JP3978930B2 - Hybrid vehicle and control method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce torque shocks in a hybrid vehicle. SOLUTION: In a hybrid vehicle, a motor MG1 is coupled with a sun gear of a planetary gear, an engine is coupled with a planetary gear, and a motor MG2 and a shaft are coupled with a ring gear. A torque sensor 167 for detecting torque generated from the motor MG1 to the sun gear is provided. In the hybrid vehicle, the motor MG1 and the engine are operated according to the required torque. The motor MG2 compensates for the output torque from the motor MG1 and the engine to generate required torque at the shaft. The output torque is specified on the basis of the value detected by the torque sensor 167. Even when the actual output torque is affected by the influence of inertia and different from a torque command of the motor MG1 at a transient time, the output is compensated accurately and torque shocks are reduced.

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a hybrid vehicle having an engine and an electric motor and capable of traveling using at least power output from the engine as a power source and a control method thereof.
[0002]
[Prior art]
In recent years, hybrid vehicles including an engine and an electric motor have been proposed. Various configurations have been proposed as such hybrid vehicles, and one of them is a parallel hybrid vehicle. In a parallel hybrid vehicle, both engine power and motor power can be transmitted to the axle. A configuration example of a parallel hybrid vehicle is shown in FIG.
[0003]
The hybrid vehicle in FIG. 1 includes an engine 150 and electric motors MG1 and MG2. The three are mechanically coupled via the planetary gear 120. Planetary gear 120 is also called a planetary gear and has three rotating shafts coupled to the gears shown below. The gears constituting the planetary gear 120 are a sun gear 121 that rotates at the center, a planetary pinion gear 123 that revolves while rotating around the sun gear, and a ring gear 122 that rotates at the outer periphery thereof. The planetary pinion gear 123 is pivotally supported by the planetary carrier 124. In the hybrid vehicle of FIG. 1, the engine 150 is coupled to the planetary carrier 124. Electric motor MG1 is coupled to sun gear 121. Electric motor MG2 is coupled to ring gear 122. Ring gear 122 is coupled to drive shaft 112 and is coupled to axle 116 via differential gear 114.
[0004]
In the hybrid vehicle having such a configuration, the power output from the engine is distributed to two by the planetary gear 120. A part of it is transmitted to the drive shaft 112 as mechanical power. The remaining part is regenerated as electric power by the electric motor MG1. The power distribution ratio is determined based on the gear ratio of the planetary gear 120, and constant power corresponding to the vehicle speed is regenerated as electric power by the electric motor MG1. When the torque transmitted to the axle 116 is less than the required value, the insufficient torque is output from the electric motor MG2. Electric power regenerated by the electric motor MG1 is used for driving the electric motor MG2. With this action, the hybrid vehicle can travel by converting the power output from the engine into power having the torque and the rotational speed required for the axle 116. In addition, the hybrid vehicle can travel with the engine stopped using the power of the electric motor MG2.
[0005]
Further, such a hybrid vehicle can be started by driving the electric motor MG1 and motoring the engine regardless of whether the vehicle is stopped or traveling. In the hybrid vehicle having the above-described configuration, when torque for motoring the engine is output from the electric motor MG1, a part of the torque is transmitted to the drive shaft 112 through the planetary gear. The electric motor MG2 is controlled to cancel the reaction torque transmitted from the electric motor MG1 to the drive shaft 112 and output the required torque.
[0006]
[Problems to be solved by the invention]
However, in the conventional hybrid vehicle, the torque output to the drive shaft 112 cannot be controlled with sufficient accuracy. For this reason, vibration may occur in the vehicle, and the ride comfort may be impaired, or the response of the vehicle may be impaired. Such a phenomenon is particularly remarkable in a transition period in which the rotational state of the engine and the electric motor changes greatly, such as when the engine is started. Further, in the hybrid vehicle, the influence of inappropriate torque output is particularly significant due to the following causes.
[0007]
A normal vehicle that uses only an engine as a power source includes a torque converter and a clutch that use fluid, and therefore, it is possible to suppress or avoid transmission of fluctuations in the rotational state of the engine to the axle. In a parallel hybrid vehicle, it is often unnecessary to provide a clutch or a torque converter because the power of the engine can be converted into power having a desired rotational speed and torque by an action using an electric motor. A power source composed of an engine and an electric motor is mechanically coupled to the axle, and fluctuations in the rotational state of the engine and the electric motor are directly transmitted to the drive shaft.
[0008]
Further, as described above, the hybrid vehicle can travel even when the engine is operated or stopped. Therefore, unlike a normal vehicle, the engine is frequently started and stopped according to the driving state of the vehicle even after the driving is started.
[0009]
For these reasons, in the hybrid vehicle, the influence on the ride comfort and responsiveness due to the fluctuation of the output torque to the drive shaft cannot be overlooked. The present invention has been made to solve such a problem, and an object of the present invention is to provide a technique for accurately controlling torque output to a drive shaft in a so-called parallel hybrid vehicle. In particular, there is provided a technique for outputting an appropriate torque to the drive shaft by offsetting the reaction force of the torque required for engine motoring at the start and stop of the engine that greatly affects the torque fluctuation output to the drive shaft. For the purpose.
[0010]
[Means for solving the problems and their functions and effects]
In order to solve at least a part of the above problems, the present invention employs the following configuration.
The hybrid vehicle of the present invention
An engine, a power adjusting device coupled to the output shaft and the drive shaft of the engine and capable of adjusting the magnitude of power output to the two rotating shafts by exchanging electric power, and an electric motor coupled to the drive shaft A torque sensor for detecting rotational torque at at least one location on a transmission path for transmitting power from the engine to the drive shaft;
Rotation state setting means for setting a target rotation state of the drive shaft;
Engine control means for controlling the operation of the engine in accordance with the driving state of the vehicle and the target rotational state;
Power adjustment device control means for controlling the power adjustment device in accordance with the operating state and target rotation state of the engine;
Output torque specifying means for specifying torque output to the drive shaft based on a detection result by the torque sensor;
The gist of the invention is to provide a motor control means for controlling the operation of the motor by compensating for the deviation between the specified torque and the torque corresponding to the target rotational state.
[0011]
According to such a hybrid vehicle, the operation of the electric motor can be controlled based on the torque measured by the torque sensor. The torque sensor can detect fluctuations in rotational torque on the transmission path with a slight time delay. Therefore, according to the hybrid vehicle, the torque output to the drive shaft can be appropriately controlled without time delay or vibration, and the riding comfort of the hybrid vehicle can be improved or the responsiveness can be improved. it can.
[0012]
Various known torque sensors can be applied to the torque sensor itself provided in the hybrid vehicle of the present invention. In the case of a hybrid vehicle, since the rotating shaft constituting the power transmission path rotates at high speed, a so-called non-contact torque sensor is preferable. In particular, a sensor using a change in magnetic permeability that occurs when torque is applied to the rotating shaft is preferable from the viewpoint of accuracy and responsiveness.
[0013]
In a conventional vehicle using only an engine as a power source, there has been no concept of controlling the torque output from the drive shaft. That is, the engine is usually controlled to output power according to the accelerator opening, and as a result, a predetermined torque is output according to the rotational speed of the drive shaft. Therefore, in the conventional vehicle, there is no need to provide a torque sensor on the power transmission path from the engine to the drive shaft.
[0014]
On the other hand, the hybrid vehicle includes an electric motor as a power source in addition to the engine. The operation of the electric motor is performed based on the target rotation speed and the target torque. Therefore, in the hybrid vehicle, it is necessary to set the target rotational state of the drive shaft, that is, the target rotational speed and the target torque. A major feature of the hybrid vehicle is that the torque on the power transmission path becomes a parameter necessary for control in this way.
[0015]
On the other hand, in the case of a hybrid vehicle, the torque on the transmission path can be obtained by calculation. Conventionally, from the viewpoint of reducing the manufacturing cost and improving the reliability of a hybrid vehicle, the torque on the transmission path is specified by calculation, and the target torque of the electric motor is set. No problems or limitations with this method were pointed out. As shown below, the inventor has identified problems and limitations when specifying torque on the transmission path by calculation, and in order to solve such problems, the torque on the transmission path is detected in real time by a torque sensor. I found that doing was the best way.
[0016]
Here, taking the hybrid vehicle having the configuration shown in FIG. 1 as an example, a method for identifying torque on the transmission path by calculation and its problems will be described. In the configuration shown in FIG. 1, planetary gear 120 and electric motor MG1 correspond to the power adjustment device of the present invention, and electric motor MG2 corresponds to the electric motor of the present invention.
[0017]
In the hybrid vehicle, the target torque of electric motor MG2 is set based on the difference between the required torque to be output from drive shaft 112 and the torque transmitted from electric motor MG1 and the engine to drive shaft 112. The torque to be output from the drive shaft 112 is set by multiplying the traveling torque to be output from the axle 116 by a coefficient corresponding to the gear ratio of the differential gear 114. The torque output from the motor MG1 and the engine to the drive shaft 112 can be calculated as follows based on the mechanical properties of the planetary gear 120 according to the rotation state of the motor MG1 and the engine.
[0018]
FIG. 2 is a schematic diagram of the planetary gear 120. When planetary gear 120 determines the number of rotations and torque of two rotation shafts among the three rotation shafts coupled to sun gear 121, ring gear 122, and planetary carrier 124 (hereinafter collectively referred to as the rotation state). It has a well-known property that the rotational state of the remaining rotating shaft is determined. It is known that the following equation (1) holds for the number of rotations of each rotating shaft.
[0019]
Nr = (1 + ρ) Nc−ρNs;
Nc = (Nr + ρNs) / (1 + ρ);
Ns = (Nc−Nr) / ρ + Nc; (1)
Here, Ns is the rotational speed of the sun gear shaft 125, Nr is the rotational speed of the ring gear shaft 126, and Nc is the rotational speed of the planetary carrier shaft. Further, ρ is a gear ratio between the sun gear 121 and the ring gear 122 as represented by the following equation.
ρ = number of teeth of sun gear 121 / number of teeth of ring gear 122
[0020]
On the other hand, the torque relationship is derived from the following equation of motion. First, variables are defined as shown in FIG. That is, the inertia ratio is represented by I, the angular acceleration is represented by β, the torque is represented by T, and the radius is represented by R. The sun gear 121 is “s”, the planetary carrier 124 is “c”, and the ring gear 122 is “r”. It shall be attached. Further, a reaction force acting between the ring gear 122 and the planetary pinion gear 123 is Fr, and a reaction force acting between the planetary pinion gear 123 and the sun gear 121 is Fs. Each inertia ratio means a value including not only the inertia ratio of the gear but also the inertia ratios of the motors MG1 and MG2 and the engine 150 coupled thereto.
[0021]
At this time, the equation of motion of each gear is expressed by the following equation (2).
Is · βs = Ts−3Rs · Fs;
Ic · βc = Tc + 3Rs · Fs−3Rr · Fr;
Ir · βr = Tr + 3Rr · Fr; (2)
[0022]
Here, it is considered that the planetary pinion gear 123 has an inertia ratio of approximately zero. At this time, since the moment acting on the planetary pinion gear 123 should be 0, Fs = −Fr. Further, the relationship between the previously used gear ratio ρ and radius is ρ = Rs / Rr. Further, Ta = 3 (Rs · Fs−Rr · Fr). This means torque acting on the sun gear 121 and the ring gear 122 from the planetary carrier 124 by the reaction forces Fs and Fr acting between the gears. Substituting these quantities into the above equation (2), the following equations (3) to (5) can be obtained.
[0023]
Is · βs = Ts−ρ · Ta / (1 + ρ) (3)
Ic · βc = Tc−Ta (4)
Ir · βr = Tr + Ta / (1 + ρ) (5)
Further, the relationship of the following equation (6) is established between the angular accelerations βs, βc, and βr from the equation (1) shown above.
βc = (βr + ρβs) / (1 + ρ) (6)
[0024]
Equations (3) to (6) are equations that give the rotation state of the planetary gear 120. Equation (1) may be used instead of equation (6). In these four equations, there are seven variables: βs, βc, βr, Ts, Tc, Tr and Ta. Therefore, if three independent variables among these seven variables are specified, the rotation state of the planetary gear 120 is uniquely defined.
[0025]
Here, in the transition period in which the engine and the electric motor MG1 change greatly, such as when the engine is started, the influence of the change rate appears very large as is apparent from the above equation. In such a transition period, a part of the torque output from the engine and the electric motor MG1 is consumed to change the rotational speed of the system including the engine and the electric motor MG1, and a kind of torque loss occurs. If the above equation is used, it is possible to obtain the torque output to the drive shaft 112 in consideration of such torque loss.
[0026]
For the above calculation, it is necessary to detect the rotational speeds of the electric motor MG1 and the engine. However, it has been difficult to accurately detect the rotational speeds of the electric motor MG1 and the engine. For example, if both rotation speeds are detected in a state including a time delay, the calculation result of the above equation includes an error corresponding to the delay. Of course, the rotation speed detection error itself is also included. In addition, since there is a possibility that the electric motor MG1 rotates in both positive and negative directions, it may not be possible to specify whether the rotation is in the positive or negative direction when the rotational speed is relatively low. Due to these various causes, the calculation using the above equation cannot determine the torque output to the drive shaft with sufficient accuracy during the transition period. Moreover, since the above equation has a large amount of calculation, there has been a problem that it is difficult to perform control sufficiently following actual torque fluctuation.
[0027]
In order to avoid these factors sufficiently and obtain the output torque with high accuracy, it is required to increase the number of sensors and increase the speed of the arithmetic circuit. As a result of detailed examination and experiment, the present inventor has found that when the output torque is calculated with sufficient accuracy using the above equation, the control device has a very complicated and expensive configuration. The present invention is the easiest and best way to control the operation of the electric motor MG2 by using the torque sensor, which seems to lead to an increase in cost and a decrease in reliability, at the same time reflecting the influence of torque loss. It was made based on the knowledge that there is.
[0028]
The above description has been made by taking the hybrid vehicle having the configuration of FIG. 1 as an example. The influence of the inertia of the engine or the like similarly occurs in any configuration of the hybrid vehicle. The difficulty of obtaining the output torque by calculation is the same in hybrid vehicles having other configurations.
[0029]
According to the hybrid vehicle of the present invention, as described above, the torque sensor can detect the torque of the power transmission path sufficiently following the fluctuation. The detected torque is a value including the influence of torque loss due to inertia. The value detected by the torque sensor naturally includes an error, but the influence on the control is very small as compared with a conventional calculation error. Since the torque that already includes the influence of inertia is detected, it is possible to set the target torque of the motor by a very simple calculation. With these actions, according to the hybrid vehicle of the present invention, the torque output to the drive shaft can be appropriately controlled. Therefore, vibrations and the like of the hybrid vehicle can be suppressed, and riding comfort and responsiveness can be improved.
[0030]
In the hybrid vehicle of the present invention,
The engine control means is means for starting or stopping the engine when the driving state of the vehicle and the target rotation state are in a predetermined state,
The power adjustment device control means is means for operating the power adjustment device to output a motoring torque for starting or stopping the engine,
The output torque specifying means is preferably means for specifying reaction force torque output to the drive shaft when the power adjusting device outputs the motoring torque.
[0031]
In such a hybrid vehicle, motoring torque is output from the power adjustment device to start and stop the engine. Torque is output in the direction that increases the engine speed at start-up, and reverse torque is output at stop. As described above, when the engine is started and stopped, the rotational speed of the engine and the like greatly fluctuates. Therefore, a fluctuation in the torque output to the drive shaft appears as a reaction torque. Such fluctuations are very easy to be detected by the passengers of the hybrid vehicle, so that the ride comfort of the vehicle is greatly impaired. According to the hybrid vehicle having the above configuration, the operation of the electric motor can be controlled to appropriately cancel the reaction torque when the engine is started and stopped. Therefore, the riding comfort of the hybrid vehicle can be greatly improved.
[0032]
In addition, in the case of application when starting and stopping the engine,
A stopping state determining means for determining whether or not the vehicle is stopped;
The rotational state setting means is means for setting the torque and the rotational speed of the drive shaft to a value of 0 as the target rotational state when it is determined that the vehicle is stopped.
When it is determined that the vehicle is stopped, a stop control unit that executes control using the output torque specifying unit and the electric motor control unit may be provided.
[0033]
It is necessary to keep the torque output to the axle constant while the vehicle is stopped. If the vehicle is stopped on a flat place, the torque is kept constant at a value of 0. On an uphill or the like, the torque is kept constant at a positive value corresponding to the gradient. In either case, the vehicle vibrates if the torque output to the axle fluctuates. In general, when the vehicle is stopped, the occupant is very sensitive to vehicle vibration. Since the hybrid vehicle of the present invention can suppress a torque shock generated in the vehicle when the engine is started and stopped, the hybrid vehicle is particularly effective when the vehicle is stopped.
[0034]
Note that whether or not the vehicle is stopped can be determined by determining whether or not the shift position is at a position such as a parking range that is used only when the vehicle is stopped. Further, the determination unit may specify whether or not the vehicle is stopped based on the vehicle speed.
[0035]
In the hybrid vehicle of the present invention, various configurations can be applied to the power adjustment device, and in particular, a generator and a planetary gear in which three rotating shafts are respectively coupled to the generator, the engine, and the drive shaft. It is preferable that it is an apparatus provided. For example, the configuration shown in FIG. The electric motor MG1 in FIG. 1 corresponds to a generator. However, each shaft of the planetary gear and the engine, generator, and motor can be combined in various combinations. In the hybrid vehicle having such a configuration, the influence of the inertia on the output torque is likely to appear, so that the present invention can be applied particularly effectively.
[0036]
However, the power adjustment device is not limited to the above-described configuration. Various other configurations can be applied. For example, a configuration using a counter-rotor motor may be used. The counter-rotor motor refers to an electric motor including an inner rotor and an outer rotor that are relatively rotatable around the same axis. Such an electric motor can adjust the magnitude of power transmitted from one rotor to the other rotor by controlling energization to the coil and adjusting the magnetic coupling between the two.
[0037]
In the hybrid vehicle of the present invention, torque can be detected at various sites.
As the first part,
The torque sensor may be provided at a position where the torque transmitted from the engine and the power adjustment device to the electric motor can be specified in the transmission path.
[0038]
If the engine side is called the upstream side and the drive shaft side is called the downstream side in the transmission path until the power output from the engine is transmitted to the drive shaft, the above configuration detects the torque on the upstream side of the motor. Is equivalent to The specific part can be set in various ways, and the torque transmitted to the electric motor may be directly detected. The torque of the output shaft of the engine may be detected. When the power adjustment device is configured by a combination of a planetary gear and a generator, the torque output from the generator may be detected.
[0039]
If the torque is detected at such a part, it is possible to easily obtain the torque to be output by the electric motor in order to output the torque corresponding to the target rotation state. If the operation of the electric motor is controlled based on such torque, the output torque from the drive shaft can be appropriately controlled. In addition, according to the said structure, since control of what is called an open loop can be applied as control of an electric motor, control is comparatively easy and there also exists an advantage that a high-speed process is possible.
[0040]
As the second part,
The torque sensor may be provided at a position where the torque output from the engine, the power adjustment device, and the electric motor to the drive shaft can be specified in the transmission path.
[0041]
The above configuration is the same as that for detecting torque on the downstream side of the electric motor. According to such a configuration, the torque output to the drive shaft can be directly detected, and the torque output to the drive shaft can be controlled more appropriately.
[0042]
When using a torque sensor on the downstream side of the motor,
The motor control means is preferably means for feedback-controlling the operation of the electric motor based on a deviation between the torque detected by the torque sensor and the torque corresponding to the target rotation state.
In this way, the torque output from the drive shaft can be more appropriately matched with the target torque. The feedback control can be performed in various modes such as proportional-integral control based on the deviation.
[0043]
In addition to being configured as a hybrid vehicle, the present invention can also be configured as a method for controlling the hybrid vehicle.
The control method of the present invention includes:
An engine, a power adjusting device coupled to the output shaft and the drive shaft of the engine and capable of adjusting the magnitude of power output to the two rotating shafts by exchanging electric power, and an electric motor coupled to the drive shaft A control method for controlling the operation of a hybrid vehicle comprising:
(A) setting a target rotational state of the drive shaft;
(B) controlling the power adjustment device to output a motoring torque for starting or stopping the engine;
(C) specifying a torque transmitted to the electric motor as a reaction torque of the motoring torque using a torque sensor;
(D) setting a torque that compensates for a deviation between the specified torque and a torque according to the target rotation state as the target torque of the electric motor;
(E) controlling the operation of the electric motor so as to output the specified torque.
[0044]
Also,
An engine, a power adjusting device coupled to the output shaft and the drive shaft of the engine and capable of adjusting the magnitude of power output to the two rotating shafts by exchanging electric power, and an electric motor coupled to the drive shaft A control method for controlling the operation of a hybrid vehicle comprising:
(A) setting a target rotational state of the drive shaft;
(B) controlling the power adjustment device to output a motoring torque for starting or stopping the engine;
(C) specifying a torque transmitted to the drive shaft by the power adjustment device and the electric motor using a torque sensor;
(D) It is good also as a control method provided with the process of feedback-controlling the said electric motor based on the deviation of the specified torque and the torque according to the said target rotation state.
[0045]
According to these control methods, it is possible to appropriately control the torque output to the drive shaft by the same action as described above for the hybrid vehicle, and to improve the riding comfort and responsiveness of the vehicle. it can. Of course, it is needless to say that various additional elements described above for the hybrid vehicle can also be applied to these control methods. In the above-described example, the control method for starting and stopping the engine has been described. However, the present invention is not limited to this and can be applied to other operating states.
[0046]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described based on examples.
(1) Configuration of the embodiment:
A configuration of a hybrid vehicle as an embodiment of the present invention will be described. FIG. 1 is an explanatory diagram showing the configuration of a power system that outputs the power of the hybrid vehicle. The engine 150 provided in the power system is a normal gasoline engine, and rotates the crankshaft 156. The operation of engine 150 is controlled by EFIECU 170. The EFIECU 170 is a one-chip microcomputer having a CPU, a ROM, a RAM, and the like inside. The CPU executes a fuel injection amount and other controls of the engine 150 in accordance with a program recorded in the ROM.
[0047]
The power system is further provided with motors MG1 and MG2. Motors MG1 and MG2 are synchronous motors, and include rotors 132 and 142 having a plurality of permanent magnets on the outer peripheral surface, and stators 133 and 143 wound with three-phase coils that form a rotating magnetic field. The stators 133 and 143 are fixed to the case 119. Three-phase coils wound around stators 133 and 143 of motors MG1 and MG2 are connected to battery 194 via drive circuits 191 and 192, respectively. The drive circuits 191 and 192 are transistor inverters each including two transistors as a switching element for each phase. The drive circuits 191 and 192 are connected to the control unit 190. When the transistors of drive circuits 191 and 192 are switched by a control signal from control unit 190, a current flows between battery 194 and motors MG1 and MG2. The motors MG1 and MG2 can operate as electric motors that are rotated by receiving power supplied from the battery 194 (hereinafter, this running state is referred to as power running), and the rotors 132 and 142 are rotated by external force. Can function as a generator that generates electromotive force at both ends of the three-phase coil to charge the battery 194 (hereinafter, this running state is referred to as regeneration).
[0048]
Engine 150 and motors MG1 and MG2 are mechanically coupled via planetary gear 120, respectively. The planetary gear 120 includes a planetary carrier 124 having a sun gear 121, a ring gear 122, and a planetary pinion gear 123. In the hybrid vehicle of this embodiment, the crankshaft 156 of the engine 150 is coupled to the planetary carrier 124 via the damper 130. The damper 130 is provided to absorb torsional vibration generated in the crankshaft 156. The rotor 132 of the motor MG1 is coupled to the sun gear 121. The rotor 142 of the motor MG2 is coupled to the ring gear shaft 118. The power of ring gear shaft 118 and motor MG2 is transmitted to drive shaft 112 and is transmitted to axle 116 and the wheels via differential gear 114.
[0049]
The entire operation of the hybrid vehicle of the embodiment is controlled by the control unit 190. The control unit 190 is a one-chip microcomputer having a CPU, a ROM, a RAM, and the like in the same manner as the EFIECU 170. The control unit 190 is connected to the EFIECU 170, and both can transmit various information. The control unit 190 can indirectly control the operation of the engine 150 by transmitting information such as a torque command value and a rotation speed command value necessary for controlling the engine 150 to the EFIECU 170. Further, by controlling the switching of the drive circuits 191 and 192, the operation of the motors MG1 and MG2 can be directly controlled. The control unit 190 thus controls the operation of the entire hybrid vehicle. In order to realize such control, the control unit 190 includes various sensors such as an accelerator pedal position sensor 165 for detecting the amount of accelerator depression by the driver, a shift position sensor 166 for detecting the position of the shift lever, a motor. A torque sensor 167 for detecting torque output from the MG 1 to the sun gear 121, a vehicle speed sensor 144, a sensor for detecting the remaining capacity of the battery 194, and the like are provided.
[0050]
The operation of the planetary gear 120 is as described above. When two rotation states of the sun gear 121, the ring gear 122, and the planetary carrier 124 are determined, the rotation states of the remaining rotation shafts are determined. The number of rotations of each rotating shaft is expressed by the equation (1) shown above.
[0051]
About torque, it represents with Formula (3)-(6) shown previously. However, when the inertia of each gear is ignored, the following equation (7) is established for the magnitudes of the sun gear torque Ts, the ring gear torque Tr, and the planetary carrier torque Tc. In the present embodiment, the hybrid vehicle is controlled using Expression (1) and Expression (7).
Ts = ρ · Tc / (1 + ρ)
Tr = Tc / (1 + ρ) (7)
[0052]
The hybrid vehicle of this embodiment can travel in various states based on the action of the planetary gear 120. For example, in a relatively low speed state where the hybrid vehicle has started to travel, the motor MG2 is powered while the engine 150 is stopped to travel by transmitting power to the axle 116. Similarly, the engine 150 may travel while idling.
[0053]
When the hybrid vehicle reaches a predetermined speed, the control unit 190 starts the motor 150 by motoring the engine MG1 with the torque output by powering the motor MG1. At this time, the reaction torque of the motor MG1 is also output to the ring gear 122 via the planetary gear 120. The control unit 190 controls the operation of the motor MG2 so as to output the required power from the axle 116 while canceling out the reaction torque.
[0054]
In a state where the engine 150 is in operation, the power is converted into rotational states of various rotational speeds and torques and output from the axle 116 to travel. When the engine 150 is operated to rotate the planetary carrier shaft, the sun gear 121 and the ring gear 122 rotate under conditions that satisfy the above expressions (1) and (7). The power transmitted to the ring gear shaft 118 side is transmitted to the wheels. The power generated by the rotation of the sun gear 121 is regenerated as electric power by the motor MG1. On the other hand, if the motor MG2 is powered, power can be output to the axle 116 via the drive shaft 112. When the torque transmitted from the engine 150 to the ring gear shaft 118 is insufficient, the torque is assisted by powering the motor MG2. As power for powering the motor MG2, power regenerated by the motor MG1 and power stored in the battery 194 are used. Control unit 190 controls the operation of motors MG1 and MG2 in accordance with the required power to be output from axle 116.
[0055]
The planetary gear 120 can rotate the planetary carrier 124 and the sun gear 121 while the ring gear 122 is stopped. Therefore, the engine 150 can be operated even when the vehicle is stopped. For example, when the remaining capacity of the battery 194 decreases, the battery 194 can be charged by operating the engine 150 and regenerating the motor MG1. If the motor MG1 is powered while the vehicle is stopped, the engine 150 can be motored by the torque and started. At this time, the control unit 190 controls the motor MG2 to cancel the reaction torque of the motor MG1.
[0056]
(2) Torque control processing:
Next, the torque control process in a present Example is demonstrated. The torque control process refers to a process of controlling the engine 150 and the motors MG1 and MG2 to output the power having the required torque and rotation speed from the drive shaft 112. FIG. 3 is a flowchart of the torque control process. This routine is repeatedly executed by a CPU (hereinafter simply referred to as a CPU) in the control unit 190 at predetermined intervals by a timer interrupt.
[0057]
When the torque control routine is started, the CPU first executes a running state determination process (step S10). As described above, the hybrid vehicle of the present embodiment can travel by driving the engine and motors MG1, MG2 in various states. The three driving states are used according to the driving state of the hybrid vehicle. In order to properly use the CPU, the CPU determines the running state of the vehicle when the torque control routine is started.
[0058]
FIG. 4 is a flowchart of a running state determination processing routine. In this process, the CPU first inputs a shift position (step S20). The shift position can be detected by the shift position sensor 166 shown in FIG. In this embodiment, a P range used during parking, a D range used during forward travel, a B range, an R range used during reverse travel, and a neutral are prepared as shift positions. At the same time, the CPU inputs the vehicle speed, the accelerator pedal position, and the remaining battery charge Sch (step S20).
[0059]
Next, the CPU determines the traveling state of the vehicle in the following procedure. First, it is determined whether or not the shift position is in the P range (step S30). Further, it is determined whether or not the accelerator is fully closed and the vehicle speed is lower than a predetermined speed V1 (step S35). If one of these conditions is satisfied, it is determined that the vehicle is stopped (step S40). The determination result is stored by inputting a code indicating that the vehicle is stopped to a predetermined flag indicating the running state.
[0060]
The predetermined speed V1 is set in advance so as to be a slight speed at which it can be seen that the vehicle is stopped. By determining whether the vehicle is stopped using not only the shift position but also the vehicle speed, it is determined that the vehicle is stopped even when the vehicle is stepped on the brake at the shift position such as the D range or the B range. The
[0061]
Regardless of whether or not it is determined that the vehicle is stopped, the CPU next determines whether or not the remaining capacity Sch of the battery 194 is smaller than a predetermined value CH1 (step S45). If the remaining capacity Sch is smaller than the predetermined value CH1, it is determined whether or not the engine 150 is in operation (step S50). If the engine is not in operation, the battery 194 is charged. It is determined that the engine 150 is in a traveling state in which the engine 150 should be started (step S55). The predetermined value CH1 is a lower limit value of the remaining capacity that is a criterion for determining whether to start charging the battery 194.
[0062]
If the remaining capacity Sch of the battery 194 is greater than or equal to the predetermined value Ch1 in step S45, it is next determined whether or not the remaining capacity Sch is greater than the predetermined value CH2 (step S60). If the engine value is larger than the predetermined value CH2, it is next determined whether or not the engine 150 is stopped (step S65). It is determined that there is (step S70). The determination result about the running state is stored in a predetermined flag. When the CPU executes the above processing, it ends the running state determination processing routine and returns to the torque control routine.
[0063]
Actually, in the traveling state determination processing routine, various other traveling states are determined. For example, determination is also made of EV traveling that travels without operating the engine, traveling in a mode that starts the engine, and the like. These determinations are made based on various conditions such as the vehicle speed and the state of charge of the battery 194. A detailed description of the determination process is omitted.
[0064]
When the traveling state is determined, the CPU sets the target rotational speed Nd * and the target torque Td * of the drive shaft 112 (step S100). The target rotational speed Nd * and torque Td * are set according to the current vehicle speed, the amount of depression of the accelerator, and the like. Based on the target rotational speed Nd * and torque Td * set in this way, the CPU sets the required power Pe * of the engine 150 (step S110). The required power Pe * of the engine 150 varies depending on the traveling state of the vehicle. The traveling state can be detected by a code stored in the flag set in the traveling state determination process. When the vehicle is stopped or traveling in EV, the required power Pe * of the engine 150 is basically 0 regardless of the target rotational speed Nd * and torque Td * of the drive shaft 112. However, even in such a case, when it is necessary to charge the battery 194, the power required for charging is set as the required power Pe * of the engine 150.
[0065]
When the hybrid vehicle is traveling normally, the required power Pe * of the engine 150 is charged / discharged from the battery 194 and the traveling power obtained by the product of the target rotational speed Nd * of the drive shaft 112 and the torque Td *. It is obtained by the sum of the electric power and the electric power required for driving the auxiliary machine. For example, when it is necessary to discharge surplus power from the battery 194, the required power Pe * to the engine 150 can be reduced accordingly. Further, when operating an auxiliary machine such as an air conditioner, it is necessary to output extra power from the engine 150 corresponding to electric power for the auxiliary machine in addition to the traveling power.
[0066]
When the required power Pe * for the engine 150 is set in this way, the CPU sets the operating point of the engine 150, that is, the target rotational speed Ne * and the target torque Te * (step S120). The operation point of the engine 150 is basically set by selecting from the map an operation point that provides the best operation efficiency.
[0067]
FIG. 5 is an explanatory diagram showing the relationship between the operating point of the engine 150 and the operating efficiency. A curve B in the figure shows the rotation speed and torque limit values at which the engine 150 can operate. The curves indicated by α1%, α2%, etc. in FIG. 5 are isoefficiency lines at which the efficiency of the engine 150 is constant, and show that the efficiency decreases in the order of α1%, α2%. As shown in FIG. 5, the efficiency of the engine 150 is high at relatively limited operating points, and the efficiency gradually decreases at the surrounding operating points.
[0068]
In FIG. 5, the curves indicated by C1-C1, C2-C2, and C3-C3 are curves in which the power output from the engine 150 is constant, and the operating point of the engine 150 depends on the required power. Will be selected on the curve. The state where the required power is low is shown in the order of C1-C1, C2-C2, and C3-C3. For example, when the required power Pe * to the engine 150 corresponds to the power represented by the curve C1-C1, the operating point of the engine 150 is set to the A1 point where the operating efficiency is highest on the curve C1-C1. . Similarly, an operation point is selected at point A2 on the C2-C2 curve and at point A3 on the C3-C3 curve. FIG. 6 is an explanatory diagram showing the relationship between the rotational speed of the engine 150 and the operating efficiency on a curve with constant power. The curves in FIG. 6 illustrate the three curves C1, C2, and C3 in FIG. 5 for convenience of explanation, but are curves that can be drawn innumerably according to the required output. The driving point A1 can be selected innumerably. A curve drawn by connecting points with high operating efficiency of the engine 150 in this way is a curve A in FIG. 5, which is called an operation curve.
[0069]
When the required power Pe * of the engine 150 is 0, the engine 150 is stopped or in an idle running state. For example, this corresponds to a traveling state in which the hybrid vehicle travels only with the power from the motor MG2 or when the vehicle travels downhill. Whether the engine 150 is stopped or idling is set according to the necessity of warming-up of the engine 150 and the relationship between the engine speed and the rotational speed of the drive shaft 112.
[0070]
Based on the operation point of engine 150 set by the above processing, the CPU sets the target rotational speed N1 * and torque T1 * of motor MG1 (step S130). Since the target rotational speed Ne * of the engine 150, that is, the planetary carrier 124, and the target rotational speed Nd * of the drive shaft 112 are set, the target rotational speed N1 * of the sun gear 121, that is, the motor MG1, is calculated by the above equation (1). Can be set.
[0071]
Setting of target torque T1 * of motor MG1 varies depending on the traveling state of the hybrid vehicle. When the hybrid vehicle is stopped or EV traveling, the target torque T1 * of the motor MG1 is 0. When the engine 150 is started by the motor MG1, that is, when the engine 150 is motored, the target torque T1 * of the motor MG1 is subjected to open loop control until the engine 150 reaches a predetermined speed suitable for independent operation. , Is set to a predetermined value. Similarly, when the operation of the engine is stopped, the open loop control is performed and set to a predetermined value. This value is called motoring torque.
[0072]
In a state where the engine 150 is operating independently, the target torque T1 * of the motor MG1 is basically set by so-called proportional integral control. The target torque T1 * is set based on the deviation between the current rotational speed of the motor MG1 and the above-mentioned target rotational speed N1 *. When the current rotation speed is lower than the target rotation speed N1 *, the target torque T1 * is a positive torque, and when it is opposite, it is a negative torque. The gain used when setting the torque T1 * can be set by experiment.
[0073]
The CPU sets the operation point of the motor MG2, that is, the target rotational speed N2 * and the target torque T2 *, based on the operation point of the engine 150 and the operation point of the motor MG1 set by the above processing (step S200). The target rotational speed N2 * of the motor MG2 is equal to the target rotational speed Nd * of the drive shaft 112.
[0074]
The target torque T2 * is set by the MG2 target torque setting processing routine based on the target torque Td * to the axle 116 and the reaction torque from the motor MG1. FIG. 7 is a flowchart of the MG2 target torque setting processing routine. In this process, the CPU inputs the target torque Td * of the drive shaft 112 (step S202).
[0075]
The target torque of MG2 is set so that the torque step output from engine 150 and MG1 to ring gear shaft 118 is compensated and target torque Td * is output from drive shaft 112. In this embodiment, the target torque setting method is changed according to the driving state of the vehicle. In order to execute the setting method according to the driving state, the CPU sequentially determines whether or not the vehicle is stopped (step S206) and whether or not the engine 150 is instructed to start or stop (step S208). . If at least one of these conditions is not satisfied, the CPU inputs the torque command value of MG1, that is, the torque T1 * set in step S130 of the torque control process (FIG. 3) (step S210). When both the above conditions are satisfied, the CPU detects the output torque of MG1 by the torque sensor 167 (step S212).
[0076]
Next, the CPU sets the target torque T2 * of the motor MG2 by the following procedure (step S214). First, the torque step output to the ring gear shaft 118 is calculated by the following formula (8) by substituting the torque TT1 by MG1 as the sun gear torque Ts of the formula (7) shown above.
step = TT1 / ρ (8)
[0077]
When the target torque T1 * of MG1 is input in step S210, the input value is used as the torque TT1. When the output torque of MG1 is detected by the sensor in step S212, the detected value is used as the torque TT1. The target torque T2 * of the motor MG2 is set by the difference between the target torque Td * of the drive shaft 112 and the torque step, that is, “Td * −step”.
[0078]
The CPU determines whether or not the absolute value of the target torque T2 * set in this way is larger than the rated torque Tlim of the motor MG2 (step S216). If it exceeds this, the absolute value of the target torque T2 * is rated. The torque is corrected to Tlim (step S218). This completes the target torque setting process for the motor MG2, and the CPU returns to the torque control routine.
[0079]
The CPU controls the operation of the motors MG1 and MG2 and the engine 150 according to the operation points set in this way (step S210 in FIG. 3). In the motors MG1 and MG2, voltages to be applied to the three-phase coils of the respective motors are set according to the set target rotational speed and target torque. Depending on the deviation from the current applied voltage, the driving circuits 191 and 192 It is controlled by switching the transistor. Since the method of controlling the synchronous motor is well known, detailed description thereof is omitted here.
[0080]
Since control processing for operating the engine 150 at the set operation point is well known, the description thereof is omitted here. However, the EFIECU 170 actually controls the engine 150. Therefore, in the process in step S700 in the torque control routine, a process of transmitting necessary information such as an operation point of the engine 150 from the control unit 190 to the EFIECU 170 is performed. By transmitting such information, the CPU of the control unit 190 indirectly controls the operation of the engine 150. Through the above processing, the hybrid vehicle according to the present embodiment can travel by outputting appropriate power from the drive shaft 112 and thus the axle 116 in accordance with the traveling state. Further, the engine can be appropriately started or stopped according to the driving state of the vehicle.
[0081]
According to the hybrid vehicle of the present embodiment described above, it is possible to appropriately suppress torque fluctuation when starting or stopping the engine 150 while the vehicle is stopped. In the hybrid vehicle of this embodiment, when the engine 150 is started or stopped while the vehicle is stopped, the target torque of the motor MG2 is set based on the detection result of the torque sensor 167 (see steps S206 to 210 in FIG. 7). ).
[0082]
When starting and stopping engine 150, the rotational speeds of engine 150 and motor MG1 vary greatly. In such a case, torque loss occurs in the output torque of the motor MG1 due to the influence of these inertias. Therefore, the torque command value and the actually output torque are different values. When the target torque T2 * of the motor MG2 is set based on the torque command value, the reaction force torque of the motor MG1 cannot be sufficiently canceled out, and the vehicle may vibrate. On the other hand, the torque sensor 167 of the present embodiment detects an actual output torque including such torque loss. Since the target torque T2 * of the motor MG2 is set on the basis of this detected value, the hybrid vehicle of this embodiment can appropriately cancel the reaction force torque of the motor MG1, and the vehicle vibration caused by the reaction force torque Can be suppressed. As a result, the riding comfort of the vehicle can be improved. The hybrid vehicle according to the present embodiment is particularly effective in improving the ride comfort because the above-described operation can suppress the vibration while the occupant easily senses the vibration of the vehicle while the vehicle is stopped.
[0083]
In the present embodiment, the target torque of the motor MG2 can be set by a very simple arithmetic expression as shown in the above equation (8). Therefore, according to the hybrid vehicle of the present embodiment, there is an advantage that the control process is very simple. That is, there is an advantage that appropriate control can be realized and riding comfort can be improved without causing an increase in cost due to the use of a CPU capable of extremely high speed processing.
[0084]
In the above-described embodiment, the case where the control using the detected value by the torque sensor is executed only when the engine 150 is started and stopped while the vehicle is stopped. Of course, it is also possible to perform control using the detected value by the torque sensor when the engine 150 is started and stopped regardless of whether or not the vehicle is stopped. Furthermore, it is also possible to always perform control using the detection value by the torque sensor regardless of the driving state of the vehicle.
[0085]
The process of detecting torque by the torque sensor (step S212) usually takes more time than the process of inputting the torque command value T1 * of the motor MG1 (step S210). Therefore, in an operating state where the influence of inertia is relatively small, it is preferable from the viewpoint of high-speed processing to control using the torque command value T1 *. On the other hand, if the target torque T2 * of the motor MG2 is set using the detection value of the torque sensor in a normal driving state where the engine is rotating, there is an advantage that the responsiveness of the vehicle is improved. For example, when the accelerator opening is increased, there is a slight time delay in the increase in the torque actually output to the ring gear shaft 118 due to the delay in the increase in output torque from the engine 150 and the delay in the torque change of the motor MG1. It usually happens. If the motor MG2 is controlled using the detection value of the torque sensor, the motor MG2 is controlled based on the torque actually output from the engine and the motor MG1, and as a result, torque that compensates for the influence of such time delay is obtained from the motor MG2. Output becomes possible, and responsiveness can be improved. The control using the detection value by the torque sensor and the control using the torque command value of the motor MG1 can be used in various ways depending on the operating state in consideration of these characteristics.
[0086]
In this embodiment, the position where the torque sensor is provided can be variously set. FIG. 8 is an explanatory diagram showing a configuration of a hybrid vehicle as a modification. In the configuration shown in FIG. 1, a torque sensor 167 is provided on the sun gear 121. On the other hand, the configuration of the modification is different in that a torque sensor 167a is provided on the crankshaft 156 of the engine 150. Other hardware configurations are the same as those of the embodiment shown in FIG.
[0087]
The torque control process in the hybrid vehicle of the modification is the same as that in the embodiment. In the modification, the process for setting the target torque of the motor MG2 (step S214 in FIG. 7) is different from the embodiment as follows.
[0088]
When setting the target torque of the motor MG2 based on the torque command value of the motor MG1, the process is the same as step S214 in the embodiment. That is, the torque step output to the ring gear shaft 118 is calculated by the equation (8) described above, and the target torque T2 * of the motor MG2 is set. On the other hand, when using the value detected by the torque sensor, the detected value TT2 is substituted into the planetary carrier shaft torque Tc in the equation (7) shown above, and the torque step is expressed by the following equation (9). calculate.
step = TT2 / (1 + ρ) (9)
[0089]
The torque between the gears of the planetary gear 120 is maintained in a static balanced state at each moment. Therefore, the torque loss caused by the influence of inertia can be measured not only on the sun gear 121 but also on the crankshaft 156 of the engine 150. There is no difference between the two in terms of accuracy and responsiveness. Therefore, the torque output to the drive shaft 112 can be appropriately controlled by the configuration of the modification as in the embodiment. The part where the torque sensor is provided is not limited to these, and various other settings are possible. For example, the ring gear shaft 118 may be provided.
[0090]
(3) Second embodiment:
Next, a second embodiment of the present invention will be described. FIG. 9 is an explanatory diagram showing the configuration of the hybrid vehicle as the second embodiment. In the first embodiment (FIG. 1) and the modification (FIG. 8), a torque sensor is provided at a site until power is transmitted from the engine 150 to the motor MG2. In the power transmission path from the engine 150 to the drive shaft 112, if the engine 150 side is referred to as the upstream side and the drive shaft 112 side is referred to as the downstream side, the torque of the first embodiment is higher than the motor MG2. Was detected by a torque sensor. In contrast, the hybrid vehicle of the second embodiment differs from the first embodiment in that a torque sensor 167b is provided on the downstream side of the motor MG2, that is, on the drive shaft 112. Other hardware configurations are the same as those in the first embodiment.
[0091]
The torque control process of the second embodiment is the same as that of the first embodiment (FIG. 3). In the second embodiment, the process for setting the target torque of the motor MG2 (step S214 in FIG. 7) differs from the first embodiment as follows. FIG. 10 is a flowchart of the MG2 target torque setting processing routine.
[0092]
In this process, the CPU inputs the target torque Td * of the drive shaft (step S202). Further, it is determined whether or not the vehicle is stopped, and whether or not an instruction to start or stop the engine is given (steps S204 and S206). The processing so far is the same as in the first embodiment.
[0093]
If any one of the above conditions is not satisfied, the torque command value T1 * of the motor MG1 is input (step S210), and the target torque of the motor MG2 is set based on this value. The setting method is the same process as step S214 of the first embodiment. That is, the torque step output to the ring gear shaft 118 is calculated by the equation (8) described above, and the target torque T2 * of the motor MG2 is set. The target torque T2 * of the motor MG2 is set in an open loop.
[0094]
On the other hand, when both conditions of step S204 and step S206 are satisfied, that is, when the engine is started or stopped in the stopped state, the output torque of the drive shaft 112 is detected by the torque sensor 167b (step S213). Based on the detected value, the target torque T2 * of the motor MG2 is set by feedback control as follows (step S215).
[0095]
In the second embodiment, the target torque T2 * of the motor MG2 is set using proportional integral control which is a typical feedback control technique. That is, the target torque T2 * is set by the following equation (10) based on the deviation between the target torque Td * to be output to the drive shaft 112 and the torque Td detected by the torque sensor 167b.
T2 * = k1 · (Td * −Td) + k2 · Σ (Td * −Td) (10)
Here, k1 and k2 are the gains of proportional integral control, and appropriate values can be set analytically or experimentally.
[0096]
After setting the target torque T2 * of the motor MG2 according to the driving state of the hybrid vehicle in this way, as in the first embodiment, the upper limit guard is performed so that the set target torque T2 * does not exceed the rated value Tlim. Processing (steps S216 and S218) is performed, and the MG2 target torque setting processing routine is terminated. In the torque control processing routine (FIG. 3), the operation of the motor MG2 is controlled based on the target torque.
[0097]
According to the hybrid vehicle of the second embodiment, the target torque T2 * of the motor MG2 is feedback-controlled as described above, so that the torque output to the drive shaft 112 can be more appropriately controlled to the target torque Td *. it can.
[0098]
This control can be applied particularly effectively while the vehicle is stopped. While the vehicle is stopped, it is desirable that the axle 116 does not rotate even when the engine 150 is started or stopped. Here, when realizing such control by feedback control, control is performed so that the rotational speed of the drive shaft 112 becomes 0, and control is performed so that the torque of the drive shaft 112 becomes 0. A case may be considered. The rotational speed of the drive shaft 112 is a secondary physical quantity generated as a result of torque applied to the drive shaft 112. Further, in the feedback control using the rotational speed as the control amount, since the torque for suppressing the rotation is output after the drive shaft 112 is rotated, the rotation of the drive shaft 112 cannot be completely prevented. On the other hand, according to the hybrid vehicle of the second embodiment, since the feedback control is performed using the torque of the drive shaft 112 as the control amount, the control can be performed with very high responsiveness, The rotation can be suppressed extremely appropriately.
[0099]
In the second embodiment, the case where feedback control by proportional-integral control is performed is illustrated. Needless to say, the present invention is not limited to this, and various feedback controls can be applied. Similarly to the first embodiment, feedback control may be applied when the engine is started or stopped regardless of whether the vehicle is stopped or not regardless of the driving state. Furthermore, it is also possible to apply feedback control regardless of the driving state of the vehicle.
[0100]
In the above embodiment, the hybrid vehicle having the configuration using the planetary gear 120 is illustrated. The present invention is applicable not only to such a configuration but also to hybrid vehicles having various configurations. Naturally, the planetary gear 120 and the engine, the motor MG1, and the motor MG2 can be configured to be combined in various modes. In addition, other mechanisms that have the same operation as the planetary gear 120, that is, have three rotating shafts, and can output power by arbitrarily distributing power input from one rotating shaft to the remaining two rotating shafts. It can also be adopted.
[0101]
Furthermore, as shown below, a configuration in which the operations of the planetary gear 120 and the motor MG1 are realized by one mechanism is also possible. FIG. 11 is an explanatory diagram showing a configuration of a hybrid vehicle as a modification. The modified hybrid vehicle is different from the first embodiment in that a clutch motor CM is used instead of the planetary gear 120 and the motor MG1.
[0102]
The clutch motor CM is a counter-rotor motor having two rotors that can rotate relatively around the same axis, that is, an inner rotor 232 and an outer rotor 233. In this embodiment, a permanent magnet is affixed to the inner rotor 232 in the same manner as the rotor of the motor MG2, and a motor around which a coil is wound is applied to the outer rotor 233. The crankshaft 156 of the engine 150 is coupled to the inner rotor 232, and the rotor of the motor MG2 is coupled to the outer rotor 233. The outer rotor 233 is also mechanically coupled to the drive shaft 112.
[0103]
The clutch motor CM can control the magnetic coupling between the inner rotor 232 and the outer rotor 233 by controlling the energization of the coil with the drive circuit 191. The drive circuit 191 is composed of a transistor inverter as in the first embodiment. The power output from the engine can be transmitted to the drive shaft 112 by such magnetic coupling. In addition, by rotating the inner rotor 232 and the outer rotor 233 with a predetermined slip, it is possible to regenerate electric power according to the slip amount. Of course, it is also possible to receive torque from the battery 194 and output torque. That is, the clutch motor CM can exhibit the same function as the combination of the planetary gear 120 and the motor MG1 as a single unit.
[0104]
Even in the clutch motor CM, torque loss may occur between the torque command value and the actual output torque due to the influence of inertia. Therefore, if the actual torque is detected by the torque sensor, the torque output to the drive shaft 112 can be appropriately controlled. In this case, the torque sensor can be provided in various parts. For example, it may be provided on the crankshaft 156 (part A in the figure). Further, it may be provided between the clutch motor CM and the motor MG2 (part B in the figure). When these parts are provided, the target torque of the motor MG2 is set by an open loop (see element S214 in FIG. 7). In the case of the clutch motor CM, based on the principle of action and reaction, the detection result can be directly used as the torque step regardless of whether the detection is performed at the part A or the part B.
[0105]
The torque sensor may be further provided on the drive shaft 112 (part C in the figure). When provided in such a part, the target torque of the motor MG2 is set by feedback control (see FIG. 10). In any case, as in the embodiment, the torque output to the drive shaft 112 can be appropriately controlled, and the riding comfort and response of the hybrid vehicle can be improved.
[0106]
As mentioned above, although embodiment of this invention was described, this invention is not limited to such embodiment at all, Of course, in the range which does not deviate from the summary of this invention, it can implement with a various form. It is. For example, in the above embodiment, various controls are executed by software, but these may be realized by hardware.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing a configuration of a power system that outputs power of the hybrid vehicle.
FIG. 2 is a schematic diagram of a planetary gear 120. FIG.
FIG. 3 is a flowchart of torque control processing.
FIG. 4 is a flowchart of a running state determination processing routine.
FIG. 5 is an explanatory diagram showing the relationship between operating points of the engine 150 and operating efficiency.
FIG. 6 is an explanatory diagram showing the relationship between the rotational speed of an engine 150 and operating efficiency on a curve with constant power.
FIG. 7 is a flowchart of an MG2 target torque setting processing routine.
FIG. 8 is an explanatory diagram showing a configuration of a hybrid vehicle as a modified example.
FIG. 9 is an explanatory diagram showing a configuration of a hybrid vehicle as a second embodiment.
FIG. 10 is a flowchart of an MG2 target torque setting process routine.
FIG. 11 is an explanatory diagram showing a configuration of a hybrid vehicle as a modified example.
[Explanation of symbols]
112 ... Drive shaft
114 ... Differential gear
116 ... Axle
118 ... Ring gear shaft
119 ... Case
120 ... Planetary Gear
121 ... Sungear
122 ... Ring gear
123 ... Planetary pinion gear
124 ... Planetary Carrier
130 ... Damper
132, 142 ... rotor
133, 143 ... Stator
144: Vehicle speed sensor
150 ... Engine
156 ... Crankshaft
165 ... Accelerator pedal position sensor
166: Shift position sensor
167, 167a, 167b ... Torque sensor
190 ... Control unit
191 192 Drive circuit
194 ... Battery
232 ... Inner rotor
233 ... Outer rotor

Claims (10)

An engine, a power adjustment device coupled to the output shaft and the drive shaft of the engine and capable of adjusting the magnitude of power output to the two rotary shafts by exchanging electric power, and an electric motor coupled to the drive shaft A hybrid vehicle comprising:
Torque detecting means for detecting rotational torque at at least one location on a transmission path for transmitting power from the engine to the drive shaft;
Rotation state setting means for setting a target rotation state of the drive shaft;
Engine control means for controlling the operation of the engine in accordance with the driving state of the vehicle and the target rotational state;
Power adjustment device control means for controlling the power adjustment device in accordance with the operating state and target rotation state of the engine;
Output torque specifying means for specifying the torque output to the drive shaft based on one of the detection result by the torque detecting means selected according to the operating state of the engine and the torque command value for the motor ;
A hybrid vehicle comprising: electric motor control means for controlling the operation of the electric motor by compensating for the deviation between the specified torque and the torque corresponding to the target rotational state. The invention according to claim 1,
The output torque specifying means selects the detection result in a predetermined operation state set in advance as an operation state in which a deviation between the detection result and the torque command value is relatively large . In an operating state other than the operating state, select the torque command value ,
The predetermined operation state is a hybrid vehicle that is an operation state including at least one of starting the engine, stopping the engine, and an accelerator opening greater than a predetermined opening . The hybrid vehicle according to claim 1,
The engine control means is means for starting or stopping the engine when the driving state of the vehicle and the target rotation state are in a predetermined state,
The power adjustment device control means is means for operating the power adjustment device to output a motoring torque for starting or stopping the engine,
The output torque specifying means is a means for specifying a reaction force torque output to the drive shaft based on a detection result by the torque detecting means when the power adjusting device outputs the motoring torque. . A hybrid vehicle according to claim 3 ,
A stopping state determining means for determining whether or not the vehicle is stopped;
The rotational state setting means is means for setting the torque and the rotational speed of the drive shaft to a value of 0 as the target rotational state when it is determined that the vehicle is stopped.
A hybrid vehicle comprising stop control means for executing control using the output torque specifying means and the electric motor control means when it is determined that the vehicle is stopped. The hybrid vehicle according to claim 1,
The power adjustment device is a hybrid vehicle that is a device including a generator and a planetary gear in which three rotating shafts are respectively coupled to the generator, the engine, and a drive shaft. The hybrid vehicle according to claim 1,
The hybrid vehicle according to claim 1, wherein the torque detection means is provided at a position where the torque transmitted from the engine and the power adjustment device to the electric motor can be specified in the transmission path. The hybrid vehicle according to claim 1,
The hybrid vehicle according to claim 1, wherein the torque detection means is provided at a position where the torque output from the engine, the power adjustment device, and the electric motor to the drive shaft can be specified in the transmission path. The hybrid vehicle according to claim 7 ,
The electric motor control means is a hybrid vehicle which is means for feedback-controlling the operation of the electric motor based on a deviation between the torque detected by the torque detection means and the torque corresponding to the target rotation state. An engine, a power adjusting device coupled to the output shaft and the drive shaft of the engine and capable of adjusting the magnitude of power output to the two rotating shafts by exchanging electric power, and an electric motor coupled to the drive shaft A control method for controlling the operation of a hybrid vehicle comprising:
(A) setting a target rotational state of the drive shaft;
(B) controlling the power adjustment device to output a motoring torque for starting or stopping the engine;
(C) stopping the starting, the engine of the engine, and the torque reaction force torque of the motor ring torque in a preset predetermined condition comprises at least one of predetermined opening or the accelerator opening degree Specifying using a detection means, and specifying the reaction torque using a torque command value for the motor in a condition other than the predetermined condition;
(D) setting a torque that compensates for a deviation between the specified torque and a torque corresponding to the target rotation state as the target torque of the electric motor;
And (e) controlling the operation of the electric motor so as to output the specified torque. An engine, a power adjusting device coupled to the output shaft and the drive shaft of the engine and capable of adjusting the magnitude of power output to the two rotating shafts by exchanging electric power, and an electric motor coupled to the drive shaft A control method for controlling the operation of a hybrid vehicle comprising:
(A) setting a target rotational state of the drive shaft;
(B) controlling the power adjustment device to output a motoring torque for starting or stopping the engine;
(C) In the predetermined condition including at least one of starting the engine, stopping the engine, and an accelerator opening greater than a predetermined opening, the drive shaft is driven by the power adjustment device and the electric motor. Identifying the torque transmitted to the drive shaft using a torque detection means, and identifying the torque transmitted to the drive shaft using a torque command value for the electric motor under conditions other than the predetermined condition;
(D) A control method including a step of feedback-controlling the electric motor based on a deviation between the specified torque and a torque corresponding to the target rotation state.

Images