JP2011011721A - Controller for hybrid electric vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a controller for a parallel hybrid electric vehicle, which is manufactured at low cost, while making an engine and a motor operate more efficiently.SOLUTION: The controller for a hybrid electric vehicle includes a manual clutch 13, interposed between an output shaft 11a of an engine 11 and a rotary shaft 12a of a motor-generator 12; a manual transmission 14 interposed between the motor-generator 12 and a driving wheel 18, whose input shaft 14a is connected to the rotary shaft 12a of the motor-generator 12; and a battery 19, which supplies a power to the motor-generator 12 and is charged with the generated energy of the motor-generator 12. The controller, further, includes a control means 24 which calculates motor torque, based on the operating state of a clutch 13 detected by a clutch state detection means 32a, the operating state of an accelerator detected by an accelerator state detection means 31a and the charging rate of a battery 19 detected by the charging rate detection means 23, and which controls the motor-generator 12 to generate the motor torque.

Description

  The present invention drives the vehicle by transmitting the output torque of the engine and the motor to the drive wheels via the manual transmission, and drives the vehicle by disconnecting the engine and transmitting the output torque of the motor to the drive wheels. The present invention relates to a parallel hybrid electric vehicle.

A parallel hybrid electric vehicle that can drive the vehicle by the output torque of both the engine (motor) and the electric motor has been developed, and the vehicle driving torque can be secured larger than that of the series type. It is put into practical use including large vehicles.
In such a parallel hybrid electric vehicle, as shown in FIG. 4, the output shaft (engine rotation shaft) of the engine 1 is equipped with an electric motor (usually a motor generator) 2, and the output shaft of the electric motor 2 (engine rotation) A shaft in which a transmission 4 is connected to a shaft 3 via a clutch 3 has been developed (see Patent Document 1). Here, the output shaft of the transmission 4 is connected to the drive wheels 8 via the propeller shaft 5, the differential 6, and the drive shaft 7. In the case of such a configuration, the parallel type can be obtained by simply adding the electric motor 2 to the rotating shaft of the engine 1 of the existing power train configured to transmit power in the order of the engine 1, the clutch 3, and the transmission 4. A hybrid electric vehicle can be constructed.

  Especially in the case of large vehicles such as trucks and buses, the output shaft of the engine is usually connected to the input shaft of the manual transmission via a manual clutch, so existing manual transmissions and manual clutches are used. However, the fact that it can be configured simply by adding an electric motor to the output shaft portion of the engine has great cost merit. However, since the engine and the electric motor are connected on the same axis and cannot be disconnected, the operation pattern is restricted. In other words, since the driving pattern is restricted, there are few merits to make the transmission and the clutch automatic.

  On the other hand, as shown in FIG. 5, an output shaft of the engine 1 is equipped with a rotating shaft of the electric motor 2 via the clutch 3 and an input shaft of the transmission 4 is directly connected to the rotating shaft of the electric motor 2 has been developed. (See Patent Document 2). Also in this case, the output shaft of the transmission 4 is connected to the drive wheels 8 via the propeller shaft 5, the differential 6 and the drive shaft 7. In the case of such a configuration, since the electric motor 2 is provided between the clutch 3 and the transmission 4, the configuration change with respect to the existing power train is large. However, since the engine 1 and the electric motor 2 are separated from each other and the vehicle can run with the driving force of the electric motor 2 alone, various operation patterns can be realized, and merits thereof are produced. For example, it is possible to start quietly and smoothly without using the engine 1, or to raise only the regenerative braking in which the electric motor 2 is in a power generation state without generating an engine brake, thereby increasing the regenerative efficiency. By making the transmission and the clutch automatic, this merit can be further utilized.

By the way, since the parallel hybrid electric vehicle of any structure shares the required vehicle driving torque (load torque) between the engine 1 and the electric motor 2, output control of the engine 1 and the electric motor 2 is required.
In Patent Document 1 relating to a configuration in which the engine 1 and the electric motor 2 in FIG. 4 are connected on the same shaft, the engine output is output at a constant rate corresponding to the charging rate (remaining capacity) of the battery with respect to the required vehicle driving torque. And a technique for sharing the output with the motor output. In other words, the engine 1 and the motor 2 normally share the load torque by 50%, and when the battery charge rate decreases, the load torque share of the engine 1 is 75% and the share of the motor 2 is reduced to 25%. .

  In Patent Document 2 in which the clutch 3 is interposed between the engine 1 and the electric motor 2 in FIG. 5, the mechanical automatic transmission 4 </ b> A is driven by the transmission 4 and the electric motor is driven by the clutch 3. The automatic clutch 3A is employed, and the engine 1, the electric motor 2, the mechanical automatic transmission 4A, and the automatic clutch 3A are controlled in cooperation. Further, if the battery charge rate is sufficient, the torque that can be generated by the electric motor 2 is used as much as possible for the required torque required for driving the vehicle when starting.

  As described above, the configuration shown in FIG. 5 can travel with the driving force of only the electric motor 2 and can realize various control patterns. Therefore, in the case of large vehicles such as trucks and buses, the above-mentioned patents are used. As in the literature 2, a mechanical automatic transmission 4A is used for the transmission 4, and an automatic clutch 3A driven by an electric motor is used for the clutch 3, and these are linked with the engine 1 and the electric motor 2. The advantage that the clutch 3 is interposed between the engine 1 and the electric motor 2 is effectively utilized.

  However, mechanical automatic transmissions and automatic clutches cause a significant cost increase compared to manual transmissions and manual clutches. For this reason, it is possible to manufacture a parallel hybrid electric vehicle that can be manufactured at a lower cost while using a manual transmission or a manual clutch, and can obtain the advantages of a system in which a clutch is interposed between an engine and an electric motor. Development is also required.

  Patent Document 3 describes a technique in which a vehicle equipped with a manual transmission is hybridized. In this technique, when the gear is pulled out, a reverse torque having the same magnitude as the engine torque is generated, and when the gear is put in, the input shaft rotational speed of the manual transmission is set to the rotational speed corresponding to the required gear stage. As described above, by controlling the operation state of the motor generator, it is possible to cope with a manual shift operation in a state where the input shafts of the engine, the motor generator, and the manual transmission are directly connected.

  In this technology, a clutch is not indispensable between the engine and the motor generator or between the motor generator and the manual transmission, but a configuration in which a clutch is interposed between each of these is also described. (FIG. 8 of Patent Document 3).

JP 2002-252904 A JP 2007-261415 A JP 2001-352605 A

In the technique of the above-mentioned Patent Document 3, a vehicle equipped with a manual transmission device is hybridized. However, there is no description of a technique that specifically considers the case of using a manual type not only for the transmission but also for the clutch.
As described above, in order to manufacture a parallel hybrid electric vehicle at a lower cost while being able to realize various driving patterns, in the one shown in FIG. The manual clutch 3 is interposed between the engine 1 and the electric motor 2 and the electric motor 2 and the manual transmission 4 are directly connected to each other. Therefore, it is necessary to control the engine 1 and the electric motor 2 so that the advantage that the clutch 3 is interposed therebetween can be made more effective.

  The present invention was devised to solve this problem, and is a parallel hybrid that can operate the engine and the electric motor more efficiently while being able to manufacture a hybrid electric vehicle at a low cost. An object of the present invention is to provide a control device for an electric vehicle.

  The present invention was devised to achieve the above-described object, and a control device for a parallel hybrid electric vehicle according to the present invention includes an engine mounted on a vehicle, a motor generator mounted on the vehicle, and A manual clutch interposed between the output shaft of the engine and the rotating shaft of the motor generator, and a rotating shaft of the motor generator interposed between the motor generator and the driving wheel. A manual transmission that is coupled to the input shaft to transmit the driving force of the engine and / or the motor generator to the drive wheels, and when the motor generator operates as a motor, electric power is supplied to the motor generator. And a battery that is charged with the electric power generated by the motor generator when the motor generator operates as a generator. Detected by the clutch state detecting means for detecting the operation state, the accelerator state detecting means for detecting the operation state of the accelerator of the vehicle, the charging rate detecting means for detecting the charging rate of the battery, and the clutch state detecting means The motor generator should be generated based on the operation state of the clutch, the operation state of the accelerator detected by the accelerator state detection means, and the charge rate of the battery detected by the charge rate detection means. And a control means for calculating the motor torque and controlling the motor generator so that the motor torque is generated.

  The control means sets a clutch-corresponding torque coefficient based on the operation state of the clutch, sets an accelerator-corresponding torque coefficient based on the operation state of the accelerator pedal, and determines a charge rate-corresponding torque based on the charging rate of the battery. By setting a coefficient and multiplying the maximum torque that can be generated by the motor generator by the torque coefficient corresponding to the clutch, the torque coefficient corresponding to the accelerator, and the torque coefficient corresponding to the charging rate, It is preferable to calculate.

In this case, it is preferable that the accelerator-corresponding torque coefficient is set so as not to become 0 even when the accelerator is in a non-operating state.
Further, the control means calculates a vehicle request torque based on a depression state of the accelerator pedal, and when the vehicle request torque is insufficient with the electric motor torque, an engine torque corresponding to the shortage is generated. It is preferable to control the engine.

According to the parallel hybrid electric vehicle of the present invention, when the manual clutch is connected, the output torques of both the engine and the motor generator are shifted through the manual transmission and transmitted to the drive wheels. . For this reason, a large vehicle driving force can be secured by using both output torques of the engine and the motor generator.
On the other hand, when the manual clutch is released, power transmission between the engine and the motor generator is cut off, and only the motor generator is shifted through the manual transmission and is connected to the drive wheels. Therefore, for example, when starting, it is possible to start quietly and without releasing exhaust gas without releasing the clutch and using the output torque of only the motor generator to operate the engine. Further, for example, during braking, it is possible to perform braking while recovering the maximum amount of energy by exerting a large regenerative braking force by the power generation load using the motor generator as a generator without releasing the clutch and operating the engine brake.

  And according to the control apparatus for a parallel hybrid electric vehicle of the present invention, the control means is an electric motor that the motor generator should generate based on the operation state of the clutch, the operation state of the accelerator, and the charging rate of the battery. Since the torque is calculated and the motor generator is controlled so that the motor torque is generated, the motor generator can be operated as an electric motor with high efficiency and good feeling.

  That is, in a vehicle having only a normal engine, the drive torque output from the engine to the drive wheel side changes according to the operation state when the clutch is operated (release operation). In contrast, in this hybrid electric vehicle, since the rotating shaft of the motor generator is coupled to the input shaft of the manual transmission, if the driving torque of the motor generator is generated, the clutch is operated. However, unless the manual transmission is in the neutral state, the motor torque is directly output to the drive wheels via the manual transmission, giving a sense of incongruity.

  In this respect, for example, by setting the motor torque to be smaller as the clutch is operated to the disengagement side depending on the clutch operation state, the torque output to the drive wheel side is provided with only a normal engine. The torque feeling is similar to that of a vehicle equipped with only a normal engine. At the same time, unnecessary motor torque is also suppressed.

Also, according to the operating state of the accelerator, for example, by setting the motor torque to be larger as the accelerator is operated to the torque request side, the motor torque can be set to an appropriate magnitude, and The motor generator can be operated as an electric motor with good feeling.
Further, according to the charging rate of the battery, for example, by setting the motor torque to be smaller as the charging rate of the battery becomes smaller, the motor is protected while suppressing the excessive decrease in the charging rate of the battery and protecting the battery. Torque can be used.

  Also, the maximum torque that can be generated by the motor generator is set by setting the clutch compatible torque coefficient based on the clutch operating state, the accelerator corresponding torque coefficient based on the accelerator pedal operating state, and the charging rate corresponding torque coefficient based on the battery charging rate. If the motor torque is calculated by multiplying each of the coefficients, the motor torque can be calculated easily and appropriately with simple logic.

By setting the accelerator-corresponding torque coefficient so that it does not become zero even when the accelerator is not operated, it is possible to travel at a low speed only by operating the clutch without operating the accelerator. It is possible to improve the fine movement operability when starting.
Further, the vehicle required torque is calculated based on the depression state of the accelerator pedal, and when the vehicle required torque is insufficient with the motor torque, the engine is controlled so that the engine torque is generated by the shortage. The driving torque of the vehicle according to the torque request can be generated, and the drivability of the vehicle can be improved.

It is a typical block diagram which shows the control apparatus of the parallel hybrid electric vehicle which concerns on one Embodiment of this invention with a power train. It is a block diagram explaining the functional structure of the control apparatus of the parallel hybrid electric vehicle which concerns on one Embodiment of this invention. It is a figure explaining the clutch stroke which concerns on one Embodiment of this invention. It is a typical block diagram of the power train of the 1st conventional parallel hybrid electric vehicle. It is a typical block diagram of the power train of the 2nd conventional parallel hybrid electric vehicle.

Hereinafter, a control apparatus for a parallel hybrid vehicle according to an embodiment of the present invention will be described with reference to the drawings.
[Vehicle powertrain configuration]
FIG. 1 is a schematic configuration diagram showing a control apparatus for a parallel hybrid electric vehicle according to the present embodiment together with a power train. As shown in FIG. 1, in this hybrid vehicle, a rotary shaft 12a of a motor generator (hereinafter also simply referred to as “motor”) 12 is connected to an output shaft (rotary shaft) 11a of an engine (prime mover) 11 via a clutch 13. It is equipped as a parallel hybrid vehicle in which the input shaft 14a of the transmission 14 is directly connected to the rotating shaft 12a of the electric motor 12. In addition, a manual clutch is used for the clutch 13 and a manual transmission is used for the transmission 14. The output shaft 14 b of the transmission 14 is connected to the left and right drive wheels 18 via a propeller shaft 15, a differential 16 and a drive shaft 17.

Therefore, when the clutch 13 is connected, both the output shaft 11a of the engine 11 and the rotating shaft 12a of the electric motor 12 are mechanically connected to the drive wheels 18, and when the clutch 13 is disconnected, the rotating shaft of the electric motor 12 is connected. Only 12 a is mechanically connected to the drive wheel 18.
The electric motor 12 operates as an electric motor (motor) when the DC power stored in the battery 19 is converted into AC power by the inverter 20 and supplied, and the driving force is shifted to an appropriate speed by the transmission 14. It is transmitted to the drive wheel 18 later. When the vehicle decelerates, the electric motor 12 operates as a generator, and kinetic energy generated by the rotation of the drive wheels 18 is transmitted to the electric motor 12 via the transmission 14 and converted into AC power, thereby generating regenerative braking force. The AC power is converted into DC power by the inverter 20 and then charged to the battery 19, and the kinetic energy generated by the rotation of the drive wheels 18 is recovered as electric energy.

  On the other hand, the driving force of the engine 11 is transmitted to the transmission 14 via the rotating shaft 12a of the electric motor 12 when the clutch 13 is connected, and is transmitted to the drive wheels 18 after being shifted to an appropriate speed. It is like that. Accordingly, when the electric motor 12 operates as a motor when the driving force of the engine 11 is transmitted to the driving wheels 18, the driving force of the engine 11 and the driving force of the electric motor 13 are transmitted to the driving wheels 18, respectively. . That is, a part of the driving torque to be transmitted to the driving wheels 18 for driving the vehicle is supplied from the engine 11 and the remaining part is supplied from the electric motor 12.

  When the charging rate (hereinafter referred to as SOC) of the battery 19 is reduced and the battery 19 needs to be charged, the electric motor 12 operates as a generator, and the electric motor 12 is operated using a part of the driving force of the engine 11. Electricity is generated by driving, and the generated AC power is converted into DC power by the inverter 20 and then the battery 19 is charged.

[Configuration of control system for powertrain]
An engine ECU 21 is provided for controlling the engine 11, an inverter ECU 22 is provided for controlling the inverter 20, and a battery ECU 23 is provided for controlling the battery 1, and the vehicle is passed through these engine ECU 21, inverter ECU 22, and battery ECU 23. A vehicle ECU 24 is provided for integrated control. Each of the ECUs 21 to 24 is a computer including a memory (ROM, RAM), a CPU, and the like.

The vehicle ECU (control means) 24 performs various operations such as the control state, start of the vehicle, acceleration, and deceleration in accordance with the operation state of the vehicle and the engine 11 and information from the engine ECU 21, the inverter ECU 22, and the battery ECU 23. Integrated control for appropriately operating the engine 11 and the electric motor 12 according to the state is performed.
At this time, the vehicle ECU 24 sets a torque to be generated by the engine 11 (engine torque) and a torque to be generated by the electric motor 12 (electric motor torque). The torque to be generated by the electric motor 12 is a positive value when the motor 12 is operated by a motor, and is a negative value when the electric generator 12 is operated.

  The engine ECU 21 performs various kinds of control necessary for the operation of the engine 11 itself, such as start / stop control of the engine 11, idle control, or regeneration control of an exhaust gas purification device (not shown), and the engine set by the vehicle ECU 24. The fuel injection amount and injection timing of the engine 11 are controlled so that the engine 11 generates the torque required for the engine 11 (engine torque).

The inverter ECU 22 controls the operation of the motor 12 by operating the motor 12 or the generator by controlling the inverter 20 based on the torque (motor torque) that should be generated by the motor 12 set by the vehicle ECU 24.
The battery ECU (battery charge rate detection means) 23 detects the temperature of the battery 19, the voltage of the battery 19, the current flowing between the inverter 20 and the battery 19, and the SOC of the battery 19 is determined from these detection results. The obtained SOC is sent to the vehicle ECU 24 together with the detection result.

  Further, an accelerator operating state, that is, an accelerator pedal position sensor (accelerator state detecting means, hereinafter also referred to as “APS”) 31a for detecting an accelerator pedal 31 depression amount (accelerator opening) AP, and a clutch operating state, That is, a clutch stroke sensor (clutch state detection means) 32a for detecting the depression amount (clutch stroke) CS of the clutch pedal 32 is further provided, and each detection information from the APS 31a and the clutch stroke sensor 32a and the battery charging rate are provided. The SOC information from the battery ECU 23 as detection means is sent to the vehicle ECU 24.

When the vehicle is driven, the vehicle ECU 24 calculates the motor torque Tm and the engine torque Te based on the accelerator opening AP, the clutch stroke CS, and the charging rate SOC, as shown in FIGS. Each torque is output to the engine ECU 21 and the inverter ECU 22.
Here, calculation of the motor torque Tm and the engine torque Te by the vehicle ECU 24 will be described. Based on the accelerator opening AP, the vehicle ECU 24 calculates a torque (vehicle required torque) Ta required for the vehicle corresponding to an increase in the accelerator opening AP (for example, proportional to the vehicle) (vehicle required torque calculation). Part) 24a.

Further, the vehicle ECU 24 calculates the motor torque Tm based on the maximum torque Tm _MAX that can be generated by the electric motor 12, the clutch stroke CS, the accelerator pedal opening AP, and the charging rate SOC. That is, the vehicle ECU 24 calculates the clutch-corresponding torque coefficient C _CS that decreases as the clutch stroke CS increases (that is, as the clutch pedal is depressed and the operation amount toward the disengagement side of the clutch increases). functional elements and (clutch corresponding torque coefficient calculating unit) 24b, functional element for calculating the accelerator response torque coefficient C _AP that increases with an increase in the accelerator opening AP based on the accelerator opening degree AP (accelerator-based torque coefficient calculation unit) 24c, and a functional element (a charge rate corresponding torque coefficient calculating unit) 24d that calculates a charge rate corresponding torque coefficient C _SOC that decreases as the charge rate SOC decreases.

Note that the clutch-corresponding torque coefficient C _CS is “1” when the clutch stroke CS is 0% (maximum depression amount), and the clutch stroke CS becomes large (that is, the clutch pedal 32 is depressed, and the clutch engagement). It is set to be “0” when the clutch stroke CS is 100% (maximum depression amount).

  However, “play” is provided in the vicinity of 0% and 100% of the clutch stroke CS, and in actuality, when the clutch pedal 32 is slightly depressed, the clutch 13 is in a fully engaged state. The clutch 13 is completely disengaged before the clutch pedal 32 is fully depressed. Therefore, the clutch stroke sensor 32a corresponds to this, and even if the clutch pedal 32 is slightly depressed, the region where the clutch 13 is kept in the fully engaged state outputs 0% as the clutch stroke CS. 100% is output as the clutch stroke CS from the front by a predetermined amount from the maximum stroke. The clutch stroke CS will be further described later.

Also, the accelerator corresponds torque coefficient C _AP, increases as if the accelerator pedal 31 is depressed "0", the accelerator pedal 31 is gradually depressed, the accelerator pedal 31 is depressed to the vicinity of the maximum depression amount "1 " Also in this case, “play” is provided in the minimum area (opening degree 0%) and the maximum area (opening degree 100%) of the accelerator opening degree, and the accelerator-corresponding torque coefficient C is obtained only when the accelerator pedal 31 is depressed slightly. _AP is set to “0”, and is set to “1” slightly before the accelerator pedal 31 reaches the maximum depression amount.

In addition, since it can be seen that the torque correction corresponding to the accelerator operation limits the motor torque as the accelerator operation is smaller, from this point of view, the coefficient (1-C _AP ) corresponding to the accelerator-corresponding torque coefficient C _AP. Can also be referred to as a torque limiting coefficient.
Regarding the charge rate corresponding torque coefficient C _SOC , assuming that the _SOC of the battery 16 is 100%, the battery 19 is in an overdischarged state when the SOC of the battery is, for example, 30% or less. In this region, the charge rate corresponding torque coefficient C _{SOC is set} to “0”. Further, when the SOC of the battery 19 is, for example, 70% or more, the battery 19 may be in an overcharged state. Therefore, the charge rate corresponding torque coefficient C _{SOC is set} to “1” as the region where the battery 19 should be discharged. To do. When the SOC is between 30% and 70%, the charging rate corresponding torque coefficient C _SOC is increased as the _SOC increases.

Then, as shown in the following equation (1), the vehicle ECU 24 multiplies the maximum torque Tm _MAX that can be generated by the electric motor 12 by these coefficients C _CS , C _AP , and C _SOC to calculate the electric motor torque calculation value Tm. A functional element (motor torque calculation unit) 24e for calculating _C is further provided. The maximum torque Tm _MAX that can be generated by the electric motor 12 is a known value due to the use of the electric motor 12.
Tm _C = Tm _MAX × C _CS × C _AP × C _SOC (1)
Further, the vehicle ECU 24 includes a function (torque setting unit) 24f for setting the motor torque Tm and the engine torque Te. The torque setting unit 24f compares the motor torque calculation value Tm _C with the vehicle required torque Ta to determine the motor torque. When the calculated value Tm _C exceeds the vehicle required torque Ta, the motor torque Tm is limited to the vehicle required torque Ta (Tm = Ta), and when the motor torque calculated value Tm _C does not exceed the vehicle required torque Ta, The motor calculated value torque Tm _C is set to the motor torque Tm (Tm = Tm _C ).

Further, when the motor torque calculation value Tm _C does not exceed the vehicle request torque Ta, the torque setting unit 24f subtracts the motor torque Tm (= Tm _C ) set at this time from the vehicle request torque Ta. The torque Te (= Ta−Tm).
Incidentally, SOC of the battery 19 is sufficient (e.g. 70% or more) to the precondition, the vehicle required torque Ta required when the accelerator pedal opening AP is the predetermined opening AP ₀ or less that is set in advance Normally, it is assumed that the motor torque calculation value Tm _C satisfies the vehicle required torque Ta.

  Thus, the electric motor torque Tm set by the vehicle ECU 24 is output to the inverter ECU 22, and the inverter ECU 22 controls the electric motor 12 so that the set electric motor torque Tm is generated. The engine torque Te set by the vehicle ECU 24 is output to the engine ECU 21, and the engine ECU 21 controls the engine 11 so that the set engine torque Te is generated.

  By the way, in this embodiment, further “play” is provided in the vicinity of the maximum depression region of the clutch pedal 32 in addition to the conventional “play”. In other words, when the clutch pedal is depressed from the fully engaged state (ie, the fully engaged state) where the depression amount (ie, clutch stroke CS) is 0 (ie, when the clutch stroke CS is applied), the clutch pedal slips from the completely engaged state. A half-clutch state (half-engaged state) is engaged, and as the clutch stroke CS is further increased, the slip in the half-clutch state increases, and eventually the coupling is completely released (disengaged state). Or clutch disengaged state).

  Normally, “play” is provided so that the clutch pedal can be depressed to some extent even if it is depressed to the disengaged state in this way, and it is set so that the clutch disengaged state can be surely realized even with changes over time of the clutch However, in this embodiment, as shown in FIG. 3, this “play” area is enlarged than usual, and the driver can use this “play” area to perform a specific driving operation. It is like that.

That is, the clutch stroke sensor 32a assumes that the added "play" area is actually less than 100% of the clutch stroke although the clutch 13 is in the disengaged state. When the “play amount” area provided conventionally is reached, the clutch stroke is set to output 100%. Therefore, in the added “play” region, the clutch stroke becomes less than 100%, and the clutch-corresponding torque coefficient _CCS is generated as a value larger than zero.

The clutch stroke corresponding to the added “play” area is, for example, 70 to 100%. When the clutch stroke is at a value (70 to 100%) corresponding to the added “play” region, the vehicle ECU 24 sends a control signal to the engine ECU 21 so that the engine 11 is stopped or idling. Output. In this case, for example, that the SOC is sufficient to (SOC 70% or higher) Prerequisites and accelerator opening increment in accelerator opening AP is less than a predetermined opening degree AP ₁ that is set in advance (per unit time If the increase amount ΔAP is equal to or less than the predetermined increase amount ΔAP ₀ set in advance, the engine 11 may be stopped, and if not, the engine 11 may be idling. The predetermined opening degree AP ₁ of the case, the predetermined opening AP ₀ and equal to or smaller than the predetermined opening AP ₀ of the aforementioned above.

  The vehicle ECU 24 detects that a braking operation is being performed based on information from a brake sensor (not shown) that detects a brake operation (for example, a depression operation of a brake pedal, a brake fluid pressure, etc.) during braking of the vehicle. During the braking operation, the brake operation amount is determined based on information from a brake operation amount sensor (not shown) that detects the brake operation amount (for example, the depression amount of the brake pedal) by operating the electric motor 12 through the inverter ECU 22. Regenerative braking force is generated according to At this time, the battery 19 is charged with generated power obtained by regenerative braking.

  Further, when the clutch 13 is operated together with the brake operation during braking of the vehicle, when the clutch 13 slips, the engine brake is not used by the amount of the slip, and when the clutch 13 is completely disengaged, The engine brake will not work at all. In this way, in the vehicle ECU 24, when the clutch 13 is operated during the brake operation, the electric motor 12 passes through the inverter ECU 22 so as to increase the regenerative braking force by the reduction amount of the engine brake generated according to the clutch stroke CS. Control the state of generator operation. If the clutch stroke CS is adjusted to the “play” region (the conventional “play” region and the added “play” region) as shown in FIG. 3, the engine brake applied when the clutch 13 is fully engaged. Since all the minutes are replaced by the regenerative braking force, the regenerative braking is performed more efficiently.

  Further, in the vehicle ECU 24, when the SOC is lower than a sufficient range (SOC is 70% or more), the vehicle request is made even when the predetermined condition, for example, the vehicle request torque Ta is not more than a predetermined value set in advance and only the engine torque Te is used. When there is a sufficient margin with respect to the torque Ta, the motor 12 is operated as a generator through the inverter ECU 22, and the motor 12 is rotationally driven with a part of the engine torque Te to generate power. The battery 19 is charged with the generated power thus obtained, and the SOC is recovered.

[Action]
Since the control device for a parallel hybrid vehicle according to an embodiment of the present invention is configured as described above, the parallel hybrid vehicle is operated as follows through the control of the ECUs 21 to 24 including the vehicle ECU 24. Can do.
<At departure>
In the present hybrid vehicle, since both the clutch 13 and the transmission 14 are manual type, at the time of starting, the clutch pedal 32 is depressed to disengage the clutch 13, the transmission 14 is put into the starting stage, and the accelerator pedal 31. The pedal of the clutch pedal 32 is gradually released while the pedal is depressed. When releasing the depression of the clutch pedal 32, the clutch 13 is actually in a disengaged state by utilizing the added "play" area, and the engine 11 is connected to the electric motor 12 and the speed change gear. Although it is disconnected from the machine 14, the motor generates torque with the clutch-corresponding torque coefficient _CCS being larger than zero.

Therefore, when the accelerator pedal 31 is depressed while adjusting the clutch pedal 32 to the added “play” region, as long as the charging rate SOC is ensured, the clutch-corresponding torque coefficient C _CS , the accelerator-corresponding torque coefficient C _AP , the charging Any of the rate-corresponding torque coefficients C _SOC becomes larger than 0, and a motor torque calculation value Tm _C is generated. Thus, the motor 14 is commanded to the motor torque Tm according to the motor torque calculation value Tm _C, and the motor torque Tm generated by the motor 14 can start without requiring the engine torque Te.

At this time, SOC of the battery 19 is sufficient (e.g. 70%), then whether or accelerator pedal opening AP to operate larger than the predetermined opening degree AP ₁ of the accelerator opening AP than a predetermined increase amount .DELTA.AP ₀ If the operation is rapidly increased, the clutch 13 is in the disengaged state, but the engine 11 limits the engine torque so as to maintain the low load torque and increases only the generated torque of the electric motor. When the SOC of the battery 19 is not sufficient (for example, less than 30%), the engine torque restriction is canceled regardless of the accelerator opening AP, and the engine torque equivalent to that of a normal vehicle is generated to start.

During starting, when the increase in the operation of the accelerator pedal opening AP the engaging operation of the clutch 13, the vehicle required torque Ta is increased around the accelerator opening AP exceeds a predetermined opening AP ₀ set in advance, the electric motor The torque calculation value Tm _C cannot satisfy the vehicle request torque Ta. However, at this time, since the engine 11 that has been idling in advance is controlled so as to generate the engine torque Te that does not satisfy the vehicle required torque Ta by the electric motor torque calculation value Tm _C , the electric motor 12 and the engine 11 are controlled. The vehicle required torque Ta is generated in cooperation with each other, and when starting, the driver's torque request can be answered using the motor torque Tm as much as possible.

<During normal driving>
During traveling after starting, a speed change operation, that is, a speed change operation of the transmission is performed while manually operating the clutch 13 and the transmission 14 as necessary. Unless the change operation is performed, the clutch 13 is not operated (the clutch stroke is 0%) and the clutch is fully engaged, and the clutch-corresponding torque coefficient _CCS is “1”. Therefore, the motor torque calculation value Tm _C is calculated according to the accelerator-corresponding torque coefficient C _AP and the charging rate-corresponding torque coefficient C _SOC , the motor torque Tm is set, and the motor 12 is controlled to output the motor torque Tm. The Further, when the vehicle required torque Ta is not satisfied with the electric motor torque Tm, the engine 11 is controlled so as to generate the engine torque Te corresponding to the difference. As a result, the engine torque Te and the motor torque Tm are transmitted at a predetermined speed ratio through the transmission 14 through the engaged clutch 13 and transmitted to the drive wheels 18. If the electric motor torque calculation value Tm _C satisfies the vehicle request torque Ta, the engine 11 is stopped or idling as described above.

Further, when a change operation is performed during traveling, first, the clutch 13 is disengaged. As a result, the clutch-corresponding torque coefficient _CCS becomes zero, so the motor torque calculation value Tm _C also becomes zero, and the motor torque Tm becomes zero. That is, the electric motor 14 is controlled so that no torque is applied to the drive system and no load is applied to the drive system.
Then, after changing operation of the gear position, it will be joined clutch 13, but at this time, since the clutch stroke with the joining operation of the clutch 13 decreases, the clutch corresponding torque coefficient C _CS is approaching from 0 to 1 Go. Therefore, the motor torque calculation value Tm _C is calculated according to the accelerator-corresponding torque coefficient C _AP and the charging rate-corresponding torque coefficient C _SOC , the motor torque Tm is set, and the motor 12 is controlled to output the motor torque Tm. The

If the calculated motor torque Tm _C does not exceed the vehicle required torque Ta, the value obtained by subtracting the motor torque Tm (= Tm _C ) set at this time from the vehicle required torque Ta is set to the engine torque Te (= Ta− Tm), the set engine torque Te is also output, and the engine torque Te and the motor torque Tm are speed-changed at a predetermined speed ratio via the transmission 14 through the engaged clutch 13, and the drive wheels 18 is transmitted. If the electric motor torque calculation value Tm _C satisfies the vehicle request torque Ta, the engine 11 is stopped or idling as described above.

<When driving at slow speed (when driving on a congested road)>
When driving on a congested road where the traveling road is congested and repeats slow speed driving and stopping, the driver sets the gear position of the transmission 14 to a low speed gear and adds the clutch 13 as shown in FIG. While adjusting to the “play” area, the accelerator operation is performed to drive at a slow speed, the clutch 13 is disengaged, the clutch-corresponding torque coefficient _CCS is set to be greater than 0, and the clutch-corresponding torque coefficient C _The motor 12 is controlled so as to output the motor torque Tm by setting the motor torque calculation value Tm _C calculated according to _CS , the accelerator corresponding torque coefficient C _AP and the charging rate corresponding torque coefficient C _SOC to the motor torque Tm. The vehicle can travel at a slow speed.

If it is desired to stop the vehicle, the state in which the clutch 13 is adjusted to the added “play” region as shown in FIG. 3 is maintained, and the vehicle is stopped by stopping the accelerator operation and performing the brake operation. Can do. At this time, since the accelerator-corresponding torque coefficient C _AP is 0, the motor torque calculation value Tm _C , that is, the motor torque Tm is also 0, and the motor 14 does not apply torque to the drive system, and the drive It is controlled so that it does not become a load on the system. The engine 11 is stopped or idling as described above.

<During braking during normal driving>
As described above, when braking the vehicle, the electric motor 12 is operated as a generator to generate a regenerative braking force corresponding to the amount of brake operation, and the battery 19 is charged by the generated power obtained by this regenerative braking. When the clutch 13 is operated together with the brake operation, the state of the generator operation of the electric motor 12 is controlled so that the regenerative braking force is increased by the reduction amount of the engine brake generated accordingly. Therefore, when the vehicle is braked, an engine that is applied when the clutch 13 is completely engaged can be obtained by adjusting the “play” region (the conventional “play” region and the added “play” region) as shown in FIG. Since all the brake components are replaced with the regenerative braking force, the regenerative braking force is increased to the maximum to achieve more efficient regenerative braking, and the battery 19 can be charged with the electric power generated by the regenerative braking.

〔effect〕
As described above, when the clutch 13 is released, the power transmission between the engine 11 and the electric motor 12 is cut off, and only the electric motor 12 is drivingly connected to the drive wheels 18 via the transmission 14, so that In addition, when the vehicle is started, it is possible to start quietly without releasing or suppressing exhaust gas without releasing the clutch 13 and using the output torque (motor torque) of only the motor 12 to operate the engine 11. Become.
Further, at the time of braking, it is possible to perform braking while recovering the maximum energy by demonstrating a large regenerative power by the power generation load using the electric motor 12 as a generator without releasing the clutch 13 and operating the engine brake. Efficiency can be improved.

Further, the motor torque Tm is calculated based on the clutch stroke (operation state of the clutch 13) CS, the accelerator opening (accelerator operation state) AP, and the charging rate SOC of the battery 19, and the motor torque Tm is calculated. Since the electric motor 12 is controlled to be generated, the motor generator 12 can be operated as an electric motor with good efficiency and good feeling.
That is, in this hybrid electric vehicle, since the rotating shaft 12a of the electric motor 12 is coupled to the input shaft 14a of the transmission 14, if the electric motor torque Tm is generated, even if the clutch 13 is operated, the transmission 14 Unless the motor is in the neutral state, the motor torque Tm is output to the drive wheels 18 through the transmission 14 as it is, giving a sense of incongruity. However, depending on the clutch operating state, the motor torque Tm decreases as the clutch 13 is operated to the disengagement side, and the torque output to the drive wheel 28 side is changed in the same manner as in a vehicle having only a normal engine. The torque feeling is the same as that of a vehicle having only a normal engine. At the same time, unnecessary motor torque Tm is also suppressed.

Further, since the motor torque Tm increases as the accelerator pedal is depressed in accordance with the operation state of the accelerator, the motor torque Tm can be set to an appropriate magnitude. Also in this respect, the efficiency and the feeling are good. The motor generator 12 can be operated as a motor.
Furthermore, the motor torque Tm decreases as the charge rate SOC decreases in accordance with the charge rate SOC of the battery 19. Therefore, the motor torque Tm is used while protecting the battery while suppressing an excessive decrease in the battery charge rate SOC. It becomes possible to do.

In addition, the clutch-corresponding torque coefficient C _CS based on the operating state of the clutch 13, the accelerator-corresponding torque coefficient C _AP based on the operating state of the accelerator pedal 31, and the charging rate-corresponding torque coefficient C _SOC based on the battery charging rate SOC are set, respectively. Since the motor torque Tm _C is calculated by multiplying each of the coefficients C _CS , C _AP , and C _SOC by the maximum torque Tm _MAX that can be generated by the generator 12, the motor can be easily and appropriately operated with simple logic. Torque Tm _C can be calculated.

  Further, the vehicle required torque Ta is calculated based on the depressed state of the accelerator pedal 31, and when the vehicle required torque Ta is insufficient with the motor torque Tm, the engine 11 is controlled so that the engine torque Te is generated by the shortage. By doing so, it is possible to generate the driving torque of the vehicle according to the torque request of the driver while using the electric motor torque Tm as much as possible, and to improve the drivability of the vehicle.

In addition, since the manual clutch 13 and the manual transmission 14 are applied, the frequency of use of the electric motor 12 required for a hybrid electric vehicle can be improved while reducing the manufacturing cost of the vehicle, and various types associated therewith. The practical performance can be improved.
[Others]
Although the embodiment of the present invention has been described above, the present invention is not limited to the embodiment, and can be implemented by appropriately changing the embodiment without departing from the gist of the present invention. Is.

For example, in the above embodiments, the accelerator corresponds torque coefficient C _AP, the accelerator is not operated, i.e., if the accelerator opening AP is zero, but is set to the accelerator response torque coefficient C _AP is 0, the accelerator Even in the non-operating state, as long as the brake operation is not performed, the accelerator-corresponding torque coefficient _CAP may be set to a value larger than 0 (for example, 0.05). Of course, also in this case, the accelerator response torque coefficient C _AP increases the accelerator pedal 31 is gradually depressed, is when the accelerator pedal 31 is depressed to the vicinity of the maximum depression amount "1".

With this configuration, even if the accelerator is not operated, the clutch stroke CS reaches 100% and the clutch-corresponding torque coefficient _CCS becomes 0, or the battery 19 is in an overdischarged state (the battery SOC is, for example, 30% or less). As long as the charging rate corresponding torque coefficient C _SOC does not become zero, the motor torque calculation value Tm _C is generated, and the motor torque Tm can be set effectively. For this reason, it is possible to travel at a low speed only by operating the clutch without operating the accelerator. For example, it is possible to easily travel at a low speed in a traffic jam and to improve the fine movement operability at the time of start.

11 Engine (Motor)
11a Output shaft (rotary shaft) of engine 11
13 Manual clutch 12 Motor generator (motor)
12a Rotating shaft of the motor generator 12 14 Manual transmission 14a Input shaft 14b of the transmission 14b Output shaft of the transmission 14 15 Propeller shaft 16 Differential 17 Drive shaft 18 Drive wheel 19 Battery 20 Inverter 21 Engine ECU
22 Inverter ECU
23 battery ECU (battery charge rate detection means)
24 vehicle ECU
31a Accelerator pedal position sensor (accelerator state detection means)
32a Clutch stroke sensor (clutch state detection means)

Claims (4)

An engine mounted on the vehicle,
A motor generator mounted on the vehicle;
A manual clutch interposed between the output shaft of the engine and the rotating shaft of the motor generator;
A manual is interposed between the motor generator and the drive wheel, and an input shaft is coupled to a rotation shaft of the motor generator to transmit the driving force of the engine and / or the motor generator to the drive wheel. Type transmission,
A battery that supplies electric power to the motor generator when the motor generator operates as a motor, and is charged with power generated by the motor generator when the motor generator operates as a generator. A control device for a parallel hybrid electric vehicle,
Clutch state detecting means for detecting an operation state of the clutch;
An accelerator state detecting means for detecting an operation state of the accelerator of the vehicle;
Charging rate detecting means for detecting the charging rate of the battery;
Based on the operation state of the clutch detected by the clutch state detection means, the operation state of the accelerator detected by the accelerator state detection means, and the charge rate of the battery detected by the charge rate detection means A parallel hybrid electric vehicle comprising: control means for calculating a motor torque to be generated by the motor generator and controlling the motor generator so that the motor torque is generated. Control device. The control means sets a clutch-corresponding torque coefficient based on the operation state of the clutch, sets an accelerator-corresponding torque coefficient based on the operation state of the accelerator pedal, and determines a charge rate-corresponding torque based on the charging rate of the battery. By setting a coefficient and multiplying the maximum torque that can be generated by the motor generator by the torque coefficient corresponding to the clutch, the torque coefficient corresponding to the accelerator, and the torque coefficient corresponding to the charging rate, The parallel hybrid electric vehicle control device according to claim 1, wherein the control device calculates the parallel hybrid electric vehicle. 3. The control apparatus for a parallel hybrid electric vehicle according to claim 2, wherein the accelerator-corresponding torque coefficient is set so as not to become 0 even when the accelerator is not operated. The control means calculates a vehicle request torque based on a depression state of the accelerator pedal, and when the vehicle request torque is insufficient with the electric motor torque, the engine torque is generated so that the engine torque corresponding to the shortage is generated. The control device for a parallel hybrid electric vehicle according to any one of claims 1 to 3, wherein the control device is controlled.

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