JP2000255279A - Control device for hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the durability of a powder clutch by regulating the change gear ratio of a continuously variable transmission so that the output rotating speed is a set rotating speed or less, when the powder clutch is fastened in the operating state where the detected temperature of the powder clutch exceeds a set temperature, and thereafter quickly performing the fastening. SOLUTION: In this control, clutch temperature Tc is detected when a powder clutch is in open state (steps 301, 302). When the clutch temperature Tc is higher than an intermediate capacity use prohibiting temperature Toff, the lowest line of a continuously variable transmission is regulated in the direction of reducing the change gear ratio (steps 303, 304). Thereafter, the quick fastening of the clutch is permitted (step 305). Accordingly, the rotating speed of an engine can be easily controlled to mutually synchronize the input side rotating speed and output side rotating speed of the clutch. Thus, the fastening can be completed in a short time without requiring a sliding motion, and the durability of the powder clutch can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a hybrid vehicle having an engine and a rotating electric machine as power sources of the vehicle.

[0002]

2. Description of the Related Art An engine and a motor (a rotating electric machine serving both as an electric motor and a generator) as power sources for a vehicle.
A hybrid vehicle having both of them and running with one or both driving forces is known (for example, “Automotive Engineering” VOL.46 No.7 199 issued by Railway Japan Co., Ltd.)
(June 19, pp. 39-52).

[0003] In such a parallel type hybrid vehicle, basically, the vehicle travels only by a motor in an operation range where the load is relatively small, and when the load increases, the engine is started to secure a required driving force. The maximum driving force is exhibited by using a motor and an engine together. Also,
When the vehicle decelerates, regenerative operation is performed in which the motor operates as a generator, and the deceleration energy is used for charging the battery.

The output of an engine is generally controlled by a powder type electromagnetic clutch (hereinafter referred to as "powder clutch").
That. ) Is transmitted to the drive system of the vehicle. Conventionally, however, the control of the powder clutch mainly controls the transmission torque such as gradually engaging the clutch for the purpose of reducing the shock at the time of engagement. However, sufficient consideration was not given to control in consideration of the durability and fuel efficiency of the powder clutch.

For example, when attention is paid to durability, when a powder clutch is subjected to a half-clutch control in which the transmission torque is gradually increased or decreased under a certain high temperature state, the wear of the magnetic powder is accelerated by the sliding operation at this time. Not preferred. However, in order to switch the power source from the motor to the engine, the clutch must be engaged even at a high temperature, so that the durability of the powder clutch has been impaired. As a countermeasure for this, it is conceivable to temporarily suppress the switching of the power to the engine, but in such a case, sufficient output cannot be secured, so that the drivability is impaired.

When the powder clutch is released, that is, when no fastening force is generated electromagnetically, the magnetic powder inside the clutch housing is centrifugally generated by the centrifugal force with respect to the rotation of the input shaft connected to the engine. Since the magnetic powder rotates together with the input shaft while being dispersed in the surrounding portion, the wear of the magnetic powder does not progress so much. On the other hand, in a state where the engine and the input shaft are stopped and only the output shaft connected to the drive system is rotating (this is referred to as “inward rotation”), the magnetic powder is generated regardless of the rotation of the output shaft. Is accumulated below the clutch housing by its own weight, and is agitated with the rotation of the output shaft. Therefore, when the hybrid vehicle is running with only the motor with the engine stopped, the powder clutch may be left open even if the output speed is increased due to the increase in vehicle speed. Its durability may be greatly impaired.

The present invention has been made in view of such a problem, and an object of the present invention is to provide an optimum control of a powder clutch which can improve the durability of a powder clutch and the fuel consumption of a hybrid vehicle.

[0008]

According to a first aspect of the present invention, there is provided a drive system including a rotating electric machine that performs driving or regenerative power generation, a powder clutch that transmits engine rotation to the driving system, and a driving system subsequent to the rotating electric machine. A continuously variable transmission that changes the reduction ratio of the stepless continuously, and a control circuit that controls the powder clutch and the continuously variable transmission according to the vehicle operating state. When the temperature is detected and the powder clutch is engaged in an operating state where the detected temperature exceeds the set temperature, the speed ratio of the continuously variable transmission is controlled so that the output side rotation speed of the powder clutch is equal to or lower than the set speed. With this configuration, the powder clutch is quickly engaged.

According to a second aspect of the present invention, there is provided a drive system including a rotating electric machine for driving or regenerative power generation, a powder clutch for transmitting engine rotation to the drive system, and controlling the powder clutch according to a vehicle operating state. In a hybrid vehicle including a control circuit, when the control circuit shifts from a traveling state in which the powder clutch is engaged and the engine output is transmitted to the drive system to a traveling state in which the powder clutch is released and the rotating electric machine alone is used, The powder clutch is released when the output rotation speed of the powder clutch is equal to or less than the set rotation speed.

According to a third aspect of the present invention, there is provided a drive system including a rotating electric machine for driving or regenerative power generation, a powder clutch for transmitting engine rotation to the drive system, and controlling the powder clutch according to a vehicle operating state. In a hybrid vehicle including a control circuit, when the control circuit is in a running state with only the rotating electric machine with the engine stopped and the powder clutch released, the output rotation speed of the powder clutch is equal to or higher than a set rotation speed. When this happens, the powder clutch is engaged.

According to a fourth aspect of the present invention, there is provided a drive system including a rotating electric machine for driving or regenerative power generation, a powder clutch for transmitting engine rotation to the drive system, and controlling the powder clutch according to a vehicle operating state. In a hybrid vehicle equipped with a control circuit, the control circuit starts the engine from the powder clutch released state, synchronizes the engine speed with the powder clutch input side speed, and then engages the powder clutch. The target engagement vehicle speed of the powder clutch calculated from the required driving force and the vehicle speed, the period corresponding to the period from the start of the engine to the completion of rotation synchronization, rather than the actual vehicle speed reaching the target engagement vehicle speed. Only at an early stage was the configuration to output the engagement command to the powder clutch.

According to a fifth aspect of the present invention, there is provided a drive system including a rotating electric machine for driving or regenerative power generation, a powder clutch for transmitting engine rotation to the drive system, and controlling the powder clutch according to a vehicle operating state. In a hybrid vehicle including a control circuit, the control circuit, when decelerating with the powder clutch engaged, releases the powder clutch only when the rotating electric machine can generate a required deceleration torque, and reduces the deceleration torque. It was configured to generate.

According to a sixth aspect of the present invention, there is provided a drive system including a rotating electric machine for driving or regenerative power generation, a powder clutch for transmitting engine rotation to the drive system, and controlling the powder clutch according to a vehicle operating state. In a hybrid vehicle equipped with a control circuit, the control circuit is calculated by assuming that the vehicle travels only by the required driving force and the rotating electric machine when the powder clutch is engaged and the vehicle travels using the engine output. Determine the target release vehicle speed of the powder clutch using the predicted power value and release the powder clutch when the actual vehicle speed is equal to or lower than the target release vehicle speed and the required driving force can be achieved only by the rotating electric machine, The required driving force is output by the rotating electric machine and the engine is stopped.

[0014]

[Operation and Effect] As described above, when the powder clutch is heated to a high temperature, abrasion of the magnetic powder proceeds when a half-clutch control with a sliding operation is performed, so that the temperature decreases when the durability of the powder clutch is emphasized. It is necessary to suppress power switching from the rotating electric machine to the engine. On the other hand, according to the first aspect of the present invention, at such a high temperature, the speed ratio of the continuously variable transmission is regulated so that the output side rotational speed of the powder clutch does not increase to a certain degree or more. Therefore, the speed difference between the input and output shafts of the powder clutch is reduced to reduce the load at the time of fastening, and the rotation with the engine side (input shaft side) is easily synchronized to fasten without the need for sliding operation. Can be completed.
Therefore, the durability of the powder clutch can be improved, and power can be switched from the rotating electric machine to the engine even under high temperature conditions.

According to the second aspect of the present invention, when shifting from the running state in which the powder clutch is engaged and the engine output is transmitted to the drive system to the running state in which the powder clutch is released and only the rotating electric machine is used, the output side of the powder clutch is used. The powder clutch is released when the number of revolutions is equal to or less than the set number of revolutions. In other words, when the powder clutch is released, the engine is stopped and the engine is turned inside, the input side rotation speed of the powder clutch is always less than or equal to the set speed, thus preventing the durability of the powder clutch from being reduced due to excessive inside rotation. can do.

According to the third aspect of the present invention, when the engine is stopped, the powder clutch is released and the vehicle is running only by the rotating electric machine, and the output rotation speed of the powder clutch becomes equal to or higher than the set rotation speed, the powder clutch is rotated. Is to be concluded. For example, if the output-side rotation speed of the powder clutch is increased due to an increase in vehicle speed when traveling only by the rotating electric machine, this means an increase in the number of rotations inwardly, which is not preferable in terms of durability of the powder clutch. On the other hand, according to the present invention, since the powder clutch is engaged when the output-side rotation speed exceeds the set rotation speed, it is possible to prevent the inner rotation under a high-speed rotation state and improve the durability. Can be.

According to the fourth aspect of the present invention, when the powder clutch is disengaged, the engine is started, and when the powder clutch is engaged after synchronizing the engine speed and the powder clutch input side speed, the required driving force at this time is reduced. With respect to the target engagement vehicle speed of the powder clutch calculated from the vehicle speed, the powder is earlier than the actual vehicle speed reaches the target engagement vehicle speed by a period corresponding to a period from the engine start to the completion of rotation synchronization. An engagement command is output to the clutch. Starting the engine and shifting to the running state using the engine output is also an operation region where high output is required and the use of the engine is more efficient. Therefore, it is preferable to switch the operation from the rotating electric machine to the engine without delay in order to improve fuel efficiency. In this regard, according to the present invention, as described above, with respect to the target engagement vehicle speed of the powder clutch,
Since the engagement command is output to the powder clutch early in consideration of the delay time from the start of the engine to the completion of rotation synchronization, it is possible to switch the power source without waste and improve the running fuel efficiency of the vehicle. it can.

According to the fifth aspect of the present invention, at the time of deceleration in the powder clutch engagement state, the powder clutch is released and the deceleration torque is generated only when a required deceleration torque can be generated by the rotating electric machine. I have. At the time of deceleration when the driver does not request the driving force, generally, the engine brake using the internal friction of the engine provides sufficient deceleration performance, operates the rotating electric machine as a generator, and regenerates using a part of the deceleration energy. By doing so, the energy efficiency is increased. If the engine is disconnected during this deceleration state, the driver's sense of deceleration perceived as engine braking by the driver fluctuates greatly, which is not preferable. The present invention focuses on this point, and when decelerating from a state in which the vehicle is running using an engine, if sufficient deceleration torque can be generated by the electric power generation of the rotating electric machine from the beginning, powder is promptly used. The clutch is disengaged to obtain the required feeling of deceleration only by rotating electricity. When the required deceleration torque cannot be obtained only by the rotating electric machine, the powder clutch is not released. Therefore, it is possible to avoid occurrence of a torque step feeling due to disconnection of the engine during deceleration. Note that the time when the required deceleration torque can be generated by the rotating electric machine is, for example, when the maximum power generation load of the rotating electric machine, that is, the maximum deceleration torque is larger than a torque that can provide an appropriate deceleration feeling to the vehicle speed at the start of deceleration Or when the state of charge of the battery at that time can accept a power generation amount corresponding to the deceleration torque.

According to the sixth aspect of the present invention, when the vehicle is running using the engine output with the powder clutch engaged,
The target opening vehicle speed of the powder clutch is determined using the required driving force at that time and the predicted power value calculated assuming that the vehicle has traveled only by the rotating electric machine, and the actual vehicle speed is equal to or less than the target opening vehicle speed and the required driving force. When the state can be achieved only by the rotating electric machine, the powder clutch is released, and the required driving force is output by the rotating electric machine and the engine is stopped. According to the present invention, the target vehicle speed at which the powder clutch is released is determined from the relationship between the predicted electric power (required output) calculated assuming that the vehicle runs only by the rotating electric machine and the vehicle speed. In the operating range where the motor can be operated, the powder clutch is released and traveling by the rotating electric machine is performed. Therefore, it is possible to obtain the effect of improving fuel efficiency by switching the power source from the engine to the rotating electric machine in the operating region where the engine efficiency is poor. Further, since the target vehicle speed at which the powder clutch is released is determined based on the predicted power value, there is an effect that the hunting operation of the powder clutch when switching between the engine and the motor can be prevented.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. First, FIGS. 1 and 2 show a configuration example of a parallel-type hybrid vehicle to which the present invention can be applied. In FIG. 1, the power train of this vehicle is a motor 1,
The engine 2 includes a powder clutch (hereinafter, simply referred to as a “clutch”) 3, a motor 4 (the rotating electric machine of the present invention), a continuously variable transmission 5, a reduction gear 6, a differential 7, and driving wheels 8. . The output shaft of the motor 1, the output shaft of the engine 2, and the input shaft of the clutch 3 are connected to each other. The motor 1 and the engine 2 are connected to each other via a reduction gear (not shown) having a predetermined rotation ratio.
The output shaft of the clutch 3, the output shaft of the motor 4, and the input shaft of the continuously variable transmission 5 are connected to each other.

When the clutch 3 is engaged, the engine 2 and the motor 4
Is the propulsion source of the vehicle, and when the clutch 3 is released, only the motor 4 is the propulsion source of the vehicle. The driving force of the engine 2 or the motor 4 is controlled by a continuously variable transmission 5, a reduction gear 6, and a differential gear 7.
Is transmitted to the drive wheels 8 via the Pressure oil is supplied from the hydraulic device 9 to the continuously variable transmission 5 to clamp and lubricate the belt.

The motor 1 is mainly used for starting the engine and generating electric power, and the motor 4 is mainly used for power running and regenerative operation during deceleration of the vehicle. The motor 10 is for driving the oil pump of the hydraulic device 9. However, when the clutch 3 is engaged, the motor 1 can be used for powering and braking of the vehicle,
The motor 4 can be used for starting the engine or generating power.

The motors 1, 4, and 10 are driven by inverters 11, 12, and 13, respectively. When a DC electric motor is used for the motors 1, 4, and 10, a DC / DC converter is used instead of the inverter. The inverters 11 to 13 are connected to a high-power battery 15 via a common DC link 14, convert DC power of the high-power battery 15 into AC power, supply the AC power to the motors 1, 4, 10, and Is converted into DC power to charge the high-power battery 15. Since the inverters 11 to 13 are connected to each other via the DC link 14, the power generated by the motor during the regenerative operation can be directly supplied to the motor during the power running operation without passing through the high-power battery 15. it can.

Reference numeral 16 denotes a controller having the function of the control circuit of the present invention. The controller 16 includes a microcomputer and its peripheral parts, various actuators, and the like. , The speed ratio of the continuously variable transmission 5, the fuel injection amount / injection timing of the engine 2, the ignition timing, and the like.

As shown in FIG. 2, the controller 16 includes a key switch 20, a select lever switch 21,
Accelerator pedal sensor 22, brake switch 23, vehicle speed sensor 24, battery temperature sensor 25, battery SO
A C detection device 26, an engine speed sensor 27, and a throttle opening sensor 28 are connected. The selector lever switch 21 is provided for parking P, neutral N, and reverse R.
And P, N, depending on the set position of a select lever (not shown) for switching to any range of drive D.
One of the switches R and D is turned on.

The accelerator pedal sensor 22 detects the amount of depression of the accelerator pedal, and the brake switch 23 detects the state of depression of the brake pedal. Vehicle speed sensor 24
Detects the running speed of the vehicle, and the battery temperature sensor 25 detects the temperature of the high-power battery 15. The battery SOC detection device 26 detects an SOC (State Of Charge) that is a representative value of the actual capacity of the high-power battery 15. The engine speed sensor 27 detects the speed of the engine 2, and the throttle opening sensor 28 detects the throttle valve opening of the engine 2.

The controller 16 further includes an engine 2
Fuel injection device 30, ignition device 31, variable valve operating device 32
Are connected. The controller 16 controls the fuel injection device 30 to supply and stop the fuel to the engine 2 and adjust the fuel injection amount and the injection timing.
1 to control the ignition timing of the engine 2. Also,
The controller 16 controls the variable valve operating device 32 to adjust the operating states of the intake and exhaust valves of the engine 2. The controller 16 is supplied with power from a low-voltage auxiliary battery 33.

The above is an example of the basic configuration of a hybrid vehicle to which the present invention can be applied. In the present invention, the durability of such a hybrid vehicle is improved by appropriately controlling the engagement or disengagement of the powder clutch 3. It improves various performances such as fuel efficiency and fuel efficiency. An embodiment of the control contents of the controller 16 for this purpose will be described below with reference to FIGS.

FIG. 3 shows a slip operation usually performed by an intermediate capacitor.
During the clutch overheating should be prohibited, and flow diagram illustrating an outline of control to enable to perform the power switching from the motor 4 to the engine 2 smoothly, 4 shift characteristic change of the continuously variable transmission according to the control It is a shift characteristic diagram which shows an example.
Each control shown as a flowchart in FIG. 3 and subsequent figures is periodically and repeatedly executed as part of comprehensive control of the hybrid vehicle.

In this control, it is initially detected whether the clutch 3 is in the released state, and if it is in the released state, the clutch temperature Tc is detected next (steps 301 and 302). When the clutch temperature Tc is higher than a predetermined intermediate capacity use prohibition temperature Toff, as shown in FIG. 4, the lowest line of the continuously variable transmission 5 is moved in the direction in which the speed ratio becomes smaller, in the figure, the intermediate vehicle speed range. Is regulated so that the input side rotational speed ("primary rotational speed" in the figure) is at most about 2500 rpm (steps 303 and 304). The lowest line is originally set so as to regulate the maximum reduction ratio in accordance with the vehicle speed so that the engine does not over-rotate, but this is further regulated to a higher speed side, and then the clutch immediate engagement is permitted. (Step 305). Immediate clutch engagement is a control that promptly operates to an engagement state in which the transmission torque is maximized without using an intermediate capacity that involves slippage. By regulating the lowest line in this way, the continuously variable transmission 5
The input-side rotational speed of the clutch 3, that is, the output-side rotational speed of the clutch 3 is reduced with respect to the same vehicle speed as compared with before the re-regulation. And the output side rotational speed can be synchronized, and the engine 2 can be used without exhausting the clutch 3.
The power can be switched smoothly to On the other hand, in the determination of the clutch temperature Tc, when Tc is equal to or lower than the reference temperature Toff, the regulation of the lowest line is released and the use of the clutch intermediate capacity is permitted.
The engagement operation using the half clutch is enabled (steps 306 and 307).

FIG. 5 shows the control contents of another embodiment relating to the clutch engagement control executed in the process of increasing the vehicle speed. In this control, first, after detecting various operating states necessary for the control based on signals from sensors as shown in FIG. 2, it is determined whether or not the clutch 3 is in a connectable state (steps 501 and 502). ). The determination of whether or not the clutch can be engaged is, firstly, a determination as to whether or not the engine is in a state in which the clutch can be engaged. For example, when the engine has failed to start, when starting cranking is impossible, the engine is operated in series. For example, when it is detected that the clutch is in the discharged state, the control loop is ended without issuing a clutch engagement request (step 513). Also, the second
Is a determination of whether or not the clutch can be engaged as a control state of the drive system. For example, at this time, there is no request for engagement of the clutch 3 in the immediate engagement mode. That there is no engagement request, that the clutch 3 is currently released, that it is not in a temperature state in which the clutch 3 should be forcibly released, that there is no emergency release request of the clutch 3, that the continuously variable transmission 5 is in the forward travel range. (Drive range, low range, etc.), the following control is performed when all the conditions are satisfied, such as the fact that the engagement is not prohibited in the immediate mode, and the engagement request is not issued when all the conditions are not satisfied.

When it is determined in the above determination process that the engagement is possible, the target driving force of the vehicle is calculated based on signals from the throttle opening sensor 28, the vehicle speed sensor 24, and the like. That is, it is determined whether or not the vehicle is in a deceleration state (step 503). Here, when it is determined that the target driving force> 0, that is, the vehicle is not in the deceleration state, the target engagement vehicle speed c of the clutch 3 by the motor power is determined.
nvspP and the target engagement vehicle speed cnvspB of the clutch 3 based on the motor output limit value are calculated by the following equations, respectively (steps 504 and 505). Note that the target engagement vehicle speed of the clutch 3 is simply referred to as a target engagement vehicle speed below.

CnvspP = drive system representative value / motor 4 power running power / motor 4 representative efficiency / target drive power ... (1) cnvspB = drive system representative value / motor 4 reference power / motor 4 output limit value / target drive force ... ( 2) In the above equations (1) and (2), the driving system representative value is a vehicle specification value that affects the driving force of the motor 4 and thereafter in the driving system, and is mainly a total reduction ratio and a tire effective radius at that time. It is. The power running power of the motor 4 is the power consumption during power running, the representative efficiency is the motor efficiency in the most frequently used operation region, the reference power is the short-time rated power of the motor 4, and the output limit value is the battery capacity. The output value is limited by the above.

The larger of the two target engagement vehicle speeds calculated in this way is set as the target engagement vehicle speed cnvsp, and the value obtained by subtracting the margin vehicle speed cnvspM from that value is reset as a new target engagement vehicle speed cnvsp. (Steps 506 and 507). The margin vehicle speed corresponds to a correction amount for starting clutch engagement earlier than the actual vehicle speed in consideration of a required time from engine start to clutch engagement, and is set to, for example, about 4 km / h.

Next, when the target engagement vehicle speed cnvsp exceeds a predetermined upper limit value cnvspmax, cnvspm
ax, or cnvspmin when it is below the lower limit value cnvspmin, and finally the target engagement vehicle speed c.
It is reset as nvsp (step 508). Also,
When it is determined that the target driving force is in a deceleration state of zero or less (step 503), the target engagement vehicle speed is set to the upper limit value cnvspm.
ax is set (step 512). The upper limit value cnv
The spmax and the lower limit value cnvspmin are, for example, about 50 km / h and about 10 km / h, respectively.

Next, the actual vehicle speed Vsp becomes equal to the target engagement vehicle speed cnv.
sp or more, and cnvsp is the lower limit value cnvspm
If it is not equal to "in", an immediate engagement request is made to the clutch 3 on the condition that the state has continued for a predetermined time (for example, 100 msec) or more, and the clutch 3 is immediately engaged (steps 509 to 511). Otherwise, no clutch engagement request is issued (step 513). When the actual vehicle speed Vsp exceeds the upper limit value cnvspmax, the clutch 3 is engaged to avoid clutch wear due to excessive inward turning, while when the actual vehicle speed Vsp falls below the lower limit value cnvspmin, the clutch 3 is released to use the engine in an inefficient operating range. Try to avoid.

FIG. 6 shows an example of controlling the torques of the motors 1 and 4, the engine torque, and the rotational speed of the motor 4 and the engine 2 when the driving speed is switched from the motor 4 to the engine 2 when the vehicle speed becomes the target engagement vehicle speed. Show. As shown in the figure, at the time of the power switching, first, the engine 2 in the idle stop state is cranked and started completely by the motor 1,
After synchronizing the subsequent engine speed and the speed of the motor 4, an engagement command is issued to the clutch 3 to connect the engine 2 to the drive system. Subsequently, the torque applied to the drive system is smoothly shifted to the engine torque while adjusting the torque of the motor 4 and the motor 1. According to the above control, when the power is switched to the drive system, the clutch 3 starts the engagement operation earlier by an amount corresponding to the margin vehicle speed than when the actual vehicle speed reaches the target engagement vehicle speed. The time required for the switching operation up to the transition can be shortened, and an efficient running range by the engine running can be utilized accordingly, so that the fuel efficiency can be improved.

Next, the control contents of the embodiment relating to the clutch release control executed in the process of decreasing the vehicle speed are shown in FIG.
Shown in In this control, first, after detecting various operating states, it is determined whether the clutch 3 can be released (step 70).
1,702). In the determination of whether or not the clutch can be released, the current engagement state of the clutch 3 and the presence / absence of a release request are determined. If the current engagement state is no release request, the control loop is terminated without issuing a release request to the clutch 3 (step 7
13). In cases other than the above, the flow shifts to control for issuing an opening request after step 703.

When it is determined in the above determination process that the vehicle can be released, it is determined whether or not the vehicle is in a deceleration state from the result of calculating the target driving force of the vehicle (step 70).
3). When it is determined that the target driving force is greater than 0, that is, the vehicle is not in the deceleration state, the target open vehicle speed cnvspP of the clutch 3 based on the predicted motor power and the target open vehicle speed cnvspB of the clutch 3 based on the motor output limit value are calculated by the following equations. (Steps 704 and 705). Note that the target release vehicle speed of the clutch 3 is hereinafter simply referred to as the target release vehicle speed.

CnvspP = drive system representative value / motor 4 power running power predicted value / motor 4 representative efficiency / target drive force ... (3) cnvspB = drive system representative value / motor 4 reference power / motor 4 output limit value / target drive force (4) In the above equations (3) and (4), the drive system representative value, the representative efficiency of the motor 4, the reference power, and the output limit value are as described above. In this case, the predicted value of the motor 4 powering power is that the power of the vehicle is switched from the engine 2 to the motor 4 to shift to a running state using only the motor 4. This is a result of a prediction calculation based on a required driving force or the like.

The larger of the two target opening vehicle speeds calculated in this way is set as the target opening vehicle speed cnvsp, and the value obtained by subtracting the margin vehicle speed cnvspM from that value is reset as a new target engagement vehicle speed cnvsp. (Steps 706 and 707). The margin vehicle speed cnvspM in this case is for starting the clutch release operation slightly earlier than the actual vehicle speed reaches the target release vehicle speed, in anticipation of the operation response delay of the clutch 3 in the release operation.

Next, when the target opening vehicle speed cnvsp exceeds a predetermined upper limit value cnvspmax, cnvspm
ax, or cnvspmin when lower than the lower limit value cnvspmin, and finally the target open vehicle speed c.
It is reset as nvsp (step 708).

Next, the actual vehicle speed Vsp becomes equal to the target opening vehicle speed cnv.
sp or less, and the input-side rotation speed of the continuously variable transmission 5 (ie, the rotation speed of the motor 4) Npr is set to a predetermined reference value N
pro and the target driving force is equal to or less than the outputtable torque of the motor 4 (the predicted value of the maximum torque that can be output according to the electric power or the like at that time). The release request is output to the clutch 3 on condition that the condition has been satisfied for a predetermined time or more, and the clutch 3 is released (steps 709 to 711). Otherwise, no clutch release request is issued (step 71).
3). Here, the durability of the clutch is enhanced by regulating the number of revolutions after the clutch is released by the reference value Npro.

On the other hand, when it is determined in step 703 that the target driving force is in a deceleration state of zero or less, the actual vehicle speed Vs
All conditions that p is equal to or less than the upper limit value cnvspmax of the target open vehicle speed, that the target driving force is equal to or more than the regenerable torque, and that the input-side rotational speed Npr of the continuously variable transmission 5 is equal to or less than the reference value Npro are satisfied. When the established state continues for a predetermined time or more, the clutch is released (step 71).
2, 710, 711), the clutch release request is not made when the above condition is not satisfied (step 713).
The target driving force in this case means a negative torque corresponding to engine braking during deceleration. When the clutch is engaged, the actual engine braking action is used as it is, but when the clutch is released, the motor 4 is driven by the inertia force of the vehicle to generate electricity, and the power generation load (regenerative torque) at this time is applied to the engine. Use it like a brake. However, if the maximum value of the regenerative torque obtained by the motor 4 at the time of deceleration is less than the target driving force to provide an appropriate deceleration performance, that is, if an appropriate deceleration cannot be performed by the regenerative operation, the clutch release is canceled. This prevents fluctuations in the sense of deceleration.

[Brief description of the drawings]

FIG.

FIG. 2 is a schematic configuration diagram showing a configuration example of a hybrid vehicle to which the present invention can be applied.

FIG. 3 is a flowchart showing an outline of a first embodiment of control by the control circuit of the present invention.

FIG. 4 is a shift characteristic diagram showing an operation example according to the embodiment.

FIG. 5 is a flowchart showing an outline of another embodiment relating to clutch engagement control by the control circuit of the present invention.

FIG. 6 is a timing chart showing a control state of the rotation speed or torque of each unit at the time of power switching to which the clutch engagement control is applied.

FIG. 7 is a flowchart showing an outline of another embodiment relating to clutch release control by the control circuit of the present invention.

[Explanation of symbols]

 Reference Signs List 1 motor 2 engine 3 powder clutch 4 motor (rotary electric machine) 5 continuously variable transmission 9 hydraulic device 10 hydraulic pressure generating motor 15 battery 16 controller 19 DC / DC converter 20 key switch 21 select lever switch 22 accelerator pedal sensor 23 brake switch 24 Vehicle speed sensor 25 Battery temperature sensor 26 Battery SOC detection device 27 Engine speed sensor 28 Throttle opening sensor

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification FI FI Theme Court ゛ (Reference) F16H 61/02 // F16H 59:42 59:56 63:06 (72) Inventor Susumu Komiyama Yokohama City, Kanagawa Prefecture 2 at Takaracho, Kanagawa-ku Nissan Motor Co., Ltd. (72) Atsushi Shoji 2 at Takaracho, Kanagawa-ku, Yokohama City, Kanagawa Prefecture Nissan Motor Co., Ltd. F-term (reference) 3D039 AA01 AA02 AA04 AA19 AB27 AC07 AC34 AD01 AD06 AD44 AD53 3J052 AA09 AA17 CA05 CA12 CA21 CA32 FB01 FB31 GC32 GC46 GC64 GC72 GC73 HA11 HA17 KA01 LA01 5H115 PA12 PA15 PG04 PI16 PO17 PU02 PU08 PU22 PU25 PV02 PV09 QE10 QI04 QI09 QN06 QN12 RB08 RE01 RE02 RE05 RE20 SE04 TO05 SE01 TI03

Claims (6)

[Claims] 1. A drive system including a rotating electric machine for driving or regenerative power generation, a powder clutch for transmitting engine rotation to the driving system, and a stepless continuously changing reduction ratio of a driving system after the rotating electric machine. In a hybrid vehicle including a transmission and a control circuit that controls the powder clutch and the continuously variable transmission according to a vehicle driving state, the control circuit detects a temperature of the powder clutch, and the detected temperature is a set temperature. When the powder clutch is engaged in an operating state that exceeds the limit, the speed ratio of the continuously variable transmission is regulated so that the output rotation speed of the powder clutch is equal to or less than the set rotation speed, and then the powder clutch is quickly engaged. Control device for hybrid vehicle. 2. A drive system including a rotating electric machine for driving or regenerative power generation, a powder clutch for transmitting engine rotation to the drive system, and a control circuit for controlling the powder clutch according to a vehicle operating state. In the hybrid vehicle, when the control circuit shifts from a driving state in which the powder clutch is engaged and the engine output is transmitted to the drive system to a driving state in which the powder clutch is released and the rotating electric machine alone is used, the output side of the powder clutch is used. A control device for a hybrid vehicle configured to release a powder clutch when a rotation speed is equal to or lower than a set rotation speed. 3. A drive system including a rotating electric machine for driving or regenerative power generation, a powder clutch for transmitting engine rotation to the drive system, and a control circuit for controlling the powder clutch according to a vehicle operating state. In the hybrid vehicle, when the engine is stopped and the powder clutch is released and the vehicle is in a running state using only the rotating electric machine, and when the output rotation speed of the powder clutch becomes equal to or higher than a set rotation speed, the powder clutch is Control device for a hybrid vehicle having a configuration for fastening the vehicle. 4. A drive system including a rotating electric machine for driving or regenerative power generation, a powder clutch for transmitting engine rotation to the drive system, and a control circuit for controlling the powder clutch according to a vehicle operating state. In the hybrid vehicle, the control circuit starts the engine from the powder clutch disengaged state, synchronizes the engine speed with the powder clutch input side speed, and then engages the powder clutch. With respect to the target engagement vehicle speed of the powder clutch calculated from the vehicle speed, the powder is earlier than the actual vehicle speed reaches the target engagement vehicle speed by a period corresponding to a period from the engine start to the completion of rotation synchronization. A hybrid vehicle control device configured to output an engagement command to a clutch. 5. A drive system including a rotating electric machine for driving or regenerative power generation, a powder clutch for transmitting engine rotation to the drive system, and a control circuit for controlling the powder clutch according to a vehicle operating state. In the hybrid vehicle, the control circuit is configured to release the powder clutch and generate the deceleration torque only when the rotating electric machine is in a state where a required deceleration torque can be generated during deceleration in the powder clutch engagement state. Control device for hybrid vehicle. 6. A drive system including a rotating electric machine for driving or regenerative power generation, a powder clutch for transmitting engine rotation to the drive system, and a control circuit for controlling the powder clutch according to a vehicle operating state. In the hybrid vehicle, when the control circuit is running using the engine output with the powder clutch engaged, a power prediction value calculated on the assumption that the vehicle has run only with the required driving force and the rotating electric machine at that time. Is used to determine the target release vehicle speed of the powder clutch, and when the actual vehicle speed is equal to or lower than the target release vehicle speed and the required driving force can be achieved only by the rotating electric machine, the powder clutch is released and the required driving force is reduced. A control device for a hybrid vehicle configured to output power from a rotating electric machine and stop an engine.