JP5706274B2 - Control device for hybrid vehicle - Google Patents

Description

  The present invention relates to a control device for a hybrid vehicle including an engine and a motor.

  2. Description of the Related Art Hybrid electric vehicles (also referred to as hybrid vehicles) equipped with motor generators (hereinafter also referred to as motors) in addition to engines have been put into practical use as travel drive sources for automobiles (hereinafter also referred to as vehicles). This hybrid electric vehicle is equipped with a battery, and the motor functions as a drive source of the vehicle when electric power is supplied from the battery, and functions as a drive source for the vehicle. It functions as a battery charger that converts power into electrical energy.

  As an example of such a hybrid electric vehicle, a clutch is provided between the engine and the transmission, and the motor is always connected to the input shaft of the transmission by providing a motor on the input shaft portion of the transmission. There is a configuration in which output rotation is transmitted to the input shaft of the transmission if connected. In this conventional hybrid electric vehicle, when the engine output is used or when the engine is started with a motor, the clutch is connected, and even when the engine output is used, when switching between the traveling range and the non-driving range, The clutch is disengaged, for example, when the gear position is switched when the travel range is selected.

  By the way, when the engine is idled with the clutch connected when the vehicle is stopped, the motor driving force and braking force are not required, so the motor has a positive (driving side) torque and a negative (braking side) torque. Control is performed so that zero torque is not generated. In this zero torque control, the motor generates a torque sufficient to cancel the friction torque generated with its rotation, and the output torque to the outside is zero.

  However, in the case of using a permanent magnet such as a permanent magnet type synchronous motor as a motor installed in a hybrid electric vehicle, even when zero torque control is performed by the motor so that neither positive torque nor negative torque is generated. During rotation, a minute torque is generated due to the characteristics of the motor, and the battery may be charged and discharged. For this reason, SOC balance control for maintaining the state of charge of the battery (hereinafter also referred to as SOC: State Of Charge) is performed.

This SOC balance control is performed by applying a positive or negative minute torque in the opposite direction to the torque generated by the characteristics of the motor to the motor. This positive or negative minute torque is generated by the motor itself by supplying power from the battery or charging the battery.
Patent Document 1 discloses a technique related to SOC balance control in a hybrid electric vehicle. In this technique, when the torque required for the motor is zero torque, the battery SOC is not overcharged or overdischarged in order to prevent a decrease in energy efficiency due to charging / discharging of the battery caused by rotation of the motor. Within the range, the SOC of the battery is maintained by generating a positive or negative minute torque in the motor.

JP 2007-216762 A

  By the way, an automatic transmission is applied to the hybrid electric vehicle described above, and a traveling range such as a D range (drive range) that normally selectively sets a plurality of shift stages, a P range (parking range), and an N range (neutral). When a non-traveling range such as a range is selected and operated, the clutch is connected / disconnected and the gear position is switched in accordance with the driving state of the vehicle.

In such a case, when a non-traveling range such as P range or N range is selected, the transmission is set in a state where torque of the engine and the motor is not transmitted to the driving wheel side, and the clutch is in a connected state and the engine is idled. Let it run.
In this case as well, when a motor using a permanent magnet is applied to a hybrid electric vehicle, the torque required for the motor interlocked with the engine when the clutch is connected and the non-traveling range is selected is zero torque. In order to generate a minute torque, SOC balance control is performed.

However, according to this SOC balance control, even when the non-traveling range is set, torque is generated in the motor, so that fuel consumption may be deteriorated.
In addition, it is effective to apply single motor driving to improve fuel efficiency and reduce noise at the time of starting. Is cut off once, and after setting the gear position of the transmission, the single running by the motor is carried out. For this reason, there is a possibility that the start timing of the vehicle may be delayed by the time for disconnecting the connected clutch, compared to the start of the vehicle not equipped with a motor but using only the engine as a drive source.

  The present invention has been conceived in view of such a problem, and an object of the present invention is to provide a control device for a hybrid vehicle that can suppress or eliminate deterioration of fuel consumption and can start the vehicle promptly. .

In order to achieve the above object, a control device for a hybrid vehicle of the present invention includes an engine, a motor that operates as an electric motor or a generator, a battery connected to the motor, and the engine and the motor. A traveling range having a clutch connected to connect and disconnect the output of the engine and an input shaft provided with the motor, and shifting the output rotation of at least one of the engine and the motor to transmit to the drive wheels And a non-traveling range that does not transmit the output rotation to the drive wheel, a transmission output shaft rotational speed detecting means for detecting the output shaft rotational speed of the transmission, and a connection / disconnection state of the clutch is switched. Clutch control means; motor control means for controlling the motor; shift control means for setting the travel range or the non-travel range of the transmission; And a battery charging state detecting means for detecting a charging state of luster, the state of charge of the battery detected by the battery state detecting means is within a large proper state (a predetermined tolerance than the predetermined charging rate, charging rate at a high state) than a predetermined charging rate, when the non-driving range is set in the transmission by the speed change control means, said clutch control means shuts off the clutch, further, the transmission output When the output shaft rotational speed of the transmission detected by the shaft rotational speed detecting means is smaller than a predetermined rotational speed, the motor control means performs zero rotational control for controlling the rotational speed of the motor to substantially zero rotational speed. It is characterized by doing.

When the non-traveling range of the transmission is set by the shift control means when the battery charge state detected by the battery charge state detection means is in the appropriate state, the clutch control means And when the output shaft rotational speed of the transmission detected by the transmission output shaft rotational speed detecting means is equal to or higher than a predetermined rotational speed, the motor control means outputs the output to the outside of the motor. It is preferable to implement zero torque control for controlling the torque to zero torque.

In addition, the state of charge control that performs the state of charge maintenance control which maintains the state of charge of the battery by connecting the clutch by the clutch control means, generating a positive or negative minute torque to the motor by the motor control means comprising means, when the state of charge of the battery detected by the battery state detection means not said appropriate conditions, the non-driving range is set in the transmission by the speed change control means, wherein the charge state maintained It is preferable to implement the state of charge maintenance control by a control means.

  (1) According to the control apparatus for a hybrid vehicle of the present invention, the shift control means controls the transmission in the transmission when the battery is in an appropriate state such as a state where the charge state is within a predetermined allowable range and the charge rate is greater than the predetermined charge rate. When the non-running range is set, the clutch control means disengages the clutch, so that the engine can maintain the idling speed or stop idling, and can suppress or eliminate the deterioration of fuel consumption. Further, since the clutch is not connected when the non-traveling range of the transmission is set, it is not necessary to disconnect the connected clutch when switching from the non-traveling range to the traveling range. For this reason, after switching from the non-traveling range to the traveling range, the gearing of the transmission can be performed immediately, and the vehicle can be started immediately. In addition, since the clutch is not connected when the non-traveling range of the transmission is set, it is possible to eliminate the occurrence of shock when the transmission is geared.

  Furthermore, when the output shaft speed of the transmission is smaller than the predetermined speed, the motor control means performs zero speed control, so that the motor speed is quickly converged to zero speed and charging / discharging due to motor rotation is performed. Generation can be quickly suppressed and prevented.

  (2) Further, when the non-traveling range is set in the transmission by the shift control means when the state of charge of the battery is appropriate, the clutch control means disconnects the clutch, and the output shaft rotational speed of the transmission is predetermined. If the motor control means is configured to perform zero torque control when the rotation speed is equal to or higher than the rotation speed, the motor rotation speed is set when the non-travel range of the transmission is set during traveling at a vehicle speed or higher corresponding to the predetermined rotation speed. And the output shaft rotational speed of the transmission can be suppressed from increasing, and the responsiveness when switching from the non-traveling range to the traveling range can be improved.

Further, in order to perform the zero torque control of the motor, electric power is required as the rotational speed of the motor increases. However, if the motor control means is configured to perform the zero torque control in an appropriate state, Responsiveness such as gearing at the time of switching the setting from the non-traveling range to the traveling range can be improved while the charging state is converged to a predetermined allowable range .

(3) The charging state maintaining control means for connecting the clutch by the clutch controlling means, generating a positive or negative minute torque to the motor by the motor controlling means, and performing the charging state maintaining control for maintaining the charging state of the battery. For example, when the charging state of the battery is within a predetermined allowable range and lower than the predetermined charging rate and is not in an appropriate state, the charging state maintaining control is performed by the charging state maintaining control means. Then, the state of charge of the battery can be maintained within a predetermined allowable range .

It is a mimetic diagram showing composition of a control device of a hybrid vehicle concerning one embodiment of the present invention. It is a time chart which shows the motor instruction | indication torque and SOC of a battery in the hybrid vehicle to which the control apparatus concerning one Embodiment of this invention is applied, (a) shows a motor instruction | indication torque, (b) is the charge condition ((b) of a battery) SOC). It is a flowchart which shows the control by the control apparatus of the hybrid vehicle concerning one Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<One Embodiment>
[Constitution]
First, a configuration of a hybrid electric vehicle (hybrid vehicle, also simply referred to as a vehicle) to which a control device according to an embodiment is applied will be described. The hybrid vehicle according to the present embodiment is a so-called large or medium-sized hybrid electric vehicle such as a truck or a bus.

  As shown in FIG. 1, the hybrid vehicle of this embodiment includes an engine (internal combustion engine) 1 as a vehicle drive source, a clutch 2 that connects and disconnects the output of the engine 1, and an electric motor or power generator as a vehicle drive source. A motor (motor generator) 3 that operates as a machine, a transmission 4 that shifts and transmits the output rotation of at least one of the engine 1 and the motor 3 that are driving sources of the vehicle, drive wheels 9, and these transmissions 4 and a drive wheel 9 are provided, and a power transmission member 5 that transmits rotational power is provided.

An output shaft (crankshaft) 1 </ b> A that outputs rotational torque of the engine 1 is connected to an input shaft of the clutch 2.
The clutch 2 connects and disconnects the output of the engine 1. The clutch 2 is a hydraulic (hydraulic pressure) clutch provided with an actuator 6, and can be switched between a connected state and a disconnected state by the operation of the actuator 6. When the clutch 2 is connected, the output of the engine 1 is transmitted, and when the clutch 2 is disconnected, the output of the engine 1 is not transmitted.

  Although not shown in detail, the actuator 6 includes, for example, a hydraulic chamber, a piston adjacent to the hydraulic chamber, and a return spring that returns the piston to a predetermined position. When hydraulic pressure (clutch pressure) is supplied to the hydraulic chamber, the piston moves against the return spring in response to this, and presses the clutch plates on the input side and output side of the clutch 2. At this time, as the clutch pressure increases, the clutch plates on the input side and output side of the clutch 2 approach each other and engage. On the other hand, when the clutch pressure decreases, the piston is returned by the return spring, and the clutch plates on the input side and output side of the clutch 2 are not pressed and are separated.

  The motor 3 functions as a drive source for the vehicle if it operates as an electric motor. Moreover, if the motor 3 operates as a generator, it functions as a power generator that recovers regenerative energy due to output rotation of the engine 1 or braking of the vehicle. The rotor (rotor) of the motor 3 is fixed to the output shaft of the clutch 2, that is, the input shaft 4 </ b> A of the transmission 4. Here, a permanent magnet type synchronous motor using a permanent magnet is used as the motor 3.

  Further, the motor 3 is connected to the battery 10 via the inverter 20 by a power supply line. Accordingly, the battery 3 can be fed to the motor 3 to operate the motor 3 as an electric motor, and the motor 3 can be operated as a generator to charge the battery 10 with the electric power generated by the motor 3. This charging / discharging is performed by switching the operating state of the inverter 20.

The battery 10 is connected to a battery ECU (battery state detection means) 11 via a control signal line, and the state of charge (hereinafter also referred to as SOC) is managed by the battery ECU 11.
The inverter 20 is connected to the vehicle ECU 50 via the inverter ECU 21 via a control signal line, and the operation of the inverter 20 is controlled by the vehicle ECU 50 via the inverter ECU 21.

Further, a motor rotation speed sensor 31 for detecting the rotation speed of the input shaft 4A, that is, the rotation speed (motor rotation speed) _NMTR of the motor 3 is provided near the input shaft 4A of the transmission 4. The motor rotation speed sensor 31 is connected to the vehicle ECU 50, and information (detection signal) of the motor rotation speed N _MTR detected by the motor rotation speed sensor 31 is transmitted to the vehicle ECU 50.
The transmission 4 shifts the output rotation of either or both of the engine 1 and the motor 3 input to the input shaft 4A and outputs it to the output shaft 4B. Each engaging element such as a sleeve and a clutch gear for engaging or releasing the gear pair of the stage is included. The transmission 4 has a travel range set when a required engagement element is engaged, and a non-travel range when any of the engagement elements is released (not engaged).

The input shaft 4 </ b> A of the transmission 4 is equipped with the rotor of the motor 3, and the power transmission member 5 is connected to the output shaft 4 </ b> B of the transmission 4.
When the engaging element of the transmission 4 is engaged, the gear pair corresponding to the engaging element to be engaged is engaged, and the corresponding gear stage is set. When the gear stage is set, the transmission 4 changes the output rotation of either or both of the engine 1 and the motor 3 input to the input shaft 4A at a gear ratio according to the set gear stage, and outputs the output shaft 4B. Output to. It should be noted that the gear stage that is set when the output rotation of at least one of the engine 1 and the motor 3 is used for traveling is set in the traveling range.

  Further, when the engagement element of the transmission 4 is released, no gear stage is set. In a state where this gear stage is not set, the transmission 4 does not transmit any output rotation of the engine 1 and the motor 3 input to the input shaft 4A to the output shaft 4B. In this case, the transmission 4 has an N range (neutral range) in which the rotation of the output shaft 4B of the transmission 4 is not restricted, or a P range (parking range) in which the rotation of the output shaft 4B of the transmission 4 is restricted. The N range and the P range are set in a non-traveling range in which the output rotations of the engine 1 and the motor 3 are not used for traveling. When the N range is set in the transmission 4, the power transmission between the input shaft 4A and the output shaft 4B is interrupted, and the rotation of the output shaft 4B and the power transmission member 5 is not restricted. Further, when the P range is set in the transmission 4, the input shaft 4A and the output shaft 4B are cut off from the power transmission, and the rotation of the output shaft 4B and the power transmission member 5 is restricted.

Such engagement or disengagement of each engagement element of the transmission 4 is performed using hydraulic pressure by a gear shift unit (not shown), and the gear shift unit is controlled by the vehicle ECU 50.
A transmission output shaft rotational speed sensor 32 for detecting the rotational speed (output shaft rotational speed) _{NT / M} of the output shaft 4B is attached in the vicinity of the output shaft 4B of the transmission 4. The transmission output shaft rotational speed sensor 32 is connected to the vehicle ECU 50, and information (detection signal) of the output shaft rotational speed _{NT / M} detected by the transmission output shaft rotational speed sensor 32 is transmitted to the vehicle ECU 50. The

The power transmission member 5 includes a propeller shaft, a differential device, a drive shaft, and the like. The power transmission member 5 is interposed between the output shaft 4B of the transmission 4 and the drive wheels 9, and between the transmission 4 and the drive wheels 9. Power transmission is performed in both directions.
The vehicle is equipped with a shift unit (shift lever) 30 operated by the driver. The shift unit 30 is provided with a plurality of ranges, and is configured such that any one of the ranges can be selected by switching the shift position by the driver. Examples of the plurality of ranges include a range such as a P range (parking range), an R range (reverse range), an N range (neutral range), and a D range (drive range). Among these, the P range and N range are included in the non-traveling range, and the R range and D range are included in the traveling range.

In addition, although what shows P range, R range, N range, and D range is set to the shift part 30 here, not only this but driving ranges, such as L range, may be further provided. Moreover, the specific number of ranges set as a running range and a non-running range is not limited to this.
The shift unit 30 is connected to the vehicle ECU 50, and information on the range selected in the shift unit 30 is transmitted to the vehicle ECU 50.

Next, the configuration of the control system according to the hybrid vehicle control device will be described.
The engine 1, clutch 2, motor 3, transmission 4, battery 10 and inverter 20 are controlled or managed by electronic control using a computer. The battery ECU 11 for managing the battery 10 and the inverter 20 are controlled. And an inverter ECU 21 for controlling the operation of each.

A vehicle ECU 50 that controls the battery ECU 11, the inverter ECU 21, the engine 1, the clutch 2, the motor 3, and the transmission 4 is provided. Each of these ECUs 11, 21 and 50 is an electronic control device including, for example, a microprocessor, a ROM, a RAM, an input / output circuit, and the like.
The battery ECU 11 acquires information such as the temperature of the battery 10, the current to be charged / discharged, and the voltage, and calculates and detects the state of charge (SOC) of the battery 10 based on these information. This SOC can be represented by the charge rate calculated based on the charge rate of the battery 10 or this charge rate. The SOC of the battery 10 detected by the battery ECU 11 is transmitted to the vehicle ECU 50.

The vehicle ECU 50 includes a clutch control unit (clutch control unit) 51 that controls the operation of the clutch 2, a motor control unit (motor control unit) 52 that controls the operation of the motor 3, and a shift control unit (a control unit that controls the transmission 4). (Shift control means) 53 and an SOC balance control unit (charge state maintaining means) 54 for maintaining the charged state of the battery 10.
The clutch control unit 51 switches the connection / disconnection state of the clutch 2 by controlling the clutch pressure of the actuator 6 attached to the clutch 2 according to the driving state of the vehicle.

The motor control unit 52 controls the operation of the motor 3 according to the driving situation of the vehicle. That is, the motor control unit 52 controls the power supply from the battery 10 to the motor 3 and the charging from the motor 3 to the battery 10 by controlling the operation of the inverter 20 via the inverter ECU 21.
Further, the motor control unit 52 performs zero torque control for controlling the output torque of the motor 3 to zero torque and zero rotation control for controlling the rotation speed of the motor 3 to zero rotation.

Zero torque control is to generate a torque in the motor 3 that cancels the drag torque of the motor 3 itself, and to prevent the torque from being output to the outside of the motor 3. For example, if zero torque control is performed while the motor 3 is rotating, the motor 3 rotates at the motor rotation speed N _MTR corresponding to the torque applied to the motor 3 from the outside, and torque must be applied to the motor 3 from the outside. For example, the motor 3 maintains the motor rotation speed N _MTR . In addition, since the drag torque of the motor 3 itself increases as the rotation speed of the motor 3 increases, electric power corresponding to the rotation speed of the motor 3 is required to perform zero torque control.

The zero rotation control, based on the motor rotational speed N _MTR detected by motor speed sensor 31, the motor rotational speed N _MTR is reverse with respect to the torque applied to the motor 3 from the outside so as to approach zero rotation ( The motor 3 is caused to generate torque in a direction in which the rotation of the motor 3 is stopped.
The shift control unit 53 controls the engagement and release of each engagement element of the transmission 4 according to the driving situation of the vehicle. As a result, the shift control unit 53 switches the transmission 4 between the travel range setting state and the non-travel range setting state.

  When the non-traveling range is selected by the operation of the shift unit 30 by the driver, the shift control unit 53 is not in the control to be performed with the clutch 2 such as SOC balance control (charge state maintenance control) described later being connected. As long as the engagement element of the transmission 4 is released, the non-traveling range is set. Further, when the driving range is selected by the driver operating the shift unit 30, a required engagement element is engaged except when the shift stage is switched, and the shift stage according to the driving state of the vehicle is set. .

  The SOC balance control unit 54 performs control to maintain (balance) the SOC of the battery 10 by connecting the clutch 2 by the clutch control unit 51 and generating positive or negative minute torque in the motor by the motor control unit 52. . Hereinafter, this SOC balance control will be described with reference to FIG. Here, the motor 3 is a motor that generates a slight positive torque when discharged due to its characteristics, and discharges the battery 10.

  In FIG. 2A, the torque on the drive side of the vehicle is positive on the vertical axis, and the instruction torque to the motor 3 by the motor control unit 52 is defined. FIG. 2B defines the SOC of the battery 10 on the vertical axis. The time axis is defined on the horizontal axis of FIGS. 2 (a) and 2 (b). While the SOC balance control shown in FIG. 2 is being carried out, the clutch 2 is always connected by the clutch control unit 51, and the instruction torque of the motor 3 repeats the zero torque phase and the negative torque phase.

At time t ₀ , _zero torque control by the motor control unit 52 is started. The SOC _s at the start of control is stored in the vehicle ECU 50.
From time t ₀ to time t _1, which is implemented the zero torque control by the motor controller 52, the torque instructions to the motor 3, as shown in FIG. 2 (a) is a zero torque. On the other hand, as shown in FIG. 2B, the SOC of the battery 10 decreases from the time point t ₀ toward the time point t ₁ . That is, the actual motor 3 generates a small positive torque, and the battery 10 is discharged. At this time, the vehicle ECU 50 periodically calculates the difference between the SOC of the battery 10 detected by the battery ECU 11 and the SOC _s at the start of control.

At time t ₁ , the SOC of the battery 10 becomes SOC _L smaller by the first predetermined minute rate than the SOC _s at the control start time. The SOC _L of the battery 10 is stored in the vehicle ECU 50. This first predetermined minute rate does not cause excessive hunting under the execution of the SOC balance control, and a charge rate such as 1% is set experimentally and empirically in advance as the SOC difference in consideration of the SOC detection accuracy. Is done. Further, in the time t _1, the charging of the battery 10 is started. This charging is repeatedly started on condition that the SOC of the battery 10 becomes SOC _L.

From time t ₁ to time t ₃ , the battery 10 is charged, and the SOC balance control unit 54 causes the motor control unit 52 to generate a minute negative torque. As a result, as shown in FIG. 2B, the SOC of the battery 10 increases from time t ₁ to time t ₃ . At this time, the vehicle ECU 50 periodically calculates the difference between the SOC of the battery 10 detected from the battery ECU 11 and the SOC _L at time t ₁ .

In the period from time t ₁ to time t ₂ , a ramp process is performed to suppress the command output torque of the motor 3 by the motor control unit 52 to a predetermined change rate (decrease rate).
At the time point t ₃ , the SOC of the battery 10 becomes SOC _H larger than the SOC _L at the time point t _{1 by} a second predetermined minute rate. This second predetermined minute rate does not cause excessive hunting in the execution of the SOC balance control, and a charge rate of 2%, for example, is set in advance experimentally and empirically as a difference in SOC in consideration of the SOC detection accuracy. The At this time t ₃ , the instruction to charge the battery 10 is completed. Then, zero torque control by the motor control unit 52 is started. In other words, charging of battery 10 is instructed to be terminated on condition that the SOC of battery 10 becomes SOC _H.

During the period from time t ₃ to time t ₄ , a ramp process is performed to suppress the command output torque of the motor 3 by the motor control unit 52 to a predetermined rate of change (increase rate). For this reason, the SOC of the battery 10 slightly increases during this period after the end of the charging control of the battery 10.
From time t ₄ to time t _5, it is implemented zero torque control by the motor control unit 52 again. Even during this period, the actual motor 3 generates a small positive torque, and the battery 10 is discharged. At this time, the vehicle ECU 50 compares the SOC of the battery 10 detected by the battery ECU 11 with the stored SOC _L at the time t ₁ .

The time point t ₅ is the same as the time point t ₁ , and the time points t _{6 to} t ₈ are the same as the time points t _{2 to} t ₄ .
The vehicle ECU 50 performs various controls based on the SOC of the battery 10 detected by the battery ECU 11, using these control units 51, 52, 53, 54. Such various controls will be described below.
The vehicle ECU 50 performs forced charging and forced discharging so that the SOC of the battery 10 detected by the battery ECU 11 falls within a predetermined allowable range. When the SOC of the battery 10 falls below the lower limit of the predetermined allowable range, the vehicle ECU 50 operates the motor 3 as a generator to perform forced charging. When the SOC of the battery 10 exceeds the upper limit of the predetermined allowable range, the vehicle ECU 50 Operates as an electric motor and performs forced discharge.

Note that the predetermined allowable range is a range of the charging rate such that the SOC of the battery 10 is 30% or more and 70% or less, for example, as the SOC range in which there is little risk of deterioration of the battery 10 unless forced charging or discharging is performed. , Set in advance experimentally and empirically.
The vehicle ECU 50 performs the following control when the SOC of the battery 10 is within a predetermined allowable range.

If the SOC of battery 10 is within a predetermined allowable range and greater than the first predetermined charging rate SOC ₁ (appropriate state), vehicle ECU 50 determines that transmission 4 is set to the N range (non-traveling range). Then, the clutch control unit 51 closes the clutch 2. In this case, the vehicle ECU 50 controls the motor control unit 52 based on the output shaft rotational speed _{NT / M} detected by the transmission output shaft rotational speed sensor 32.

The first predetermined charging rate SOC ₁ is set lower than the upper limit of the predetermined allowable range, and the SOC of the battery 10 is kept within the predetermined allowable range even if the motor controller 52 performs zero torque control of the motor 3 during vehicle travel. As the SOC that can be converged at, a charging rate such that the SOC of the battery 10 is 40% is set experimentally and empirically in advance.
SOC of the battery 10 is a proper state, when the clutch 2 is disconnected, the output shaft rotational speed N _{T / M,} which is detected by the transmission output shaft rotational speed sensor 32 is smaller than a predetermined rotational speed N ₁ For example, the vehicle ECU 50 performs zero rotation control by the motor control unit 52. In this case, since the motor rotational speed N _MTR detected by the motor rotational speed detecting sensor 31 in the case of substantially zero rotation is not required to implement the zero rotation control by the motor control unit 52, the vehicle ECU50 includes a motor Zero torque control is performed by the control unit 52.

The motor rotation speed _NMTR being substantially zero rotation means a rotation speed at which charging / discharging of the battery 10 due to the minute torque generated due to its characteristics can be ignored even when the motor 3 is rotated. Is set automatically.
The predetermined rotational speed N ₁ is set as an upper limit of the rotational speed difference between the input shaft 4A and the output shaft 4B of the transmission 4 that does not cause a shock when gears are engaged in the transmission 4, for example, traveling by creep torque The rotational speed corresponding to the vehicle speed obtained by adding a predetermined margin to the medium low vehicle speed is set experimentally and empirically in advance.

Further, when the SOC of the battery 10 is in an appropriate state and the clutch 2 is disengaged, the output shaft rotational speed _{NT / M} detected by the transmission output shaft rotational speed sensor 32 is equal to or higher than the predetermined rotational speed N _1. If so, the vehicle ECU 50 performs zero torque control by the motor control unit 52.
Next, if the SOC of the battery 10 is in a predetermined allowable range and smaller than the first predetermined charging rate SOC ₁ , the vehicle ECU 50 sets the transmission 4 to the P range or the N range (non-traveling range). In this case, the SOC balance control by the SOC balance control unit 54 described above is performed.

[Action / Effect]
Since the control apparatus for a hybrid vehicle according to an embodiment of the present invention is configured as described above, a control flow as shown in FIG. 3 is performed by the vehicle ECU 50. This control flow process is periodically performed when the key switch of the vehicle is set to ON.
In step S10, it is determined whether or not the transmission 4 is set to a non-traveling range such as a P range or an N range. If it is set to the non-traveling range, the process proceeds to step S20, and if it is set to the traveling range such as the D range, the current control flow is ended (returned).

In step S20, it determines whether the SOC of the battery 10 detected by the battery ECU11 is greater than a first predetermined charging rate SOC _1. Is larger than SOC first predetermined charging rate SOC ₁ of battery 10 proceeds to step S30, SOC of the battery 10 shifts to step S100 if the first predetermined charging rate SOC ₁ or less.
In step S30, it is determined whether or not the flag F is set to 1. This flag F is set to 1 if the clutch 2 is engaged, and is set to 0 if the clutch 2 is disengaged. If the flag F is 1, the process proceeds to step S40, and if the flag F is 0, the process proceeds to step S32.

In step S <b> 32, the clutch 2 is disconnected by the clutch control unit 51. Then, control goes to a step S34.
In step S34, the flag F is set to 1, and the process proceeds to step S40.
In step S40, it is determined whether or not the non-traveling range set for the transmission 4 is the N range. If the N range is set for the transmission 4, the process proceeds to step S50, and if the P range is set for the transmission 4, the process proceeds to step S70.

At step S50, it is determined whether or not the output shaft rotational speed N _{T / M,} which is detected by the transmission output shaft rotational speed sensor 32 is greater than the predetermined rotational speed N _1. Output shaft rotational speed N _{T / M} is shifted to be step S60 is greater than a predetermined rotational speed N _1, the output shaft rotational speed N _{T / M} transitions to step S70 if the predetermined rotational speed N ₁ or less.
In step S60, zero torque by the motor control 52 is performed.

In step S70, it is determined whether or not the motor rotational speed N _MTR is substantially zero. If the motor speed N _MTR is substantially zero, the process proceeds to step S80, and if the motor speed N _MTR is not substantially zero, the process proceeds to step S90.
In step S80, zero torque control is performed by the motor control unit 52. Then, the current control flow ends (returns).

In step S90, zero rotation control by the motor control unit 52 is performed. Then, the current control flow ends (returns).
In step S100, the clutch control unit 51 connects the clutch 2, and the process proceeds to step S110.
In step S110, the flag F is set to 0, and the process proceeds to step S120.

In step S120, SOC balance control by the SOC balance control unit 54 is performed. Then, the current control flow ends (returns).
In step S80 of this control flow, the motor rotation speed N _MTR is substantially zero rotation, and functions as a step for preventing hunting of zero rotation control. For this reason, if the control setting of the zero rotation control is appropriately set so as not to cause hunting, step S80 can be appropriately omitted.

Therefore, the N range (non-running range) is set in the transmission 4 by the shift control unit 53 when the SOC of the battery 10 is in a predetermined allowable range and larger than the first predetermined charging rate SOC _1. Since the clutch control unit 52 disengages the clutch 2, the engine 1 can maintain the idling speed or stop idling, and can suppress or eliminate the deterioration of fuel consumption. Further, since the clutch 2 is not connected when the N range of the transmission 4 is set, it is not necessary to disconnect the connected clutch 2 when switching from the N range to the travel range such as the D range. For this reason, after switching from the N range to the D range, the gearing of the transmission 4 can be performed immediately and the vehicle can be started immediately. Moreover, since the clutch 2 is not connected when the N range of the transmission 4 is set, it is possible to eliminate the occurrence of shock when the transmission 4 is geared.

Further, when the output shaft rotational speed _{NT / M of} the transmission 4 is smaller than the predetermined rotational speed N ₁ , the motor control unit 52 performs the zero rotational control. It can be made to converge and the generation | occurrence | production of charging / discharging by rotation of the motor 3 can be suppressed rapidly and can be prevented.
Further, when the N range is set in the transmission 4 by the transmission control unit 53 when the SOC of the battery 10 is in an appropriate state, the clutch control unit 51 disengages the clutch 2 and further the output shaft rotational speed N of the transmission 4. _{When T / M} is equal to or higher than the predetermined rotational speed N ₁ , the motor control unit 52 performs zero torque control. Therefore, the N range setting of the transmission 4 is performed during traveling at a vehicle speed or higher corresponding to the predetermined rotational speed N _1. Occasionally, the speed difference between the motor speed N _MTR and the output shaft speed _{NT / M} of the transmission 4 is prevented from increasing, and the response when switching from the N range to the D range is improved. Can be made.

Further, in order to perform the zero torque control of the motor 3, electric power is required as the rotation speed of the motor 3 increases. However, when the SOC of the battery 3 is in an appropriate state, the motor control unit 52 performs the zero torque control. Therefore, while converging to a constant allowable range where the state of charge of the battery 10, it is possible to improve the responsiveness of gear engagement or the like at the time of switching the setting from the N range to the D range.

Further, when a non-traveling range of P range or N range is set in the transmission 4, the clutch control unit 51 connects the clutch 2, and the motor control unit 52 causes the motor 3 to generate positive or negative minute torque. An SOC balance control unit 54 that performs SOC balance control for maintaining the SOC of the battery 10, and the SOC of the battery 10 is within a predetermined allowable range when the charge rate of the battery 10 is less than or equal to the first predetermined charge rate SOC ₁ . And when it is not an appropriate state, since SOC balance control is implemented by the SOC balance control part 54, SOC of the battery 10 can be maintained in a predetermined permissible range .

[Others]
Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.
In the above-described embodiment, a vehicle equipped with a single clutch is shown. However, the present invention is not limited to this, and the control device of the present invention is applied to a vehicle equipped with a so-called DCT (Dual Clutch Transmission) equipped with two clutches. May be.

In addition, the first predetermined minute rate is set to 1% and the second predetermined minute rate is set to 2%. However, the present invention is not limited to this. An appropriate setting value such as% can be used.
Further, although the first predetermined charging rate is set to 40%, an appropriate setting value such as 45% or 65% can be used for the first predetermined charging rate.

  The hybrid vehicle control device of the present invention can be applied not only to automobiles such as trucks and buses but also to small vehicles such as passenger cars.

DESCRIPTION OF SYMBOLS 1 Engine 1A Output shaft 2 Clutch 3 Motor 4 Transmission 4A Input shaft 4B Output shaft 5 Power transmission member 6 Actuator 9 Drive wheel 10 Battery 11 Battery ECU (Battery charge state detection means)
20 Inverter 21 Inverter ECU
30 shift unit 31 motor rotation speed sensor 32 transmission output shaft rotation speed sensor (transmission output shaft rotation speed detection means)
50 Vehicle ECU
51 Clutch control unit (clutch control means)
52 Motor control unit (motor control means)
53 Shift control section (shift control means)
54 SOC balance control unit (charge state maintenance control means)

Claims (3)

An engine,
A motor that operates as an electric motor or generator;
A battery connected to the motor;
A clutch that is interposed between the engine and the motor and connects and disconnects transmission of the output of the engine;
A travel range that includes an input shaft provided with the motor, shifts the output rotation of at least one of the engine and the motor and transmits the output rotation to the drive wheel, and a non-travel range that does not transmit the output rotation to the drive wheel; A transmission having
A transmission output shaft rotational speed detection means for detecting an output shaft rotational speed of the transmission;
Clutch control means for switching the connection / disconnection state of the clutch;
Motor control means for controlling the motor;
Shift control means for setting the travel range or the non-travel range of the transmission;
Battery charge state detection means for detecting the charge state of the battery,
Wherein the battery state detecting means at a proper state charge state is greater than the predetermined charging rate of the battery detected by, when the non-driving range in the transmission by the speed change control means is set, the clutch control The means disengages the clutch, and further, when the output shaft rotational speed of the transmission detected by the transmission output shaft rotational speed detection means is smaller than a predetermined rotational speed, the motor control means A control apparatus for a hybrid vehicle, which performs zero rotation control for controlling a rotation speed to substantially zero rotation. When the non-traveling range of the transmission is set by the shift control means when the state of charge of the battery detected by the battery charge state detection means is in the proper state, the clutch control means disconnects the clutch. Further, when the output shaft rotational speed of the transmission detected by the transmission output shaft rotational speed detecting means is equal to or greater than a predetermined rotational speed, the motor control means outputs an output torque to the outside of the motor. The hybrid vehicle control device according to claim 1, wherein zero torque control is performed to control to zero torque. Charge state maintenance control means for performing charge state maintenance control for connecting the clutch by the clutch control means, generating positive or negative minute torque to the motor by the motor control means, and maintaining the charge state of the battery. Prepared,
The charge state of the battery detected by the battery state detection means is not the proper state, the when the non-driving range in the transmission by speed change control means is set, the by the charge state maintenance control means The control device for a hybrid vehicle according to claim 1 or 2, wherein the control for maintaining the state of charge is performed.

Images