in consideration of the main operation region (the efficiency of the two electric motors 10 or 20) shown in FIG. By applying torque assist and regenerative braking at the time of starting, efficiency at a partial load can be improved. Thereby, energy efficiency can be improved.

  In this case, for example, the regenerative motor 10 is a concentrated winding motor so that the high torque and low rotation speed region in the output characteristic region becomes the main operation region a, and the power running motor 20 is in the low torque high rotation region in the output characteristic region. The distributed winding motor is set so that the number of regions become the main operation region b. Preferably, the main operation area a and the main operation area b are distributed as close as possible.

  Next, torque fluctuation suppressing devices according to second and third embodiments of the present invention will be described with reference to FIGS. The difference between the torque fluctuation suppressing device 4 of the second embodiment according to the present invention and the torque fluctuation suppressing device 5 of the third embodiment according to the present invention is only the arrangement of both electric motors.

  As shown in FIG. 5, the torque fluctuation suppressing device 4 includes a regenerative motor 50, a power running motor 60, and a gear mechanism 70. The regenerative motor 50 includes six armatures 51 (two in the figure, the remaining four are omitted) as stators and a permanent magnet 52 as a rotor, and the power running motor 60 is similarly a stator. Armature 61 and a permanent magnet 62 as a rotor. The gear mechanism 70 includes an engine gear 71, a regenerative shaft 72, a regenerative gear 73, a power running shaft 74, and a power running gear 75. A regenerative gear 73 and a power running gear 75 are arranged above and below the engine gear 71 so as to straddle the engine gear 71 fixed to the crankshaft 3 in the vertical direction of the drawing, and mesh with the engine gear 71 respectively.

According to this configuration, one of the motors and the rotating shaft are not formed in a hollow shape, and a substantially identical motor can be used. Although the installation space is larger than that of the torque fluctuation suppressing device 1 according to the first embodiment of the present invention, the same operational effects can be obtained.

  As shown in FIG. 6, the torque fluctuation suppressing device 5 spans the regenerative motor 50 configured as described above across the engine gear 71 in the horizontal direction of the drawing, and the regenerative shaft 72 and the power running shaft 74 are on the same axis. Arrange as follows. Even with this configuration, the same effect as described above can be obtained.

  The torque fluctuation suppressing device 1, 4 or 5 described above can be applied to a hybrid vehicle using both the electric motor and the engine as drive sources. Moreover, even if it is not a hybrid vehicle, it can be applied by adding another electric motor to a vehicle equipped with an electric motor as a starter. A vehicle equipped with these torque fluctuation suppressing devices 1, 4, or 5 can suppress engine torque fluctuations and reduce gear rattle noise.

  Further, the configuration of the engine is not limited and can be applied to a diesel engine and a gasoline engine.

  INDUSTRIAL APPLICABILITY The torque fluctuation suppression device for an internal combustion engine according to the present invention can suppress the torque fluctuation of the internal combustion engine with a small and high power density motor, and can reduce the rattle noise of the gear and improve the durability of the gear. Therefore, it can be used for a vehicle such as a truck equipped with a diesel engine having a particularly high in-cylinder pressure and large engine torque fluctuation.

1, 4, 5 Torque fluctuation suppressing device 2 Engine (internal combustion engine)
3 Crankshaft 10 Regenerative motor (first motor)
20 Powering motor (second motor)
30 Gear mechanism 40 ECU (control device)
41 Inverter (Power converter)
42 battery (power storage device)

Claims (7)

In the torque fluctuation suppressing device for an internal combustion engine,
A first electric motor and a second electric motor connected to the battery via an inverter, and a gear meshing with a gear fixed to the crankshaft of the internal combustion engine in each of the first electric motor and the second electric motor ,
When the inverter suppresses torque fluctuations of the internal combustion engine, when the torque in the rotation direction of the crankshaft increases, the torque is reduced by the torque of the first motor and the second motor is supplied with the second torque. While generating torque opposite to the torque of one motor, when the torque in the rotation direction of the crankshaft is decreased, the torque is increased by the torque of the second motor and the second motor is supplied to the first motor. A torque fluctuation suppressing device for an internal combustion engine, characterized in that a torque having a direction opposite to that of the engine is generated . When the inverter suppresses torque fluctuations of the internal combustion engine, the first motor is dedicated to regeneration, while the second motor is dedicated to power running,
Wherein when reducing the torque generated in the expansion stroke of the internal combustion engine by regeneration reducing torque of the first electric motor to generate a torque in the opposite direction from power running minute torque of the first electric motor to the second electric motor,
Intake stroke of the internal combustion engine in a power running suppression torque of the second electric motor, a compression stroke, and when increasing the torque generated by the exhaust stroke, the regenerative minute torque of the torque in the opposite direction from the second electric motor to said first electric motor torque fluctuation suppressing device for an internal combustion engine according to claim 1, characterized in that it has a configuration in which Ru is generated. The rotor shaft of one of the first motor and the second motor is formed with a hollow shaft, and the other rotor shaft is formed with an insertion shaft that is inserted through the hollow shaft,
Arranging the first electric motor and the second electric motor so that the hollow shaft and the insertion shaft are on the same axis;
A gear which is fixed to said hollow shaft, a gear that is fixed to the insertion axis, the torque fluctuation suppressing an internal combustion engine according to claim 1 or 2, characterized in that the gear meshes were fixed to the output shaft of the internal combustion engine apparatus. When the first motor and the second motor are formed of motors having different efficiency maps for rotational speed and output torque, and the inverter does not suppress torque fluctuations of the internal combustion engine, the first motor and the second motor The torque fluctuation suppressing device for an internal combustion engine according to any one of claims 1 to 3, wherein the second motor is configured to generate torque in the same direction.   A vehicle equipped with the torque fluctuation suppressing device for an internal combustion engine according to any one of claims 1 to 4. A torque fluctuation suppression method for an internal combustion engine in which a gear fixed to each of a first motor and a second motor is engaged with a gear fixed to a crankshaft of the internal combustion engine,
When the torque fluctuation of the internal combustion engine is suppressed, when the torque in the rotation direction of the crankshaft increases, the torque is reduced by the torque of the first motor and the second motor is the torque of the first motor. While the torque in the rotation direction of the crankshaft decreases, the torque is increased by the torque of the second motor and the first motor is opposite to the torque of the second motor. A torque fluctuation suppressing method for an internal combustion engine, characterized by generating torque in a direction . When suppressing torque fluctuations of the internal combustion engine, the first motor is dedicated to regeneration, while the second motor is dedicated to power running,
When the torque generated in the expansion stroke of the internal combustion engine is reduced by the regeneration suppression torque of the first motor, the second motor generates a power running minute torque opposite to the torque of the first motor;
When the torque generated in the intake stroke, the compression stroke, and the exhaust stroke of the internal combustion engine is increased by the power running suppression torque of the second motor, the regenerative minute torque in which the first motor is opposite to the torque of the second motor. The torque fluctuation suppressing method for an internal combustion engine according to claim 6, wherein: