JP2005163595A - Engine torque control device for hybrid vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an engine torque control device for an hybrid vehicle having no problem such as error in battery power calculation value caused by error of rotation inertia and capable of securing stable travel while keeping the battery actual performance power within an allowable range. <P>SOLUTION: A hybrid vehicle (series, parallel hybrid in general) using motor generators MG1, MG2 driven by a drive device such as a battery 4 and an inverter 3 as a part of power source for vehicle drive, is provided with an engine torque command value correction means increasing engine torque command value Te ref according to an exceeding amount when the battery actual performance power discharges power exceeding a battery charge/discharge power allowable range determined by a battery condition, and decreasing engine torque command value Te ref according to exceeding amount when battery is charged exceeding the battery charge/discharge power allowable range . <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an engine torque control device for a hybrid vehicle using an engine as a power source and using a motor driven by a drive device such as a battery and an inverter as a part of a power source for driving a vehicle.

  Conventionally, protection against a failure due to overpower of the power storage means includes an overcurrent breaker and a fuse installed in series with the battery circuit. This is an irreversible disconnection when a predetermined current is exceeded, and the operation of the battery is stopped. This causes inconveniences such as insufficient driving torque of the vehicle, and it takes time to restart the operation.

As a similar overload protection application example, a motor drive inverter control device using a motor overload protection method based on drooping characteristics (drooping) is known (see Patent Document 1).
JP-A-6-38586

  However, the battery protection technology using the former fuse breaker has a problem that the operation of the battery is temporarily stopped as a result of protection, although the younger brother protection function is provided.

  Further, the latter conventional device is a motor protection and a protection by torque current detection, and therefore cannot be directly applied to the purpose of battery protection of a hybrid vehicle. Furthermore, although the conventional apparatus is applied to speed control, in a hybrid vehicle, since it is generally not speed control but torque control, the speed command cannot have a drooping characteristic as well.

  The present invention has been made paying attention to the above-mentioned problem, and there is no problem such as an error in the battery power calculation value due to an error in the rotational inertia, and a stable running is ensured while keeping the actual battery power within an allowable range. An object of the present invention is to provide an engine torque control device for a hybrid vehicle.

In order to achieve the above object, in the present invention, a hybrid vehicle using a motor driven by a driving device such as a battery and an inverter as a part of the power source for driving the vehicle (series Parallel hybrid in general)
Battery actual power detecting means for detecting the actual power of the battery, and when the battery actual power is discharged exceeding the allowable battery charge / discharge power range determined from the battery state, depending on the excess Engine torque command value correction means for decreasing the engine torque command value in accordance with the excess when the engine torque command value is increased and charging exceeds the battery charge / discharge power allowable range. .

  Therefore, in the engine torque control device for a hybrid vehicle according to the present invention, the engine torque command value correction means uses the battery charge / discharge power allowable range based on the actual battery power instead of the calculated battery power. The engine torque command value is adjusted according to the amount of deviation. As a result, the battery actual power is closed-loop controlled within the allowable range, so that stable traveling can be ensured while the battery actual power is maintained within the allowable range. Since the actual battery power is an actual value including an increase or decrease in the kinetic energy of the rotating element, there is no problem of an error in the actual battery power calculation value due to an error in rotational inertia.

  Hereinafter, the best mode for realizing an engine torque control device for a hybrid vehicle according to the present invention will be described based on a first embodiment shown in the drawings.

First, the configuration will be described.
[Hybrid power engine]
FIG. 1 is an overall system diagram of a drive system of a hybrid vehicle to which the engine torque control device of the first embodiment is applied. As shown in FIG. 1, the hybrid power engine has an engine E, a first motor generator MG1, and a second motor generator MG2 as power sources, and these power sources E, MG1, MG2 and output shafts The planetary gear transmission (two-degree-of-freedom differential gear transmission mechanism) connected to OUT includes a first planetary gear PG1, a second planetary gear PG2, a third planetary gear PG3, an engine clutch EC, It has a brake LB, a high clutch HC, and a high / low brake HLB.

  A multilayer motor in which a stator S, an inner rotor IR, and an outer rotor OR are arranged on the same axis is applied to the first motor generator MG1 and the second motor generator MG2. This multi-layer motor controls the inner rotor IR and the outer rotor OR independently by applying a composite current (for example, a combined current of three-phase alternating current and six-phase alternating current) to the stator coil of the stator S. The stator S and the outer rotor OR constitute a first motor generator MG1, and the stator S and the inner rotor IR constitute a second motor generator MG2.

  The first planetary gear PG1, the second planetary gear PG2, and the third planetary gear PG3 that constitute the planetary gear transmission are all single pinion type planetary gears. The first planetary gear PG1 includes a first sun gear S1, a first pinion carrier PC1 that supports the first pinion P1, and a first ring gear R1 that meshes with the first pinion P1. The second planetary gear PG2 includes a second sun gear S2, a second pinion carrier PC2 that supports the second pinion P2, and a second ring gear R2 that meshes with the second pinion P2. The third planetary gear PG3 includes a third sun gear S3, a third pinion carrier PC3 that supports the third pinion P3, and a third ring gear R3 that meshes with the third pinion P3.

  The first sun gear S1 and the second sun gear S2 are directly connected by a first rotating member M1, and the first ring gear R1 and the third sun gear S3 are directly connected by a second rotating member M2, and the second pinion carrier PC2 And the third ring gear R3 are directly connected by a third rotating member M3. Accordingly, the three planetary gears PG1, PG2, and PG3 include the first rotating member M1, the second rotating member M2, the third rotating member M3, the first pinion carrier PC1, the second ring gear R2, and the third pinion carrier PC3. 6 rotation elements.

  A connection relationship among the power sources E, MG1, MG2, the output shaft OUT, the engine clutch EC, and the engagement elements LB, HC, HLB for the six rotating elements of the planetary gear transmission will be described. The second rotating member M2 is in a free state that is not connected to any of these, and the remaining five rotating elements are connected as follows.

  The engine output shaft of the engine E is connected to the third rotating member M3 via the engine clutch EC. That is, when the engine clutch EC is engaged, the second pinion carrier PC2 and the third ring gear R3 are set to the engine speed via the third rotation member M3.

  The first motor generator output shaft of the first motor generator MG1 is directly connected to the second ring gear R2. Further, a high / low brake HLB is interposed between the first motor generator output shaft and the transmission case TC. That is, when releasing the high / low brake HLB, the second ring gear R2 is set to the rotation speed of the first motor generator MG1. When the high / low brake HLB is engaged, the rotation of the second ring gear R2 and the first motor generator MG1 is stopped.

  The second motor generator output shaft of the second motor generator MG2 is directly connected to the first rotating member M1. Further, a high clutch HC is interposed between the second motor generator output shaft and the first pinion carrier PC1, and a low brake LB is interposed between the first pinion carrier PC1 and the transmission case TC. Is done. That is, when only the low brake LB is engaged, the first pinion carrier PC1 is stopped, and when only the high clutch HC is engaged, the first sun gear S1, the second sun gear S2, and the first pinion carrier PC1 are connected to the second motor generator MG2. Set the rotation speed. Further, when the low brake LB and the high clutch HC are engaged, the first sun gear S1, the second sun gear S2, and the first pinion carrier PC1 are stopped.

  The output shaft OUT is directly connected to the third pinion carrier PC3. A driving force is transmitted from the output shaft OUT to the left and right driving wheels via a propeller shaft, a differential, and a drive shaft (not shown).

  As a result, as shown in FIGS. 4 and 5, the first motor generator MG1 (R2), the engine E (PC2, R3), the output shaft OUT (PC3), the second motor generator MG2 (S1) , S2), and a rigid lever model that can simply represent the dynamic behavior of the planetary gear train can be introduced.

  Here, the “collinear diagram” is a velocity diagram used in a simple and easy-to-understand method of drawing instead of the method of obtaining by equation when considering the gear ratio of the differential gear. Take the number of rotations (rotational speed) of the rotating elements, take each rotating element such as ring gear, carrier, sun gear, etc. on the horizontal axis, and align the intervals of each rotating element based on the gear ratio of sun gear and ring gear The lever ratios (α, β, δ) are arranged. Incidentally, (1) shown in FIGS. 4 (a) and 5 (a) is a collinear diagram of the first planetary gear PG1, (2) is a collinear diagram of the second planetary gear PG2, (3) Is a collinear diagram of the third planetary gear PG3.

  The engine clutch EC is a multi-plate friction clutch that is engaged by hydraulic pressure, and is disposed at a position that coincides with the rotational speed axis of the engine E on the alignment charts of FIGS. 4 and 5. The rotation and torque are input to a third rotating member M3 that is an engine input rotating element of the planetary gear transmission.

  The low brake LB is a multi-plate friction brake that is fastened by hydraulic pressure, and is disposed at a position outside the rotational speed axis of the second motor generator MG2 on the alignment chart of FIGS. As shown in (a), (b) of FIG. 5 and (a), (b) of FIG. 5, a low-side gear ratio mode for sharing the low-side gear ratio is realized, and the gear ratio is fixed to the low gear ratio.

  The high clutch HC is a multi-plate friction clutch that is engaged by hydraulic pressure, and is disposed at a position that coincides with the rotational speed axis of the second motor generator MG2 on the alignment charts of FIGS. 4 (d), (e) and (d), (e) of FIG. 5 realize the high side gear ratio mode for sharing the high side gear ratio.

  The high / low brake HLB is a multi-plate friction brake that is fastened by hydraulic pressure, and is arranged at a position that coincides with the rotational speed axis of the first motor generator MG1 on the collinear charts of FIGS. The gear ratio is fixed to the low gear ratio on the underdrive side by fastening together with the high gear ratio, and the gear ratio is fixed to the high gear ratio on the overdrive side by fastening with the high clutch HC.

[Control system for hybrid power engine]
As shown in FIG. 1, the control system of the hybrid power engine includes an engine controller 1, a motor controller 2, an inverter 3, a battery 4, a hydraulic control device 5, an integrated controller 6, an accelerator opening sensor 7, and the like. The vehicle speed sensor 8, the engine speed sensor 9, the first motor generator speed sensor 10, the second motor generator speed sensor 11, and the third ring gear speed sensor 12 are configured. Yes.

  The engine controller 1 responds to a target engine torque command from the integrated controller 6 that inputs the accelerator opening AP from the accelerator opening sensor 7 and the engine speed Ne from the engine speed sensor 9, in accordance with the engine operating point (Ne, A command for controlling Te) is output to, for example, a throttle valve actuator (not shown).

  The motor controller 2 responds to a target motor generator torque command from the integrated controller 6 that inputs motor generator rotation speeds N1 and N2 from both motor generator rotation speed sensors 10 and 11 by a resolver, and the motor of the first motor generator MG1. A command for independently controlling the operating point (N1, T1) and the motor operating point (N2, T2) of the second motor generator MG2 is output to the inverter 3. The motor controller 2 outputs information on the battery S.O.C representing the state of charge of the battery 4 to the integrated controller 6.

  The inverter 3 is connected to a stator coil of the stator S common to the first motor generator MG1 and the second motor generator MG2, and generates a composite current according to a command from the motor controller 2. The inverter 3 is connected to a battery 4 that is discharged during power running and charged during regeneration.

  The hydraulic control device 5 receives a hydraulic command from the integrated controller 6 and performs engagement hydraulic pressure control and release hydraulic pressure control of the engine clutch EC, the low brake LB, the high clutch HC, and the high / low brake HLB. The engagement hydraulic pressure control and the release hydraulic pressure control include a half-clutch control based on a slip engagement control and a slip release control.

  The integrated controller 6 includes an accelerator opening AP from the accelerator opening sensor 7, a vehicle speed VSP from the vehicle speed sensor 8, an engine speed Ne from the engine speed sensor 9, and a first motor generator speed sensor 10. Information such as the first motor generator rotational speed N1, the second motor generator rotational speed N2 from the second motor generator rotational speed sensor 11, and the engine input rotational speed ωin from the third ring gear rotational speed sensor 12. Then, a predetermined calculation process is performed. Then, a control command is output to the engine controller 1, the motor controller 2, and the hydraulic control device 5 according to the calculation processing result.

  The integrated controller 6 and the engine controller 1 and the integrated controller 6 and the motor controller 2 are connected by bidirectional communication lines 14 and 15 for information exchange, respectively.

[Driving mode]
Since the hybrid power engine of the first embodiment can coaxially match the output shaft OUT of the transmission with the engine output shaft, the hybrid power engine is not limited to the FF vehicle (front engine / front drive vehicle) but also the FR vehicle (front engine It can be mounted on a rear drive vehicle) and is not divided into the low-side continuously variable gear ratio mode and the high-side continuously variable gear ratio mode, rather than covering the regular gear ratio range in one driving mode as the continuously variable gear ratio mode. Since the common gear ratio range is covered, the output sharing ratio by the two motor generators MG1 and MG2 can be suppressed to about 20% or less of the output generated by the engine E.

  As shown in FIG. 2, the traveling mode includes a low fixed speed ratio mode (hereinafter referred to as “Low mode”), a low-side continuously variable speed ratio mode (hereinafter referred to as “Low-iVT mode”), and 2-speed fixed mode (hereinafter referred to as “2nd mode”), high-side continuously variable gear ratio mode (hereinafter referred to as “High-iVT mode”), and high fixed gear ratio mode (hereinafter referred to as “High mode”). And 5) driving modes.

  As shown in FIG. 2, the Low mode is obtained by engaging the low brake LB, releasing the high clutch HC, and engaging the high / low brake HLB. The Low-iVT mode is obtained by engaging the low brake LB, releasing the high clutch HC, and releasing the high / low brake HLB. The 2nd mode is obtained by engaging the low brake LB, engaging the high clutch HC, and releasing the high / low brake HLB. The High-iVT mode is obtained by releasing the low brake LB, engaging the high clutch HC, and releasing the high / low brake HLB. The High mode is obtained by releasing the low brake LB, engaging the high clutch HC, and engaging the high / low brake HLB.

  For these five driving modes, the electric vehicle mode (hereinafter referred to as “EV mode”) in which only the motor generators MG1 and MG2 are driven without using the engine E, and the engine E and both motor generators MG1 and MG2 are used. And a hybrid vehicle mode (hereinafter referred to as “HEV mode”). Therefore, as shown in FIG. 3, when the EV mode and the HEV mode are combined, “10 driving modes” are realized. Figure 4 shows the EV-Low mode collinear diagram, EV-Low-iVT mode collinear diagram, EV-2nd mode collinear diagram, EV-High-iVT mode collinear diagram, EV-High A collinear chart of each mode is shown. Fig. 5 shows HEV-related HEV-Low mode alignment chart, HEV-Low-iVT mode alignment chart, HEV-2nd mode alignment chart, HEV-High-iVT mode alignment chart, HEV-High The collinear chart of each mode is shown.

  Here, the integrated controller 6 is preset with a travel mode map in which the “10 travel modes” are allocated in a three-dimensional space by the accelerator opening AP, the vehicle speed VSP, and the battery SOC. When traveling, the travel mode map is searched based on the detected values of the accelerator opening AP, the vehicle speed VSP, and the battery SOC, and the optimal travel mode is selected according to the vehicle operating point and battery charge determined by the accelerator opening AP and the vehicle speed VSP. The

  When the mode is changed between the “EV mode” and the “HEV mode” by selecting the travel mode map, the engine clutch EC engagement control and the engine clutch EC Release control, or in addition, engagement / release control of engagement elements such as clutches and brakes is executed. In addition, when performing mode transition between the five modes of “EV mode” and mode transition between the five modes of “HEV mode”, the engagement / release control of the engagement elements such as clutches and brakes is executed. Is done. These mode transition controls are performed by sequence control according to a predetermined procedure so that the engine operating point and the motor operating point are smoothly transferred.

[Transmission ratio stabilization control / drive torque control configuration of hybrid power engine]
FIG. 6 is an overall block diagram showing a transmission ratio stabilization control / drive torque control system of a hybrid power engine to which the engine torque control device of the hybrid vehicle of the first embodiment is applied, and FIG. 7 is an engine torque of the hybrid vehicle of the first embodiment. It is a principal part block diagram which shows the gear ratio stabilization control / drive torque control system of the hybrid power engine to which the control apparatus was applied.

  The transmission ratio stabilization control / drive torque control configuration of the hybrid power engine includes a hybrid power engine 20, an operating point command unit 21, a battery actual power comparison / difference unit 22, a first integrator 23, and a divider 24. A first subtractor 25 (engine torque command value correcting means), a second subtractor 26, a third subtractor 27, a gear ratio control / driving force control / torque distributor 28, and a fourth subtractor 29. And a second integrator 30. The operating point command unit 21 to the transmission ratio control / driving force control / torque distributor 28 simulate the processing performed by the integrated controller 6, and the fourth subtractor 29 and the second integrator. Reference numeral 30 represents a process performed by a hybrid vehicle equipped with the hybrid power engine 20.

  The hybrid power engine 20 includes a first motor generator MG1 driven by a first motor torque command value T1 ref from the transmission ratio control / driving force control / torque distributor 28, and the transmission ratio control / driving force control / The second motor generator MG2 is driven by the second motor torque command value T2 ref from the torque distributor 28, and is driven by the engine torque correction command value Te ref1 from the speed ratio control / driving force control / torque distributor 28. And an engine E. Then, the first motor torque T1 act, the second motor torque T2 act, and the engine torque Te act are input, and the actual driving torque value To act (or the estimated driving torque value To estim), the engine speed Ne act, and the battery power Pb act And a planetary gear transmission.

  The operating point command unit 21 outputs a drive torque command value To ref, an engine speed command value Ne ref, and an engine torque command value Te ref based on various types of input information.

  The battery actual power comparison / difference unit 22 inputs the battery power Pb act and compares the battery power Pb act with the minimum allowable range by comparing with a preset battery charge / discharge power allowable range characteristic diagram (FIG. 8). When the value is greater than the value PbL and less than or equal to the maximum allowable range PbH, 0 is output. When the battery power Pb act exceeds the minimum allowable range PbL, the excess difference (PbL-Pb act) is output and the battery is output. When the power Pb act exceeds the allowable range maximum value PbH, the excess difference (Pb act−PbH) is output.

  The first integrator 23 integrates the difference exceeding the battery actual power comparison / difference unit 22 with an integration time constant Tie, and outputs an integrated value.

  The divider 24 divides the integral value from the first integrator 23 by the engine speed actual value Ne act (= engine speed Ne) and outputs a corrected value Te Pb. The correction value Te Pb has a lower limit when the engine speed is low.

  The first subtracter 25 calculates the engine torque correction command value Te ref1 by subtracting the correction value Te Pb from the divider 24 from the engine torque command value Te ref from the operating point command unit 21.

  The second subtractor 26 calculates the drive torque deviation command value ΔTo ref by subtracting the actual drive torque value To act from the drive torque command value To ref from the operating point command unit 21.

  The third subtracter 27 calculates an engine speed deviation command value ΔNe ref by subtracting the engine speed Ne act from the engine speed command value Ne ref from the operating point command unit 21.

As shown in FIG. 7, the speed ratio control / driving force control / torque distributor 28 includes an engine rotation acceleration calculation means 28a and a torque distribution means 28b, and includes a first motor torque command value T1 ref and a first 2 Outputs the motor torque command value T2 ref and the engine torque command value Te ref1. The engine rotational acceleration calculating means 28a calculates an engine rotational acceleration command value dNe ref based on the engine rotational speed deviation command value ΔNe ref from the third subtractor 27.
The torque distribution means 28b is configured to generate a first motor torque command value T1 ref and a second motor torque based on the running resistance torque, the engine torque, the drive torque deviation command value ΔTo ref, and the engine rotation acceleration command value dNe ref. Calculate command value T2 ref. Here, the running resistance torque is estimated using a disturbance observer.
In the transmission ratio control / driving force control / torque distributor 28, when the first motor torque command value T1 ref and the second motor torque command value T2 ref are calculated using the equation of motion for each rotating element of the planetary gear transmission, Since the motor torque command value that satisfies the drive torque command value To ref and the engine speed command value Ne ref is calculated, a change in the drive torque does not delay the realization of the engine speed command value. As a result, the target drive torque and the target engine rotation speed (= transmission ratio) can be realized with high accuracy, and a driving feeling close to the driver's desire can be obtained.

  The fourth subtractor 29 subtracts the disturbance Td (running resistance, friction in the power transmission engine, etc.) from the actual driving torque value To act from the planetary gear transmission, and outputs a vehicle driving torque command value Tv act.

  The second integrator 30 receives the vehicle drive torque command value Tv act from the fourth subtractor 29, integrates it with the vehicle inertia integration time constant Jv, and outputs the output rotational speed measured value No act (= vehicle speed VSP). To do.

Next, the operation will be described.
[Engine torque control processing]
FIG. 9 is a flowchart showing the flow of the engine torque control process executed by the integrated controller 6 according to the first embodiment. Each step will be described below.

  In step S1, it is determined whether the vehicle speed VSP is VSP> 0, that is, whether or not the vehicle is traveling. If YES, the process proceeds to step S2, and if NO, the determination in step S1 is repeated.

In step S2, the actual power Pb (t) of the battery 4 is detected by calculation using the following equation, and the process proceeds to step S3 (battery actual power detection means).
Pb (t) = V (t) × I (t)
However, V (t) is a battery voltage measurement value, and I (t) is a battery current measurement value.

  In step S3, it is determined whether or not the actual battery power Pb (t) (= battery power Pb act) calculated in step S2 exceeds the allowable range maximum value PbH. If YES, the process proceeds to step S4. If NO, the process proceeds to step S5.

In step S4, based on the determination that Pb (t)> PbH in step S3, a corrected value Te Pb (positive value) is calculated according to the difference (Pb (t) −PbH) that has exceeded, and the process proceeds to step S7. To do.
Here, for example, as shown in FIG. 8, the correction value Te Pb is obtained by integrating an excess difference (Pb (t) −PbH) with an integration time constant Tie to obtain an integration value A. Calculated by dividing by the engine speed Ne.

  In step S5, it is determined whether or not the actual battery power Pb (t) (= battery power Pb act) calculated in step S2 exceeds the allowable minimum value PbL. If YES, the process proceeds to step S6. If NO, the process proceeds to step S7.

In step S6, based on the determination of Pb (t) <PbL in step S5, a corrected value Te Pb (negative value) is calculated according to the difference (PbL−Pb (t)), and the process proceeds to step S7. To do.
Here, for example, as shown in FIG. 8, the correction value Te Pb is obtained by integrating an excess difference (PbL−Pb (t)) with an integration time constant Tie to obtain an integration value B. Calculated by dividing by the engine speed Ne.

In step S7, the engine torque correction command value Te ref1 is calculated by subtracting the correction value Te Pb from the engine torque command value Te ref, and the process proceeds to step S8.
Here, when the process proceeds from step S4 to step S7 (Pb (t)> PbH),
Te ref1 ＝ Te ref−Te Pb
The engine torque correction command value Te ref1 is calculated by the following formula, and the engine torque command value Te ref is decreased and corrected to subtract the correction value Te Pb from the engine torque command value Te ref.
When the process proceeds from step S6 to step S7 (Pb (t) <PbL),
Te ref1 = Te ref + Te Pb
The engine torque correction command value Te ref1 is calculated by the following formula, and is increased and corrected to add the correction value Te Pb to the engine torque command value Te ref.
Further, when the process proceeds from step S5 to step S7 (PbL ≦ Pb (t) ≦ PbH),
Te ref1 = Te ref + 0
The engine torque correction command value Te ref1 (= Te ref) is calculated by the following equation.

  In step S8, torque control of the engine E is executed based on the engine torque correction command value Te ref1 calculated in step S7, and the process proceeds to return.

  [Background Technology of Engine Torque Control Device]

  Conventionally, there is a motor overload protection method based on drooping characteristics (drooping) as a protection against failure due to overpower of the power storage means (for example, Japanese Patent Laid-Open No. 6-38586, name: control device for inverter for driving motor) .

When driving a common load mechanically coupled by a plurality of motors, if the speed of each of the plurality of motors is controlled, the speed error of each speed control may vary due to speed detection errors and variations in each motor. Since the torque cannot be zero at the same time, and the torque is corrected through the speed control of each motor due to the speed error that is different for each motor, the torque sharing of each motor and thus the load sharing is not equalized, and the specific motor is overloaded. It will cause a load and trip, which will hinder the overall operation.
In order to prevent this, an excessive load is applied to each motor by applying so-called drooping characteristics (drooping), which reduces the speed command of the motor according to the driving torque. Since the speed command is reduced according to the torque, the load on the motor is reduced and tripping is prevented. A similar problem occurs even when a load having constant speed characteristics is driven by a speed control motor, and is a function added to the speed control drive device as a motor protection function.
However, since the above-mentioned conventional device is a protection of the motor and a protection by detecting the torque current, it cannot be directly applied to the purpose of protecting the battery of the hybrid vehicle. Although the conventional apparatus is applied to speed control, in a hybrid vehicle, since it is generally torque control rather than speed control, the speed command cannot have a drooping characteristic as well. In particular, in a hybrid vehicle in which a plurality of generators / motors are connected to a common battery via each or a common drive unit, any generator / motor can be used in a method in which the drooping characteristic is kept as it is in the torque command for torque control. It is unclear whether the motor command should be corrected.

  There is also a method of calculating the battery power using the power transmission system parameters and the speed detection value / torque estimation value and correcting the torque command of each motor so that it is within the allowable range. When the rotational speed of the motor changes, the increase / decrease in the kinetic energy must be calculated accurately, and the exact value of the rotational inertia needs to be known. Since this is generally difficult, the calculated battery power is not accurate and may deviate from the tolerance by an error. Moreover, in a hybrid power engine having a continuously variable transmission ratio mode, even if accurate battery power is calculated, the correction amount of the torque command of each motor depends on the parameters of the power transmission system. If there is an error, the correction amount cannot be obtained accurately, and the battery power does not fall within the allowable range even after correction.

[Engine torque control action]
On the other hand, the engine torque control device of the first embodiment solves these problems of the related art by the closed loop control of “integrating the amount deviated from the battery allowable power and correcting the engine torque command value by this”. To do.

  That is, when the actual battery power Pb (t) exceeds the allowable range maximum value PbH, in the flowchart shown in FIG. 9, the process proceeds from step S1, step S2, step S3, step S4, step S7, and step S8. In step S4, the difference (Pb (t) −PbH) exceeding is integrated with the integration time constant Tie to obtain an integral value A, and the integral value A is divided by the engine speed Ne to obtain a corrected value Te. Pb is calculated, and in step S7, the engine torque correction command value Te ref1 is calculated by the formula Te ref1 = Te ref−Te Pb, that is, the reduction correction by subtracting the correction value Te Pb from the engine torque command value Te ref. In S8, torque control of the engine E is executed based on the engine torque correction command value Te ref1.

  Therefore, the battery power consumption by the first motor generator MG1 and the second motor generator MG2 increases by the amount of the corrected correction of the engine torque command value Te ref, and the battery actual power Pb (t) gradually approaches the allowable range maximum value PbH. . In addition, since the difference (Pb (t) – PbH) exceeding the corrected value Te Pb is obtained by integrating the integrated time constant Tie, the actual battery power Pb (t) is the maximum allowable value. Regardless of the difference (Pb (t) -PbH) exceeding the maximum allowable range PbH, the battery power consumption by the first motor generator MG1 and the second motor generator MG2 increases as the value exceeds PbH. The battery actual power Pb (t) can be brought close to the allowable range maximum value PbH with good response. Further, since the correction value Te Pb is obtained by dividing the integral value A by the engine speed Ne, the correction value Te Pb decreases as the engine speed increases. For example, the correction value Te Pb increases at the low gear ratio. Deterioration effects (such as front-rear G fluctuations) on vehicle behavior due to engine torque reduction during acceleration traveling due to engine speed can be reduced.

  Thereafter, when the actual battery power Pb (t) falls within the allowable range of the allowable range minimum value PbL and the allowable range maximum value PbH or less, in the flowchart shown in FIG. 9, step S1, step S2, step S3, step S5, step In step S7, the engine torque command value Te ref is directly used as the engine torque correction command value Te ref1. In step S8, the torque of the engine E is determined based on the engine torque correction command value Te ref1. Control is executed. That is, traveling that obtains the engine torque command value Te ref is ensured while keeping the actual battery power Pb (t) within the allowable range.

  Thereafter, when the actual battery power Pb (t) exceeds the allowable range minimum value PbL, in the flowchart shown in FIG. 9, step S1, step S2, step S3, step S5, step S6, step S7, step S8. In step S6, the difference (Pb (t) −PbH) exceeding is integrated with an integration time constant Tio to obtain an integral value B, and this integral value B is divided by the engine speed Ne. The correction value Te Pb is calculated, and in step S7, the engine torque correction command value Te ref1 is calculated by the formula of Te ref1 = Te ref + Te Pb, that is, the incremental correction by adding the correction value Te Pb to the engine torque command value Te ref, In step S8, torque control of the engine E is executed based on the engine torque correction command value Te ref1.

  Therefore, the battery power consumption by the first motor generator MG1 and the second motor generator MG2 is reduced by the increase correction of the engine torque command value Te ref, and the battery actual power Pb (t) gradually approaches the allowable range minimum value PbL. . In addition, since the difference (PbL−Pb (t)) exceeding the corrected value Te Pb is obtained by integrating the integral time constant Tie, the battery actual power Pb (t) is the maximum allowable range. Regardless of the difference (PbL-Pb (t)) exceeding the minimum allowable range PbL, the battery power consumption by the first motor generator MG1 and the second motor generator MG2 decreases as PbL is greatly exceeded. The battery actual power Pb (t) can be brought close to the allowable range minimum value PbL with good response. Furthermore, since the correction value Te Pb is obtained by dividing the integral value B by the engine speed Ne, the correction value Te Pb decreases as the engine speed increases. For example, the correction value Te Pb increases at a low gear ratio. Deterioration effects (such as front-rear G fluctuations) on vehicle behavior due to engine torque reduction during acceleration traveling due to engine speed can be reduced.

  Therefore, based on the actual battery power Pb (t), not the calculated battery power, the engine torque command value Te ref is adjusted according to the amount outside the allowable range. As a result, the battery actual power Pb (t) is closed-loop controlled within the allowable range, and stable vehicle travel is maintained in which the battery actual power Pb (t) is maintained within the allowable range. Moreover, since the battery actual power Pb (t) is an actual value including the increase and decrease of the kinetic energy of the rotating element, there is no problem of an error in the battery power calculation value caused by an error in the rotational inertia.

  Furthermore, in a hybrid power engine having a continuously variable transmission ratio, a speed change occurs in the power transmission system (the ratio of the rotational speed of the rotating elements changes), so that the kinetic energy of the power transmission system can be calculated more accurately. Although difficult, actual battery power Pb (t) including this is possible.

  In addition, the corrected value Te Pb is obtained by integrating the difference exceeding the allowable range with the integration time constant Tie, and dividing this integrated value by the engine speed Ne, so driving at a low engine speed Sometimes, regardless of the magnitude of the difference beyond the allowable range, the response to return to the allowable range can be ensured, and when driving at high engine speeds, the increase / decrease width of the engine torque is kept small, thereby improving vehicle behavior stability. Can be secured. When the engine speed Ne where the correction value Te Pb is excessive is small, the calculation / correction is stopped by the lower limit, but there is no problem because the engine speed Ne does not become equal to or lower than the idle speed.

Next, the effect will be described.
In the engine torque control device of the hybrid vehicle according to the first embodiment, the effects listed below can be obtained.

  (1) A gear transmission mechanism that connects the engine E, one or more motor generators MG1 and MG2 connected to the battery 4 via the inverter 3, and the output shaft of the engine E, the motor shaft, and the output shaft to the tire. And a battery actual power detection means for detecting the actual power of the battery 4 and the actual battery power is discharged beyond a battery charge / discharge power allowable range determined from a battery state. The engine torque command value Te ref is increased according to the excess amount, and when charging exceeds the battery charge / discharge power allowable range, the engine torque command value Te is increased according to the excess amount. engine torque command value correction means for reducing ref, and battery power calculation due to rotational inertia error when driving with hybrid vehicle mode selected No problems such error, it is possible to secure stable running while keeping the battery performance power within the allowable range.

  (2) Engine E, one or more motor generators MG1 and MG2 connected to battery 4 via inverter 3, and output shaft OUT of engine E, motor shaft, and output shaft OUT to the tire differ by two degrees of freedom. In the hybrid vehicle connected to the rotating element of the dynamic gear speed change mechanism, the battery actual power detection means for detecting the actual power of the battery 4 and the battery charge / discharge power allowance in which the battery actual power is determined from the battery state If the battery is discharged beyond the range, the engine torque command value Te ref will be increased according to the excess, and if the battery charge / discharge power is charged beyond the allowable range, the battery will be charged accordingly. Engine torque command value correcting means for reducing the engine torque command value Te ref. There is no problem of re-power calculation value error, it is possible to ensure stable running while keeping the actual battery power within the allowable range, and at the time of running with the continuously variable speed ratio mode selected, the power transmission system In particular, since shifting occurs (the ratio of the rotational speeds of the rotating elements changes), accurate calculation of the kinetic energy of the power transmission system is more difficult, but actual battery power including this is possible. Further, since the battery power Pb act is controlled by adjusting the engine torque, the target driving force is achieved.

  (3) The engine torque command value correcting means integrates the amount exceeding the battery charge / discharge power allowable range with an integral time constant Tie, and further divides the integral value by the engine speed Ne to obtain an engine torque command value. Since correction is made by adding or subtracting to the value Te ref, when driving at low engine speed, the return response to the allowable range can be ensured regardless of the magnitude of the difference exceeding the allowable range, and the high engine speed When running at, vehicle behavior stability can be ensured by keeping the engine torque variation small. In other words, since the battery power correction is performed in a form in which the degree of influence due to the change in the engine speed Ne is corrected, stable battery power correction can be performed without depending on the engine speed Ne.

  As mentioned above, although the engine torque control apparatus of the hybrid vehicle of this invention has been demonstrated based on Example 1, it is not restricted to this Example 1 about a concrete structure, Each claim of a claim is a claim. Design changes and additions are allowed without departing from the gist of the invention.

  For example, in the first embodiment, as the engine torque command value correcting means, the amount exceeding the battery charge / discharge power allowable range is integrated by an integration time constant, and a value obtained by dividing the integration value by the engine speed is calculated as engine torque. Although an example of correction by adding or subtracting to the command value has been shown, as a specific method for correcting the drive torque command value, for example, if the correction is in accordance with the amount exceeding the battery charge / discharge power allowable range, Correction may be performed in proportion to that amount, or proportional integral calculation may be performed. Further, other methods used for closed loop control may be used.

  The engine torque control device for a hybrid vehicle according to the present invention is not limited to application to a hybrid vehicle having a differential gear transmission mechanism with two degrees of freedom as shown in the first embodiment, but other gear transmission mechanisms, belt types, and toroidal types. The present invention can also be applied to a series / parallel hybrid vehicle having a continuously variable transmission mechanism.

1 is an overall drive system diagram of a hybrid vehicle to which an engine torque control device according to a first embodiment is applied. It is a figure which shows the fastening / release state of three engagement elements in each driving mode in a hybrid power engine. It is a figure which shows each operation | movement table | surface of the engine * engine clutch * motor generator * low brake * high clutch * high low brake in five driving modes in an electric vehicle mode and five driving modes in a hybrid vehicle mode in a hybrid power engine. . It is a collinear diagram which shows five driving modes in the electric vehicle mode in a hybrid power engine. It is a collinear diagram which shows five driving modes in a hybrid vehicle mode in a hybrid power engine. 1 is an overall block diagram illustrating a transmission ratio stabilization control / drive torque control system of a hybrid power engine to which an engine torque control device for a hybrid vehicle according to a first embodiment is applied. It is a principal block diagram showing a gear ratio stabilization control / drive torque control system of a hybrid power engine to which an engine torque control device for a hybrid vehicle of Example 1 is applied. It is a battery charge / discharge power allowable range characteristic diagram preset in the battery actual power comparison / difference device of the first embodiment. 3 is a flowchart showing a flow of an engine torque control process executed by an integrated controller 6 of the first embodiment.

Explanation of symbols

E engine
MG1 1st motor generator
MG2 Second motor generator
OUT output shaft
PG1 1st planetary gear
PG2 2nd planetary gear
PG3 3rd planetary gear
EC engine clutch
LB Low brake
HC high clutch
HLB High / Low Brake 1 Engine Controller 2 Motor Controller 3 Inverter (Driver)
4 Battery 5 Hydraulic Control Device 6 Integrated Controller 20 Hybrid Power Engine 21 Operating Point Command Unit 22 Battery Actual Power Comparison / Differential Unit 23 First Integrator 24 Divider 25 First Subtractor (Engine Torque Command Value Correction Means)
26 Second subtractor 27 Third subtractor 28 Gear ratio control / driving force control / torque distributor 29 Fourth subtractor 30 Second integrator

Claims (3)

A hybrid composed of main power means, one or more motors connected to the battery via a drive unit, and a speed change mechanism that connects the output shaft of the main power means, the motor shaft, and the output shaft to the tire. In the car,
Battery actual power detection means for detecting the actual power of the battery;
When the battery actual power is discharged exceeding the battery charge / discharge power allowable range determined from the battery state, the engine torque command value is increased according to the excess, and the battery charge / discharge power allowable range is increased. Engine charge command value correcting means for reducing the engine torque command value in accordance with the excess,
An engine torque control device for a hybrid vehicle, comprising: The main power means, one or more motors connected to the battery via a drive unit, and the output shaft of the main power means, the motor shaft, and the output shaft to the tire are the rotational elements of the differential gear transmission mechanism with two degrees of freedom. In connected hybrid vehicles,
Battery actual power detection means for detecting the actual power of the battery;
When the battery actual power is discharged exceeding the battery charge / discharge power allowable range determined from the battery state, the engine torque command value is increased according to the excess, and the battery charge / discharge power allowable range is increased. Engine charge command value correcting means for reducing the engine torque command value in accordance with the excess,
An engine torque control device for a hybrid vehicle, comprising: In the engine torque control device for a hybrid vehicle according to claim 1 or 2,
The engine torque command value correcting means integrates the amount exceeding the battery charge / discharge power allowable range with an integral time constant, and further adds or subtracts the value obtained by dividing the integral value by the engine speed to the engine torque command value. The engine torque control device for a hybrid vehicle is characterized in that the correction is performed.

Images