JP4495819B2 - Electric vehicle control device - Google Patents

Description

[0001]
[Technical field to which the invention belongs]
The present invention relates to an electric vehicle control device that realizes re-adhesion control that effectively uses adhesive force while maintaining good riding comfort of an electric vehicle.
[0002]
[Prior art]
An electric vehicle performs acceleration / deceleration by means of a tangential force between wheels and rails (also referred to as adhesive force), and this tangential force generally has a characteristic as shown by a broken line in FIG. 14 with respect to the sliding speed. . The tangential force divided by the axial weight (vertical load applied to the rail per axle) is called the tangential force coefficient, and the maximum value of the tangential force coefficient is called the adhesion coefficient.
As shown in the figure, a torque not exceeding the maximum value of the tangential force is generated with the air brake force of the main motor or a dynamic shaft mechanically coupled to the main motor in combination with the main motor torque during braking (hereinafter simply referred to as the dynamic shaft). In this case, there is no idling / sliding, and the electric car travels in a sticking area with a small sliding speed on the left side of the maximum tangential force.
[0003]
If a torque larger than the maximum value is generated, the sliding speed increases and the tangential force decreases, so the slipping speed increases and the slipping / sliding state increases.However, when the wheels and rails are dry, the torque generated by the main motor or During braking, the performance of the vehicle is set so that the combined value of the air brake force of the dynamic shaft and the main motor torque does not exceed the maximum value of the tangential force, so no idling or sliding occurs.
However, as indicated by the solid line, when the rail surface is wet due to rain or the like, the adhesion coefficient decreases and the maximum value of the tangential force becomes smaller than the torque corresponding to the set performance of the vehicle.
[0004]
In this case, the slipping speed increases and the vehicle is idling / sliding.If left as it is, the tangential force decreases correspondingly, and the acceleration / deceleration force required for accelerating / decelerating the vehicle further decreases. It is necessary to detect idling / sliding and reduce the total value of the air brake force of the moving shaft and the generated torque of the main motor at the time of braking or torque generated by the main motor, and re-adhere.
When re-adhesion is carried out by controlling the torque in this way, the maximum value of the tangential force is maximized as much as possible while suppressing the sliding speed to a small value and the sum of the torque generated by the main motor or the air brake force of the dynamic shaft and the main motor generated torque It is necessary to increase the acceleration / deceleration performance of the electric vehicle to control the value to be in the vicinity.
[0005]
As a method for realizing such re-adhesion control, the rotational speed of the main motor is detected, and this information and the calculated value or measured value of the generated torque of the main motor are used as input information for the wheel Recently, a method for estimating the tangential force coefficient between rails and controlling the torque generated by the main motor has been proposed (Reference (1): The tangential force coefficient of an electric vehicle using a disturbance observer). (Estimation method-2nd report-, IEEJ Semiconductor Power Converter Study Group, January 30, 1998).
[0006]
In addition to the tangential force coefficient using a primary disturbance observer, the differential value with respect to time of the tangential force coefficient is estimated, and a proposal to further improve the re-adhesion control performance by detecting idling / sliding faster. (Reference (2): A method for robust adhesion control of electric vehicles based on a primary disturbance observer, 1999 IEEJ Industrial Application Conference Proceedings, August 1999).
[0007]
In an actual electric vehicle, when controlling the command torque to the electric motor installed for each dynamic shaft, when the weight of the front dynamic shaft and the rear dynamic shaft of each truck is stopped, It changes from the axial weight of the. In addition, when the command torque (and thus the generated torque) changes from moment to moment, the axle load of each dynamic shaft also changes dynamically accordingly. For this reason, an estimation error due to a change in axial load occurs in the tangential force coefficient estimated using these disturbance observers. Even in such a situation, the re-adhesion control is required to constitute a stable re-adhesion control system and achieve an effective use of the adhesive force while maintaining a good riding comfort.
Of course, the control method of the above document is also aimed at realizing such a purpose, but it takes into account the dynamic behavior of the bogie and constitutes a very robust control system. Is required.
[0008]
Hereinafter, description will be given based on the drawings.
FIG. 7 is a diagram illustrating an example of a conventional re-adhesion control system configured independently for each axis, FIG. 8 is a diagram illustrating an example of a torque reduction function C (t) generated when slipping / sliding is detected, and FIG. Is a simplified diagram of the carriage, Fig. 10 is an example of a simulation result of re-adhesion control when a conventional re-adhesion control system is configured independently for each axis, and Fig. 11 is a re-adhesion control system configured for a conventional independent re-adhesion control system. FIG. 12 is a diagram showing an entire system including an adhesion control system / main motor torque control system and a carriage, FIG. 12 is an example of an impulse response of the system corresponding to FIG. 11 (when differential gain K L = 100), and FIG. An example of the impulse response of the system corresponding to 11 (when differential gain K L = 0), FIG. 14 is a diagram showing general characteristics with respect to the tangential force coefficient or the sliding speed of the tangential force.
For example, as shown in FIG. 7, there can be considered a system in which a re-adhesion control system is configured independently for each moving shaft in the carriage.
In FIG. 7, for example, for the first axis, the torque command value T PI1 for the main motor control system of the first axis (not shown) and the rotational angular velocity ωm1 of the main motor of the first axis from the encoder (not shown) are supplied to the disturbance observer 9. input. The disturbance observer 9 is assumed to be a first-order disturbance observer as shown in FIG. 2 to be described later (see reference (2)). With this observer, the estimated value of the tangential force coefficient μh1 and the estimated value of the time derivative of the tangential force coefficient μdh1 Is output to the torque command value calculator 11.
The torque command value calculator 11 obtains the first torque command value T′PI 1 according to the equation (1) and outputs it to the adder 15.
[0009]
T'PI1 = KI ・ μh1 + KL ・ μdh1 ・ ・ ・ ・ ・ ・ (1)
Here, _{K I, K L} is a gain constant.
The estimated value μdh1 of the time differential value of the tangential force coefficient is output from the disturbance observer 9 to the torque reduction function generator 13. The torque reduction function generator 13 recognizes that idling occurred when the estimated value μdh1 of the time derivative of the input tangential force coefficient is satisfied for a certain period of time for μdh1 <0 (sliding in the case of a brake) 8), a torque reduction function C (t) as shown in FIG. 8 is generated and output to the adder 15. (Hereinafter, the case of powering will be described, but the same applies to the case of braking. is there) .
Accordingly, the torque command value T PI1 for the main motor torque control system (not shown), which is the output of the adder 15, is expressed by equation (2) when no slipping is detected, and when the slipping is detected by equation (3) Sought by.
[0010]
T PI1 = KI ・ μh1 + KL ・ μdh1 ・ ・ ・ ・ ・ ・ (2)
T PI1 = KI ・ μh1 + KL ・ μdh1 + C (t) (3)
Similarly, the torque command value T PI2 for the main motor torque control system of the second axis is calculated by the disturbance observer 10, the torque command value calculator 12, the torque reduction function 14, and the adder 16 for the second axis.
As described above, when the re-adhesion control system as described above that commands the torque command value to each main motor control system independently for each axis, the following problems may occur.
[0011]
That is, FIG. 9 shows a simplified diagram of the carriage. Depending on the moment of inertia of the carriage frame 17 of the carriage and the spring constants of the shaft springs 18 and 19, the re-adhesion control system, the main motor torque control system and the carriage shown in FIG. The entire system (see Fig. 11) including the system becomes unstable, and a stable system is realized no matter how the gains of the torque command value calculators 11 and 12 of the re-adhesion control system shown in Fig. 7 are adjusted. If you can't.
[0012]
For example, if the inertia moment of the carriage frame 17 is set large as seen in the conventional carriage (for example, about 10,000 N / m), and the spring constant of the shaft spring is also set to, for example, about 6400 × 10 3 N / m, FIG. As shown in FIG. 12, the impulse response of the entire system shown in FIG. 11 when the torque command value T PI1 to the first shaft main motor torque control system is output with respect to the torque impulse input of the first shaft is shown in FIG. Thus, the result is divergent (when the differential gain K L = 100).
[0013]
FIG. 13 shows an impulse response when the differential gain K L = 0, and it can be seen that this is also a divergent system (the same applies to the second axis).
As in this example, the first axis readhesion control system as shown in FIG. 7, when configured in the second axis independently can not be a converging system the system from a divergent system (adjustment of the proportional gain K _I Is independent of the stability and instability of the control system).
[0014]
FIG. 10 shows an example of a simulation result when re-adhesion control is performed in such a system.
For the first axis in the traveling direction, the torque command value is gradually reduced even after the idling has converged, and the torque command value becomes zero. For the second axis, the torque is gradually reduced without causing idling.
In this way, the control system becomes unstable, and the adhesive force utilization rate ηt defined by Eq. (4) has become very small (the adhesive utilization rate ηt is 100%, which is the maximum utilization rate). It means)
[0015]
ηt = (dynamic axis tangential force / dynamic axis load) × 100 (%) (4)
In the bogie having parameters such as the bogie frame inertia moment and the axial spring constant as shown in the examples of FIGS. 12 and 13, when the re-adhesion control system is configured independently for each axis shown in FIG. The change in the torque generated on any of the shafts in the car triggers the swaying caused by the pitching of the carriage, and the torque command value gradually increases, causing the idling to diverge or sticking. As the torque command value becomes too small (FIG. 10 shows an example in this case), the control becomes unstable and the effective use of the adhesive force cannot be expected.
As described above, when the re-adhesion control system for each axis is configured independently as shown in FIG. 7, there is a problem that a stable control system may not be configured depending on the carriage.
[0016]
[Problems to be solved by the invention]
As described above, if the re-adhesion control system is configured independently for each axis, depending on the values of the parameters of the carriage (the inertial moment of the carriage frame, the value of the shaft spring constant, etc.) It is assumed that the entire system including the re-adhesion control system becomes unstable due to the dynamic behavior, and the effective use of the adhesive force cannot be achieved. However, it is necessary to avoid this.
[0017]
The object of the present invention is to provide a tangential force coefficient and its time using a disturbance observer in a system in which the main motor of each axis is driven by a separate power converter as described above, regardless of the value of the parameter of the carriage. The re-adhesion control system using the method for estimating the differential value is to always constitute a stable re-adhesion control system so that the adhesive force can be effectively used.
[0018]
[Means for Solving the Problems] That is, means for achieving the object are the torque command values or the calculated values of the generated torques of the two main motors, and the two main motors detected by the speed sensor. Estimated tangential force coefficient and tangential force coefficient of the driving wheel of the electric vehicle corresponding to each main motor estimated using the disturbance observer as input information to the disturbance observer corresponding to each main motor An electric vehicle control device provided with a controller for independently controlling the torque command value or generated torque of the two main motors using an estimated value of the differential value, each estimated using each of the disturbance observers wherein for calculating a torque command value to the main motor to the driving wheel of the electric vehicle corresponding estimated tangential force coefficient and tangential force of the other one another estimated value of the time differential value of the coefficient main motor Enter into your vessel calculates the torque command value to the main motor, an electric vehicle control device according to claim more by being configured so as to stabilize the re-adhesion control more.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the electric vehicle control apparatus of the present invention will be described in detail using the illustrated embodiments.
1 is a block diagram showing an embodiment of the re-adhesion control system of the present invention, FIG. 2 is a block diagram of a disturbance observer used in the embodiment of the present invention, and FIG. 3 is a simulation of re-adhesion control using the embodiment of the present invention. FIG. 4 is a diagram showing an example of the result, FIG. 4 is a diagram showing an entire system including the re-adhesion control system / main motor torque control system and the carriage of the present invention, and FIG. 5 is an example of an impulse response of the system corresponding to FIG. FIG. 6 shows an example of the impulse response of the system corresponding to FIG. 4 (when differential gain K L = 0).
[0020]
In FIG. 1, the torque command value of each of the two main motors or the calculated value of the generated torque and the rotational speed of the two main motor shafts detected by the speed sensor are input to the disturbance observer corresponding to each main motor. As information, the torque command of the two main motors using the estimated tangential force coefficient of the driving wheel of the electric vehicle corresponding to each main motor estimated using the disturbance observer and the time differential value of the tangential force coefficient An electric vehicle control device provided with a controller for independently controlling a value or generated torque,
The estimated tangential force coefficient of each dynamic axis and the estimated value of the time differential value of the tangential force coefficient are input to the controller that calculates the torque command value for the other main motor, and the torque command value for each main motor Is calculated so as to further stabilize the re-adhesion control.
[0021]
That is, the first main motor rotation speed ωm1 detected by a speed sensor (not shown) and the torque command value T PI1 to the first main motor are input to the first disturbance observer 1, and the first disturbance observer 1 The estimated value μh1 of the tangential force coefficient of one dynamic axis and the estimated value μdh1 of the time differential value of the tangential force coefficient are calculated in the same manner as described above. Then, the estimated value μh1 of the tangential force coefficient of the first moving shaft and the estimated value μdh1 of the time differential value of the tangential force coefficient are input to the torque command value calculator (controller) 4 for the second main motor. .
[0022]
Similarly, a second main motor rotation speed ωm2 detected by a speed sensor (not shown) and a torque command value T PI2 to the second main motor are input to the second disturbance observer 2, and the second disturbance observer 2 Is used to calculate the estimated value μh2 of the tangential force coefficient of the second moving shaft and the estimated value μdh2 of the time derivative of the tangential force coefficient, which are input to the torque command value calculator (controller) 3 for the first main motor. Is done.
The disturbance observer 1 is assumed to be a first-order disturbance observer as shown in FIG. 2 (the description is omitted because it is a known technique). With this observer, the estimated value of the tangential force coefficient μh1 and the time differential value of the tangential force coefficient. Is calculated and output to the torque command value calculator 4 of the second axis. The torque command value calculator 4 obtains the torque command value T′PI2 of the second axis according to the equation (5) and outputs it to the adder 8.
[0023]
T'PI2 = KI ・ μh1 + KL ・ μdh1 (5)
On the other hand, the estimated value μdh2 of the time differential value of the tangential force coefficient of the second axis estimated by the disturbance observer 2 is output from the disturbance observer 2 to the torque reduction function generator 6. The torque reduction function generator 6 recognizes that idling has occurred when the estimated value μdh2 of the time differential value of the input tangential force coefficient is satisfied for a certain period of time, and is shown in FIG. Such a torque reduction function C (t) is generated and output to the adder 8.
Therefore, the torque command value TPI2 for the second-shaft main motor torque control system (not shown), which is the output of the adder 8, is expressed by equation (6) when idling is not detected, and by equation (7) when idling is detected. Sought by.
[0024]
T PI2 = KI ・ μh1 + KL ・ μdh1 ・ ・ ・ ・ ・ ・ (6)
T PI2 = KI ・ μh1 + KL ・ μdh1 + C (t) (7)
Similarly for the first axis, the estimated value μh2 of the tangential force coefficient of the second axis estimated by the disturbance observer 2 and the estimated value μdh2 of the time derivative of the tangential force coefficient of the second axis are used as the torque of the first axis. The torque command value calculator 3 obtains the torque command value T′PI1 for the first axis according to the equation (8) and outputs it to the adder 7.
[0025]
T'PI1 = KI ・ μh2 + KL ・ μdh2 ・ ・ ・ ・ ・ ・ (8)
Then, the estimated value μdh1 of the time differential value of the tangential force coefficient of the first axis estimated by the disturbance observer 1 is output from the disturbance observer 1 to the torque reduction function generator 5. The torque reduction function generator 5 recognizes that idling has occurred when the estimated value μdh1 of the time differential value of the input tangential force coefficient is continuously satisfied for a certain period of time, and is shown in FIG. Such a torque reduction function C (t) is generated and output to the adder 7. Therefore, the torque command value T PI1 for the main motor torque control system (not shown), which is the output of the adder 7, is expressed by equation (9) when no slipping is detected, and by formula (10) when slipping is detected. Sought by.
[0026]
T PI1 = KI ・ μh1 + KL ・ μdh1 (9)
T PI1 = KI ・ μh1 + KL ・ μdh1 + C (t) (10)
Thus, when the re-adhesion control system is configured such that the estimated value of the tangential force coefficient of each axis and the time differential value thereof are input to the main motor torque command value calculator of the other axis, FIG. In the block diagram of the entire system including the re-adhesion control system, the main motor torque control system, and the carriage, the torque command value T PI1 to the first axis main motor torque control system with respect to the torque impulse input of the first axis. 4 can be a convergent system as shown in FIG. 5 (when differential gain K L = 100). Even when the differential gain K L = 0, a convergent system can be obtained as shown in FIG.
[0027]
Since the entire system can be made into a convergent system in this way, as can be seen from the simulation result of the re-adhesion control state when such a re-adhesion control system shown in FIG. It can also be understood from the utilization factor of the tangential force coefficient that the adhesive force can be effectively used.
In the above description, the embodiment has been described on the assumption that the torque command value is used. However, the same control operation can be performed even if the calculated value of the generated torque of the main motor is input to the disturbance observer instead of the torque command. Therefore, the description of the case where the calculated value of the generated torque is used will be omitted.
[0028]
【The invention's effect】
As described above, according to the present invention, the estimated value of the tangential force coefficient estimated by the disturbance observer of the first axis in the system that drives the main motors of the respective axes in the same carriage using separate power converters. And the estimated value of the time differential value of the tangential force coefficient are input to the main motor torque command value calculator of the second axis, and the estimated value of the tangential force coefficient estimated by the disturbance observer of the second axis and the time differential value of the tangential force coefficient Is input to the main motor torque command value calculator for the first axis, so that the entire system, including the re-adhesion control system and the carriage, can be changed to the parameters of the carriage (moment of inertia of the carriage frame, shaft spring constant, etc. ), A stable control system can be constructed at all times, so that the adhesive force can be effectively utilized.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an embodiment of a re-adhesion control system of the present invention.
FIG. 2 is a block diagram of a disturbance observer used in the embodiment of the present invention.
FIG. 3 is a diagram illustrating an example of a simulation result in which re-adhesion control is performed using an embodiment of the present invention.
FIG. 4 is a diagram showing an entire system including a re-adhesion control system / main motor torque control system and a carriage according to the present invention.
FIG. 5 is an example of an impulse response of the system corresponding to FIG. 4 (when differential gain K L = 100).
6 is an example of an impulse response of the system corresponding to FIG. 4 (when differential gain K L = 0). FIG.
FIG. 7 is a diagram showing an example of a conventional re-adhesion control system configured independently for each axis.
FIG. 8 is a diagram illustrating an example of a torque reduction function C (t) that is generated when idling / sliding is detected.
FIG. 9 is a simplified diagram of a carriage.
FIG. 10 is an example of a simulation result of re-adhesion control when a conventional re-adhesion control system is configured independently for each axis.
FIG. 11 is a diagram showing an entire system including a re-adhesion control system, a main motor torque control system, and a carriage that constitute a conventional re-adhesion control system for each axis.
12 is an example of an impulse response of the system corresponding to FIG. 11 (when differential gain K L = 100). FIG.
FIG. 13 is an example of the impulse response of the system corresponding to FIG. 11 (when differential gain K L = 0);
FIG. 14 is a diagram showing a general characteristic with respect to a tangential force coefficient or a sliding speed of the tangential force.
[Explanation of symbols]
1, 9 First axis disturbance observer 2, 10 Second axis disturbance observer 3, 11 Torque command value controller 4, 12 for calculating torque command value to the first axis main motor To the second axis main motor Torque command value controller 5, 6, 13, 14 for calculating torque command value for torque reduction function generator 7, 8, 15, 16 Adder
17 Bogie frame
18, 19 axis spring
20, 21 Hanging link
22, 23 Main motor
24, 25 gearbox
25, 26 Large gear
27, 32 Disturbance observer on the first axis
28, 33 Second axis disturbance observer
29, 34 Torque command value controller that calculates the torque command value for the main motor of the first axis
30, 35 Torque command value controller that calculates the torque command value for the main motor of the second axis
31, 36 Main motor torque control system and cart
37, 38, 39, 40 Adder ωm1 Main motor rotation speed of the first axis ωm2 Main motor rotation speed of the second axis
T PI1 Torque command value to the main motor of the first axis
T PI2 Torque command value to the main motor of the second axis μh1 Estimated value of the tangential force coefficient of the dynamic axis of the first axis μh2 Estimated value of the tangential force coefficient of the dynamic axis of the second axis μdh1 Tangent of the dynamic axis of the first axis Estimated force coefficient time derivative μdh2 Estimated tangential force coefficient time derivative of the second axis
C (t) Torque reduction function
Tm Torque command value ωm Angular speed of main motor
Estimated ThL load torque
TdhL Estimated time derivative of load torque μdh Estimated tangential force coefficient Time derivative μh Estimated tangential force coefficient
Jm Moment of inertia viewed from the main motor shaft
a, b constant
s Laplace operator
Rg gear ratio
W / g axle load
r Driving wheel radius

Claims (1)

As input information to the disturbance observer corresponding to each main motor, the torque command value of each of the two main motors or the calculated value of the generated torque and the rotational speed of the two main motor shafts detected by the speed sensor, Torque command values or generated torques of the two main motors using the estimated tangential force coefficient of the driving wheel of the electric vehicle corresponding to each main motor estimated using the disturbance observer and the time differential value of the tangential force coefficient In the electric vehicle control device provided with a controller for controlling each independently,
The estimated tangential force coefficient of the driving wheel of the electric vehicle corresponding to each main motor estimated using each of the disturbance observers and the estimated value of the time differential value of the tangential force coefficient are each calculated as a torque command value to the other main motor. An electric vehicle control device configured to input a controller and calculate a torque command value for each main motor to further stabilize the re-adhesion control.

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