JPH09294307A - Driving controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize desired operation of a controller and improve control on each engine in a hybrid system made up of rotating force by an internal combustion engine and a motor, by detecting or estimating torque having an influence on the engine and compensating the torque previously. SOLUTION: Torque Tin from a hybrid engine is applied to a second motor 1202 through a differential gear 1203. Then, a torque T2 as a desired output torque Tout can be obtained when a difference between a torque command (command value T2) and the torque Tin applied to the second motor 1202 in the hybrid engine is instructed by a controller 220.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power source control device for a vehicle, and in particular, a hybrid in which an internal combustion engine and a motor exert rotational forces on each other and are mounted as power sources for driving wheels of an automobile. Type drive control device

[0002]

2. Description of the Related Art Conventionally, an internal combustion engine (hereinafter referred to as an engine)
There have been proposed various hybrid vehicles which are equipped with a motor and a motor, and drive both of them together or selectively as a power source of the vehicle (for example, JP-A-7-135701). In the system of this publication, the engine and the first
Motor, a second motor having two shafts, a first differential gear, a second differential gear, and a driving tire.

Torques of the engine and the first motor are applied to the second motor through the first differential gear. Below, the combination of this engine, the first motor, and the operating gear is called a hybrid engine. The second motor is characterized by a structure in which the motor shaft projects in both directions. The second differential gear distributes torque to the left and right wheels to drive the vehicle. In this hybrid system, the driving force of the vehicle is obtained by the hybrid engine and the second motor.

[0004]

However, in the above-described drive control device, the torque of the hybrid engine and the torque of the second motor interact with each other, so that the following inconvenience occurs. In this drive control device, the driver requests the output torque to the vehicle by the accelerator pedal. However, if the second motor torque is controlled according to this torque request value, the torque applied from the hybrid engine to the second motor becomes the first torque. In addition to the output torque of the second motor, torque exceeding the command value is applied to the vehicle. Further, when the required torque is distributed to the hybrid engine and the second motor, the mechanical torque change of the hybrid engine is slow with respect to the electric torque change of the second motor. Will not be obtained.

Further, in the conventionally used rotational speed feedback control, the disturbance torque is mainly friction,
This friction torque is smaller than the torque generated by the second motor to be controlled, and this disturbance torque causes no practical problem in feedback control. However, in this drive control device, the magnitude of the torque applied from the hybrid engine to the second motor has a magnitude that drives the vehicle. Since this value is of the same level as the second motor torque to be controlled, a large disturbance torque is equivalently applied to the rotation speed control system. When such a large disturbance torque is present, if the feedback control gain of the controller is increased in order to improve the followability of the rotation speed control of the second motor, the control system becomes unstable due to the influence of the disturbance torque, and conversely. If the gain is lowered to stabilize the control system, the error between the rotation speed command value and the actual value becomes large, and the controllability deteriorates.

As described above, in the above vehicle drive device,
Since the torque application amount from the hybrid engine to the second motor is large, the controllability of the second motor deteriorates. Therefore, in the present invention, in a hybrid system having a hybrid engine and a second motor,
It is an object of the present invention to improve controllability of a hybrid system by compensating torques that influence each other in order to improve individual controllability.

[0007]

In order to achieve the above object, the present invention provides a hybrid engine composed of an internal combustion engine and a first motor, and an output shaft of the hybrid engine. In a drive control device in which an input shaft of a second motor having two input and output shafts is connected, and an output shaft of the second motor is connected to drive wheels via a differential gear, A torque command value is input or calculated, a torque value applied to the input shaft of the second motor from the hybrid engine is obtained, and the torque command value of the second motor is corrected in a feedforward manner based on this value. By doing so, the controllability of the second motor can be improved.

According to a second aspect of the present invention, the torque command value of the second motor is determined based on a signal based on the operation amount of the accelerator pedal. When the torque amount applied from the hybrid engine to the second motor is corrected by the control described in claim 1 with respect to this command value, the torque commanded by the accelerator pedal is applied to the vehicle. Feeling is improved.

According to the third aspect of the present invention, the torque command value of the second motor is determined based on the command value and the detected value of the output shaft rotation speed of the second motor. By correcting the torque value applied from the hybrid engine to the second motor by the method described in claim 1 with respect to this command value, the responsiveness and stability in controlling the rotation speed of the second motor are improved. To do.

According to a fourth aspect of the present invention, the torque command value of the second motor is determined based on the command value and the detected value of the output shaft rotational position of the second motor. By correcting the torque value applied from the hybrid engine to the second motor by the method described in claim 1 with respect to this command value, responsiveness and stability in controlling the rotational position of the second motor are improved. To do.

According to a fifth aspect of the present invention, the torque input from the hybrid engine to the input shaft of the second motor is calculated from the input value such as the current command value of the second motor and the output value such as the change in rotation speed. Estimate using the disturbance observer of the prior art.
This estimation predicts the motor output value from the motor input value and its transfer function, and the difference between this output predicted value and the actually measured value is due to the torque component externally applied to the system. It is a technology to consider. With this method, the torque applied to the second motor can be estimated, and the torque command value can be corrected based on this estimated value.

The invention described in claim 6 is a method for calculating a torque value applied to an input shaft of a second motor. The engine torque and the torque of the first motor are estimated, and the applied torque is calculated using the specifications of the differential gear. In this case, when the control device for the engine and the first motor measures or estimates the respective output torques, it is possible to substitute the values.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Next, a first embodiment of the present invention will be described. Since the power source of this embodiment is composed of the engine and the motor, the vehicle is a hybrid vehicle. Further, the motor described here means a rotating electric machine that performs both driving and generating functions.

FIG. 1 shows the overall construction of the hybrid vehicle in the first embodiment. In FIG. 1, reference numeral 1204 denotes an engine, which is a known in-line four-cylinder engine that uses gasoline as fuel in this embodiment. The first differential gear 1203 is a known planetary gear having three shafts, and each shaft is connected to the engine 1204, the first motor 1201, and the second motor 1202. The first motor 1201 is
It is a known permanent magnet type three-phase synchronous motor and is vector-controlled by an inverter not described here. The second motor 1202 is a known permanent magnet type three-phase synchronous motor, and as shown in FIG. 2, a shaft 601 connected to a rotor 604 having N and S poles of a permanent magnet,
602 has a structure extending in both directions in the axial direction of the rotor 604, and the current of the winding 603 is vector-controlled by an inverter not shown here.

A rotor position detector (not shown), for example, a known resolver is used for the first motor 1201 and the second motor 1202, and a rotor position signal is output and used for the above-mentioned vector control. To be The second differential gear 1205 connects the shaft 602 of the second motor 1202 and the left and right wheels 1206. Here, the first motor 1
201 controls the rotation speed of the shaft connected to the first motor 1201, so that even if the shaft rotation speed of the second motor 1202, that is, the vehicle speed changes, the engine 1 is independent of this change.
The operation of controlling the rotation speed of 204 to a desired value is performed. First
The method of controlling the motor 1201 is omitted.

The second motor 1202 is the second motor 1
The shaft torque of 202 is controlled. This torque command value is set so that during normal traveling of the hybrid vehicle, the torque commanded by the driver through the accelerator is output to the shaft 602 of the motor 1202 in 202 via the controller in 220. In this case, as shown in FIG. 11, even if an attempt is made to control the second motor 1202 with the torque command value T2, the torque T from the hybrid engine is output at 201.
Since in is applied, the output torque To in the actual vehicle To
ut does not reach the desired value T2.

Therefore, since the torque Tin is applied from the hybrid engine to the second motor 1202 via the first differential gear 1203, the torque command (command value T2) by the accelerator is generated as shown in FIG. And the second motor 1
Torque Tin applied from the hybrid engine to 202
If the controller 220 issues a command to the difference between and, the torque T2 can be obtained as the desired output torque Tout for the vehicle.

The control at this time will be described with reference to the flowchart shown in FIG. In step 501,
After inputting the torque command value T2, the torque Tin acting from the hybrid engine is input to the controller 220 in step 502. Then, in step 503,
In the command torque correction unit, the torque command value T2 is subtractively corrected by the torque Tin acting from the hybrid engine.
Although the torque command value of the second motor is obtained from the accelerator command here, it is also possible to determine the torque command value from the states of the accelerator command and the brake command.

As an application of this embodiment, there is an application in which the engine torque output Tin of the hybrid engine is stopped by fuel cut or the like during traveling. Although a sudden torque loss is felt when the fuel is cut, it is possible to reduce the torque loss by compensating for this torque reduction amount with the torque of the second motor 1202. further,
The first motor 1201 of the hybrid engine drives the engine 1
It is also applicable when starting 204. In this case, the second motor 1202 is compensated by compensating the torque generated by the second motor 1202 according to the torque Tin input from the hybrid engine to the second motor 1202.
It is possible to suppress the change in the output torque of the. By this control, for example, the vehicle does not move even when the engine is started when the vehicle is stopped, and the torque shock does not occur when the engine is started when the vehicle is propelled.

For the torque value input from the hybrid engine to the second motor 1202, the engine torque is estimated from the operating state of the engine (rotation speed, throttle opening, air amount, fuel injection amount, etc.) The torque of the first motor 1201 is estimated from the command torque of the motor 1201 or the current / voltage of the first motor 1201, and is calculated from the engine torque and the torque of the first motor 1201 in consideration of the gear ratio of the operating gear 1. To do. In this calculation, when the control device of the engine and the first motor 1201 estimates or measures the respective torques, it is possible to perform the calculation based on the values. As another method of obtaining the torque input to the second motor 1202, the input shaft torque can be directly measured by a torque sensor or the like. Since the torque value input to the second motor 1202 is known as described above, it is possible to compensate the torque command value of the second motor 1202 based on this value.

With the above means, the output torque can be controlled according to the accelerator operation amount, and the operation feeling of the hybrid vehicle can be improved. The above control method can also be applied when the torque command value of the second motor is given from another control device. In the control system of the hybrid system, first, the torque value applied from the hybrid engine to the input shaft of the second motor 1202 is fetched. This torque value is a torque measurement value using a torque sensor or the like, or the first motor 12
01 and the input / output torque of the engine 1204 (measured or estimated) and the estimated value of the torque applied to the second motor 1202 from the specifications of the first differential gear 1203.

The torque command value of the second motor 1202 is
A value obtained by converting the accelerator command into a torque command value or a value determined by feedback control of PI, PID or the like based on the deviation of the rotational speed or the rotational position is used. The present invention is characterized in that the determined torque command value is corrected in a feedforward manner based on the torque value applied from the hybrid engine to the second motor 1202.

By this feedforward control, the second
In the control of the motor 1202, it is possible to previously correct the amount of torque applied to the second motor 1202 from the hybrid engine, which was conventionally treated as a disturbance. As a result, the change in the torque input from the hybrid engine does not act as a disturbance, and the second motor 1
It is possible to improve the controllability of 202, and thus the controllability of the entire hybrid system.

Next, a second embodiment of the present invention will be described. The overall structure of the hybrid vehicle of the second embodiment is the first
Since the contents are the same as those in FIG. 1 in the embodiment, the control part different from the first embodiment will be described below. The purpose of controlling the second motor 1202 in this embodiment is to control the rotation speed or rotation angle of the second motor 1202 to a desired value. For example, in FIG. 1, when the engine 1204 is started by the first motor 1201, the rotation speed of the second motor 1202 is controlled to 0 so that the vehicle does not move, or the rotation position is fixed to an arbitrary value. Used for such control. In addition, the controllability is improved even when the vehicle is driven at the commanded speed.

First, the case of controlling the rotation speed of the second motor 1202 will be described with reference to FIG. The torque Tin input from the hybrid engine in 201 to the second motor 1202 is
In the rotational speed control system of 202, it acts as a disturbance and causes deterioration of rotational speed controllability. That is, when torque is input from the hybrid engine to the second motor 1202, the rotation speed of the second motor 1202 increases, and conversely, when the torque is absorbed, the rotation speed decreases. In the conventional technique, a rotation speed feedback control system is configured to control the rotation speed to a desired rotation speed. However, when the input torque component from the outside is large, this disturbance torque cannot be completely compensated by only feedback. In other words, increasing the feedback gain makes the system more likely to oscillate,
When the feedback gain is reduced, the error between the rotation speed command value and the actual value increases. Therefore, in the present invention,
Focusing on the fact that the input torque to the second motor 1202 can be estimated or measured as shown in the first embodiment, means for improving the rotational speed controllability by providing feedforward compensation for this torque in advance is provided. A flowchart of this control is shown in FIG. First, in step 101, the rotation speed command value w2 is input, and then in step 102, the actual value of the rotation speed is measured. Then, in step 103, the torque value Tin input to the second motor 1202 from the hybrid engine is fetched,
Next, in step 104, the torque command value of the second motor 1202 is calculated by PI or PID control based on the difference between the rotation speed command value and the actually measured value, and the second command is calculated from this value.
The motor 1202 is corrected by subtracting the torque applied from the hybrid engine.

Here, an engine starting method using the control of this patent will be described. First, the rotation speed feedback control is performed by the second motor 1202 so that the rotation speed of the shaft becomes zero. Then, in this state, the first motor is used as a starter to start the engine.
Then, the vehicle does not move, and stable starting operation becomes possible.

In addition, the present method can be applied to the case where the vehicle speed is controlled to a desired value by the automatic driving of the vehicle, and the output of the second motor 1202 is always output even when the engine of the hybrid engine is started or stopped. Axial torque can be kept constant and good controllability can be obtained. Further, during the rotation angle control, similarly to the rotation speed control, the rotation angle controllability can be improved by compensating the torque input to the motor 1202 from another engine in advance. FIG. 7 shows a control configuration of the present invention at the time of controlling the rotation angle, and FIG. The difference between the rotation speed control and this rotation angle control is
Since the control target is only the change based on the change of the rotation speed w of the second motor 1202 to the rotation angle θ, the detailed description will be omitted.

Further, a third embodiment of the present invention will be described. When the torque input from the hybrid engine cannot be estimated as in the first and second embodiments, the torque control system uses the disturbance torque applied to the input shaft of the second motor 1202 as shown in FIG. It is also possible to compensate using the observer. This observer estimates a torque component that causes disturbance from a transfer function indicating the relationship between the torque command value of the second motor 1202, the actual rotation angle of the output shaft, and this input / output value. Here, the torque of the second motor 1202, the command value, and the actual rotation angle are selected as the inputs of the observer. However, since the purpose of this means is to estimate the disturbance torque, the second motor is used as the input of the observer. It is also possible to use other inputs and transfer functions, such as estimating the disturbance torque by using the current of 1202, the actual rotation speed or the actual rotation angle, and using the transfer function indicating the relationship between the current and the rotation speed or the rotation angle. is there.

By this method, the torque applied from the hybrid engine to the second motor 1202 can be estimated, and the controllability can be improved by using this estimated value as in the first and second embodiments. In the above-described embodiment, another effect is a smooth start operation of the engine. When the engine 1204 is started by the first motor 1201 when the vehicle is stopped, the torque applied to the second motor 1202 largely changes before and after the engine starts. Therefore, the second motor 12
It is necessary to control the torque, rotation speed or rotation angle of 02 to prevent torque shock and erroneous start. In this case the second
The control method of this patent is effective for controlling the rotation speed and rotation angle of the motor 1202 of FIG.

As another form of the start operation, the second operation
A method of starting the engine at a certain speed after starting the vehicle with the motor 1202 of FIG. In this case, the torque transmitted to the tires suddenly changes before and after the engine is started, causing unpleasant shocks and sudden changes in the vehicle rotation speed. Patents can be used.

Further, when the engine is stopped due to fuel cut or the like while traveling, a sudden torque loss occurs,
It is possible to prevent this feeling of torque loss by assisting the amount of engine torque loss by the second motor 1202. In addition, when the vehicle speed is controlled to a desired value, the controllability is improved by using this control method.

Although the rotor position detector (not shown) is attached to the motor in the above embodiment, the signal of the rotation detector attached to the engine may be used. Further, in order to simplify the motor structure, it is possible to control the synchronous motor by a known sensorless method without using the rotor position detector. Further, it is possible to use an induction motor or a reluctance motor instead of the synchronous motor. Even when an induction motor or a reluctance motor is used, known sensorless control that does not use a rotor position detector or a rotation speed detector can be applied.

Further, the internal combustion engine of the first embodiment has a series 4
Although a cylinder gasoline engine is used, the number of cylinders is not related to the gist of the present invention. It may also be a diesel engine. In FIG. 1, the engine 1204 and the first motor 1201 are connected to the second motor 1202 via the first differential gear 1203, but the present invention is not limited to the torque input to the second motor 1202. The control amount of the second motor 1202 is corrected based on the value.
Regarding the configuration of the hybrid engine until the torque is input to the engine 02, for example, as shown in FIG.
It is also possible to combine 04 and the motors 1202 and 1207 in series.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a hybrid vehicle according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram showing an outline of a motor having two axes in FIG.

FIG. 3 is a block diagram showing torque control of the first embodiment.

FIG. 4 is a flowchart showing a torque control calculation of the first embodiment.

FIG. 5 is a block diagram showing a rotation speed control of a second embodiment of the present invention.

FIG. 6 is a flowchart showing a calculation of a rotation speed control of the second embodiment.

FIG. 7 is a block diagram showing rotation angle control.

FIG. 8 is a flowchart showing a calculation of rotation angle control.

FIG. 9 is a block diagram showing torque control using an observer according to a third embodiment of the present invention.

FIG. 10 is an overall configuration diagram showing another structure of a hybrid vehicle.

FIG. 11 is a block diagram showing conventional torque control.

[Explanation of symbols]

201 Torque applied from hybrid engine to second motor 202 Second motor 203 Controller 206 Observer 1201 First motor 1202 Second motor 1203 First differential gear 1204 Internal combustion engine 1205 Second differential gear 1206 Tire 1207 motor

Claims (7)

[Claims] 1. A hybrid engine including an internal combustion engine and a first motor, a second motor for increasing / decreasing an output shaft torque of the hybrid engine, and an output shaft of the second motor via a differential gear. A drive control device connected to the drive wheels by controlling the second motor based on a torque command value of the second motor and applying the second engine to the input shaft of the second motor. A drive control device comprising: a torque calculation unit that obtains a torque as an applied torque calculation value; and a correction unit that corrects a torque command value of the second motor based on the applied torque calculation value. 2. The drive control device according to claim 1, wherein the torque command value of the second motor is calculated based on at least a signal linked to an operation amount of an accelerator pedal. 3. The drive control device according to claim 1, wherein the torque command value of the second motor is calculated based on at least the command value and the detected value of the output shaft rotation speed of the second motor. . 4. The drive control according to claim 1, wherein the torque command value of the second motor is calculated based on at least a command value and a detected value of a rotational position of an output shaft of the second motor. apparatus. 5. The torque applied from the hybrid engine to the second motor input shaft is estimated based on at least the output torque value or motor current of the second motor and the rotation speed or rotation angle of the output shaft. The drive control device according to any one of claims 1 to 4, characterized in that: 6. The torque applied from the hybrid engine to the second motor input shaft is calculated from at least the internal combustion engine torque in the hybrid engine and the torque of the first motor. 4. The drive control device according to any one of 4 above. 7. The drive control device according to claim 1, wherein the first motor and the second motor are combined.