JP3454099B2 - Power output device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power output device having a prime mover and load torque applying means for electrically applying a predetermined load torque to an output shaft of the prime mover, and more specifically, to a power output device of the load torque applying means. The present invention relates to a power output device that prevents excessive temperature rise.

[0002]

2. Description of the Related Art A power output apparatus having a prime mover and load torque applying means for electrically applying a predetermined load torque to an output shaft of the prime mover includes a motor generator as the load torque applying means, and a prime mover. That uses almost all of the output from the motor to drive the motor-generator (so-called series hybrid type power output device), and distributes the output from the prime mover to drive the motor-generator and for other purposes, such as driving a vehicle. There is a device (so-called parallel hybrid type power output device) that is used later.

In the series hybrid type power output device, the output shaft of the prime mover is mechanically connected to the rotary shaft of the motor generator, and there is no mechanical connection with the drive shaft. The drive shaft is driven by a separately provided electric motor. In this power output device, electric power is generated because the motor generator is driven by the operation of the prime mover. At this time, the torque of the prime mover is equal to the power generation load generated by the generator. Since the power generation load is proportional to the electromotive force generated in the motor generator, when the output torque of the prime mover is large, the electromotive force generated in the motor generator is also large and the current flowing through the motor generator and its drive circuit is large.

The parallel hybrid type power output device includes a so-called mechanical distribution type (for example, see Japanese Patent Application No. 8-148677) and an electric distribution type (for example, Japanese Patent Application No. 7-145575) depending on a power distribution system. (See Japanese Patent Publication). These power output devices are different from the series hybrid type power output device in that they have a structure for transmitting the power of the prime mover to the drive shaft, but in each power output device, the output shaft of the prime mover is different. It is common in that a predetermined load torque is applied to the prime mover by a motor generator mechanically coupled to. Since the load torque changes according to the output torque of the prime mover, the load torque also increases as the output torque of the prime mover increases. Therefore, also in the parallel hybrid power output device, the electromotive force generated in the motor generator according to the output torque of the prime mover increases, and the current flowing through the motor generator and its drive circuit also increases.

[0005]

As described above, in both the series hybrid type power output device and the parallel hybrid type power output device, when the output torque of the prime mover is large, the current flowing through the motor generator and its drive circuit. Becomes larger and these temperatures rise. Originally
The motor generator and its drive circuit are designed with a sufficient rating in consideration of such temperature rise, and a sufficient cooling device is also prepared.

However, if the high torque output from the prime mover continues for a long period of time, or if the cooling capacity of the cooling device decreases due to a failure or the like, the temperature of the circuit may rise excessively. . Generally, the efficiency of the motor generator and its drive circuit decreases as the temperature rises. Therefore, if such a temperature rise is left unattended, the efficiency of the entire apparatus will decrease. The present invention has been made to solve the above problems, and an object of the present invention is to provide a power output device that prevents the temperature of a motor generator or the like and its drive circuit from rising excessively.

[0007]

Means for Solving the Problem and Its Actions / Effects A power output apparatus of the present invention has an output shaft, and a prime mover that operates in an operating state according to a required output, and an electric motor for the output shaft. A power output device having a load torque applying means for applying a predetermined load torque, wherein the temperature detecting means detects the temperature of the load torque applying means, and the temperature detected by the temperature detecting means is equal to or higher than a predetermined temperature. In one case, the gist is to provide a prime mover operating means for operating the prime mover in an operating state for reducing the temperature rise of the load torque applying means.

According to this power output device, the prime mover is operated in a state where a predetermined load is electrically applied by the load torque applying means. Further, when the temperature of the load torque applying means is equal to or higher than the predetermined temperature, the prime mover can be operated in an operating state for reducing the temperature rise.
Therefore, it is possible to prevent the temperature of the load torque applying means from rising abnormally.

The load applied by the load torque applying means may be directly applied to the output shaft of the prime mover, or via a transmission system that mechanically connects the load torque applying means and the prime mover. And may be indirectly given. Further, in the present specification, in the case of "applying a load torque", when the reverse torque is positively applied in a direction in which the output shaft of the prime mover is rotated in the direction opposite to the original rotation direction, and when the reverse torque is positively applied. It includes both the case where it becomes a resistance when the output shaft of the prime mover rotates, if not the case where it is added to.

In the above power output apparatus, the operating condition of the prime mover operating means is such that the output torque of the prime mover is limited to a predetermined value and the rotational speed of the prime mover is limited to the limited output torque. It is desirable to set the rotation speed higher than the current rotation speed according to the output torque.

When the temperature of the load torque applying means rises due to the high torque output from the prime mover, the torque output from the prime mover is limited to limit the load torque applying means. Can prevent the temperature rise. According to the power output device including the prime mover operating means, it is possible to limit the torque output from the prime mover and operate the prime mover at a rotational speed higher than the current rotational speed according to the limited output torque. . Since the power output from the prime mover is represented by the product of torque and rotation speed, such a power output device can prevent the temperature rise of the load torque applying means while outputting the predetermined required power. it can.

On the other hand, in the above power output device, the operating state of the prime mover operating means is such that the output torque of the prime mover is limited to a predetermined value.
Further, it is also preferable that the number of revolutions of the prime mover be a number of revolutions at which the prime mover can be operated with a predetermined operation efficiency at the limited output torque.

According to such a power output device, by limiting the torque output from the prime mover, the temperature rise of the load torque applying means can be prevented and the prime mover can be operated at a predetermined operating efficiency. Therefore, the operating efficiency of the power output device is not significantly reduced.

In the above power output device, the load torque applying means has a rotating shaft, and the rotating shaft is mechanically coupled to the output shaft of the prime mover, and the motor generator. The temperature detection means may be a means for detecting at least one of the temperature of the motor generator and the temperature of the drive circuit.

According to this structure, since the temperature of at least one of the motor generator and the drive circuit which constitute the above-mentioned electric load torque applying means can be detected,
It is possible to prevent the temperature of the electric load torque applying means from rising. That is, when the temperature of one of the motor generator and the drive circuit tends to rise, the temperature of the electrical load torque applying means can be configured with a simple configuration by detecting the temperature of the element that tends to rise. The rise can be prevented.
Also, if there is a predetermined relationship between the temperature rise of the motor generator and the drive circuit, the temperature of either one of them is detected, and the temperature of both is calculated based on this relationship to determine the electrical load torque. It is also possible to prevent the temperature rise of the applying means.

In the power output apparatus of the present invention, when the load torque applying means is the electric load torque applying means, a drive shaft different from the output shaft and the rotary shaft and an output from the drive shaft are further provided. It has means for setting a required torque and a required number of revolutions to be performed, and three shafts respectively coupled to the output shaft, the rotary shaft and the drive shaft, and input / output to any two shafts of the three shafts. When you decide the power to be
Three-axis power input / output means for determining the power input / output to / from the remaining one shaft based on the determined power, an electric motor coupled to the drive shaft, and an operating state of the prime mover, It is desirable that the means for controlling the motor generator and the electric motor be such that the required torque and the required number of revolutions are output from the drive shaft.

According to this structure, the load torque can be indirectly applied from the motor generator to the prime mover via the above-mentioned three-axis power input / output means, and the operation of the prime mover is controlled. The temperature rise of the motor generator can be prevented. In addition to the prime mover and the motor generator, the three-axis power input / output device is also coupled with an electric motor, and the required torque and the required number of revolutions are output from the drive shaft according to the operating state of the prime mover. Means for controlling the motor generator and the motor are also provided. Therefore, according to this power output device, the temperature rise of the motor generator can be prevented and the required torque and the required rotation speed can be output from the drive shaft.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described based on examples. (1) Configuration of Embodiment First, the configuration of the embodiment will be described with reference to FIGS. 1 to 3. FIG. 1 is an enlarged view centering on the drive circuit unit of the power output device of the present embodiment, FIG. 2 is an explanatory view showing a schematic configuration of a vehicle equipped with the power output device of the present embodiment, and FIG. 3 is a view of the present embodiment. It is explanatory drawing which shows schematic structure of the cooling system of a power output device.

First, referring to FIG. 2, the overall structure of a vehicle equipped with the power output apparatus of this embodiment will be described. The configuration of this hybrid vehicle is roughly: a power system that generates a driving force, a control system and a cooling system for the driving system, a power transmission system that transmits the driving force from the driving source to the driving wheels 116 and 118, a driving operation unit, and the like. It consists of In addition, the power system includes the system including the engine 150 and the motors MG1 and MG.
The control system includes an electronic control unit (hereinafter, referred to as EFIECU) 170 for mainly controlling the operation of the engine 150, and a motor MG.
1, a control unit 190 for mainly controlling the operation of MG2
And various sensor sections for detecting and inputting / outputting signals necessary for the EFIECU 170 and the control unit 190. Although the internal configurations of the EFIECU 170 and the control unit 190 are not shown, they are one-chip microcomputers each having a CPU, a ROM, a RAM, etc., and the CPU is described below according to a program recorded in the ROM. It is configured to perform the various control processes shown.

The engine 150 sucks a mixture of air sucked from the suction port 200 and gasoline injected from the fuel injection valve 151 into the combustion chamber 152, and cranks the movement of the piston 154 pushed down by the explosion of the mixture. It is converted into the rotational movement of the shaft 156. This explosion occurs when the air-fuel mixture is ignited and burned by the electric spark formed by the ignition plug 162 by the high voltage introduced from the igniter 158 through the distributor 160.
The exhaust gas generated by the combustion is discharged into the atmosphere through the exhaust port 202.

The operation of the engine 150 is performed by the EFIECU1.
It is controlled by 70. The control of the engine 150 performed by the EFIECU 170 includes ignition timing control of the spark plug 162 according to the rotation speed of the engine 150, fuel injection amount control according to the intake air amount, and the like. Engine 150
In order to enable the above control, various sensors indicating the operating state of the engine 150 are connected to the EFIECU 170. For example, a rotation speed sensor 176 and a rotation angle sensor 178 provided on the distributor 160 for detecting the rotation speed and the rotation angle of the crankshaft 156. In addition to this, the EFIECU 170 is also connected to a starter switch 179 for detecting the state ST of the ignition key, but other sensors and switches are not shown.

The motor MG1 is constructed as a synchronous motor generator and has a rotor 13 having a plurality of permanent magnets on its outer peripheral surface.
2 and a stator 133 around which a three-phase coil that forms a rotating magnetic field is wound. The stator 133 is formed by laminating thin sheets of non-oriented electrical steel sheets, and the case 119.
It is fixed to. This motor MG1 has a rotor 132
Operates as an electric motor for rotationally driving the rotor 132 by the interaction between the magnetic field generated by the permanent magnet provided in the stator 133 and the magnetic field formed by the three-phase coil provided in the stator 133. In some cases, these interactions cause the stator 1 to rotate.
It also operates as a generator that generates electromotive force at both ends of the three-phase coil provided in 33.

Like the motor MG1, the motor MG2 is also configured as a synchronous motor generator, and has a rotor 142 having a plurality of permanent magnets on its outer peripheral surface, and a stator 143 around which a three-phase coil forming a rotating magnetic field is wound. Equipped with. Motor M
The G2 stator 143 is also formed by laminating thin sheets of non-oriented electrical steel sheets, and is fixed to the case 119.
Like the motor MG1, the motor MG2 also operates as an electric motor or a generator.

Each of these motors MG1 and MG2 has a drive circuit 19 having a plurality of switching transistors built therein.
It is electrically connected to the battery 194 and the control unit 190 via the terminals 1 and 192. Control unit 190
Various other sensors and switches are electrically connected to the. The sensors and switches connected to the control unit 190 include an accelerator pedal position sensor 164a and a brake pedal position sensor 1
65a, shift position sensor 184, battery 19
There are four remaining capacity detectors 199 and the like.

In order to enable control of the operating condition of the hybrid vehicle including control of the motors MG1 and MG2, various signals from the driving operation unit and the remaining capacity of the battery 194 are input to the control unit 190, Further, various information is exchanged with the EFIECU 170 that controls the engine 150 by communication. As various signals from the driving operation unit, specifically, accelerator pedal position (accelerator pedal depression amount) AP from the accelerator pedal position sensor 164a, brake pedal position (brake pedal depression amount) from the brake pedal position sensor 165a. ) There is a shift position SP from the BP and shift position sensor 184. Also,
The remaining capacity of the battery 194 is detected by the remaining capacity detector 199. The remaining capacity detector 199 detects the remaining capacity by measuring the specific gravity of the electrolytic solution of the battery 194 or the weight of the entire battery 194, or calculates the remaining current capacity by calculating the charging / discharging current value and time. What to detect, battery 194
It is known that the remaining capacity is detected by instantaneously short-circuiting the terminals of, to flow a current, and measuring the internal resistance.

The drive force from the drive source is applied to the drive wheels 116, 11
The configuration of the power transmission system for transmitting to the 8 is as follows. A crankshaft 156 and a planetary carrier shaft 127 for transmitting power of the engine 150, and a motor M
Rotating shafts 125, 1 for transmitting the rotations of G1 and the motor MG2
26 is mechanically coupled to the power transmission gear 111 via a planetary gear 120 described later. Further, the power transmission gear 111 is coupled to the left and right drive wheels 116 and 118 via a differential gear 114.

Here, the crankshaft 156 and the planetary carrier shaft 1 are combined with the structure of the planetary gear 120.
27, rotation shaft 125 of motor MG1, rotation shaft 1 of MG2
The connection of 26 will be described. Planetary gear 120
Is composed of two coaxial gears, a sun gear 121 and a ring gear 122, and a plurality of planetary pinion gears 123 arranged between the sun gear 121 and the ring gear 122 and revolving around the outer circumference of the sun gear 121. The sun gear 121 is coupled to the rotor 132 of the motor MG1 via a hollow sun gear shaft 125 that is penetrated through the planetary carrier shaft 127 at the center thereof, and the ring gear 12
2 is coupled to the rotor 142 of the motor MG2 via the ring gear shaft 126. Further, the planetary pinion gear 123 is coupled to the planetary carrier shaft 127 via a planetary carrier 124 that rotatably supports the rotation shaft of the crankshaft 1.
It is connected to 56. As is well known in mechanics,
When the planetary gear 120 determines the power input / output to or from any two of the above-described three gears of the sun gear shaft 125, the ring gear shaft 126, and the crankshaft 156,
It has the property that the power input / output to / from the remaining one axis is determined.

A power take-out gear 128 for taking out power is provided in the ring gear 122, the ring gear 122 and the motor M.
It is attached at a position between G1 and the G1. This power take-out gear 128 is a power transmission gear 1 by a chain belt 129.
11, the power is transmitted between the power take-out gear 128 and the power transmission gear 111. Based on the above-described configuration and the property of planetary gear 120, the hybrid vehicle can run using only motor MG2 as a drive source, or can run using both engine 150 and motor MG2 as a drive source. Specifically, the hybrid vehicle stops the operation of the engine 150 and travels only by the motor MG2 when the engine power is not required during deceleration or downhill, and during initial acceleration.
During normal driving, while using the engine 150 as the main drive source,
The vehicle also travels using the power of the motor MG2. Engine 150
When traveling with both the motor MG2 and the motor MG2 as drive sources, the engine 150 can be operated at an efficient operation point in accordance with the required torque and the torque that can be generated by the motor MG2. It excels in resource saving and exhaust gas purification performance as compared to the vehicles that run.
On the other hand, since the rotation of the crankshaft 156 can be transmitted to the motor MG1 via the planetary carrier shaft 127 and the sun gear shaft 125, it is possible to travel while generating power by the motor MG1 by operating the engine 150.

Next, based on FIG. 1, the motors MG1 and MG are
A control device for driving and controlling the No. 2 will be described. As shown in FIG. 1, the motor MG1 is connected to the control unit 190 via a first drive circuit 191, and the motor MG2 is connected to the control unit 190 via a second drive circuit 192. Although not shown in FIG. 2, the motor MG1
The sun gear shaft 125, which is the rotating shaft of the motor, is provided with a resolver 139 for detecting the rotation angle thereof, and the ring gear shaft 126, which is the rotating shaft of the motor MG2, is also provided with the resolver 149. In addition to the various signals described with reference to FIG. 2, the control unit 190 includes the rotation angle θs of the sun gear shaft 125 from the resolver 139,
Rotation angle θ of the ring gear shaft 126 from the resolver 149
r, current values Iu1 and Iv1 from the two current detectors 195 and 196 provided in the first drive circuit 191, two current detectors 197 provided in the second drive circuit 192,
The current values Iu2 and Iv2 from 198, the remaining capacity from the remaining capacity detector 199 that detects the remaining capacity of the battery 194, and the like are input through the input port.

From the control unit 190, a switching element 6 provided in the first drive circuit 191 is provided.
Control signal SW1 for driving the transistors T11 to T16, and six transistors T21 to T as switching elements provided in the second drive circuit 192.
And a control signal SW2 for driving 26. The six transistors T11 to T16 in the first drive circuit 191 constitute a transistor inverter,
Two pairs of power supply lines L1 and L2 are arranged on the source side and the sink side, respectively, and the three-phase coils (UVW) of the motor MG1 are connected to the connection points. Since the power supply lines L1 and L2 are connected to the positive side and the negative side of the battery 194, respectively, the control unit 190 indicates the ratio of the on-time of the pair of transistors T11 to T16.
When the current flowing in each phase of the three-phase coil is made into a pseudo sine wave by PWM control, the rotating magnetic field is formed by the three-phase coil.

On the other hand, the six transistors T21 to T26 of the second drive circuit 192 also constitute a transistor inverter, and are respectively arranged in the same manner as the first drive circuit 191 and form a pair of transistors. The connection point is connected to each of the three-phase coils of the motor MG2. Therefore, the control unit 190 controls the on-time of the paired transistors T21 to T26 to control signal S.
When the current flowing in each phase of each coil is made into a pseudo sine wave by PWM control, the rotating magnetic field is formed by the three-phase coil.

Engine 150, motor MG1 and its drive circuit 191, motor MG2 and its drive circuit 19
Regarding the cooling system for cooling the power system consisting of 2 etc. Fig. 3
It will be described based on. In the present embodiment, a so-called water cooling system using cooling water is applied to all the cooling systems, but the cooling system of the engine 150 and the cooling systems of the motors MG1 and MG2 and their drive circuits are configured as independent ones. There is.

The cooling system of the engine 150 is the engine 1
The structure is basically the same as that used in a conventional vehicle having only 50 as a drive source. The engine 150 and the radiator 250 are connected by a hose 254, and the cooling water is circulated in the cooling water by a water pump 260. The cooling water absorbs the heat of the engine 150 with the water jacket 173 provided in the engine 150, and the radiator 2
The engine 150 is cooled by radiating heat at 50. The radiator 250 is provided with a cooling fan 252 to help dissipate the cooling water. Also, a water temperature sensor 174 provided in the water jacket 173.
Thus, the control unit 190 detects the cooling state of the engine 150 by detecting the temperature of the cooling water.

On the other hand, the cooling system of the motors MG1 and MG2 and their drive circuits 191 and 192 has the following configuration. As shown in FIG. 3, each of the motors MG1 and MG2 has a water jacket 2 that surrounds the outer periphery of the case 119.
58 and 259 are provided. Drive circuits 191, 19
Reference numeral 2 is in contact with the heat sink 256 through which the cooling water passes, via the substrate Bd on which the elements constituting the transistor inverter are attached. Water jacket 258, 259 and heat sink 2
56 are connected to a radiator 251 separate from the radiator 250 of the engine 150 by hoses 255, respectively, and cooling water is circulated therein by a water pump 261. With this configuration, the drive circuit 191,
The heat generated in 192 is absorbed by the cooling water passing through the inside of the heat sink 256, and the heat generated by the motors MG1 and MG2 is absorbed by the cooling water passing inside the water jackets 258 and 259. The cooling water radiates these heats by the radiator 251. The radiator 251 has
A cooling fan 253 is provided to help dissipate the cooling water.

The drive circuits 191 and 192 are provided with temperature sensors 191t and 192t adjacent to each other on the same substrate. Further, in the motors MG1 and MG2, temperature sensors 133t and 143t are provided in the coil portions wound around the stators 133 and 143 of the motors. The control unit 190 controls the drive circuits 191, 192 and the motor MG1, according to the temperatures detected by these temperature sensors.
It senses the cooling state of MG2.

In this embodiment, the cooling system of the engine 150, the motors MG1 and MG2, and the drive circuit 19 therefor.
Although the cooling systems 1 and 192 are configured as separate and independent systems, they may be configured as a single system by providing a radiator common to both. Also,
Instead of using the cooling water, a so-called air-cooling type cooling system may be configured by providing a cooling fan to each heat generating portion.

(2) General Operation Principle The general operation of the power output device having the above-described structure will be described. The operating principle of the power output device, particularly the principle of torque conversion, is as follows. Consider a case where the engine 150 is operated in a state of outputting the power P1 having the rotation speed Ne and the torque Te, and the power P2 having the rotation speed Nr and the torque Tr different from the rotation speed and the torque is output from the ring gear shaft 126. However, the power P1 and the power P2 have the same power (product of torque and rotation speed). FIG. 4 shows the relationship between the engine 150 and the rotation speed and torque of the ring gear shaft 126 at this time.

In general, "power" is a scalar quantity that means output energy per unit time, that is, work rate, and there can be an infinite number of combinations of torque and rotation speed for one value. For convenience of description, "power" is used herein.
In this case, it means the work rate consisting of a specific combination of torque and rotation speed. For example, the power P1 and the power P2 shown in FIG. 4 have different combinations of torque and rotational speed even if the power is the same. Therefore, in this specification, both are treated as different motive powers.

In order to understand the general operating principle of this embodiment, it is necessary to understand the operation of the planetary gear 120. According to the teaching of mechanics, the relationship between the rotational speeds and torques of the three axes of the planetary gear 120 (the sun gear shaft 125, the ring gear shaft 126, and the planetary carrier shaft 127) can be represented as a collinear chart illustrated in FIG. , Can be solved geometrically.
The relationship between the rotational speeds and torques of the three axes in the planetary gear 120 can be mathematically analyzed by calculating the energy of each axis without using the collinear chart described above. In this embodiment, an alignment chart will be used for ease of explanation.

The vertical axis in FIG. 5 is the rotational speed axis of three axes, and the horizontal axis is the ratio ρ (ρ = Zs / Zr) of the number of teeth (Zs) of the sun gear 121 to the number of teeth (Zr) of the ring gear 122.
It is a coordinate axis determined based on. In this coordinate axis,
Both ends thereof are defined as coordinates S and R of the sun gear shaft 125 and the ring gear shaft 126, and a coordinate C of the planetary carrier shaft 127 is defined as a coordinate that internally divides the coordinate S and the coordinate R into 1: ρ.

The rotation speed of each axis of the planetary gear 120 is plotted on the above-mentioned coordinate axes. As is apparent from the configuration shown in FIG. 2, since the crankshaft 156 of the engine 150 is connected to the planetary carrier shaft 127, when the engine 150 is operating at the rotational speed Ne, the rotational speed of the planetary carrier shaft 127 is increased. Also becomes Ne. Therefore, as shown in FIG. 5, the rotation number of the coordinate C can be plotted as Ne. On the other hand, since the case where the ring gear shaft 126 is operated at the rotation speed Nr is considered, the rotation speed of the coordinate R can be plotted as Nr. By drawing a straight line passing through these two points, the rotation speed Ns of the sun gear shaft 125 can be obtained as the rotation speed on this line at the coordinate S. Less than,
This straight line is called a motion collinear line. The rotation speed Ns can also be obtained by a proportional calculation formula using the rotation speed Ne and the rotation speed Nr, and Ns = ((1 + ρ) Ne−Nr) / ρ
Is expressed as As described above, in planetary gear 120, when any two rotations of sun gear 121, ring gear 122 and planetary carrier 124 are determined, the remaining one rotation is determined based on the determined two rotations.

Next, the relationship between the torques applied to the three axes will be determined using a collinear chart. According to the mechanics, the relation of torque is equal to the equilibrium relation of forces acting on the rigid body by treating the motion collinear line as a rigid body and expressing each torque by a force as a vector based on the acting direction and magnitude of the acting collinear body. Become. Specifically, the torque Te of the engine 150 is applied from the vertical bottom to the top at the coordinate C of the planetary carrier shaft 127 as shown in FIG. Since the vector representing the torque Te can be treated as a force, the torque Te applied on the coordinate axis C is the torque Tes at the coordinate S and the coordinate R at the coordinate R by the method of separating the force into different action lines having the same direction. It can be separated into torque Ter.
At this time, the magnitude of the torque Tes is Tes = Te / (1+
ρ) and the magnitude of the torque Ter is Ter = Te
-It is represented by the expression ρ / (1 + ρ). On the other hand, since the torque Tr is output from the ring gear shaft 126, the torque Tr acts on the operation collinear line at the coordinate R from vertically above to below.

In order for the operating collinear line to be stable in this state, the forces of the operating collinear line should be balanced. That is,
On the coordinate axis S, a torque Tm1 having the same magnitude and opposite direction as the torque Tes is applied, and on the coordinate axis R, a torque and torque having the same magnitude as the torque Tr output to the ring gear shaft 126 but opposite direction. A torque Tm2 having the same magnitude but opposite direction with respect to the resultant force with Ter may be applied. The torque Tm1 is generated by the motor MG1.
Can be operated by the motor MG2. At this time, the motor MG1 that applies a torque in the direction opposite to the rotation direction operates as a generator, and regenerates the electric power Pm1 represented by the product of the torque Tm1 and the rotation speed Ns from the sun gear shaft 125. The motor MG2 whose rotation direction and torque direction are the same operates as an electric motor, and the electric power Pm
While consuming 2, the power represented by the product of the torque Tm2 and the rotation speed Nr is output to the ring gear shaft 126.

In the alignment chart shown in FIG. 5, the rotation speed Ns of the sun gear shaft 125 is positive, but the rotation speed N of the engine 150 is N.
Depending on e and the rotation speed Nr of the ring gear shaft 126, the rotation speed may be negative or the rotation speed may be zero. In these cases, the motor MG1 operates as an electric motor and the torque Tm
Power Pm1 represented by the product of 1 and the number of revolutions Ns is consumed.

As described above, in the power output apparatus according to this embodiment, the power output from the engine 150 can be converted into torque and output. Therefore, when power consisting of the rotation speed Nr and the torque Tr is designated as the required output of the drive shaft 126, the engine 1 is operated under the condition that the power is constant, that is, the product of the rotation speed and the torque is constant Nr × Tr.
The 50 driving points can be freely selected. Although the efficiency of the engine 150 changes depending on the driving point,
In the present embodiment, the engine 150 can be operated while selecting the most efficient operation point under the above-described conditions, so that power can be output with high efficiency.

FIG. 6 shows how the operating point of the engine 150 is selected. A curve B in the drawing shows the limit values of the rotational speed and the torque at which the engine 150 can operate. Figure 6
The curves indicated by α1%, α2%, etc. in FIG. 2 are isoefficiency lines in which the efficiency of the engine 150 is constant, and α
It shows that the efficiency decreases in the order of 1% and α2%. As shown in FIG. 6, the engine 150 has high efficiency at a relatively limited operating point, and the efficiency gradually decreases at operating points around the engine 150.

In FIG. 6, the curves indicated by C1-C1, C2-C2, and C3-C3 are curves in which the power of the engine 150 is constant, and the operating point of the engine 150 depends on the required output. You will choose on these curves. For example, when the required rotation speed Nr and the required torque Tr are plotted on the curve C1-C1, the operating point of the engine 150 is selected to be the A1 point where the operating efficiency is highest on the curve C1-C1. Become. Similarly C
A2 point on the 2-C2 curve and A on the C3-C3 curve
Select a driving point with 3 points. FIG. 7 shows the relationship between the engine speed of the engine 150 and the operating efficiency on each curve.
Note that the curves C1-C1 and the like exemplify the three curves in FIG. 6 for convenience of explanation, but are curves that can be drawn innumerably according to the required output, such as the operating point A1 of the engine 150. Are also innumerable. A curve that draws these innumerable driving points is curve A in FIG. Therefore, in this embodiment, the engine 150 is controlled so as to operate at the operation point on the curve A in FIG. 6 selected according to the required output.

Next, heat generated in the motor MG1 and its drive circuit will be described. In the present embodiment, the motor MG1 outputs power from the drive shaft 126 while applying a predetermined torque Tm1 as a load to the engine 150, as shown in the above-described operation principle. The magnitude of this torque Tm
As described above, 1 is represented by Tm1 = Te / (1 + ρ) and is proportional to the output torque Te of the engine 150. That is, as the torque output from the engine 150 increases, the load torque applied to the engine 150 by the motor MG1 also increases.

The motor MG1 is configured as a synchronous motor, and the sun gear shaft 125 which is the rotation shaft of the motor MG1.
The torque applied to is proportional to the magnitude of the current flowing through the drive circuit 191 and the three-phase coil. This is the motor MG
The same applies when 1 acts as an electric motor and outputs torque, and when it acts as a generator and becomes a load for the rotation of the sun gear shaft 125. On the other hand, heat is generated by the current flowing through the drive circuit 191 and the three-phase coil.
At this time, if the resistance of the entire circuit including the drive circuit 191, the three-phase coil and the battery 194 is R, and the effective value of the current flowing in the circuit is I, the amount of heat generated Q is approximately Q.
= R × I2 As described above, as the output torque Te of the engine 150 increases, the motor MG
1 and its driving circuit 191 also generate a large amount of heat. The motor MG2 also generates heat according to its output torque. In the present embodiment, the cooling system shown in FIG. 3 operates the power output device while absorbing and radiating these heats.

(3) Driving Point Correction Routine In the above-mentioned "(2) General operation principle", the power output principle in the hybrid vehicle having the configuration of this embodiment has been described. Next, a driving point correction routine, which is a characteristic part of this embodiment, will be described with reference to FIG. This routine is used when the temperature of the motor generator, clutch motor and its drive circuit becomes excessive when the high torque output from the prime mover continues for a long period of time or when the cooling capacity of the cooling device decreases due to a failure etc. This is a routine for preventing the rising of the vehicle. The driving point correction routine is
When the control unit 190 controls the operation of the engine 150, the control unit 190 is periodically executed at a predetermined time after execution of a routine for setting an operation point of the engine 150 according to a required output.

When the operation point correction routine is executed, the control unit 190 reads the temperature of the motor MG1 (step S100). This temperature is detected by the temperature sensor 133t provided in the motor MG1. next,
The control unit 190 calculates the limit value (Tg) of the output torque of the engine 150 based on the temperature tg of the motor MG1 (step S105). The limit value Tg of the output torque of the engine 150 is obtained by reading from the limit map set based on the relationship with the temperature tg of the motor MG1. An example of this restriction map is shown in FIG. According to the restriction map of FIG. 9, when the temperature tg of the motor MG1 is equal to or lower than the predetermined value tg1, the engine 150 can output the maximum value Tmax. When the temperature tg of the motor MG1 is a predetermined value tg1 or more, the temperature tg
The output torque of the engine 150 is limited in accordance with the above, and the output torque is limited to the value 0 at a certain temperature.

The restriction map shown in FIG. 9 shows the motor MG1.
It can be experimentally set according to the cooling capacity of the cooling device. In FIG. 9, the torque is linearly limited at a predetermined value tg1 or more, but it may be limited to a curve or stepwise. Further, since the torque limit map largely depends on the cooling capacity, a plurality of limit maps may be selectively used depending on whether or not the cooling system is out of order. As a method of properly using a plurality of restriction maps, a method of detecting a temporal change of the temperature tg of the motor MG1 and determining that there is some failure in the cooling system when the temporal change of the temperature tg is small can be considered.

In the present embodiment, the limit map of FIG. 9 is the control unit 19 as the table data for associating the temperature tg of the motor MG1 with the torque limit value of the engine 150.
It is stored in the ROM provided in 0. If the limit map can be expressed by a mathematical expression, the motor MG1
It may be calculated as a function of the temperature tg.

Next, the control unit 190 controls the motor MG
The temperature Ti of the first driving circuit 191 is read (step S
110). This temperature is detected by the temperature sensor 191t provided in the drive circuit 191. Control unit 19
0 calculates the limit value Ti of the output torque of the engine 150 based on this temperature (step S115). The limit value Ti of the output torque of the engine 150 is determined by the drive circuit 19
It is obtained by reading from the limit map set based on the relationship with the temperature ti of 1. An example of this restriction map is shown in FIG. According to the restriction map of FIG. 10, when the temperature ti of the drive circuit 191 is equal to or lower than the predetermined value ti1, the engine 150 can output up to the maximum Tmax. When the temperature ti of the drive circuit 191 is equal to or higher than the predetermined value ti1, the output torque of the engine 150 is limited according to the temperature ti, and the output torque is limited to the value 0 at a certain temperature.

The limit map shown in FIG. 10 can be set on a trial basis like the limit map shown in FIG. 9, and the torque may be limited to a curved line. Further, a plurality of torque limit maps may be selectively used depending on whether the cooling device is out of order. Although the restriction map of FIG. 10 is stored in the ROM provided in the control unit 190 as table data, the drive circuit 1
It may be calculated as a function of the temperature ti of 91.

Next, the control unit 190 sets the minimum value of the limiting torque thus obtained as the limiting torque TL of the engine 150. That is, the limit torque Tg due to the temperature of the motor MG1 is equal to the limit torque Tg due to the temperature of the drive circuit 191.
When it is smaller than i, the limit torque TL of the engine 150 is set as the limit torque Tg due to the temperature of the motor MG1. In the opposite case, the limit torque TL of the engine 150 is set to the limit torque Ti depending on the temperature of the drive circuit 191.
And

The control unit 190 then proceeds to step S1.
25, the limit torque TL of the engine 150 thus determined is compared with the target torque required by the engine 150 (step S125). Here, the target torque refers to the torque selected on the curve A shown in FIG. 6 according to the required output, and is set by the control unit 190 in another routine before executing the operation point correction routine. Torque. When the target torque is larger than the limit torque TL, the target torque is replaced with TL (step S130). That is, the torque above the limit torque TL is prevented from being output from the engine 150.

By the above process, the output torque of the engine 150 is T which is lower than the target torque to be originally output.
Since it is replaced with L, the engine 15
0 cannot output as requested. Therefore, the control unit 190 next corrects the rotation speed of the engine 150. For the C1-C1 curve shown in FIG. 6, this changes the operating point of the engine 150 from A1 to another operating point on C1-C1 having a lower torque and a higher rotational speed, for example, A1 ′ in FIG. Corresponds to the process.

In order to perform such processing, the control unit 19
0 reads the required output (Pe) of the engine 150 (step S135). The required output is the engine 150
It means the work rate obtained by the product of the torque and the rotation speed required for. Next, the control unit 190 sends the required output P
By dividing e by the limit torque TL, the engine 15
A target rotational speed Ne of 0 is calculated (step S140).
As a result, the operating point of the engine 150 is changed to the operating point of the torque TL and the rotation speed Ne while maintaining the required output Pe.

On the other hand, in step S125, if the target torque is less than or equal to the limit torque TL, the engine 1
Since it is not necessary to change the driving point of 50, the control unit 190 temporarily ends the driving point correction routine without performing any processing.

After the operation point correction routine is completed,
The power output apparatus according to the present embodiment operates the engine 150 with the target torque and rotation speed set by the routine. This operation is performed by the control unit 190 executing a routine separately provided for controlling the operation of the engine 150. Specifically, the control unit 1
From 90, the EFIECU 170 outputs a signal instructing to drive the engine 150 at the target torque and the rotational speed. The EFIECU 170 controls the fuel injection amount and the like of the engine 150 based on this signal, and the engine 1
The 50 is operated at the target torque and the rotational speed.

When the engine 150 is operated at the target torque and the rotational speed set by the operating point correction routine, the torque conversion described above as the general operating principle drives the power having the required rotational speed and torque. It can be output from the axis 126.

By executing the operation point correction routine of this embodiment, the torque output from the engine 150 is limited to a torque lower than the originally required target torque. As described above, the torque Tm1 applied to the sun gear shaft 125 by the motor MG1 is determined by the engine 15
Proportional to zero output torque. Therefore, by executing the operation point correction routine, Tm1 is also reduced from the original torque, and the motor MG1 and the drive circuit 19 therefor.
The heat generation amount at 1 is reduced. As a result, overheating of the motor MG1 and its drive circuit 191 can be prevented. Moreover, at this time, since the engine 150 maintains the required output, the power output device can output the power including the required torque and the required rotation speed to the drive shaft 126.

As shown in FIG. 6, originally the engine 150
The operating point is set with the highest priority to the efficiency of. However, when there is a risk of overheating of the motor MG1 and its drive circuit, the operating point of the engine 150 is set with priority given to the cooling of the motor MG1 and its drive circuit, even if the operating efficiency of the engine 150 is slightly sacrificed. There is a need to. Setting such a driving point is the function of the driving point correction routine in the present embodiment.

In the above embodiment, the temperatures of the motor MG1 and its drive circuit 191 are detected, and the operating torque of the engine 150 is limited according to these temperatures, but the temperature detection portion is limited to these. do not have to. For example, the temperature of the battery 194 may be detected in addition to the motor MG1 and the like, and the output torque of the engine 150 may be limited in consideration of the temperature of the battery 194. By adopting such a configuration, the battery 1
It is possible to prevent overheating of 94. In addition, the motor MG
2 and the drive circuit 192 thereof may be detected, and the output torque of the engine 150 may be limited in consideration of the temperatures.

If one of motor MG1 and its drive circuit 191 is likely to overheat, only the temperature of the element that is likely to overheat may be detected. For example, when the temperature rise of the motor MG1 is greater than that of the drive circuit 191, that is, the torque limit TL of the engine 150 is the torque limit value T depending on the temperature of the motor MG1 in the operation point correction routine of FIG.
When determined by g, only the temperature of the motor MG1 may be detected. Also, when there is a correlation between the temperature rises of both the motor MG1 and its drive circuit 191,
The temperature of only one of the two may be detected. In this case, the other temperature can be calculated based on the above correlation. Thus, if the temperature of either the motor MG1 or the drive circuit 191 thereof can be detected, overheating of the motor MG1 and the like can be prevented with a simple configuration.

The temperature rise of motor MG1 and its drive circuit 191 largely depends on the torque applied by motor MG1. Therefore, if there is a correlation between the temperature rise and the magnitude and time of the torque applied by the motor MG1, the temperature sensor may be configured without the temperature sensor by having this correlation as table data.

In the operation point correction routine in this embodiment, the engine 150 corrects the target torque and the target engine speed so as to maintain the required output (steps S125, S140), but the required output P is not always required.
It is not necessary to maintain e. In principle, by reducing the output torque of the engine 150, the torque applied by the motor MG1 is also reduced, and the motor MG1 is reduced.
1 and its drive circuit 191 can be prevented from overheating. Therefore, in the operating point correction routine, only the output torque may be reduced without changing the rotation speed of the engine 150. However, it is desirable to set such an operation point only when the electric power stored in the battery 194 has a margin. When the driving point is set as described above, in order to output the power having the required torque and the required rotation speed from the drive shaft 126, it is necessary to drive the motor MG2 using the electric power stored in the battery 194. Because.

A driving point correction routine provided in the power output apparatus according to the second embodiment of the present invention, which is made based on such an idea, will be described with reference to FIG. The overall structure of the power output device as the second embodiment is the same as that of the first embodiment (FIG. 2). The timing at which the driving point correction routine of this embodiment is executed by the control unit 190 is also the same as in the first embodiment.

When the operation point correction routine of the second embodiment is executed, the control unit 190 causes the engine 150 to
Calculates the output torque limit value (TL) of (step S1
50). The calculation of the output torque limit value (TL) is the same as the processing from step S100 to step S120 described in FIG. Next, the control unit 190
Compares the target torque that the engine 150 should originally output with the control torque TL (step S15).
5). When the target torque is equal to or less than the limit torque TL, it is not necessary to correct the driving point of the engine 150, and therefore the control unit 190 temporarily ends the driving point correction routine without performing any processing.

When the target torque is larger than the limit torque TL, the control unit 190 sets the value of the target torque to T.
It is replaced with L (step S160) so that the engine 150 does not output torque equal to or more than the limit torque TL. Next, the control unit 190 causes the engine request output (P
The engine speed (Np) based on e) is calculated (step S165). This process is performed by step S in FIG.
This is the same processing as 135 and step S140. That is, by dividing the engine required output Pe read by the control unit 190 by the engine limit torque TL,
The engine speed (Np) is calculated.

In the next step, the control unit 190 calculates the minimum engine speed (Nmin) (S17).
0). The engine minimum speed (Nmin) is a speed calculated based on the following concept.

When the output torque of the engine 150 is limited to TL, when the engine 150 is operated at a rotational speed lower than the value Np, the engine 150 cannot maintain the required output, so that the power output device uses the battery. It will consume 194 power. At this time, the electric power consumed by the battery 194 substantially matches the difference between the required power to be output from the drive shaft 126 and the power output from the engine 150.

Conversely, when the lower limit SOC1 of the remaining capacity of the battery 194 that does not hinder traveling is satisfied, the battery 1
When there is almost no margin in the SOC of the remaining capacity 94, the rotational speed of the engine 150 needs to be the value Np. On the other hand, when the state of charge SOC of the battery 194 is larger than SOC1, the engine 150
The number of rotations can be lower than the value Np. The minimum value of the engine speed that can be taken according to this margin is the engine minimum speed (Nmin).

Based on this concept, the process for calculating the engine minimum speed will be described with reference to FIG. In the process of calculating the engine minimum speed (Nmin), the control unit 190 reads the battery remaining capacity SOC detected by the remaining capacity detector 199 (step S20).
0). There are various methods for detecting the remaining battery charge, and there are various definitions for the remaining battery charge. In this routine, the remaining battery charge SOC is treated as a physical quantity having the same unit as the power. Such a physical quantity can be defined as, for example, the maximum value of the electric power that can be extracted from the battery 194 for a predetermined time.

Next, the control unit 190 compares the detected remaining battery charge SOC with the lower limit SOC1 of the remaining battery charge of the battery 194 that does not hinder traveling (step S205). When the remaining battery charge SOC is less than or equal to SOC1, the engine 150 needs to maintain the required output for operation, and therefore the engine speed Np based on the required engine output Pe is substituted for Nmin (step S2).
25), exit from the minimum engine speed calculation process and return to the operation point correction routine.

When the remaining battery charge SOC is larger than SOC1, the difference between the two is calculated in the next step, and SO
A margin value SOC2 of SOC for C1 is calculated (step S210). Further, in the next step, the control unit 190 determines the margin value SOC from the engine required output Pe.
Subtract 2 to calculate Pmin (step S215).
Pmin means the minimum required output that the engine 150 should output. That is, when the output of the engine 150 is Pmin and the power of the battery 194 is consumed by the value SOC2, the power output device can maintain the required output Pe.

The control unit 190 uses the calculated minimum required output Pmin as the engine torque limit value TL (see FIG. 1).
The minimum engine speed Nmin is calculated by dividing the minimum engine speed Nmin (step S220).
Thus, the engine minimum speed calculation process (step S17)
0) is ended, and the operation point correction routine is returned to.

Returning to FIG. 11, the continuation of the operation point correction routine will be described. As a result of the engine minimum speed calculation process (step S170), the remaining capacity SOC of the battery 194
In consideration of the above, the rotational speed at which the engine 150 can operate is Nm.
It is required to be in the range of in to Np.

The control unit 190 calculates the number of revolutions (Necon) that maximizes the operating efficiency of the engine 150 within the range of the number of revolutions of the engine 150 (step S175) and sets Ne as the target engine number Ne.
Substitute con (step S180). Unlike the first embodiment, Necon is not always larger than the target engine speed Ne before the substitution process of step S180 is executed.

As shown in FIG. 6, the operating efficiency of the engine 150 changes depending on the output torque and the rotation speed. FIG. 13 shows how the operating efficiency changes in the operable range of the engine 150 calculated in step 165.
FIG. 13 shows that the straight line where the torque of the engine 150 is constant at TL (D1-D1 in FIG. 6) has a rotational speed of Nmin.
5 is a graph showing how the engine operating efficiency changes in the range from 1 to Np. As shown in FIG. 13, in step S175, the control unit 190 sets the rotation speed at the point B1 at which the operating efficiency of the engine 150 is highest to Ne.
ask as con.

In the example shown in FIG. 13, the result is that the engine speed Necon of the engine 150 is determined at the point on the curve A in FIG. 6, but depending on the value of the engine speed Nmin described above, It may not be. For example, in FIG. 13, the minimum operable number of revolutions is B1 such as Nmin2.
This is the case when the rotation speed is higher than the point. At this time, since the engine 150 cannot be operated at a rotational speed lower than Nmin2, the operating efficiency is highest when the engine 150 is operated at the rotational speed Nmin2.
The rotation speed Necon in step S175 becomes the rotation speed Nmin2. This operating point is not on the curve A in FIG.

According to the operation point correction routine of the second embodiment, the operation of the engine 150 is controlled so that it is operated at the point where the operation efficiency becomes highest under the condition that the output torque of the engine 150 is limited. It is possible to prevent the efficiency of the power output device from decreasing. When the output torque of the engine 150 is limited to TL, when the engine 150 is operated at a high rotation speed so as to maintain the required output, it is particularly effective when the operating efficiency of the engine 150 is significantly reduced. .

In this case, in order for the power output device to output power consisting of the required torque and the rotational speed, the battery 1
Although it is necessary to supply electric power from 94, the power output device described above determines the operating range of the engine 150 while considering the margin of the remaining capacity SOC of the battery 194.
There is no fear that the running of the vehicle will be hindered due to insufficient remaining capacity of the battery 194.

In the second embodiment, the engine 1
Instead of the process (steps S165 to S175) of calculating the number of revolutions that maximizes the efficiency within the operable range of 50,
It may be a step of only limiting the number of revolutions of the engine 150 to a predetermined value or less. With this configuration, if the operating efficiency of the engine 150 is significantly reduced by increasing the rotation speed of the engine 150 to a predetermined value or more, it is possible to prevent the operating efficiency from being reduced by a simple control method.

The hybrid vehicle to which the above embodiments are applied may have various configurations. Although FIG. 2 shows the configuration of a hybrid vehicle that transmits the driving forces of engine 150 and motor MG2 to drive wheels 116 and 118 via planetary gear 120, engine 150 and motors MG1 and MG1 are used.
Regarding G2, the connection via the planetary gear 120 is shown in FIG.
4 and various forms shown in FIG. For example, in the configuration shown in FIG. 2, the power output to the ring gear shaft 126 is taken out from between the motor MG1 and the motor MG2 via the power take-out gear 128 coupled to the ring gear 122. The ring gear shaft 126A may be extended to take out the power, as in the configuration shown as. Further, as in the configuration shown as a modified example in FIG. 15, the planetary gear 1 is arranged from the engine 150 side.
The motor 20, the motor MG2, and the motor MG1 may be arranged in this order. In this case, the sun gear shaft 125B does not have to be hollow, and the ring gear shaft 126B needs to be a hollow shaft. With this configuration, the power output to ring gear shaft 126B can be extracted from between engine 150 and motor MG2. Further, although not shown, the motor MG2 and the motor MG1 in FIG. 15 may be replaced with each other.

The above is a modification using the planetary gear 120, but as shown in FIG. 16, the planetary gear 1 is used.
A configuration without 20 may be adopted. In the configuration shown in FIG. 16, in place of motor MG1 and planetary gear 120 in FIG. 2, both rotor (inner rotor) 234 and stator (outer rotor) 232 are relatively rotatable about the same shaft center and can act as an electromagnetic coupling. The clutch motor MG3 is used. Clutch motor MG3
Outer rotor 232 is mechanically coupled to the crankshaft 156 of the engine 150, and the clutch motor MG3
Inner rotor 234 and rotor 14 of the motor MG2
2 is connected to the drive shaft 112A. The stator 143 of the motor MG2 is fixed to the case 119.

In this structure, energy is distributed by the clutch motor MG3 instead of the planetary gear 120. The inner rotor 234 and the outer rotor 23 are driven by electric energy input to and output from the clutch motor MG3.
The power of the engine 150 can be transmitted to the drive shaft 112A by controlling the relative rotation of the two. Also, the motor M
Since the G2 rotor 132 is attached to the drive shaft 112A, the motor MG2 can also be used as a drive source.
Further, the power of the engine 150 can be used to generate electric power by the motor MG3. Even in the hybrid vehicle having such a configuration, the clutch motor MG3 is controlled to apply the power generation load torque to the engine 150.
The current flows through the drive circuit 191 of the clutch motor MG3 in proportion to the operating torque of, and the amount of heat generation increases, so that the present invention can be applied.

Further, the hybrid vehicle may have a so-called series type structure as shown in FIG. For series hybrid vehicles, the engine 15
The zero output shaft is mechanically coupled to the generator G. A motor MG4 is connected to the drive wheels 116 and 118 by the power transmission gear 1
11 and the like, but the engine 150 is not.

Because of the above-described structure, in the series type hybrid vehicle, the power of the engine 150 is the drive wheel 11
It is used for driving the generator G without being transmitted to the motors 6, 118, and the vehicle is powered by the electric power of the battery 194.
Driven by moving. The power generation load is proportional to the electromotive force generated in the generator G. When the drive circuit 191 capable of controlling the power generation load of the generator G to a desired value is provided, an electromotive force is generated in the generator G in proportion to the operating torque of the engine 150, and the heat generation of the generator G occurs. Since the amount becomes large, the present invention can be effectively applied.

Although the embodiments of the present invention and the modifications thereof have been described above, the present invention is not limited to these, and various modifications can be made without departing from the spirit of the invention.

[Brief description of drawings]

FIG. 1 is an enlarged view centering on a drive circuit unit of a power output apparatus of this embodiment.

FIG. 2 is an explanatory diagram showing a schematic configuration of a vehicle equipped with the power output apparatus of the present embodiment.

FIG. 3 is an explanatory diagram showing a schematic configuration of a cooling system of the power output apparatus of this embodiment.

FIG. 4 is an explanatory diagram showing operating points at the time of torque conversion of the power output apparatus of this embodiment.

FIG. 5 is a collinear chart showing a torque relationship in each gear of the planetary gear.

FIG. 6 is a graph showing the relationship between engine torque and rotation speed and operating efficiency.

FIG. 7 is a graph showing the relationship between engine speed and operating efficiency when the engine output is constant.

FIG. 8 is a flowchart of a driving point correction routine of the first embodiment.

FIG. 9 is a graph showing a torque limit value based on a generator temperature in the first embodiment.

FIG. 10 is a graph showing a torque limit value based on an inverter temperature in the first embodiment.

FIG. 11 is a flowchart of a driving point correction routine of the second embodiment.

FIG. 12 is a flowchart of a minimum engine speed calculation process in the second embodiment.

FIG. 13 is a graph showing the relationship between engine speed and operating efficiency when the output torque of the engine is constant.

FIG. 14 is an explanatory diagram showing a first modification of the configuration of the mechanical distribution hybrid vehicle.

FIG. 15 is an explanatory diagram showing a second modification of the configuration of the mechanical distribution hybrid vehicle.

FIG. 16 is an explanatory diagram showing a schematic configuration of an electric distribution hybrid vehicle.

FIG. 17 is an explanatory diagram showing a schematic configuration of a series hybrid vehicle.

[Explanation of symbols]

111 ... Power transmission gear 112, 112A ... Drive shaft 114 ... Differential gear 116, 118 ... Drive wheels 119, 119A ... Case 120, 120A, 120B ... Planetary gear 121 ... Sun gear 122 ... Ring gear 123 ... Planetary pinion gear 124 ... Planetary carrier 125, 125A, 125B ... Sun gear shaft 126, 126A, 126B ... Ring gear shaft 127, 127A, 127B ... Planetary carrier shaft 128 ... Power take-out gear 129 ... Chain belt 132 ... rotor 133 ... Stator 133t ... Temperature sensor 139 ... Resolver 142 ... rotor 143 ... Stator 143t ... Temperature sensor 149 ... Resolver 150 ... engine 151 ... Fuel injection valve 152 ... Combustion chamber 154 ... piston 156 ... crankshaft 158 ... Igniter 160 ... Distributor 162 ... Spark plug 164 ... Accelerator pedal 164a ... Accelerator pedal position sensor 165 ... Brake pedal 165a ... Brake pedal position sensor 170 ... EFIECU 173 ... Water jacket 174 ... Water temperature sensor 176 ... Revolution sensor 178 ... Rotation angle sensor 179 ... Starter switch 182 ... shift lever 184 ... Shift position sensor 190, 190A, 190B ... Control unit 191 ... First drive circuit 191t ... Temperature sensor 192 ... Second drive circuit 192t ... Temperature sensor 194 ... Battery 195, 196, 197, 198 ... Current detector 199 ... Remaining capacity detector 200 ... Inhalation port 202 ... Exhaust port 232 ... Outer rotor 234 ... Inner rotor 238 ... Rotating transformer 250, 251 ... radiator 252, 253 ... Cooling fan 254, 255 ... Hose 256 ... Heat sink 258, 259 ... Water jacket 260, 261 ... Water pump G ... Generator MG1, MG2, MG4 ... Motor MG3 ... Clutch motor

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI F02D 29/06 F02D 29/06 D Q G05D 17/02 G05D 17/02 H02P 9/00 H02P 9/00 B 9/04 9 / 04 L (56) Reference JP 3-117400 (JP, A) JP 4-148037 (JP, A) JP 5-328526 (JP, A) JP 9-184436 (JP, A) ) JP-A-9-46965 (JP, A) JP-A-6-80048 (JP, A) JP-A-58-69403 (JP, A) JP-A-51-79813 (JP, A) JP-A-2- 238141 (JP, A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) B60K 6/02-6/04 B60L 11/00-11/18 F02D 29/00-29/06 H02P 9/00 -9/48

Claims (8)

(57) [Claims] 1. A power output device comprising a prime mover having an output shaft and operating in an operating state corresponding to a required output, and load torque applying means for electrically applying a predetermined load torque to the output shaft. The temperature detecting means for detecting the temperature of the load torque applying means, and when the temperature detected by the temperature detecting means is equal to or higher than a predetermined temperature, a predetermined value is set to reduce the temperature rise of the load torque applying means. A power output device comprising a prime mover operating means for operating the prime mover in an operating state in which the output torque is limited to the value of. 2. The power output device according to claim 1, wherein the operating state of the prime mover operating means is such that the rotational speed of the prime mover is higher than the current rotational speed according to the limited output torque. Power output device with high rotation speed. 3. The power output apparatus according to claim 1, wherein the operating state of the prime mover operating means is such that the number of revolutions of the prime mover is a predetermined operating efficiency at the limited output torque. A power output device that is the number of revolutions that can be driven. 4. The power output device according to claim 1, wherein the load torque applying unit has a rotating shaft, and the rotating shaft is mechanically coupled to an output shaft of a prime mover. Motor generator,
And a drive circuit for exchanging electrical energy with the motor generator, wherein the temperature detecting means detects at least one of the temperature of the motor generator and the temperature of the drive circuit. A power output device that is a means. 5. The power output device according to claim 4, wherein
Further, a drive shaft different from the output shaft and the rotary shaft, a unit for setting a required torque and a required rotational speed to be output from the drive shaft, and each of the output shaft, the rotary shaft, and the drive shaft are coupled to each other. When the power input / output to / from any two of the three axes is determined, the power input / output to / from the remaining one axis is determined based on the determined power. Three-axis power input / output means, an electric motor coupled to the drive shaft, and the motor / generator so that the required torque and the required number of revolutions are output from the drive shaft according to an operating state of the prime mover. And a means for controlling the electric motor. 6. The power output device according to claim 4, wherein a drive shaft for outputting power, means for setting a required torque and a required rotational speed to be output from the drive shaft, and the drive shaft And an electric motor coupled to the motor generator, the motor generator having two rotating shafts, the two rotating shafts being paired rotor electric motors respectively coupled to the output shaft and the drive shaft, and A power output device comprising means for controlling the motor generator and the motor so that the required torque and the required number of revolutions are output from the drive shaft in accordance with an operating state. 7. The power output device according to claim 1, wherein the load torque applying unit is configured to perform the load output in response to the required output.
Power output device that controls load torque. 8. An operation according to a required output having an output shaft
A prime mover that operates in a rotating state and an electrical location for the output shaft
And a load torque applying means for applying a constant load torque
A power output device for detecting temperature of the load torque applying means
And the temperature detected by the temperature detecting means is equal to or higher than a predetermined temperature.
In some cases, the temperature rise of the load torque applying means is reduced.
Output torque set according to the required output.
Operating conditions that result in output torque limited to a predetermined value
And a prime mover operating means for operating the prime mover.
Power output device.