JP2713580B2 - Electric vehicle control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to an electric vehicle in which wheels mounted so that output torque and steering angle can be individually controlled are arranged in front, rear, left and right. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control apparatus for an electric vehicle that optimally controls the output torque and the steering angle of an electric wheel that constitutes the wheel based on signals from an accelerator, a brake, a steering wheel and the like.

(Prior Art) In recent years, development and research of electric vehicles have been gradually performed on the background of social demands for easing concentration of energy sources to petroleum and improving energy use efficiency.

By the way, an electric vehicle naturally does not require an air intake for cooling the engine like a conventional gasoline-powered vehicle. If the motor is arranged at an appropriate position, there is a degree of freedom in the external design of the front bonnet portion. Also, since there is no need for a transmission or a muffler, there is no protrusion under the floor or the like. Therefore, not only the air resistance can be extremely reduced, but also the weight and the structure can be simplified. There are various advantages. In addition, since electric vehicles do not emit exhaust gas, they do not emit air pollutants, and there is almost no noise equivalent to exhaust noise, so that they have low noise. Therefore, they also have public benefits of low pollution and low noise. Furthermore, in order to improve driving safety in the future, various devices such as a collision prevention device, a device that automatically stops when a red signal is detected, and a device that automatically runs on a predetermined course, etc. Even if devices that contribute to safe driving of vehicles are developed, electric vehicles that are all electrically controlled also have the advantage that these devices can be controlled easily.

Therefore, today, in places where any of these advantages can be exhibited, electric vehicles are used in some fields on a trial basis or practically in place of conventional internal combustion engines using gasoline. It has become. As the latest electric vehicles currently in use, those of the type shown in FIGS. 17 and 18 in which a motor and a speed reducer are independently connected to the left and right driving wheels of the rear axle, respectively, are known.

As shown in these figures, an electric vehicle of this type has a motor 2 connected to driving wheels via a speed reducer 3.
Are arranged inside the electric vehicle E with its rotation axis and the axle parallel to each other, and the batteries 1 as the power source of the motor 2 are mounted in the front-rear direction of the electric vehicle E as shown in the figure. Further, a control device 4 for controlling the rotation speed of the motor 2 and the running state of the electric vehicle E is provided in the front of the center of the electric vehicle E.

Signals based on the driver's intention are input to the control device 4 from, for example, a steering wheel, an accelerator pedal, a brake pedal, and the like, and the electric vehicle E is controlled based on these signals.
Is controlled.

Among these signals, the signal output from the accelerator pedal is a reference signal when the control device 4 calculates the rotation speed of the motor 2, and the control device 4 approaches the rotation speed calculated based on this signal. Thus, the current flowing from the battery 1 to the motor 2 is controlled. The power generated by the controlled current is transmitted to the tires 5 via the speed reducer 3, and the electric vehicle E runs at an arbitrary speed.

(Problems to be Solved by the Invention) However, in such a conventional electric vehicle, although the electric vehicle has various advantages as described above, the conventional internal combustion engine is simply used as a motor. It is just an electric car that has been replaced, and it is hard to say that it has maximized its benefits.

In other words, the power source is a motor in place of the conventional engine, and the power supplied to this motor is controlled by operating the accelerator pedal. Is what is being done. Therefore, a conventional electric vehicle only controls electric power supply even though its driving source is a motor that can be precisely controlled using a computer, so that it is possible to perform extremely advanced driving control. It can be said that it does not effectively utilize the potential feature of being able to do so. For this reason, it is a matter of course that the energy utilization efficiency is low and the running distance per charge of the battery is short.

The present invention has been made to solve various drawbacks of a conventional electric vehicle, and a wheel itself forms a part of a motor, and electric wheels which are individually steerably mounted are arranged in front, rear, left and right. Another object of the present invention is to provide a control device for an electric vehicle that can individually control the output torque and the steering angle of these electric wheels without a mechanical power transmission mechanism.

[Means for Solving the Problems] According to the present invention for achieving the above object, a rotor is mounted on a wheel on which a tire is mounted, and an axle supporting the wheel cooperates with the rotor. A plurality of electric wheels formed by attaching a stator that rotationally drives the wheels are provided, and in an electric vehicle including a handle for steering the electric wheels, an operation mode selection unit that selects an operation mode of the electric vehicle; When the normal mode is selected by the rotation angle detection means for detecting the rotation angle of the steering wheel and the operation mode selection means, normal traveling is performed based on the rotation angle of the steering wheel detected by the rotation angle detection means. The steering angle of each of the electric wheels is calculated so as to be able to perform the rotation angle detection. Steering angle calculating means for calculating the steering angles of all the motorized wheels in the same direction so as to be able to run obliquely, in accordance with the rotation angle of the steering wheel detected by the means; While setting each steering angle calculated by
When the rotation mode is selected by the operation mode selection means, a steering means for setting all the electric wheels to a steering angle capable of traveling on the same circumference so as to be able to rotate in place is provided. And

(Operation) With this configuration, the steering angle of each electric wheel arranged in the electric vehicle is calculated by the steering angle calculation means in each of the selected driving modes, that is, the normal mode, the skew mode, and the rotation mode. Is set to the specified steering angle.

Specifically, when the normal mode is selected by the driving mode selection unit, the steering angle calculation unit calculates the optimum steering angle of each electric wheel so that normal driving can be performed by operating the steering wheel. I do. For example, if the electric vehicle is traveling completely straight, each motorized wheel will point in the direction of travel of the electric vehicle, while if the steering wheel is turned to the right, the motorized wheels of the front light will be The steering angle and the steering angle of the front left electric wheel and, if necessary, the steering angle of the rear right and rear left electric wheel are calculated individually.

When the skew mode is selected by the driving mode selection means, the steering angle calculation means calculates the steering angles of all the electric wheels in the same direction so that the vehicle can run obliquely according to the rotation angle of the steering wheel. . For example, when the steering wheel is rotated to the right by a small angle, all the electric wheels calculate the rightward steering angle according to the rotation angle of the steering wheel. When the rotation angle of the steering wheel is increased, a steering angle accompanying the rotation angle is calculated.

The steering means sets each electric wheel to the steering angle calculated by the steering angle calculation means. When the rotation mode is selected by the driving mode selection unit, the steering angle calculation unit runs all the electric wheels on the same circumference so that the electric vehicle can rotate on the spot. Set a steering angle that can be used. If the rotation mode is selected,
The steering angle of the motorized wheel is uniquely set regardless of the rotation angle of the steering wheel.

(Embodiment) Hereinafter, a main structure of a steering system and a traveling system of an electric vehicle on which an electric vehicle control device according to the present invention is mounted, and a configuration and operation of the control device will be described in detail with reference to the drawings. I do.

FIG. 1 is a schematic sectional view of an electric vehicle on which the control device for an electric vehicle according to the present invention is mounted.

In the figure, a right wheel portion is schematically illustrated, and a left wheel portion is schematically illustrated. In this figure, the electric vehicle E has four electric wheels
Each of the motorized wheels 20 is provided with a motor 2 on the outer side of a wheel 11 on which the tire 5 is mounted on the outer periphery, and is of a direct drive type. The wheel 20 is attached to the vehicle body 10 via a suspension 13 supporting a hollow knuckle 12 so as to be vertically movable and steerable. Each of the electric wheels 20 is connected to the hollow knuckle 12 by a steering actuator 40 as a steering means for steering the electric wheels 20 by a motor. Therefore, for each of the motorized wheels 20, 20,..., The torque and the steering angle output therefrom can be freely set, and if the output torque and the steering angle of each motorized wheel 20 are appropriately controlled, Various running characteristics can be provided.

As shown in FIG. 2, each electric wheel 20 has a hollow hub 15 coaxially fastened and fixed to a hollow knuckle 12 with a bolt 14 so that the wheel 11 can be rotatably mounted on the hollow hub 15 via a bearing 16. Installed. The hollow hub 15 also serves as the rotating shaft of the motor 2 and the axle, thereby simplifying the structure of the shaft portion.

A rotating wheel 25 is mounted on the outer periphery of the wheel 11, and the rotating wheel 25 is mounted on a rim 19 fixed to the outer periphery of the wheel 11 by a hub bolt 17 and a hub nut 18.
And the tire 5 fitted on the outer periphery of the rim 19.

Further, a rotor 30 of the motor 2 and a cover 21 for covering the outside of the motor 2 are fastened and fixed to the outer peripheral end portion of the wheel 11 from outside by bolts 22.

The rotor 30 includes an annular yoke 23 and this yoke 23
And a rare-earth permanent magnet 24 that generates a strong magnetic field with a thin thickness and is fixed to the inner peripheral surface thereof with an adhesive or bolts.

A stator 35 opposed to the rotor 30 with a small gap G is provided between the inner peripheral portion of the armature core 32 around which the coil 31 is wound and the dust seal member 34 by the bolt 33 to the protrusion 15a of the hollow hub 15. And the torque ring 36.

A flat-plate-like terminal 37 extends between the two, and this terminal 37 is provided to securely connect the coil 31 and a power line 38 inserted through the inner periphery of the hollow hub 15. It was done. The end of the terminal 37 is connected to the coil 31, and the power line 38 is connected to a power control unit of a control device described later. Also, these motorized wheels 2
Although not shown, 0, 20,..., For example, a magnetic pole position detecting element using a Hall element and a temperature of the rotor 30 or the stator 35 for calculating the output torque and the rotation speed of the electric wheel. And a motor temperature detection sensor for detecting the temperature rise of the coil 31 under a high load under high load, from the thermal breakdown of the magnetic pole position detection element and the performance deterioration of the permanent magnet 24. Protection.

Next, FIG. 3 is a schematic perspective view of a steering system controlled by the control device for an electric vehicle according to the present invention.

In the electric vehicle shown in FIG. 1, four electric wheels 20 are mounted on the front, rear, left and right of a vehicle body (not shown).
A steering actuator 40 for adjusting the steering angle according to a command from the control device 100 is attached to each of the hollow knuckles 12 of the electric wheels 20 described above. For this reason, when the steering actuator 40 operates, the electric wheels 20
Thus, the steering angle can be changed, and the steering angle can be freely adjusted for each electric wheel 20.

FIG. 2 shows a schematic perspective view of a steering system controlled by a control device.

A θ-V converter 50 is connected to the control device 100 so that a voltage corresponding to the rotation angle of the steering wheel 45 operated by the driver is output from the θ-V converter 50. Has become. As an example, in order to facilitate understanding, the driving mode is set to a normal mode to be described later (a driving mode in which the driver can move forward or backward according to the driver's intention, as in the case of a conventional automobile) and stop. Considering the case where the driver rotates the steering wheel 45 in the state in which the steering wheel 45 is rotated, the rotation of the steering wheel 45 causes the θ-V converter 50 to
The voltage value output to 0 changes, and the control device 1
00 individually calculates the steering angles of the respective electric wheels 20, 20,... Based on the voltage change, and operates the respective steering actuators 40, 40,. ,... Are set to the calculated steering angles. In this case, the steering angle of each of the electric wheels 20, 20,.
Of course, it is stored in 0.

FIG. 4 shows a schematic configuration diagram around the control device of the electric vehicle according to the present invention.

As shown, the signal output source for outputting a signal for causing the control device 100 to control the running state of the electric vehicle includes a steering wheel 45 and an operation mode of the electric vehicle, for example, normal, parking, neutral, and skew. , An operation mode switching lever 46 for selecting various modes of rotation, an accelerator pedal 47 for outputting a drive signal for the electric vehicle, a brake pedal 48 for outputting a deceleration signal for the electric vehicle, and a traveling of the electric vehicle. There is a forward / reverse switching lever 49 for selecting a direction. Therefore, when the electric vehicle is driven, a desired driving mode is selected by the driving mode switching lever 46, and the traveling direction (in the case where the selected driving mode is the rotation mode) is moved by the forward / reverse switching lever 49. Is the rotation direction.), The vehicle is driven by the handle 45, the accelerator pedal 47 and the brake pedal 48.

An angle sensor (not shown) is attached to the shaft of the handle 45, and a rotary encoder or a potentiometer, for example, is used as the angle sensor. A θ-V converter 50 is connected to this angle sensor, and the θ-V converter 50
From the handle detected by the angle sensor
The voltage V corresponding to the rotation angle θ of 45 is output. The operation mode switching lever 46 is provided with a position sensor (not shown) for detecting a position set by the operation. For example, a limit switch, a proximity switch, or the like is used as the position sensor. ing. And this position sensor has a θ-S converter
The θ-S converter 51 outputs a set position of the operation mode switching lever 46 as a contact signal. That is, the control device 100 detects the operation mode set by the operation mode switching lever 46 based on the contact signal.

And the accelerator pedal 47 and the brake pedal 48
Although not shown, sensors for detecting the amounts of depression of the pedals 47 and 48 are respectively mounted. These sensors are the same as the sensors for detecting the rotation angle of the handle 45, for example, a rotary encoder or the like. Potentiometers and the like are used. Θ-V converters 52 and 53 are connected to these sensors,
Converters 52 and 53 output voltages V corresponding to the amounts of depression of accelerator pedal 47 or brake pedal 48 detected by these sensors, respectively. Further, the forward / backward switching lever 49 includes an operation mode switching lever 46.
Similarly to the above, a position sensor (not shown) for detecting a position set by the operation is provided,
The θ-S converter 54 is connected to this position sensor. The θ-S converter 54 outputs the set position of the forward / reverse switching lever 49 as a contact signal. That is, the control device 100 uses the contact signal to control the forward / reverse switching lever 49.
Will be detected.

The outputs from the θ-V converter 50, the θ-S converters 51 and 54, and the outputs from the θ-V converters 52 and 53 are transmitted to a control device 100 configured as described later to indicate the running state of the electric vehicle. Is input as a command signal for controlling.

The control device 100 is roughly divided into a central processing unit 60 having various arithmetic units described later, and controls the output torque of each of the electric wheels 20, 20,... Based on a command from the central processing unit 60. And a central processing unit 60
And a steering angle control unit 80 for controlling the steering angle of each of the electric wheels 20, 20,.

The central processing unit 60 is provided outside or inside the electric vehicle, for example, a motor current detection sensor,
By inputting detection signals from a sensor group 90 composed of a motor temperature detection sensor, a battery voltage detection sensor, and the like and various error signals detected by the central processing unit 60 itself, and processing these signals, the electric vehicle A traveling permission determining unit 61 for determining whether or not the traveling state is abnormal and detecting the traveling state and displaying the determination result is provided.The processing result of the various signals by the traveling permission determining unit 61, for example, traveling The speed, various warnings, management data of the electric vehicle, and the like are displayed on the display device 95.

In addition, the central processing unit 60 includes a travel management data collection unit.
62 is provided, and the traveling management data collection unit 62 is not directly related to the present invention, and therefore detailed description thereof is omitted.However, as its main function, various functions output from the sensor group 90 described above are provided. The detection signals are collected and stored as data. The stored data can be taken out as needed. The collected data can be used as maintenance information for the electric wheels 20, 20,. It can be used as information such as an operation meter.

Further, the central processing unit 60 includes a reference torque calculating unit 63, 4
A wheel torque ratio calculation unit 64 and each wheel torque calculation unit 65 are provided. The reference torque calculation unit 63 includes θ-V converters 52 and 53.
Calculates a common reference torque for each of the electric wheels 20, 20,... Based on a signal corresponding to the amount of depression of the accelerator pedal 47 and the amount of depression of the brake pedal 48, which are output as voltage values from The four-wheel torque ratio calculation unit 64 includes a selected operation mode of the operation mode switching lever 46 input via the θ-S converter 51 and a handle 45 output as a voltage value from the θ-V converters 50 and 52. Of each electric wheel 2 based on a signal corresponding to the rotation angle of the
0, 20,... Calculate the respective torque ratios.

Then, each wheel torque calculator 65 calculates the torque of each of the electric wheels 20, 20,... And the four-wheel torque ratio calculated by the reference torque calculator 63 and the four-wheel torque ratio calculator 64.
The output torque of each electric wheel 20 is calculated individually, and the calculation result is output to the drive control unit 70. Therefore, each motorized wheel 2
Are driven with a predetermined torque based on the output voltage and output current from the drive control unit 70 connected to each electric wheel 20. The reference torque calculator 63, the four-wheel torque ratio calculator 64, and each wheel torque calculator 65 constitute a torque calculator.

In addition, the central processing unit 60 has four steering angle calculating means.
A four-wheel steering angle calculation unit 66 is provided. The four-wheel steering angle calculation unit 66 includes a setting position of the operation mode switching lever 46 output as a contact signal from the θ-S converter 51 and a θ-V converter.
The steering angle of each of the electric wheels 20, 20,... Is calculated based on a signal corresponding to the rotation angle of the steering wheel 45 output as a voltage value from 50, 52. The calculation result by the four-wheel steering angle calculation unit 66 is output to the steering angle control unit 80, and the respective electric wheels 20, 2
0,... Are individually set to a predetermined steering angle by the steering actuator 40 driven by the steering angle control unit 80.

FIG. 5 is a block diagram of a control unit for an electric vehicle according to the present invention, in particular, a part for controlling rotation of a motorized wheel.

As described above, the electric vehicle E is provided with the steering wheel 45, the driving mode switching lever 46, the accelerator pedal 47, the brake pedal 48, and the forward / reverse switching lever 49 as shown in the drawing. 45 is a θ-V converter
The operation mode switching lever 46 has a θ-S converter 51,
A θ-V converter 52 is connected to the accelerator pedal 47, a θ-V converter 53 is connected to the brake pedal 48, and a θ-S converter 54 is connected to the forward / reverse switching lever 49.

θ-S converter 51, θ-V converter 52 and θ-V converter 53
Is a PID non-linear control section 67 for performing known PID control in a non-linear manner.
The PID nonlinear control section 67 is provided in each wheel torque calculation section 65 shown in FIG. The θ-V converter 50 and the θ-S converter 51
The switching unit 55 is connected to the switching unit 55.
The four-wheel steering angle calculating unit 66, the four-wheel torque ratio calculating unit 64, and the driving mode switching lever 46 are used as the driving modes of the electric vehicle.
When the skew mode is selected by the switch unit 55, when the rotation mode is selected by the skew steering angle calculation unit 81 and the operation mode switching lever 46 selected by the switching unit 55, the switching unit 55
Are connected so that the rotary steering angle tables 68 provided in the central processing unit 60 can be selected. The switching unit 55 includes an operation mode switching lever.
When the normal mode, that is, the mode for normal traveling such as forward or backward, is selected by 46, θ−V
The converter 50 includes a four-wheel steering angle calculator 66 and a four-wheel torque ratio calculator.
When the skew mode is selected, the θ-V converter 50 is connected to the skew steering angle calculation unit.
When the rotation mode is selected, the respective contacts are operated so as to connect the θ-V converter 50 to the rotary steering angle table 68.

The θ-S converter 54 determines the rotation direction of each of the electric wheels 20, 20,... Based on the contact signal output from the θ-S converter 54.
Are connected to a rotation direction determination unit 71 provided in the drive control unit 70, and the rotation direction determination unit 71 rotates the electric wheels 20, 20,. Set.

Further, a four-wheel steering angle calculation unit 66, a skew steering angle calculation unit 81, and a rotation steering angle table 68 are connected to the rotation direction determination unit 71, respectively, and are also connected to a gate control unit 74 described later. , And outputs a signal relating to the rotational direction of each of the electric wheels 20, 20,. The PID nonlinear control section 67 and the four-wheel torque ratio calculation section 64 are connected to a supply voltage control section 72 provided in the drive control section 70, and the supply voltage control section 72 supplies the electric power to the electric wheels 20, 20,. The supply voltage is controlled indirectly.

In addition, a pulse train generating unit 73 is connected to the supply voltage control unit 72 via a gate control unit 74 connected to a power control unit 75 that supplies power to a motor configuring the motorized wheel 20,
The power output to the motorized wheels 20 is controlled based on the pulse output from the pulse train generation unit 73 by the ON time of the gate controlled by the gate control unit 74.

Further, the supply voltage control unit 72 is connected to a tap switching unit 77 that switches a tap included in the battery group 76 that applies a voltage to the power control unit 75, and the switching of the tap is output from the supply voltage control unit 72. The supply voltage signal. When switching this tap,
Although not shown, the operation is performed by a pulse motor, and the pulse motor is operated by a signal output from the tap switching unit 77.

As described above, the motor 2 that constitutes the electric wheel 20 is provided with the magnetic pole position detecting element 85 that outputs a pulse every time the motor 2 rotates by a predetermined angle. The output pulse is connected to the gate control unit 74 and the magnetic pole position detecting element 85.
The signal is output to the F / V converter 86, and provides feedback for rotating the motor 2. In addition, the power control unit 75
A signal processing unit 87 is connected to the F / V converter 86, and the signal processing unit 87 is connected to the PID nonlinear control unit 67 and performs feedback in determining a voltage to be applied to the motor 2.

FIG. 6 is a block diagram showing a part for controlling the steering of the electric wheels in the control apparatus for an electric vehicle according to the present invention.

As described above, the electric vehicle E is provided with the steering wheel 45 and the operation mode switching lever 46 as shown in the drawing, and as described above, the steering wheel 45 is connected to the θ-V converter 50.
However, a θ-S converter 51 is connected to the operation mode switching lever 46. The θ-V converter 50 and the θ-S converter 51 are connected to a switching unit 55. The switching unit 55 includes a four-wheel steering angle calculating unit 66 and a skew steering angle calculating unit 81. And the rotary steering angle table 68 are connected so that they can be selected, and they are also connected to the selection unit 56 that is switched by the θ-S converter 51. The switching units 55 and 56 connect the θ-V converter 50 to the steering angle command unit 82 via the four-wheel steering angle calculation unit 66 when the normal mode is selected by the operation mode switching lever 46. When the contact is activated and the skew mode is selected,
The contact is operated so as to connect the θ-V converter 50 to the steering angle command unit 82 via the skew steering angle calculation unit 81, and when the rotation mode is selected, the θ-V converter 50 is turned off. The respective contacts are operated so as to be connected to the steering angle command section 82 via the rotary steering angle table 68. The steering angle command unit 82 includes:
The steering angle servo 83 that drives the steering actuator 40 described above is connected, and a command related to the steering angle of each of the electric wheels 20, 20,... Is output from the steering angle command unit 82.

The operation of the control device for an electric vehicle according to the present invention thus configured will be described below with reference to the operation flowcharts shown in FIG. 7 and subsequent figures. In addition,
In this description, the operation will be described with reference to FIGS. 1 to 6 as necessary so that the actual operation of the electric wheel can be easily understood.

The flowchart shown in FIG. 7 is a main flowchart of the control device for the electric vehicle according to the present invention. That is, it is a flowchart of a main part for controlling the traveling of the electric vehicle.

Step 1 First, the driver operates the keys to activate the control device 100 that comprehensively controls the operation of the electric vehicle.

Step 2 When the key is turned on, the operation of each IC element provided in the central processing unit 60, that is, the operation of the storage element or input / output element and various conversion elements, the drive control unit 70 connected to the central processing unit 60, and the steering The operations of the angle control unit 80, the sensor group 90, and the display device 95 are all initialized. Since the initialization process is generally performed, a detailed description thereof will be omitted.

Step 3 Next, the control device 100 outputs the position set by the operation mode switching lever 46 as a digital signal as a θ-S converter.
51, steering wheel 45, accelerator pedal 47 and brake pedal 48
Θ-V converters 50, 52, 5 that output voltages corresponding to the manipulated variables of
Third, it determines whether the θ-S converter 54 that outputs the set position of the forward / reverse switching lever 49 as a digital signal functions normally, and is provided in various elements of the central processing unit 60. The operation of the data table, the counter, and the flag area are checked, and the detection signals from the sensor group 90 are input to determine whether or not these detection signals are normal.

Step 4 The central processing unit 60 registers activation in the system table after judging that the operation of each part constituting the control system can function normally.

Step 5 When the processing from Step 1 to Step 4 is completed,
Since the preparation for running the electric vehicle is completed, the central processing unit 60 next sets the setting positions of the operation mode switching lever 46 and the forward / reverse switching lever 49 set by the driver to the θ-S converter 51 and the θ-S converter 51. It is input as a contact signal output from the S converter 54. The contact signal output from the θ-S converter 51 is, for example, 100000 when the operation mode is in the neutral mode, and 010000 when the operation mode is in the parking mode.
A digital signal such as 11111111 when set to forward, 111111100 when set to reverse.

Step 6 The central processing unit 60 determines the currently set operation mode based on the contact signal relating to the operation mode input in step 5, and determines whether the vehicle is moving forward or backward based on the signal relating to forward / reverse travel. Determine if there is.

Step 7 The central processing unit 60 determines the rotation angle of the steering wheel 45, the depression amount of the accelerator pedal 47 and the brake pedal 48, that is, the operation amount,
In addition, a detection signal from the sensor group 90 and the like is input, and these input data are stored in the traveling management data collection unit 62.

Step 8 This step will be described in detail later. In this step, the following process is performed. That is, the control device 100 processes the various data input in step 7 according to the driving mode set by the driving mode switching lever 46 and the traveling direction set by the forward / reverse switching lever 49, and , 20,..., The output torque and the steering angle are calculated, and the electric vehicle is caused to travel as the driver intends.

Step 9 If the key is operated and the power is turned off, the central processing unit 60 terminates the process, and if the key is turned on, the central processing unit 60 repeats steps 5 to 9 to perform the process. That is, while the key is turned on, the processing from step 5 to step 9 is repeatedly performed.

Next, FIG. 8 shows a flowchart of a subroutine program of step 3 in the main flowchart shown in FIG.

This subroutine program is a start-up check program, and there are various types of checks that are actually performed. In this flowchart, a sensor group, which is a typical start-up check of the checks, is shown.
The flowchart regarding the inspection processing of 90 is shown. Note that the other inspections are performed by the same processing as the flowchart shown in the same figure, and thus the detailed description of these operations will be omitted.

Step 10 First, the central processing unit 60 inputs the detection signals of all the sensors of the sensor group 90 composed of, for example, a motor current detection sensor, a motor temperature detection sensor, a battery voltage detection sensor, etc.
Then, these detection signals are stored.

Step 11: The traveling allowance determining unit 61 individually extracts the signals from the sensors stored in the traveling management data collecting unit 62 in Step 10, and sequentially determines whether or not the signals are normal. A determination is made as to whether the sensor is functioning properly. For example, if the sensor is damaged, no detection signal is output or a detection value that is far from the actual value is output, and this is compared with the reference value assigned to each sensor. By doing so, the abnormality of the sensor is detected. The abnormality determination of the sensor can be performed by another method that is generally used in addition to the above method.

Step 12 As a result of the abnormality determination processing in step 11, if no abnormality is found in any of the sensors, the subroutine is terminated and the process returns to the main routine. If any abnormality is found in one of the sensors, Proceed to the next step.

Step 13 When the traveling allowance judging section 61 detects a sensor having an abnormality, the occurrence of abnormality of the sensor is indicated on the display device.
Display by 95. Then, after this display, the subroutine ends and returns to the main routine.

Next, FIG. 9 shows a subroutine program of step 6 in the main flowchart shown in FIG. In this subroutine program, only the subroutine program for detecting the operation mode set by the operation mode switching lever 46 is shown. The description is omitted because it is the same as the program. Further, the electric vehicle exemplified in the present embodiment is provided with the various operation modes as described above, so that the traveling direction can be selected.
Specifically, the operation modes include a neutral mode, a parking mode, a normal mode, a skew mode, and a rotation mode, and the traveling direction can be selected from forward, backward, right rotation, and left rotation. I have. Therefore, as the traveling state of the electric vehicle, each traveling state of forward and backward in the normal mode, forward and backward in the skew mode, right rotation and left rotation can be realized. Further, although a specific flowchart is not shown here, when the stop time is equal to or longer than a predetermined time, the operation mode can be automatically set to the neutral or parking mode.

Step 20 The central processing unit 60 inputs a contact signal output as a digital value from the θ-S converter 51 by operating the operation mode switching lever 46.

Step 21 The central processing unit 60 detects the set position of the operation mode switching lever 46 based on the input contact signal.

Step 22 Upon detecting the set position, the central processing unit 60 calculates the operation mode from the set position.

Step 23 The central processing unit 60 outputs the operation mode calculated in step 22 to the switching units 55 and 56 shown in FIGS. 5 and 6 described above, and in accordance with the operation mode, the switching unit 55 And 56 contacts are switched. Then, the subroutine ends and the process returns to the main routine. Needless to say, the traveling direction selected by the forward / reverse switching lever 49 is also input to the central processing unit 60, and the rotation direction of each of the electric wheels 20, 20,... Is determined based on this traveling direction.

Further, FIG. 10 and subsequent figures show a subroutine program of step 8 in the main flowchart shown in FIG.

This subroutine program is a subroutine program for displaying on the display device 95 in each operation mode or calculating output torque and steering angle of each electric wheel 20. The subroutine program shown in FIG. 10 is a subroutine program when the selected operation mode is neutral.

Step 30 The central processing unit 60, upon judging the operation mode set by the operation mode switching lever 46 by the subroutine program shown in FIG. 9, displays the judged operation mode on the display device 95. That is, in this case, neutral is displayed.

Step 31 The central processing unit 60 displays, for example, the vehicle speed of the electric vehicle (in this case, the vehicle speed is 0 if no special driving is performed), the display of various other data at the request of the driver, and the like. It is displayed on the device 95.

That is, in this operation mode, the display device 95 displays the vehicle speed and the like.
Only the display indicating the running state of the electric vehicle and the data requested by the driver are displayed.Even if the accelerator pedal 47 and the brake pedal 48 are operated, the operation of the electric wheel 20 is not affected. Has become.

Next, the subroutine program shown in FIG. 11 is a subroutine program when the selected operation mode is parking.

Step 40 The central processing unit 60 determines that the operation mode set by the operation mode switching lever 46 is the parking mode by the subroutine program shown in FIG. Activate the brakes and stop the electric vehicle.

Step 41 Next, the central processing unit 60 displays the determined operation mode on the display device 95. That is, in this case, parking is displayed.

Step 42 Then, the central processing unit 60 displays, for example, the vehicle speed of the electric vehicle, the display of various other data according to the driver's request, and the like on the display device 95 in the same manner as described above.

That is, in this driving mode, only the display indicating the running state of the electric vehicle such as the vehicle speed and the data required by the driver are displayed on the display device 95 as in the case of the neutral mode. 48
Is operated so as not to affect the operation of the electric wheel 20.

The subroutine programs shown in FIGS. 12A and 12B are subroutine programs when the selected operation mode is the skew mode. This skew mode is a mode in which all the electric wheels 20, 20,... Are steered in the same direction at the same steering angle by operating the steering wheel 46, and is a mode in which the electric vehicle is moved forward or backward diagonally. is there.

Hereinafter, the operation of the control device for an electric vehicle of the present invention when the skew mode is selected will be described in detail.

Step 50 If the central processing unit 60 determines that the set position of the operation mode switching lever 46 is in the skew mode, the mode data stored in the storage device provided in the central processing unit 60 is skewed. Rewrite to line mode data.
When this mode is selected, a switching signal is output from the θ-S converter 51 to the switching units 55 and 56 as shown in FIGS. 5 and 6, and based on this switching signal, the switching units 55 and 56 θ−
The contacts are switched so that the signal from the V converter 50 is input to the skew steering angle calculation unit 81 and the signal from the skew steering angle calculation unit 81 can be output to the steering angle command unit 82. .

Step 51 The skew steering angle calculation section 81 inputs a voltage output from the θ-V converter 50 and proportional to the rotation angle of the handle 45.

Step 52 The skew steering angle calculation unit 81 calculates the steering angle of each electric wheel 20 based on the voltage input in the previous step and proportional to the rotation angle of the steering wheel 45. That is, when the voltage output from the theta-V converter 50 by the rotation of the handle 45 is assumed to be V _1, skew steering angle calculating section 81, a steering angle based on the voltage V _1, the storage device (not shown) The calculation is performed by looking up stored data.

Step 53: The rotation direction determination unit 71 determines the rotation direction of each of the electric wheels 20, 20,... Based on the signal output from the forward / reverse switching lever 49, and supplies the electric power to each of the electric wheels 20, 20,. Are given to the gate controller 74 for controlling the rotation of the electric wheels 20, 20,... In the determined rotation direction. The rotation direction of each of the electric wheels 20, 20,... Is determined by the direction of the skew mode selected by the forward / reverse switching lever 49. That is, the rotation direction is determined depending on whether the mode is the forward skew mode or the backward skew mode.

Step 54 The PID nonlinear controller 67 receives the voltage output from the θ-V converter 52 by operating the accelerator pedal 47.

Step 55 As in the previous step, the PID nonlinear control section 67 inputs the voltage output from the θ-V converter 53 by operating the brake pedal 48.

Step 56: The PID nonlinear control unit 67 determines whether the θ-V converter is in accordance with the amount of depression of the accelerator pedal 47 and the amount of depression of the brake pedal 48.
A difference between the two voltages output from 52 and 53 is calculated, and a command value of a torque to be given to each of the electric wheels 20, 20,... Is calculated based on the voltage value obtained as a result of the calculation. It should be noted that even during the calculation of this command value, strictly speaking, the depression amount of the accelerator pedal 47 and the depression amount of the brake pedal 48 are not necessarily kept constant.
Is provided with a dead zone in the same meaning as in the conventional play so that even if the amount of depression varies within a certain range, the calculation is not affected.
The slight change in the amount of depression can be ignored. The actual determination of the dead zone is made by determining whether or not the input, that is, the absolute value of the voltage value is equal to or greater than a predetermined value. It is determined that the accelerator pedal 47 and the brake pedal 48 have been operated.

Step 57 Next, the PID nonlinear control section 67 calculates the load torque currently generated by each of the electric wheels 20, 20,... Based on the voltage value output from the signal processing section 87. That is, as shown in FIG. 5, the signal processing unit 87 receives the effective value of the voltage applied to the motor from the power control unit 75, which supplies power to the motor of the electric wheel 20, and supplies the power to the motor. And the effective value of the current from the F / V converter 86 which outputs a voltage proportional to the pulse frequency output from the magnetic pole position detecting element 85 in accordance with the rotation of the motor. Is input, the signal processing unit 87 performs a collective operation on these voltage values or current values, and outputs a signal relating to the load torque of the motor 2 to the PID nonlinear control unit 67 as a voltage value. Therefore, the PID nonlinear controller 67
By inputting this voltage value and calculating the voltage value, the current load torque carried by the motor can be calculated in real time.

Step 58 The PID nonlinear control section 67 performs a nonlinear correction calculation of the load torque of the motor calculated in the previous step. That is, this non-linear correction is a known correction that is also used in conventional electric vehicles and the like, and particularly in the case of electric vehicles, it is performed to improve operability and feeling during starting and acceleration. .

Step 59 The PID nonlinear control section 67 calculates a torque deviation, that is, a torque that must be further applied to the motor 2, from the torque command value calculated in Step 56 and the motor load torque calculated in Step 57. Also in this case, when the torque deviation is small, the torque deviation can be ignored, that is, a dead zone is provided in the same meaning as the play of the accelerator pedal 47 and the brake pedal 48 described above. I have. The actual determination of the dead zone is made by comparing a reference torque deviation prepared in advance with the torque deviation. When the torque deviation is equal to or more than a predetermined value, it is determined that a torque deviation has occurred.

Step 60 The PID non-linear controller 67 calculates a voltage value to be applied to the motor to reduce the torque deviation to 0 based on the torque deviation calculated in the previous step, and sends the calculation result to the supply voltage controller 72. Output. In this case, the voltage output to the supply voltage control unit 72 is the voltage after the integration process has been performed, and the operation mode in this case is the skew mode selected when the vehicle is parked and stopped. Control unit 6
7 is also provided with a speed limiter function so that an excessive speed is not produced due to an operation error of the accelerator pedal 47. In other words, in this skew mode, for example, 20KM
/ H or higher speed cannot be issued.

Step 61 The PID nonlinear control section 67 calculates the torque ratio for each of the electric wheels 20, 20,. In this case, since the operation mode is the skew mode, the torque ratio of each of the electric wheels 20, 20,.
It rotates with the same torque according to the amount of depression of 47.

Step 62 The supply voltage control section 72 is provided in the battery group 76 to be selected by the tap switching section 77 in accordance with the voltage value for setting the torque deviation output from the PID nonlinear control section 67 to 0, not shown. Calculate the tap switching position. The battery group 76 includes, for example, ten 12 V batteries connected in series, and a tap is provided at a connection point of each battery. By switching this tap by tap switching unit 77, a maximum of 120V
The voltage can be applied to the power control unit 75 in steps of 12V from the minimum to 12V.

Step 63 In addition, the supply voltage control unit 72 calculates an optimum pulse width in the voltage supplied through the tap selected in the previous step in order to drive each of the electric wheels 20, 20,.

Step 64: The rotation direction judging section 71 gives the gate control section 74 a step 53
Are given so that each of the electric wheels 20, 20,... Rotates in the rotation direction determined in step.

Step 65 The skew steering angle calculation unit 81 outputs the signal regarding the steering angle of each electric wheel 20 calculated in step 52 to the steering angle command unit 82 as a steering angle command value.

Step 66 The steering angle command section 82 activates the steering angle servo 83 based on the steering angle command value output in the previous step, activates the steering actuator 40, and controls the electric wheels 20, 20,. The same steering angle is set in proportion to the rotation angle. As a result, the electric vehicle can run diagonally.

Step 67 The supply voltage control section 72 outputs a signal to switch taps to the tap switching section 77 based on the optimum tap position calculated in step 62.

Step 68 The tap switching section 77 operates the pulse motor for switching the tap, and switches the tap provided in the battery group 76 to the optimum tap position. When this tap is switched, the voltage switched by this tap is always applied from the battery group 76 to the power control unit 75. At the time of this tap change, the voltage applied to the power control unit 75 changes abruptly, and therefore, a process for preventing the occurrence of spark generated at the time of tap change is also performed.

Step 69 The supply voltage controller 72 outputs this pulse width ratio to the pulse train generator 73 based on the pulse width ratio calculated in step 63.

Step 70 The pulse train generator 73 determines an on-level section within one pulse of the fundamental frequency determined by the clock signal based on the pulse width ratio output from the supply voltage controller 72 in the previous step. The pulse width modulated basic clock is output to the gate control unit 74. Then, the gate control unit 74 controls the pulse width-modulated basic clock, the signal related to the rotation direction output from the rotation direction determination unit 71, and the motor 2 output from the magnetic pole position detection element 85.
The rectification timing direction for each magnetic pole polarity of the motor 2 is determined while taking into account the pulse generated due to the rotation of the motor 2.
This timing-controlled pulse width modulation signal (hereinafter referred to as PWM
It is called a signal. ) Is output to the power control unit 75. Next, the power control unit 75 chops the voltage applied by the battery group 76 based on the PWM signal output from the gate control unit 74, and applies the voltage after pulse width modulation to the coil of the motor. The power control unit 75 uses a large number of power transistors, and the effective value of the voltage applied to the motor is controlled by controlling the ON time of the power transistor.

Step 71 Each of the electric wheels 20, 20,... Is driven by the voltage output from the power control unit 75. Since this operation mode is a skew mode, the same voltage is applied to all the electric wheels 20, and each of the electric wheels 20, 20,.
And the same direction of rotation according to the amount of depression.

Step 72 The central processing unit 60, upon judging the operation mode set by the operation mode switching lever 46 by the subroutine program shown in FIG. 9, displays the judged operation mode on the display device 95. That is, in this case, the skew mode is displayed.

Step 73 Then, the central processing unit 60 displays on the display device 95, for example, a display necessary for driving, such as the vehicle speed of the electric vehicle, or a display of various other data at the request of the driver, and returns to the main routine.

As described above, when the driving mode is the skew mode, the steering angles of the electric wheels 20, 20,... Are all steered in the same direction according to the rotation angle of the steering wheel 45, and at the same time, the accelerator pedal 47 is By operating the forward / backward switching lever
Based on the driving direction selected by 49, the electric vehicle can be driven to run forward or backward. Therefore, it is possible to easily park even in a place where the parking space is narrow, and when a trouble such as derailing occurs, it is easy to escape from the trouble by effectively using this mode. It becomes possible.

Next, the subroutine program shown in FIGS. 13A and 13B will be described. This subroutine program is a subroutine program when the selected operation mode is the rotation mode. The rotation mode is a mode in which the electric vehicle is rotated on the spot regardless of the operation of the steering wheel 46. That is, when this rotation mode is selected, the steering angle of each of the electric wheels 20, 20,... Is set to such an angle that the electric vehicle can rotate on the spot about the center of gravity of the four electric wheels 20. .

This driving mode is a very convenient mode to be used when making a U-turn in a very narrow place. Naturally, when making a turn, the area where a circle with a diameter equal to the length of the electric vehicle can be drawn is minimum. If limited, electric vehicles will be able to turn in place.

Hereinafter, the operation of the control device for an electric vehicle according to the present invention in this rotation mode will be described.

Steps 80 and 81 When the central processing unit 60 determines that the set position of the operation mode switching lever 46 is the rotation mode, the mode data stored in the storage device provided in the central processing unit 60 is changed to the rotation mode. Rewrite with data. When this mode is selected, as shown in FIG. 5 and FIG.
A switching signal is output from the S converter 51 to the switching units 55 and 56,
On the basis of this switching signal, the switching units 55 and 56
The contacts are switched so that a signal from the rotary steering angle table 68 is input to the rotary steering angle table 68 and a signal from the rotary steering angle table 68 can be output to the steering angle command unit 82.

Step 82: The rotation direction determination unit 71 determines the rotation direction of each of the electric wheels 20, 20,... Based on the signal output from the θ-S converter 54,
Gate control unit that controls the power supplied to each motorized wheel 20, 20, ...
An instruction for rotating each of the electric wheels 20, 20,... In the determined rotation direction is given to 74. The rotation direction of each of the electric wheels 20, 20,... Is determined by the direction of rotation selected by the forward / reverse switching lever 49. That is, the rotation direction is determined depending on whether the rotation mode is the right rotation mode or the left rotation mode. For example, when the right rotation mode is set, the electric wheels 20 arranged in the front light and the rear right rotate in the backward direction, and the electric wheels 20 arranged in the front left and the rear left move in the forward direction. Will rotate.
The rotation speeds of these electric wheels 20 are, of course, all the same.

Step 83: The PID nonlinear control section 67 receives the voltage output from the θ-V converter 52 by operating the accelerator pedal 47.

Step 84 As in the previous step, the PID nonlinear control section 67 inputs the voltage output from the θ-V converter 53 by operating the brake pedal 48.

Step 85 The PID non-linear controller 67 determines whether the θ-V converter is in accordance with the depression amount of the accelerator pedal 47 and the depression amount of the brake pedal 48.
The difference between the two voltages output from 52 and 53 is calculated, and the command value of the torque to be given to each of the electric wheels 20, 20,... Is calculated based on the voltage value obtained as a result of this calculation. Strictly speaking, even while the command value is being calculated, the depression amount of the accelerator pedal 47 and the depression amount of the brake pedal 48 are not necessarily kept constant. A dead zone is provided in the same sense as in the conventional play, so that even if the stepping amount of the pedal fluctuates within a certain range, the calculation is not affected, that is, a slight change in the stepping amount of both pedals 47 and 48 is provided. Can be ignored. The determination of the dead zone in practice is made by determining whether or not the input, that is, the absolute value of the voltage value is equal to or greater than a predetermined value. It is determined that the pedal 47 and the brake pedal 48 have been operated.

Step 86 Next, the PID nonlinear control section 67 calculates the load torque that is currently occurring in each of the electric wheels 20, 20,... Based on the voltage value output from the signal processing section 87. That is, as shown in FIG. 5, an effective value of the voltage applied to the motor 2 from the power control unit 75 for supplying power to the motor 2 of the motor-driven wheel 20 is supplied to the signal processing unit 87. And the effective value of the current from the F / V converter 86 which outputs a voltage proportional to the pulse frequency output from the magnetic pole position detection element 85 in accordance with the rotation of the motor 2. The value is input, and the signal processing unit 87 performs a collective operation on these voltage values or current values, and uses the signal relating to the load torque of the motor 2 as a voltage value as a PID nonlinear control unit 6.
7 is output. Therefore, the PID nonlinear control section 67 receives the voltage value and calculates the voltage value, whereby the current load torque carried by the motor 2 can be calculated in real time.

Step 87 The PID nonlinear control section 67 performs a nonlinear correction calculation of the load torque on the motor 2 calculated in the previous step. That is, this non-linear correction is a known correction that is also used in conventional electric vehicles and the like, and particularly in the case of electric vehicles, it is performed to improve operability and feeling during starting and acceleration. . In the case of this operation mode, it is necessary to rotate the electric vehicle with a very slow operation for safety reasons. Therefore, this non-linear correction calculation is performed to improve operability.

Step 88 The PID nonlinear control section 67 calculates a torque deviation from the torque command value calculated in Step 85 and the motor load torque calculated in Step 86, that is, a torque that must be further applied to the motor 2. In this case, when the torque deviation is very small, the torque deviation can be ignored, that is, a dead zone is provided in the same meaning as the play of the accelerator pedal 47 and the brake pedal 48 described above. . The actual determination of the dead zone is made by comparing a reference torque deviation prepared in advance with the torque deviation. When the torque deviation is equal to or more than a predetermined value, it is determined that a torque deviation has occurred.

Step 89: Based on the torque deviation calculated in the previous step, the PID nonlinear control section 67 calculates a voltage value to be applied to the motor 2 in order to reduce the torque deviation to 0, and outputs the calculation result to the supply voltage control section 72. Output to In this case, the voltage output to the supply voltage control unit 72 is the voltage after the integration process is performed, and the operation mode in this case is a rotation mode selected at the time of a U-turn of the electric vehicle, etc. The PID non-linear control section 67 also has a speed limiter function so that an unnecessary speed is not generated due to an operation error of the accelerator pedal 47. That is, in this rotation mode, for example, a speed of 4 KM / H or more cannot be obtained.

Step 90 The PID nonlinear control section 67 calculates a torque ratio for each of the electric wheels 20, 20,. In this case, since the operation mode is the rotation mode, the torque ratio of each of the electric wheels 20, 20,... Is 1 as described above, and the respective electric wheels 20 are the same in accordance with the depression amount of the accelerator pedal 47. It will rotate at speed.

Step 91 The supply voltage control section 72 is provided in the battery group 76 to be selected by the tap switching section 77 in accordance with the voltage value for setting the torque deviation output from the PID nonlinear control section 67 to 0, not shown. Calculate the tap switching position. As described above, the battery group 76 includes, for example, ten 12 V batteries connected in series, and a tap is provided at a connection point of each battery. The tap is switched by the tap switching unit 77, and the power control unit is switched from a maximum of 120V to a minimum of 12V in 12V steps.
A voltage can be applied to 75. In the case of this rotation mode, since it is not necessary to increase the rotation speed of the electric wheels 20, each electric wheel 20, 20,... Is actually rotated by a voltage of about 12V or 24V. .

Step 92 Further, the supply voltage control section 72 calculates an optimum pulse width in the voltage supplied through the tap selected in the previous step, in order to drive each of the electric wheels 20, 20,.

Step 93 The rotation direction judging section 71 gives a command relating to the rotation direction to the gate control section 74 so that the electric wheels 20, 20,... Rotate in the rotation direction judged in Step 82.

Step 94 The steering angle command section 82 extracts data on the steering angle of each electric wheel 20 stored in the rotary steering angle table 68.

Step 95 The steering angle command unit 82 activates the steering angle servo 83 based on the data on the steering angle extracted in the previous step, activates the steering actuator 40, and electrically operates the center of gravity of the four electric wheels 20. Each of the electric wheels 20, 20,... Is set at an angle at which the car can rotate on the spot. Therefore, the electric vehicle can make a U-turn in a very narrow place.

Step 96 The supply voltage control section 72 outputs a signal to switch taps to the tap switching section 77 based on the optimum tap position calculated in step 91.

Step 97 The tap switching section 77 operates the pulse motor for switching the tap, and switches the tap provided in the battery group 76 to the optimum tap position. When the tap is switched, the voltage switched by the tap is always applied from the battery group 76 to the power control unit 75. At the time of this tap change, the voltage applied to the power control unit 75 changes abruptly, and therefore, a process for preventing the occurrence of spark generated at the time of tap change is also performed.

Step 98 The supply voltage controller 72 outputs the pulse width ratio to the pulse train generator 73 based on the pulse width ratio calculated in step 92.

Step 99: The pulse train generator 73 determines an on-level section within one pulse of the fundamental frequency determined by the clock signal based on the pulse width ratio output from the supply voltage controller 72 in the previous step. The pulse width modulated basic clock is output to the gate control unit 74. The gate control unit 74 generates the pulse width modulated basic clock, the signal related to the rotation direction output from the rotation direction determination unit 71, and the rotation of the motor output from the magnetic pole position detection element 85. The rectification timing direction for each magnetic pole polarity of the motor is determined in consideration of the pulse to be performed, and this timing-controlled PWM signal is output to the power control unit 75. Next, the power control unit 75 chops the voltage applied by the battery group 76 based on the PWM signal output from the gate control unit 74, and applies the voltage after pulse width modulation to the coil of the motor.

Step 100 Each of the electric wheels 20, 20,... Is driven by the voltage output from the power control unit 75. In the case of this operation mode, since it is the rotation mode, the same voltage is applied to all the electric wheels 20, and each of the electric wheels 20, 20,... Corresponds to the depression amount of the accelerator pedal 47. It rotates in the above-mentioned predetermined direction at the same speed.

Step 101 When the operation mode set by the operation mode switching lever 46 is determined by the subroutine program shown in FIG. 9, the central processing unit 60 displays the determined operation mode on the display device 95. That is, in this case, the rotation mode is displayed.

Step 102 Then, the central processing unit 60 displays, on the display device 95, a display necessary for driving, such as the speed of the electric vehicle, or a display of various other data at the request of the driver, and returns to the main routine.

As described above, when the operation mode is the rotation mode, the steering angles of the electric wheels 20, 20,... Are stored in the rotation steering angle table 68 in advance regardless of the rotation angle of the steering wheel 45. Based on only the steering angle data for each motorized wheel, the angle is set such that the electric vehicle can rotate on the spot about the center of gravity of the four motorized wheels 20 arranged. Therefore, electric vehicles can be used in extremely
It is possible to make a turn, and by selecting this operation mode, it is possible to perform a highly mobile operation.

Next, the subroutine program shown in FIGS. 14A and 14B is a subroutine program in a case where the selected mode is a normal mode which is usually used most often. The normal mode is a mode in which the electric vehicle is driven according to the driver's intention based on signals from the steering wheel 45, the accelerator pedal 47, the brake pedal 48, and the forward / reverse switching lever 49. In this case, each electric wheel 20,20,…
The steering angle of the motorized wheel 2 is adjusted by the steering wheel 45.
The torques output from 0, 20,... Are adjusted by operating amounts of the steering wheel 45, the accelerator pedal 47, and the brake pedal 48 mutually.

Hereinafter, the operation of the control device for an electric vehicle of the present invention when this normal mode is selected will be described in detail.

Step 110 When the central processing unit 60 determines that the set position of the operation mode switching lever 46 is the normal mode, the mode data stored in the storage device provided in the central processing unit 60 is selected. Rewrite the data in the normal mode. When this mode is selected, as shown in FIGS. 5 and 6, the θ-S converter 51
A switching signal is output to 56, and based on the switching signal, the switching units 55 and 56 allow the signals from the θ-V converter 50 to be input to the four-wheel steering angle calculation unit 66 and the four-wheel torque ratio calculation unit 64. To
A signal from the four-wheel steering angle calculation unit 66 is transmitted to the steering angle command unit 82.
The contact is switched so that the signal can be output to the contact. Further, a signal related to the traveling direction selected by the forward / reverse switching lever 49 is output to the rotation direction determination unit 71 via the θ-S converter 54, and the rotation direction determination unit 71 The rotation direction of the wheels 20, 20,... Is determined.

Step 111: Based on the traveling direction selected by the forward / reverse switching lever 49, the rotation direction determining unit 71 causes the gate control unit 74 to move each electric wheel 20, 20, 20 to move the electric vehicle in the selected traveling direction. .. Are given.

Step 112 The four-wheel steering angle calculation unit 66 and the four-wheel torque ratio calculation unit 64 calculate θ
The operation amount of the handle 45 output from the -V converter 50, that is, a voltage proportional to the rotation angle is input.

Step 113: The PID nonlinear control section 67 outputs a pulse signal output from the magnetic pole position detecting element 85 attached to the motor 2 constituting each of the electric wheels 20, 20,... For each unit rotation angle of the motor 2. Is input via the F / V converter 86 and the signal processing unit 87, and the speed of the electric vehicle is sensed based on the pulse signal.

Step 114 The four-wheel steering angle calculation unit 66 calculates the steering angle of each electric wheel 20 based on the voltage input in the previous step and proportional to the rotation angle of the steering wheel 45. That is, when the voltage output from the theta-V converter 50 by the rotation of the handle 45 is assumed to be V _1, the four-wheel steering angle calculation section 66 look-up from a storage device (not shown) the steering angle based on the voltages V ₁ To calculate.

Step 115 In addition, the four-wheel torque ratio calculating unit 64 calculates each of the electric wheels 2 based on the steering angle of each of the electric wheels 20, 20,.
.., The torque ratio of each wheel to each reference torque (torque calculated by the amount of depression of the accelerator pedal 47) is calculated. By performing this correction, the electric wheels 20 set to different steering angles by operating the steering wheel 45 are rotated with different torques, thereby enabling a smooth turning of the electric vehicle.

Step 116 The PID nonlinear control section 67 receives the voltage output from the θ-V converter 52 by operating the accelerator pedal 47.

Step 117 As in the previous step, the PID nonlinear control section 67 receives the voltage output from the θ-V converter 53 by operating the brake pedal 48.

Step 118: The PID nonlinear control unit 67 determines whether the θ-V converter 52 is in accordance with the amount of depression of the accelerator pedal 47 and the amount of depression of the brake pedal 48.
, And 53, and calculates a command value of a torque to be given to each of the electric wheels 20, 20,... Based on the voltage value obtained as a result of the calculation. Strictly speaking, even while the command value is being calculated, the depression amount of the accelerator pedal 47 and the depression amount of the brake pedal 48 are not necessarily kept constant. A dead zone is provided in the same sense as in the conventional play, so that even if the stepping amount of the pedal fluctuates within a certain range, the calculation is not affected, that is, a slight change in the stepping amount of both pedals 47 and 48 is provided. Can be ignored. The determination of the dead zone in practice is made by determining whether or not the input, that is, the absolute value of the voltage value is equal to or greater than a predetermined value. It is determined that the pedal 47 and the brake pedal 48 have been operated.

Step 119 Next, the PID nonlinear control section 67 calculates the load torque currently generated for each of the electric wheels 20, 20,... Based on the voltage value output from the signal processing section 87. That is, as shown in FIG. 5, an effective value of the voltage applied to the motor 2 from the power control unit 75 for supplying power to the motor 2 of the motor-driven wheel 20 is supplied to the signal processing unit 87. And the effective value of the current from the F / V converter 86 which outputs a voltage proportional to the pulse frequency output from the magnetic pole position detection element 85 in accordance with the rotation of the motor 2. The value is input, and the signal processing unit 87 performs a collective operation on these voltage values or current values, and uses the signal relating to the load torque of the motor 2 as a voltage value as a PID nonlinear control unit 6.
7 is output. Therefore, the PID nonlinear control section 67 inputs this voltage value, and by calculating this voltage value, can calculate the current load torque carried by the motor 2 in real time.

Step 120 The PID nonlinear control section 67 performs a nonlinear correction calculation of the load torque on the motor 2 calculated in the previous step. Although the details of this correction calculation will be described later, generally, this nonlinear correction is a known correction that is also used in a conventional electric vehicle or the like. This is done to improve the operability and feeling in

Step 121 The PID nonlinear control section 67 calculates a torque deviation from the torque command value calculated in step 118 and the motor load torque calculated in step 119, that is, a torque that must be further applied to the motor 2. In this case, when the torque deviation is very small, the torque deviation can be ignored, that is, a dead zone is provided in the same meaning as the play of the accelerator pedal 47 and the brake pedal 48 described above. . The actual determination of the dead zone is performed by comparing a reference torque deviation prepared in advance with the torque deviation. When the torque deviation is equal to or larger than a predetermined value, it is determined that a torque deviation has occurred.

Step 122 The PID nonlinear control section 67 calculates a voltage value to be applied to the motor 2 in order to reduce the torque deviation to 0 based on the torque deviation calculated in the previous step, and outputs the calculation result to the supply voltage control section 72. Output to In this case, the voltage output to the supply voltage control unit 72 is the voltage after the integration process has been performed, and the output voltage is also limited so that the electric wheel 20 is not overloaded.

Step 123 The PID nonlinear control section 67 calculates a torque ratio for each electric wheel 20, 20,.... In this case, since the operation mode is the normal mode, the torque ratio of each of the electric wheels 20, 20,... Changes according to the operation amount of the steering wheel 45.

Step 124: The supply voltage control unit 72 is provided in the battery group 76 to be selected by the tap switching unit 77 according to the voltage value for setting the torque deviation output from the PID nonlinear control unit 67 to 0, not shown. Calculate the tap switching position. For example, if a very large torque is required to reduce the torque deviation to zero, a tap position for applying a voltage of 120 V is calculated. In the calculation of the tap position, a dead zone is provided so that the optimum tap position does not frequently change based on a frequent change in the amount of depression of the accelerator pedal 47 or the brake pedal 48. Switching is minimized.

Step 125 Further, the supply voltage control unit 72 uses the tap selected in the previous step to drive each of the electric wheels 20, 20,.
The optimum pulse width at the voltage supplied to the motor 2 is calculated.

Step 126 The four-wheel steering angle calculation unit 66 outputs the signal regarding the steering angle of each electric wheel 20 calculated in step 114 to the steering angle command unit 82 as a steering angle command value.

Step 127 The steering angle command section 82 operates the steering angle servo 83 based on the steering angle command value output in the previous step, operates the steering actuator 40, and controls the electric wheels 20, 20,. Set the steering angle in proportion to the rotation angle. As a result, the electric vehicle can be turned. In this case, the steering angle of the electric wheels 20 is, for example, such that the electric wheels 20, 20 constituting the rear wheels change the steering angle by 1/5 of the electric wheels 20, 20 constituting the front wheels, or In this case, the steering angle with respect to the front wheels may be in the same phase direction at a certain vehicle speed or higher, or in the opposite phase direction at a certain vehicle speed or lower.
Further, the steering angle may be changed continuously according to the vehicle speed.

Step 128 The supply voltage control section 72 outputs a signal to switch taps to the tap switching section 77 based on the optimum tap position calculated in step 124.

Step 129: The tap switching section 77 operates the pulse motor for switching the tap, and switches the tap provided in the battery group 76 to the optimum tap position. When this tap is switched, the voltage switched by this tap is always applied from the battery group 76 to the power control unit 75. At the time of this tap change, the voltage applied to the power control unit 75 changes abruptly, and therefore, a process for preventing the occurrence of spark generated at the time of tap change is also performed.

Step 130 The supply voltage controller 72 outputs this pulse width ratio to the pulse train generator 73 based on the pulse width ratio calculated in step 125.

Step 131 The pulse train generating unit 73 determines an ON level within one pulse of the fundamental frequency determined by the clock signal based on the pulse width ratio output from the supply voltage control unit 72 in the previous step. The pulse width modulated basic clock is output to the gate control unit 74. The gate control unit 74 generates the pulse width modulated basic clock, the signal related to the rotation direction output from the rotation direction determination unit 71, and the rotation of the motor output from the magnetic pole position detection element 85. The rectification timing direction for each magnetic pole polarity of the motor is determined in consideration of the pulse to be performed, and this timing-controlled PWM signal is output to the power control unit 75. Next, the power control unit 75 chops the voltage applied by the battery group 76 based on the PWM signal output from the gate control unit 74 and applies the voltage after pulse width modulation to the coil of the motor.

Step 132 Each of the electric wheels 20, 20,... Is driven by the voltage output from the power control unit 75. In this operation mode,
In the normal mode, each electric wheel 20, 20,... Has a steering wheel 45 unless the electric vehicle is traveling completely straight.
, Different voltages are applied in accordance with the amount of operation, and the respective electric wheels 20, 20,... Rotate with different optimum torques.

Step 133 When the operation mode set by the operation mode switching lever 46 is determined by the subroutine program shown in FIG. 9, the central processing unit 60 displays the determined operation mode on the display device 95. That is, in this case, the normal mode is displayed.

Step 134 Then, the central processing unit 60 displays on the display device 95, for example, a display necessary for driving, such as the speed of the electric vehicle, or a display of various other data at the request of the driver, and returns to the main routine.

As described above, in the normal mode in the above-described flowchart, the steering angle of each of the electric wheels 20, 20,... Changes according to the rotation angle of the steering wheel 45. ,... Are calculated based on the rotation angle of the steering wheel 45 and the amounts of depression of the accelerator pedal 47 and the brake pedal 48.

FIGS. 15A and 15B show a flowchart for accelerating the electric vehicle, that is, a detailed flowchart of the acceleration process. This acceleration process is a process that is frequently performed during the running of the electric vehicle, and is an important process that has a significant effect on the driving feeling. Hereinafter, this processing will be described.

Step 140 The PID nonlinear control section 67 receives the voltage output from the θ-V converter 52 by operating the accelerator pedal 47. In other words, the acceleration torque (+ value) based on the operation amount of the accelerator pedal 47 is calculated.

Step 141 Next, the PID nonlinear control section 67 inputs a voltage output from the θ-V converter 53 by operating the brake pedal 48. In other words, the deceleration torque (-value) based on the operation amount of the brake pedal 48 is calculated.

Step 142 The PID nonlinear controller 67 calculates the difference between the voltage output from the θ-V converter 52 and the voltage output from the θ-V converter 53. If this difference is a positive value, the driver is requesting acceleration of the electric vehicle.

Step 143 The PID nonlinear control section 67 calculates the requested acceleration torque, that is, the target torque obtained by adding the deviation acceleration torque to the current load torque, based on the voltage difference calculated in the previous step. This calculation is performed by looking up a data table in which the relationship between the voltage and the torque is stored in advance. That is, when the voltage is V1, the target torque is T1, when the voltage is V2, T2 ...
The torque corresponding to the voltage closest to the voltage is selected as the target torque from the data of..., And the target torque is calculated.

Step 144 The PID nonlinear control section 67 checks whether or not the target torque determined in the previous step is within a preset dead band so as not to change sensitively to a slight operation of the accelerator or the brake pedal. That is, a play is provided between the accelerator pedal 47 and the brake pedal 48. This check, for example, step
It is performed by comparing whether the voltage difference calculated in 142 is larger or smaller than the voltage previously set as the dead band, and when the voltage difference is smaller than the voltage previously set as the dead band. , Within the dead band, otherwise outside the dead band.

Step 145 As a result of this check, if the target torque deviation is within the dead band, the program returns to the main routine without executing the program.
Process.

Step 146 The PID nonlinear control section 67 calculates the load torque that is currently being generated for each of the electric wheels 20, 20,... Based on the voltage output from the signal processing section 87. That is, as shown in FIG. 5, the signal processing unit 87 receives a signal from the electric power control unit 75 for supplying electric power to the motor 2 of the electric wheel 20 from the motor 2.
The effective value of the applied voltage and the effective value of the supplied current are inputted, and a voltage proportional to the pulse frequency outputted from the magnetic pole position detecting element 85 in accordance with the rotation of the motor is output. The effective value of the voltage from the / V converter 86 is input, and the signal processing unit 87 performs a collective processing of these voltage values or current values, and performs a PID nonlinear control using a signal relating to the load torque of the motor 2 as a voltage value. Output to the unit 67. Therefore, the PID nonlinear control section 67 calculates the load torque based on this voltage. In addition,
This calculation of the load torque is also performed by looking up a data table in which the relationship between the voltage and the load torque is stored in advance, as described in step 143. Further, the PID nonlinear control section 67 sets a route of feedback control for performing a nonlinear correction operation at the time of acceleration, and the control at the time of acceleration is performed by this route of feedback control.

Step 147 The PID nonlinear calculation section 67 calculates a deviation between the target torque calculated in Step 143 and the load torque calculated in Step 146. The calculation of this deviation is only a simple subtraction.

Step 148 The PID nonlinear calculation unit 67 is set in advance so that the torque deviation calculated in the previous step does not change sensitively to a slight operation of the accelerator or the brake pedal, similarly to the above-described check of the dead zone in step 144. A check is made to see if it is within the dead band. That is, a change in the torque deviation is not caused by a slight change in the amount of depression of the accelerator pedal 47 and the brake pedal 48 during traveling, and the driving feeling is improved.

Step 149 The PID nonlinear calculation section 67 calculates a voltage value corresponding to the torque deviation calculated in step 147, that is, a voltage value to be applied to each of the electric wheels 20, 20,. At this time, the output voltage is subjected to an integration process, and a voltage corresponding to the torque deviation is not directly applied to each of the electric wheels 20, 20,. It has become so.

Step 150 When the voltage value to be applied to each of the electric wheels 20, 20,... Is calculated by the PID nonlinear control unit 67 up to the previous step, the supply voltage control unit 72 inputs the calculation result, and based on this voltage value, Calculation to determine which of the taps of the battery group 76 should be switched. For example, if it is necessary to apply a voltage of 65 V to a certain electric wheel 20 in order to generate a torque required for acceleration, as described above, the battery group 76
Since multiple batteries that output a voltage of 12V are connected in series, it is necessary to select a 72V tap larger than this required voltage to obtain this 65V voltage . The process of adjusting this voltage to 65 V is performed by a pulse width calculation described later.

Step 151: The supply voltage control unit 72 outputs the result of the tap position calculation to the pulse train generating unit 73 and the tap switching unit 77, and the pulse train generating unit 73 switches to the tap based on the result of the tap position calculation. Then, a pulse width calculation is performed to adjust the voltage output from the battery group 76 to the voltage required to generate the torque required for acceleration. For example, as described above, if it is necessary to apply a voltage of 65 V to a certain electric wheel 20 to generate the torque required for acceleration, a voltage of 72 V is supplied from the battery group 76 as described above. That is, in order to obtain the voltage of 65 V, the voltage of 72 V is chopped, and the voltage is obtained by controlling the energizing time to the electric wheel 20. That is, the pulse width calculation is, in other words, calculating this energization time.

Step 152 The tap switching unit 77 switches the taps of the battery group 76 to the positions calculated in step 150. When switching the taps, a motor such as a pulse motor for driving the taps is used.When the taps are switched, the voltage applied to the power control unit 75 may change rapidly. A masking signal is output from the supply voltage control unit 72 so as not to cause a spark or the like even if it occurs.

Step 153: The pulse train generation unit 73 determines, based on the pulse width calculation result calculated in step 151, the supply voltage control unit 72 to determine the ON level within one pulse of the fundamental frequency determined by the clock signal, The pulse width modulated basic clock is output to the gate control unit 74. Then, the gate control unit 74 determines the rectification timing direction for each magnetic pole polarity of the motor 2 based on the pulse width modulated basic clock and the signal related to the rotation direction output from the rotation direction determination unit 71. , This timing was controlled
The PWM signal is output to the power control unit 75. Next, the power control unit 7
5 chops the voltage applied by the battery group 76 based on the PWM signal output from the gate control unit 74 and applies the voltage after pulse width modulation to the coil of the motor 2. The power control unit 75 uses a large number of power transistors, and controls the ON time of the power transistor by the PWM signal so that the effective value of the voltage applied to the motor 2 is controlled. Has become. The voltage after this control is referred to as the motor U phase, V
Output for each phase. This allows each electric wheel 20,2
0,... Are rotated at a predetermined rotation speed.

Step 154: The gate control unit 74 and the F / V converter 86 provide the magnetic pole position detecting element 85 that outputs a pulse at each predetermined rotation angle of the motor 2.
The pulse output from is input. And the F / V converter 8
A voltage corresponding to the pulse frequency is output from 6, and this voltage is input to the signal processing unit 87.

Step 155 The signal processing unit 87 inputs the current supplied to each of the electric wheels 20, 20,... Detected by the current detector provided in the power control unit 75.

Step 156 Similarly, the signal processing unit 87 inputs the voltage of the battery supplied to the power control unit 75.

Step 157: The PID non-linear control unit 67 outputs the voltage related to the rotation speed of the motor 2 output from the signal processing unit 87 via the F / V converter 86,
The voltage supplied to each of the motorized wheels 20, 20,... Detected by the current detector and calculated based on the voltage of the battery is sampled at regular time intervals. Based on this, an estimation calculation of the load torque calculated in step 146 is performed. That is, a kind of feedforward control related to the load torque is performed.

Step 158 The PID nonlinear control section 67 determines whether or not the target torque and the load torque have become equal. As a result of this decision,
If the target torque is equal to the load torque, it is not necessary to perform the acceleration processing as described above, so the process proceeds to step 160, and if the target torque and the load torque are not yet equal, the process returns to step 140, where the target torque and the load torque are This acceleration processing will be performed until they become equal.

Step 159 Since it is determined in step 158 that the target torque and the load torque have become equal, a process for maintaining the generation of the current load torque is performed, and the process returns to the main routine.

As described above, in the acceleration processing, the selection of the tap of the battery group 76 and the pulse width control are performed so that the acceleration requested by the driver is performed, and the respective electric wheels 20, 20,. The obtained voltage is applied, and the required torque is output from each of the electric wheels 20, 20,... At a desired rotation speed.

FIGS. 16A and 16B show a flowchart for decelerating the electric vehicle, that is, a detailed flowchart of the deceleration process. This deceleration process is a process that is frequently performed during the travel of the electric vehicle, as in the acceleration process described above, and is an important process that has a significant effect on the traveling feeling. Hereinafter, this processing will be described.

Step 170: The PID nonlinear control section 67 receives the voltage output from the θ-V converter 52 by operating the accelerator pedal 47. In other words, the acceleration torque (+ value) based on the operation amount of the accelerator pedal 47 is calculated.

Step 171 Next, the PID nonlinear control section 67 receives the voltage output from the θ-V converter 53 by operating the brake pedal 48. In other words, the deceleration torque (-value) based on the operation amount of the brake pedal 48 is calculated.

Step 172 The PID nonlinear controller 67 calculates the difference between the voltage output from the θ-V converter 52 and the voltage output from the θ-V converter 53. If this difference is a negative value, it means that the driver has requested the electric vehicle to decelerate.

Step 173 The PID nonlinear control section 67 calculates the required deceleration torque, that is, the target torque, based on the voltage difference calculated in the previous step. This calculation is performed by looking up a data table in which the relationship between the voltage and the torque is stored in advance.
That is, when the voltage is V10, the target torque is T10, and when the voltage is V20, the torque corresponding to the voltage closest to that voltage is selected as the target torque from the data T20. Will do.

Step 174 The PID nonlinear control section 67 checks whether or not the target torque determined in the previous step is within a preset dead band so as not to change sensitively to a slight operation of the accelerator or the brake pedal. That is, a play is provided between the accelerator pedal 47 and the brake pedal 48. Since this check has been described above, the description is omitted here.

Step 175 If the result of this check is that the target torque deviation is in the dead band, the process returns to the main routine without executing the subsequent processing, and if it is outside the dead band, step 176 is processed.

Step 176: The PID non-linear controller 67 calculates the load torque currently generated in each of the electric wheels 20, 20,... Based on the voltage output from the signal processor 87. That is, as shown in FIG. 5, an effective value of the voltage applied to the motor 2 from the power control unit 75 for supplying power to the motor 2 of the motor-driven wheel 20 is supplied to the signal processing unit 87. And the effective value of the current from the F / V converter 86 which outputs a voltage proportional to the pulse frequency output from the magnetic pole position detection element 85 in accordance with the rotation of the motor 2. The value is input, and the signal processing unit 87 performs a collective processing of these voltage values or current values, and outputs a signal relating to the load torque of the motor 2 to the PID nonlinear control unit 67 as a voltage value. Therefore, the PID nonlinear controller 67 calculates the load torque based on this voltage. In this case, since the vehicle is about to be decelerated, the load torque naturally takes a negative value. The calculation of the load torque is also performed by looking up a data table in which the relationship between the voltage and the load torque is stored in advance, as described in step 173. Further, the PID nonlinear control section 67 sets a route of feedback control for performing a nonlinear correction calculation at the time of deceleration, and the control at the time of deceleration is performed by the route of the feedback control. A feedback gain is set in this feedback route, and when this gain is large, deceleration is performed rapidly. Therefore, setting of this gain is an important factor to make the driving feeling comfortable. .

Step 177: The PID nonlinear calculation section 67 calculates a deviation between the target torque calculated in step 173 and the load torque calculated in step 176. The calculation of this deviation is only a simple subtraction.

Step 178 The PID non-linear calculation unit 67 is set in advance so that the torque deviation calculated in the previous step does not change sensitively to a minute operation of the accelerator or the brake pedal, similarly to the above-described check of the dead zone in step 174. A check is made to see if it is within the dead zone. That is, a change in the torque deviation is not caused by a slight change in the amount of depression of the accelerator pedal 47 and the brake pedal 48 during traveling, and the driving feeling is improved.

Step 179 The PID nonlinear calculation section 67 calculates a voltage value corresponding to the torque deviation calculated in step 177, that is, a voltage value to be applied to each of the electric wheels 20, 20,. At this time, the output voltage is subjected to an integration process. A voltage corresponding to the torque deviation is not directly applied to each of the electric wheels 20, 20,... The reduced voltage is applied.

Step 180 When the voltage value to be applied to each of the electric wheels 20, 20,... Is calculated by the PID nonlinear control unit 67 up to the previous step, the supply voltage control unit 72 inputs the calculation result, and based on this voltage value, Calculation to determine which of the taps of the battery group 76 should be switched. For example, if it is sufficient to apply a voltage of 65 V to a certain electric wheel 20 to generate a torque required for deceleration, as described above, the battery group 76
Since multiple batteries that output a unit voltage are connected in series, to charge the battery group 76 with this 65V voltage, select a tap less than this required voltage of 60V or less. Will need to be done. That is, the electric vehicle performs regenerative braking. The above-described process for charging is performed by a pulse width calculation described later.

Step 181: The supply voltage control unit 72 outputs the result of the tap position calculation to the pulse train generating unit 73 and the tap switching unit 77, and the pulse train generating unit 73 switches to the tap based on the result of the tap position calculation. , A pulse width calculation for charging the battery group 76 with the voltage generated from each of the electric wheels 20, 20,... Is performed. For example, as described above, when 65 V is generated from a certain electric wheel 20 to generate the deceleration torque required for deceleration, as described above, the battery group
Although only 60V voltage will be supplied from 76, chopping the 65V voltage output from the electric wheel 20 and supplying extra voltage to the battery group 76 to obtain the electromagnetic braking effect Has become. That is, regenerative braking is performed. In this case, since it is necessary to cause the power control unit 75 to perform power regeneration, the instruction to the pulse train generation unit 73 is the reverse of the process at the time of acceleration. That is, the instruction is such that a current flows from the electric wheel 20 to the battery group 76.

Step 182 The tap switching unit 77 switches the tap of the battery group 76 to the position calculated in step 180. When switching the taps, a motor that drives the taps, such as a pulse motor, is used.When the taps are switched, the voltage supplied from the power control unit 75 may change suddenly. A masking signal is output from the supply voltage control unit 72 so as not to cause a spark or the like even if it occurs.

Step 183: Based on the pulse width calculation result calculated in step 181, the pulse train generation unit 73 determines that the supply voltage control unit 72 determines an on-level section within one pulse of the fundamental frequency determined by the clock signal. The pulse width modulated basic clock is output to the gate control unit 74. Then, the gate control unit 74 determines the voltage input timing for each magnetic pole polarity of the motor 2 based on the pulse width modulated basic clock and the signal related to the rotation direction output from the rotation direction determination unit 71. , This timing was controlled
The PWM signal is output to the power control unit 75.

Step 184 Next, the power control unit 75 chops the voltage supplied to the battery group 76 based on the PWM signal output from the gate control unit 74 and applies the pulse-width-modulated voltage output from the coil of the motor 2. . The power control unit 75
Uses a large number of power transistors, and the effective value of the voltage applied from the motor 2 to the battery group 76 is controlled by controlling the ON time of the power transistor by the PWM signal.
As a result, the power control unit 75 outputs the voltage output from the U-phase, V-phase, and W-phase of the motor to the battery group 76, and performs regenerative braking to apply predetermined braking to each of the electric wheels 20, 20,. It will give torque.

Step 185: The supply voltage control section 72 determines whether the tap position selected by the tap switching section 77 has been moved to the lowermost position as the rotational speed of the electric wheel 20 decreases due to the continuous operation of the brake pedal 48. Make a decision. That is, it is determined whether or not the current control unit 75 and the battery group 76 are connected with the minimum voltage obtained by switching the tap. If the result of this determination is not the bottom row,
Proceed to 170 and continue the above processing.
Proceed to the next step.

Step 186 Since the tap position is set at the bottom, regenerative braking cannot be performed efficiently, and thereafter the electric vehicle is stopped only by mechanical braking. In other words, the braking force is applied by the mechanical braking action and the electromagnetic braking action in the range where regenerative braking can be performed by the operation of the brake, and the braking force only by the mechanical braking action in the range where regenerative braking cannot be performed. Is given.

In this way, when the electric vehicle decelerates, the surplus power accompanying the deceleration is converted into electric power by the power generation action of each of the electric wheels 20, 20,..., And the electric power is regenerated to return the electric power to the battery. And contribute to the effective use of energy.

Although a specific flowchart is not shown, if neither the accelerator pedal nor the brake pedal is operated during traveling, that is, if the vehicle is in an operating state corresponding to a conventional engine brake, the torque during the above-described deceleration processing Since the deviation naturally becomes 0, the output voltage from the PID nonlinear control unit is also 0, and the electric power output from each electric wheel 20 is returned to the battery.

As described above, in the electric vehicle shown in the present embodiment, since the electric wheel 20 has a special structure as described above, the motor can be removed from the outside, and therefore, maintenance of the inside of the motor and the like can be easily performed. In addition, since the motor is structured to directly contact the outside air, the cooling efficiency is good and the size can be reduced as compared with a motor having the same output. And, since the output torque and the steering angle of each wheel are independently controlled, this electric vehicle can easily provide various running characteristics, and can be provided with a conventional electric vehicle or a vehicle using an engine. Can provide incomparable mobility or operability. Further, with regard to this operability, since each wheel can be controlled independently, there is a unique merit that the operability can be easily set only by changing the program.

[Effects of the Invention] As is clear from the above description, according to the control device for an electric vehicle of the present invention, the driving mode selecting means
The normal mode, the skew mode, and the rotation mode can be selected. When the normal mode is selected, the vehicle can be driven in the same manner as a normal car by operating a steering wheel, and the skew mode is selected. In this case, the vehicle can be driven diagonally by operating the steering wheel, and when the rotation mode is selected, the vehicle can be rotated on the spot. Therefore, an extremely convenient electric vehicle can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of an electric vehicle on which an electric vehicle control device according to the present invention is mounted, FIG. 2 is a detailed configuration diagram of a motorized wheel shown in FIG. 1, and FIG. FIG. 4 is a schematic perspective view of a steering device system controlled by a control device for an electric vehicle according to the present invention; FIG. 4 is a schematic configuration diagram around a control device for the electric vehicle according to the present invention; FIG. 6 is a block diagram of a portion for controlling the torque of the electric wheels in the control device of the vehicle, FIG. 6 is a block diagram of a portion for controlling the steering angle of the electric wheels in the control device for the electric vehicle according to the present invention, FIG. FIG. 8 is a flowchart showing a subroutine relating to a start-up check in the main flowchart shown in FIG. 7, and FIG. 9 is a main flowchart shown in FIG. Char FIG. 10 is a flowchart showing a subroutine relating to sensor abnormality determination, FIG. 10 is a flowchart showing a subroutine when the operation mode in the main flowchart shown in FIG. 7 is set to neutral, FIG. 12A and 12B are flowcharts showing a subroutine in the case where the operation mode in the main flowchart shown is set to parking. FIGS. 12A and 12B show a case where the operation mode in the main flowchart shown in FIG. 13 (A) and (B) are flowcharts showing a subroutine when the operation mode in the main flowchart shown in FIG. 7 is set to the rotation mode, and FIG. 14 (A) ) And (B) show the operation in the main flowchart shown in FIG. 15A and 15B are flowcharts showing a subroutine of a common acceleration process in each process, and FIGS. 16A and 16B are flowcharts showing a subroutine when the rotation mode is set to the normal mode. ) Is a flowchart showing a subroutine of a common deceleration process in each process, FIG. 17 is a top view showing the structure of a conventional electric vehicle, and FIG. 18 is a side view showing the structure of a conventional electric vehicle. 1 ... battery, 2 ... motor, 4 ... control device,
5 ... tire, 11 ... wheel, 12 ... hollow knuckle,
20 ... wheel, 30 ... rotor, 35 ... stator, 40
…… Steering actuator (steering means), 45 …… Handle, 46 …… Operation mode switching lever, 47 …… Accelerator pedal, 48 …… Brake, 49…
53 θ-V converter, 54 θ-S converter, 60 central processing unit (steering angle calculation means, torque calculation means), 100
... Control device (steering angle calculation means, torque calculation means).

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Susumu Kamio 1-1-1, Edamitsu, Yawatahigashi-ku, Kitakyushu-shi, Fukuoka Prefecture Inside Nippon Steel Corporation 3rd Technology Research Institute (72) Inventor Hiroshi Sakurai Kawasaki-shi, Kanagawa 1618 Ida, Nakahara-ku New Research Institute, Central Research & Development Headquarters, Nippon Steel Corporation (72) Inventor Masao Ono 4428 Shinyoshida-cho, Kohoku-ku, Yokohama-shi, Kanagawa Pref. Tokyo R & D Development Laboratory Co., Ltd. (56) References JP-A-63-133804 (JP, A) JP-A-59-141405 (JP, U) JP-A-55-67604 (JP, U)

Claims (1)

(57) [Claims] 1. A plurality of motor-driven wheels formed by attaching a rotor to a wheel on which a tire is mounted and attaching a stator for rotating and driving the wheel in cooperation with the rotor to an axle supporting the wheel. An electric vehicle provided with a steering wheel for steering the electric wheel; an operation mode selection unit for selecting an operation mode of the electric vehicle; a rotation angle detection unit for detecting a rotation angle of the steering wheel; and the operation mode selection unit. When the normal mode is selected, the steering angle of each of the electric wheels is calculated from the rotation angle of the steering wheel detected by the rotation angle detection means so that normal running can be performed. When selected, the vehicle runs diagonally according to the rotation angle of the steering wheel detected by the rotation angle detection means. Steering angle calculating means for calculating the steering angles of all the motorized wheels in the same direction, and setting each of the motorized wheels to the respective steering angle calculated by the steering angle calculating means. An electric vehicle comprising: a steering means for setting all the electric wheels to a steering angle capable of traveling on the same circumference so as to be able to rotate in place when the rotation mode is selected by the means. Control device.