JP3995835B2 - Power control apparatus in a vehicle including an electric motor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a power control device in a vehicle including an actuator such as an electric motor, and more particularly to a power control device that suppresses vibrations generated in a power output mechanism due to fluctuations in drive torque of the power output mechanism.
[0002]
[Prior art]
In recent years, a technique for suppressing vibration caused by a disturbance using a disturbance observer has been proposed. As a technique for suppressing the vibration caused by the disturbance from the outside of the apparatus with the required torque being substantially constant, for example, there is a technique disclosed in Japanese Patent Laid-Open No. 9-305203. In this technology, in the tracking servo system of an optical disk device, when driving and controlling an actuator that performs tracking, an apparent drive signal is obtained using an inverse transfer function model of the actuator and compared with a drive signal for the actuator. , Estimating disturbance factors. And the influence of the disturbance with respect to the drive control of an actuator is suppressed by the feedback control which considered the estimated disturbance element.
[0003]
In addition, as a technology for suppressing vibration caused by the required torque that changes with time, Toyota Central Research Institute report TR-55 discloses a technology for independently controlling the rear wheel driving force by a motor. Yes. According to this disclosed technique, by estimating the disturbance, a large vibration of the wheel torque generated by a slight fluctuation of the motor torque is suppressed. Specifically, the estimated torque value of the model is calculated using a highly accurate inverse model to be controlled, and the disturbance is estimated by comparing the required torque value with the estimated torque value. Then, the control torque value based on the estimated disturbance is added to the required torque value, and the disturbance is suppressed.
[0004]
[Problems to be solved by the invention]
However, in the former, since the driving torque required for the actuator is substantially constant, the disturbance is caused solely by vibrations from the outside of the device, and vibrations generated by torque fluctuations, that is, the device itself. The vibration generated from is not taken into account. Therefore, it cannot be applied as it is to a vehicle whose required torque value changes with time.
[0005]
In the latter case, it is very difficult to identify a highly accurate inverse model to be controlled in implementation, and there is a problem in that control using such an inverse model is complicated. Furthermore, there has been a problem that it is not possible to reflect changes in characteristics caused by aging of the actual model.
An object of the present invention is to perform high-speed control of driving torque while suppressing vibration of a power unit in a vehicle including an electric motor in the power unit.
[0006]
[Means for solving the problems and their functions and effects]
The present invention has been made to solve the above-mentioned problems, and a first aspect of the present invention includes a power output mechanism having at least one actuator and capable of outputting a required torque from the actuator via a drive shaft. A control device for controlling the power output mechanism by providing a torque command value to the actuator so that the output of the power output mechanism becomes the required torque is set as the control target. The control device is configured to detect a torque output from the power output mechanism using a detection unit that detects a parameter correlated with the torque output from the actuator and a target inverse model of the power output mechanism from the detected parameter. An estimation means for estimating the estimated drive torque and a torque compensation means for compensating the torque command value so that the torque command value matches the estimated drive torque are provided.
According to the first aspect, torque fluctuations generated in the power output mechanism can be effectively suppressed.
[0007]
Here, the torque compensation means is a disturbance torque estimation means for estimating a deviation between the estimated drive torque and the torque command value as a disturbance torque, and multiplies the estimated disturbance torque by a predetermined gain to obtain a control torque. It is preferable to include a control torque calculation means to be obtained, a torque command value calculation means for compensating the torque command value from the obtained control torque and the required torque for the power output mechanism.
By providing such a component, the driving torque can be controlled at high speed while suppressing the vibration of the power output mechanism.
[0008]
The predetermined gain is preferably a value determined based on a ratio of a mass of the power output mechanism and a mass of the vehicle. By providing such a component, the vibration of the power output mechanism due to the fluctuation of the drive torque output from the power output mechanism can be more effectively suppressed.
[0009]
Next, a second aspect of the present invention controls a power output mechanism in a vehicle having at least an electric motor and an internal combustion engine and a power output mechanism capable of outputting a required torque from the electric motor via a drive shaft. Provided is a control device that controls the target. The control device includes, based on at least an accelerator opening and a vehicle speed, required torque calculation means for calculating the required torque, rotation speed detection means for detecting the rotation speed of the electric motor, and based on the detected rotation speed, the power An estimation unit that estimates a torque output from the power output mechanism as an estimated drive torque using a target inverse model of the output mechanism, and an output from the power output mechanism is given to the power output mechanism so as to be the required torque. Torque compensation means for compensating the torque command value based on the estimated driving torque is provided.
According to the second aspect, vibration generated in the power output mechanism can be effectively suppressed.
[0010]
Here, the torque compensation means is a disturbance torque estimation means for estimating a deviation between the estimated drive torque and the torque command value as a disturbance torque, and multiplies the estimated disturbance torque by a predetermined gain to obtain a control torque. It is preferable to include a control torque calculation means to be obtained, a torque command value calculation means for compensating the torque command value from the obtained control torque and the required torque for the power output mechanism.
By providing such a component, the driving torque can be controlled at high speed while suppressing the vibration of the power output mechanism.
[0011]
The predetermined gain is preferably a value determined based on a ratio of a mass of the power output mechanism and a mass of the vehicle. By providing such a component, the vibration of the power output mechanism due to the fluctuation of the drive torque output from the power output mechanism can be more effectively suppressed.
[0012]
According to a third aspect of the present invention, in a vehicle having at least an electric motor and including a power output mechanism capable of outputting a required torque from the electric motor via a drive shaft, the power output mechanism is a control target and the control is performed. A control device is provided. This control device detects a required torque input means for inputting the required torque via a filter that suppresses initial fluctuation caused by a difference between the mass of the vehicle and the mass of the power output mechanism, and detects the rotation speed of the electric motor. A rotational speed detection means; an estimation means for estimating a torque output from the power output mechanism as an estimated drive torque from the detected rotational speed using a target inverse model of the power output mechanism; and Torque compensation means for compensating a torque command value given to the power output mechanism based on the estimated driving torque so that the output becomes the required torque input through the filter.
According to the third aspect, the drive torque can be controlled at high speed while suppressing the vibration of the power output mechanism. In particular, the initial vibration due to the mass difference between the vehicle and the power output mechanism can be effectively suppressed.
[0013]
The power output mechanism includes an internal combustion engine, and the estimation means estimates and drives the torque output by the power output mechanism from the detected rotational speed using a target inverse model of the power output mechanism including the internal combustion engine. It may be estimated as torque. With such a configuration, even in a vehicle including an electric motor and an internal combustion engine as a power output mechanism, the drive torque can be controlled at high speed while suppressing vibration of the power output mechanism.
[0014]
In addition, the filter may be a filter that exhibits low responsiveness to the initial input and high responsiveness to the subsequent input, and further conforms to the characteristics of a quadratic function curve. Is preferred. By providing such a component, effective suppression of the initial vibration caused by the mass difference between the vehicle and the power output mechanism can be more appropriately realized.
[0015]
According to a fourth aspect of the present invention, in a vehicle including at least a motor and a power output mechanism capable of outputting a required torque from the motor via a drive shaft, the power output mechanism is a control target, and the power output mechanism A control device is provided for controlling the power output mechanism by giving a torque command value to the electric motor so that the output of the motor becomes the required torque. This control device uses a required torque calculation means for calculating a required torque based on at least the accelerator opening and the vehicle speed, a rotation speed detection means for detecting the actual rotation speed of the electric motor, and a positive model of the power output device, Rotational speed estimation means for estimating the estimated rotational speed of the electric motor from the torque command value, and torque compensation means for compensating the torque command value so that the actual rotational speed matches the estimated rotational speed. Features.
According to the fourth aspect, it is possible to effectively suppress the vibration generated in the power output mechanism.
[0016]
Here, the torque compensation means includes a rotational speed fluctuation estimating means for estimating a deviation between the estimated rotational speed and the actual rotational speed as a rotational speed fluctuation due to a disturbance torque, and converts the estimated rotational speed fluctuation into torque. The torque command value calculating means for compensating the torque command value from the control torque calculating means for multiplying the torque by a predetermined gain and obtaining the control torque, the obtained control torque, and the required torque for the power output mechanism. It is preferable to comprise.
By providing such a component, the driving torque can be controlled at high speed while suppressing the vibration of the power output mechanism.
[0017]
The power output mechanism includes an internal combustion engine, and the rotational speed estimation means estimates the estimated rotational speed of the electric motor from the torque command value using a positive model of the power output mechanism including the internal combustion engine. There may be. In such a case, even in a vehicle including an electric motor and an internal combustion engine as a power output mechanism, the drive torque can be controlled at high speed while suppressing vibration of the power output mechanism.
[0018]
Here, in the control device according to the first to fourth aspects, the target model of the power output mechanism may be a single inertia model that does not include a vibration system. In this case, the identification of the model can be executed relatively easily, and the execution of the control can be executed simply.
[0019]
Furthermore, a fifth aspect of the present invention provides a vehicle including any one of the power control devices among the control devices according to the first to fourth aspects.
According to the fifth aspect, the vibration of the power output mechanism in the vehicle is suppressed, and the drive torque is controlled at high speed.
[0020]
According to a sixth aspect of the present invention, in a vehicle having at least one actuator and including a power output mechanism capable of outputting a required torque from the actuator via a drive shaft, the power output mechanism is a control target, and the power Provided is a control method for controlling the power output mechanism by giving a torque command value to the actuator so that the output of the output mechanism becomes the required torque. In this control method, a parameter correlated with the torque output by the actuator is detected, and the torque output by the power output mechanism is estimated from the detected parameter using the target inverse model of the power output mechanism. And the torque command value is compensated so that the torque command value matches the estimated driving torque.
According to the sixth aspect, the drive torque can be controlled at high speed while suppressing the vibration of the power output mechanism.
[0021]
According to a seventh aspect of the present invention, in a vehicle including at least a motor and an internal combustion engine, and including a power output mechanism capable of outputting a required torque from the motor via a drive shaft, the power output mechanism is a control target. A control method for performing the control is provided. This control method calculates the required torque based on at least the accelerator opening and the vehicle speed, detects the rotational speed of the electric motor, and uses the target inverse model of the power output mechanism from the detected rotational speed, The torque output by the power output mechanism is estimated as the estimated drive torque, and the torque command value given to the power output mechanism is compensated based on the estimated drive torque so that the output of the power output mechanism becomes the required torque. It is characterized by doing.
According to the seventh aspect, the drive torque can be controlled at high speed while suppressing the vibration of the power output mechanism.
[0022]
According to an eighth aspect of the present invention, in a vehicle having at least an electric motor and including a power output mechanism capable of outputting a required torque from the electric motor via a drive shaft, the power output mechanism is a control target and the control is performed. Provide a control method. In this control method, the required torque is input through a filter that suppresses initial vibration caused by the difference between the mass of the vehicle and the mass of the power output mechanism, and the rotational speed of the electric motor is detected and detected. The torque output from the power output mechanism is estimated as the estimated drive torque from the rotational speed using the target inverse model of the power output mechanism, and the output of the power output mechanism is converted into the required torque input through the filter. The torque command value given to the power output mechanism is compensated based on the estimated driving torque.
According to the seventh aspect, the drive torque can be controlled at high speed while suppressing the vibration of the power output mechanism.
[0023]
According to a ninth aspect of the present invention, in a vehicle including at least a motor and a power output mechanism capable of outputting a required torque from the motor via a drive shaft, the power output mechanism is a control target, and the power output mechanism A control method is provided for controlling the power output mechanism by giving a torque command value to the electric motor so that the output of the motor becomes the required torque. This control method calculates a required torque based on at least the accelerator opening and the vehicle speed, detects the actual rotational speed of the electric motor, and uses the positive model of the power output device to estimate the estimated rotational speed of the electric motor from the torque command value. And the torque command value is compensated so that the actual rotational speed matches the estimated rotational speed.
According to the ninth aspect, the drive torque can be controlled at high speed while suppressing the vibration of the power output mechanism.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a power control apparatus in a vehicle including an electric motor as a power unit according to the present invention will be described in detail according to some preferred embodiments of the present invention with reference to the drawings.
[0025]
Embodiment of the first invention:
FIG. 1 shows an example of a schematic configuration diagram of a vehicle including an electric motor as a power unit to which the present invention can be applied. A vehicle 10 shown in FIG. 1 includes an electric motor (motor) 11 in a power unit, an output shaft of the motor 11 is coupled to a power train 12, and the power train 12 is connected to wheels 13a and 13b. The motor 11 is an AC motor, and a battery 15 is connected to the motor 11 via an inverter 14. The direct current of the battery 15, which is a direct current power supply, is supplied to the motor 11 after being converted into an alternating current. At the time of the regenerative operation in which the motor 11 functions as a generator, the generated alternating current is converted into a direct current. Is stored. Here, the battery 15 includes a power source such as a secondary battery and a power capacitor.
[0026]
In the vehicle 10 having such a configuration, the motor 11 is driven and controlled by the control unit 16. The control unit 16 includes a CPU 17 that executes a control program, which will be described later, a ROM 18 that stores a control program and the like, a RAM 19 that temporarily stores detection data, a calculation result by the CPU 17, and the like. Connected to the control unit 16 are an accelerator position sensor 20 that detects the amount of depression of the accelerator pedal (accelerator opening), and a vehicle speed sensor 21 that detects the vehicle speed based on the output shaft rotational speed of the motor 11. . The control unit 16 calculates the required torque based on the detected accelerator pedal depression amount and vehicle speed.
The control unit 13 controls the drive of the motor 11 via the inverter 14 based on the calculated required torque. The driving torque output from the motor 11 is transmitted to the wheels 13a and 13b via the power train 12.
[0027]
FIG. 2 is a schematic diagram schematically showing a vibration system used in common in the first, second and third embodiments. The power unit 30 is swingably coupled to the chassis 32 via a mount 31 that is schematically represented in the form of a spring. The output shaft 33 of the power unit 30 is coupled to one end of a drive shaft 34 that represents the power train, and the torsion of the drive shaft 34 is represented by a torsion spring. The other end of the drive shaft 34 is coupled to a wheel 35 that acts as load inertia.
[0028]
In the first and second embodiments, a motor (electric motor) is provided as the power unit 30, the output shaft 33 of the power unit 30 is coupled to the motor rotor 36, and the housing of the power unit 30 is a motor stator. 37.
[0029]
In the schematic diagram of FIG. 2, when a driving torque is applied in the arrow direction A, a torque reaction force acts in the arrow direction B. Due to this torque reaction force and its swing back, vibration is generated in the power unit 30 supported via the mount 2, and the vibration appears on the motor rotor 36. Further, vibration due to the twist of the drive shaft 34 also appears in the motor rotor 36.
[0030]
FIG. 3 shows a block diagram of a control system used in the embodiment of the present invention. The control target in this control system is a response delay (power output mechanism) of the power unit, the power train, and the motor ECU.
The required torque is the drive torque that the power unit requested by the power unit (motor in the embodiment of the present invention) should output. For example, the required torque is calculated by the required torque calculator 40 (required torque calculation means) based on the accelerator opening and the vehicle speed. It is determined. The actual vehicle 41 is given a torque command value for outputting the required torque, and the actual vehicle 41 operates to output the required torque. Here, the actual vehicle 41 includes a power unit, a power train, and a motor ECU. Further, a disturbance component 42 including torque pulsation, mount resonance and the like accompanying the operation of the power unit is added to the actual vehicle 41.
[0031]
Therefore, the disturbance component 42 is added to the motor rotation speed output from the actual vehicle 41 and generally does not match the required torque. In detecting the estimated driving torque, it is conceivable to detect the output torque directly from the actual vehicle 41, but in reality it is difficult to detect the output torque directly. Therefore, the rotational speed of the motor is detected, and the estimated driving torque is calculated from the detected rotational speed using the target inverse model (estimating means). Note that the rotational speed of the motor is usually detected by using a rotational speed detector 43 provided in the motor. In calculating the estimated driving torque, for example, any parameter that correlates with the motor speed, such as the frequency of the motor current, can be used instead of the motor speed.
[0032]
The target inverse model 44 is an inverse model of a model showing target characteristics of power unit, power train, and motor ECU delay, and is preferably an inverse model of a single inertia model that does not include a vibration system. Therefore, it is not an inverse model of the model that strictly indicates the characteristics of the actual vehicle 41 (that is, the dynamic characteristics of the power unit, power train, and motor ECU). This is because in the embodiment of the present invention, the model difference between the actual vehicle 41 and the model is also captured as part of the disturbance element, so that the model difference is eliminated by feedback control.
[0033]
In identifying the model, as shown in FIGS. 4 and 5, the relationship F (force) = vehicle mass × acceleration in the translational motion system is expressed as T (torque) = inertia × angular acceleration (dω / in the rotational motion system). It was identified by applying the similarity to the relationship dt). That is, in order to calculate the estimated driving torque, it is necessary to determine the apparent vehicle inertia, but it is generally very difficult to directly determine the vehicle inertia. Specifically, in order to facilitate measurement, F is constant, the speed v is on the vertical axis, and the time t is on the horizontal axis, so that the time change of the speed v, that is, the acceleration α is constant. And measure. When this relationship is applied to a rotational drive system, the torque T is constant for easy measurement, the rotational angular velocity ω is plotted on the vertical axis, and the time t is plotted on the horizontal axis. Seek change. Vehicle inertia I was obtained from the relationship between the obtained rotational angular velocity ω and time, that is, the slope of the approximate straight line of the plot data. Then, the detected rotational speed is input to the inverse model of the model having the vehicle inertia, and the estimated driving torque to be output is calculated.
[0034]
The comparator 45 and the amplifier 47 in FIG. 3 constitute torque compensation means.
The comparator 45 compares the estimated drive torque obtained by calculation with the torque command value. The comparison difference obtained as a result of the comparison is treated as an estimated disturbance torque and model difference caused by the disturbance. The filter 46 coupled to the comparator 45 is, for example, a low-pass filter, and is arranged to stabilize the control in consideration that the obtained estimated disturbance torque is a differential component and is vulnerable to noise. Yes.
[0035]
The amplifier 47 multiplies the estimated disturbance torque that has passed through the filter 46 by a gain K and outputs a control torque. Here, the gain K is obtained based on the ratio of the power train mass to the vehicle mass (less than 1). This gain K is normally applied to suppress the phenomenon that when the motor of the power unit is driven based on the torque command value, the power train starts to move first due to the driving force and the power unit starts moving due to the reaction force. . That is, this phenomenon is caused by the fact that the torque command value with the vehicle mass in mind first affects the power train having a mass lighter than the vehicle mass. Therefore, it is intended to reduce the estimated disturbance torque and suppress the influence on the power train. The control torque output from the amplifier 47 is added to the required torque, and a torque command value is calculated and reflected in the next control.
[0036]
Next, processing for realizing the control system shown in FIG. 3 will be described with reference to a flowchart shown in FIG. This process is executed by the CPU 17 in the control unit 16. When the required torque is applied to the actual vehicle 41, the motor rotates in response thereto, and the rotational speed is detected by the rotational speed detector 43 in step S100. In step S110, an estimated driving torque is calculated from the rotational speed detected using the target inverse model 44. Subsequently, in step S120, the estimated driving torque is compared with the torque command value, and the comparison difference is extracted as the disturbance estimated torque. In the first routine, the torque command value means the required torque obtained from the accelerator opening and the vehicle speed, and in the first and subsequent routines, the torque command value is obtained by adding the control torque to the required torque.
[0037]
The estimated disturbance torque obtained in step S120 is applied to the filter 46 in step S130 to improve the stability. The estimated disturbance torque that has passed through the filter 46 is multiplied by the gain K obtained as described above in step S140, and the control torque is calculated. In step S150, the final torque command value is obtained by increasing / decreasing the required torque with the obtained control torque, and is given to the actual vehicle 41. One routine is completed by the above steps. This flowchart is repeatedly executed at appropriate intervals.
[0038]
A significant vibration of a power unit or the like in a vehicle usually appears during a sudden accelerator operation, that is, during a sudden change in driving torque. Therefore, the effect of the control during the sudden accelerator operation will be described by comparing a comparative example that is an experimental example not involving the control with Example 1 that is an experimental example involving the control. FIG. 7 is a graph showing experimental results of the comparative example, where the vertical axis represents the motor rotation speed, the torque command value for the motor, and the accelerator opening, and the horizontal axis represents time. FIG. 8 is a graph showing the experimental results of Example 1. The vertical axis represents the motor rotation speed, the torque command value for the motor, and the accelerator opening, and the horizontal axis represents time.
[0039]
In Comparative Example 1, the torque command value for the electric motor follows the accelerator opening (accelerator depression amount), and the torque command value also becomes constant after about 0.1 seconds when the accelerator opening becomes constant. Yes. And the fluctuation | variation (namely, vibration) of the rotation speed of an electric motor has not converged even after about 1 second progress.
[0040]
On the other hand, in Example 1 accompanied by the control according to the embodiment of the present invention, the torque command value fluctuates even after the accelerator opening becomes constant after about 0.1 second. More appropriately, the torque command value varies so as to have a peak opposite to the peak of the motor rotational speed so as to cancel the peak of the motor rotational speed. As a result, the fluctuation peak of the motor rotation speed is suppressed over the entire area, and the fluctuation of the motor rotation speed is almost converged after about 0.4 seconds. In addition, it is understood that the arrival time equivalent to the arrival time to the predetermined torque (rotation speed) in the comparative example is realized, and that the vehicle quickly responds to the accelerator opening (the driver's acceleration request). .
[0041]
Therefore, the power control apparatus according to the embodiment of the first invention can effectively suppress the vibration of the power unit and control the drive torque at high speed.
[0042]
Second embodiment of the invention:
In the embodiment of the first invention, the fluctuation (that is, vibration) of the motor rotation speed after the feedback control action is effectively suppressed. However, since the feedback control does not sufficiently operate in the very initial period immediately after the sudden torque change point (a period of up to about 0.5 seconds), the fluctuation peak of the motor rotation speed still exists although it is suppressed.
[0043]
Here, the fluctuation of the motor rotation speed (vibration of the power unit) is caused by a sudden torque fluctuation caused by a sudden accelerator operation or the like as described above. In a two-inertia system consisting of large inertia and small inertia, vibration immediately after a sudden torque change causes the drive torque for large inertia (ie, vehicle) to drive the small inertia (ie, power train, power output mechanism) first. This is largely due to the phenomenon that occurs.
[0044]
Considering such characteristics, in the second embodiment of the present invention, a pre-processing filter 50 for suppressing fluctuations in required torque is further added.
[0045]
An embodiment of the present invention will be described in detail with reference to FIG. FIG. 9 shows a control system block diagram according to the embodiment of the second invention. In FIG. 9, the constituent elements other than the preprocessing filter 50 have the same functions as the constituent elements in the embodiment of the first invention shown in FIG. To do.
[0046]
The preprocessing filter 50 has the characteristics shown in FIG. In other words, considering the difference between the inertia (mass) of the vehicle and the inertia (mass) of the power train, the time change of the output with respect to the initial input is made slow, while the time change of the output with respect to the input after the initial input is sharpened. It is a characteristic to do. For example, the characteristics of a quadratic function curve and the characteristics of an exponential function curve may be used. More specifically, for example, d _n = D _n-1 + A, T _On = T _On-1 + D _n , T _O0 = 0, d ₀ = A, T _0n ≫T _lim → T _n0 = T _lim It is a characteristic that satisfies the relational expression of By having such characteristics, high responsiveness that promptly realizes the required torque is ensured while suppressing rapid fluctuations in the required torque.
[0047]
Next, processing for realizing the control system shown in FIG. 9 will be described with reference to the flowchart shown in FIG. FIG. 10 shows only step S145 added in association with the addition of the preprocessing filter 50 and steps S140 and S150 which are steps before and after that, and the description and illustration of the remaining steps are omitted.
The required torque calculated based on the accelerator depression amount and the vehicle speed is passed through the preprocessing filter 50, thereby giving the characteristic of suppressing the initial fluctuation caused by the mass difference between the vehicle mass and the power train mass (step). S145). Then, the torque command value is obtained by adjusting the required torque having such characteristics by the control torque (step S150). The obtained torque command value is given to the actual vehicle 41.
[0048]
This is different from the first-order lag low-pass filter 51 having the characteristics shown in FIG. That is, with the characteristics shown in FIG. 12, the initial fluctuation of the input cannot be effectively suppressed, and since it takes a relatively long time to achieve the required output, the required torque changes from moment to moment. That is, it is not suitable for power control in a vehicle in which the target reaching point changes.
[0049]
The effect of the control will be described with reference to Example 2, which is an experimental example involving the control. FIG. 13 is a graph showing the experimental results of Example 2, in which the vertical axis represents the motor speed, the torque command value for the motor, and the accelerator opening, and the horizontal axis represents time.
[0050]
In the second embodiment, compared to the comparative example and the first embodiment, the fluctuation of the torque command value with respect to the accelerator opening is remarkably suppressed. That is, the sudden rise of the torque command value near about 0.2 seconds disappears, and the peak around about 0.3 seconds is greatly suppressed. Further, fluctuations in the motor rotation speed are effectively suppressed over the entire period after about 0.3 seconds.
[0051]
Even in Example 2, there is a first peak in the vicinity of about 0.2 seconds, but this peak appears with or close to the accelerator operation, so it is not felt as an unpleasant vibration. On the other hand, the second peak in the vicinity of about 0.3 seconds is a peak that prevents an increase in torque, so that it is felt as an unpleasant vibration. Further, the time required to reach the predetermined torque (rotation speed) is not changed as compared with the comparative example and the first embodiment. Therefore, in the second example that effectively suppresses the second peak, that is, the power control device according to the embodiment of the second invention, the desired required torque can be obtained without giving an unpleasant vibration to the driver or the like. It is understood that this can be achieved quickly. The first peak is unavoidable due to the structure.
[0052]
Embodiment of the third invention:
Embodiments of the first and second inventions suppress vibration due to disturbance using an inverse model. Since the inverse model includes a differential element, it is known that the system is likely to be unstable due to the influence of noise or the like. Therefore, as illustrated in FIG. 14, it is conceivable to suppress vibration using a normal model 60 instead of the inverse model.
[0053]
In the example illustrated in FIG. 14, the estimated rotational speed of the motor is calculated from the torque command value by the positive model 60 and compared with the detected rotational speed of the motor. The comparison difference obtained as a comparison result indicates a rotational speed variation caused by a disturbance element and does not include a differential element. Therefore, although the filter 46 is arranged in the illustrated example, sufficient stability can be ensured without using the filter 46. The rotation speed difference that has passed through the filter 66 is multiplied by a predetermined gain K in the amplifier 47, converted into a torque dimension, and output as a control torque. A torque command value is obtained by increasing or decreasing the required torque by this control torque.
[0054]
Fourth embodiment of the invention:
In the embodiments of the inventions described above, examples of vehicles having an electric motor as a power unit have been described. However, the embodiments of the inventions described above are for so-called hybrid type vehicles having an electric motor and an internal combustion engine as power units. However, the same applies.
[0055]
Here, it is generally known that the vibration generated with the operation of the internal combustion engine is larger than the vibration generated with the operation of the motor. Therefore, when the internal combustion engine is mounted on the chassis, a mount having a relatively soft characteristic is used to absorb vibration. On the other hand, in a vehicle having only a motor, since it is generally unnecessary to absorb vibration by the mount, a mount having a relatively hard characteristic is used to support the motor in response to a large rising torque. .
[0056]
Therefore, in a hybrid vehicle including a motor and an internal combustion engine as a power unit, vibration accompanying torque fluctuation of a large motor torque is likely to occur compared to a vehicle including only a motor as a power unit. In particular, in the so-called parallel type hybrid vehicle shown in FIG. 15, since the power unit 70 in which the internal combustion engine 71 and the motor 72 are integrated is mounted on the chassis 73, appropriate mounts are used for the internal combustion engine 71 and the motor 72, respectively. I can't. Therefore, in the parallel type hybrid vehicle, the effect brought about by the control device according to the present invention can be more remarkable as compared with the case where the control device according to the present invention is applied to a vehicle having only a motor as a power unit.
[0057]
In the schematic diagram illustrated in FIG. 15, the power unit 70 is swingably coupled to the chassis 73 via a mount 74 schematically represented in a spring form. The output shaft 75 of the power unit 70 is coupled to one end of a drive shaft 76 that represents the power train, and the torsion of the drive shaft 76 is represented by a torsion spring. The other end of the drive shaft 76 is coupled to a wheel 77 that acts as load inertia.
[0058]
The drive torque output from the power unit 70 to the drive shaft 76 via the output shaft 75 can be generated by both the motor 72 and the internal combustion engine 71 based on the torque command value. Therefore, if strict optimum control is to be performed, it is preferable to perform control in consideration of torque fluctuations of the internal combustion engine 71. However, the sudden torque fluctuation of the internal combustion engine 71 is moderate as compared with the sudden torque fluctuation of the motor 72, and the vibration generated in the power unit 70 due to the sudden torque fluctuation is usually caused by the torque fluctuation of the motor 72. In addition, since vibration caused by torque fluctuation of the internal combustion engine 71 is also transmitted to the motor stator 79 and the motor rotor 78, the power unit 70 is appropriately controlled by regarding the vibration caused by the internal combustion engine 71 as disturbance and appropriately controlling the motor 72. Overall vibration is effectively suppressed. Therefore, the above embodiments of the present invention can be applied to a parallel hybrid vehicle as it is.
[0059]
On the other hand, in a so-called series type hybrid vehicle, the internal combustion engine and the motor can be independently mounted on the chassis, so that the internal combustion engine and the motor are respectively connected to the chassis via mounts having appropriate characteristics. Can be mounted. Further, since all the driving torque output to the power train is output by the motor, FIG. 2 can be applied as a schematic diagram thereof, and the embodiments of the above inventions can be applied as they are.
[0060]
The power control apparatus according to the present invention has been described based on some embodiments of the present invention. However, the above-described embodiments of the present invention are for facilitating the understanding of the present invention. It is not intended to limit. It should be understood that the present invention can be changed and improved without departing from the spirit and scope of the appended claims, and that the present invention can include equivalents thereof.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a vehicle including a motor in a power unit to which the present invention can be applied.
FIG. 2 is a schematic diagram schematically showing a vibration system used in the embodiment of the present invention.
FIG. 3 is a block diagram of a control system according to the embodiment of the first invention.
FIG. 4 is a graph used for explaining model identification;
FIG. 5 is a graph used for explaining model identification;
6 is a flowchart showing processing for realizing the control system shown in FIG. 3. FIG.
FIG. 7 is a graph showing experimental results of a comparative example.
8 is a graph showing experimental results of Example 1. FIG.
FIG. 9 is a block diagram of a control system according to an embodiment of the second invention.
FIG. 10 is a flowchart showing processing for realizing the control system shown in FIG. 9;
FIG. 11 is an explanatory diagram illustrating characteristics of a preprocessing filter.
FIG. 12 is an explanatory diagram showing characteristics of a conventional first-order lag low-pass filter.
13 is a graph showing experimental results of Example 2. FIG.
FIG. 14 is a block diagram of a control system according to an embodiment of the third invention.
FIG. 15 is a schematic diagram schematically showing a vibration system used in the embodiment of the fourth invention.
[Explanation of symbols]
10 ... Vehicle
11 ... Motor
12 ... Powertrain
13a, 13b ... wheels
14 ... Inverter
15 ... Battery
16 ... Control unit
17 ... CPU
18 ... ROM
19 ... RAM
20 Accelerator position sensor
21 ... Vehicle speed sensor
30 ... Power unit
31 ... Mount
32 ... Chassis
33 ... Output shaft,
34 ... Drive shaft
35 ... wheel
36 ... Motor rotor
37 ... Stator
40 ... Required torque calculator
41 ... Actual car
42 ... Disturbance component
43 ... Rotation speed detector
44 ... Target reverse model
45 ... Comparator
46 ... Filter
47 ... Amplifier
50 ... Pre-processing filter
51 ... Conventional filter
60 ... Positive model

Claims (6)

In a vehicle having at least one actuator and including a power output mechanism capable of outputting a required torque from the actuator via a drive shaft, the power output mechanism is a control target, and the output of the power output mechanism is the required torque. A control device for giving a torque command value to the actuator so as to control the power output mechanism,
Detecting means for detecting a parameter correlated with the torque output by the actuator;
Estimating means for estimating a torque output from the power output mechanism as an estimated drive torque from the detected parameter using a target inverse model of the power output mechanism;
Torque compensation means for compensating the torque command value so that the torque command value matches the estimated driving torque,
Disturbance torque estimating means for estimating a deviation between the estimated driving torque and the torque command value as a disturbance torque;
A control torque calculating means for multiplying the estimated disturbance torque by a gain that is a value determined based on a ratio of the mass of the power output mechanism and the mass of the vehicle, and obtaining as a control torque;
A control device comprising: a torque compensation means having a torque command value calculation means for compensating the torque command value from the obtained control torque and a required torque for the power output mechanism. In a vehicle having at least a motor and an internal combustion engine and having a power output mechanism capable of outputting a required torque from the motor via a drive shaft, the control device is a control device that controls the power output mechanism. ,
Requested torque calculating means for calculating the required torque based on at least the accelerator opening and the vehicle speed;
A rotational speed detection means for detecting the rotational speed of the electric motor;
Estimating means for estimating the torque output from the power output mechanism as an estimated drive torque from the detected rotational speed using a target inverse model of the power output mechanism;
Torque compensation means for compensating a torque command value given to the power output mechanism based on the estimated drive torque so that the output of the power output mechanism becomes the required torque;
Disturbance torque estimating means for estimating a deviation between the estimated driving torque and the torque command value as a disturbance torque;
A control torque calculating means for multiplying the estimated disturbance torque by a gain that is a value determined based on a ratio of the mass of the power output mechanism and the mass of the vehicle, and obtaining as a control torque;
Torque compensation means having torque command value calculation means for compensating the torque command value from the obtained control torque and the required torque for the power output mechanism;
A control device comprising: In the control device according to claim 1 or 2 ,
The control device, wherein the target model of the power output mechanism is a single inertia model not including a vibration system. A vehicle comprising the control device according to any one of claims 1 to 3 . In a vehicle having at least one actuator and including a power output mechanism capable of outputting a required torque from the actuator via a drive shaft, the power output mechanism is a control target, and the output of the power output mechanism is the required torque. A control method for giving a torque command value to the actuator so as to control the power output mechanism,
Detecting a parameter correlated with the torque output by the actuator;
From the detected parameter, using the target inverse model of the power output mechanism, the torque output by the power output mechanism is estimated as an estimated drive torque,
A deviation between the estimated driving torque and the torque command value is estimated as a disturbance torque,
Multiplying the estimated disturbance torque by a gain that is a value determined based on the ratio of the mass of the power output mechanism and the mass of the vehicle, to obtain a control torque,
A control method that compensates for the torque command value from the calculated control torque and a required torque for the power output mechanism, and matches the torque command value with the estimated drive torque. In a vehicle having at least an electric motor and an internal combustion engine and having a power output mechanism capable of outputting a required torque from the electric motor via a drive shaft, the power output mechanism is a control target, and the control method performs the control. ,
Based on at least the accelerator opening and the vehicle speed, the required torque is calculated,
Detecting the rotation speed of the motor;
From the detected number of revolutions, using the target inverse model of the power output mechanism, the torque output by the power output mechanism is estimated as an estimated drive torque,
A deviation between the estimated driving torque and the torque command value is estimated as a disturbance torque,
Multiplying the estimated disturbance torque by a gain that is a value determined based on the ratio of the mass of the power output mechanism and the mass of the vehicle, to obtain a control torque,
Compensating a torque command value given to the power output mechanism from the calculated control torque and the required torque for the power output mechanism, and setting the output of the power output mechanism as the required torque,
Control method.

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