JP2547792B2 - Electric vehicle control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Industrial field of application) The present invention relates to an electric vehicle driven by an electric motor, in which re-adhesion control is performed when idling or sliding occurs between a driving wheel and a rail of the electric vehicle. The present invention relates to a control device for an electric vehicle.

(Prior Art) Rotational force (torque) by a motor on wheels rolling on rails
In an electric vehicle that propels the vehicle by using the rotational force as a propulsive force due to the adhesive force between the moving wheel and the rail, when the rotational force exceeds the adhesive force, the moving wheel idles on the rail. Transmission of propulsion is significantly reduced. When this phenomenon occurs during driving, it is called "idling", and when it occurs during braking, it is called "sliding". Hereinafter, a description will be given of idling, but the same applies to gliding, and therefore the description thereof will be omitted.

As described above, idling occurs when the rotational force exceeds the adhesive force, but the same applies when the adhesive force falls below the rotational force.
The adhesive force F of one wheel is F = μW (1) where μ is the adhesion coefficient and W is the weight applied to the wheel. It is known that the adhesion coefficient μ is not constant, changes when the rail track becomes a curve, or moves uphill or downhill, and is generally smaller than the adhesion coefficient of a flat and straight track. Strictly speaking, for example, in the case of an uphill slope with an angle θ, the equation (1) is F = μcos θ · W (2), and therefore μcos θ can be considered as an equivalent adhesion coefficient. The same goes for downhills. In addition, even on a flat and straight track, there are some railroad sections where the adhesion coefficient is reduced due to wear of the rail itself. Similarly, the adhesion coefficient also decreases in railroad sections with railroad crossings and points. The above is an example of the case where the adhesion coefficient decreases, but there may be other factors that decrease the adhesion coefficient depending on the property of the rail surface and the condition of the track. In any case, if the adhesion coefficient decreases, the adhesion will decrease according to the formula (1),
As a result, when the adhesive force falls below the rotational force, idling occurs.

When idling occurs, first of all, the smooth transmission of the driving force cannot be carried out, but in addition to this, secondary problems such as separation of the tread of the driving wheel, burnout of the bearing, fatigue and wear of the rail also occur. Therefore, it is necessary to get out of the idling state as quickly as possible and secure the adhesion between the driving wheel and the rail. Re-adhesion is the process of changing from the idling state to the re-adhesion state, and control of re-adhesion is called re-adhesion control.

Here, a conventional example of re-adhesion control is shown, and its problem is suitable. FIG. 5 is a general control block diagram of an electric motor drive system in an electric vehicle. As shown in the figure, a current control loop is configured to give a current command to control the torque of the electric motor to control the driving force of the electric vehicle. In the figure, 1 is a pattern generator of the current command, 2 is a comparator for calculating the deviation between the current command and the detected actual motor current, and 3 is the deviation based on an appropriate control logic using this deviation. The converter 4, which outputs a control signal to the converter 4, drives and controls the electric motor 5 based on the control signal from the current controller. The detector 6 detects the electric motor current and feeds it back to the comparator 2. 7
Is a slip / skid detector.

When the readhesion control is performed by this electric motor control system, for example, the following is performed. That is, the readhesion control current pattern shown in FIG. 6 is given as a current command. In FIG. 6, A
It is assumed that the occurrence of slippage at a point has been detected by the slip / slide detector of 7 with appropriate logic. In response to this idling detection, the current command is rapidly reduced to a predetermined ratio (50% as an example in FIG. 6) than the current command before causing idling, and re-adhesion is measured. While idling is detected, this value is held as indicated by BC in the figure. Even if the readhesion is successful and the idling is no longer detected, this value may be held for an extra predetermined time to ensure the readhesion. After that, the current command is increased relatively slowly as indicated by CD in the figure, and is smaller than the current command before the idling by a predetermined ratio (90% in FIG. 6 as an example). Return to current command. After that, as indicated by DE in the figure, this command value is held for a predetermined time, and if idling does not occur again during that time, the current command before idling is restored.

(Problems to be Solved by the Invention) The current pattern shown in FIG. 6 as an example in the conventional control method is changed or modified according to the property of the rail surface where the adhesion coefficient decreases and the state of the track. I didn't do it. Therefore, the current pattern is determined irrespective of the property of the rail surface or the state of the track, and therefore is not always a current command suitable for the property of the rail surface or the state of the track, and proper re-adhesion control is always performed. It was hard to say that Even with other control methods, the control parameters and control patterns were not changed or modified according to the properties of the rail surface and the state of the track, so it was hard to say that proper re-adhesion control was always performed. The situation remains the same.

An object of the present invention is to provide a control device for an electric vehicle capable of performing readhesion control according to the property of a rail surface and the state of a track.

[Structure of Invention]

(Means for Solving Problems) The present invention relates to an electric motor control means for controlling a drive electric motor of an electric vehicle according to a command pattern, and a track state at each position on the track is stored in advance in association with each position on the track. Track state storage means, command pattern storage means for storing a predetermined plurality of command patterns for readhesion, position specifying means for specifying the position of the electric vehicle, and idling / sliding for detecting wheel slipping or sliding. The slip detection means and, when the slip / sliding detection means detects slip or slip, a track state corresponding to the position of the electric vehicle specified by the position specifying means is searched from the track status storage means, and this track status is searched. And a readhesion control means for retrieving an optimum command pattern from the command pattern storage means and giving it as a command pattern to the electric motor control means.

(Operation) In such a configuration, when the idling / sliding detecting means detects idling or sliding, the position of the electric vehicle at that time is specified by the position specifying means. The track status corresponding to the position of the electric car is searched from the track status storage means. A command pattern storage unit is searched for a command pattern for readhesion control that is optimal for this line state, and the motor is controlled by this command pattern.

(Example) Below, the Example of this invention is described with reference to drawings.

The above-mentioned factors that decrease the adhesion coefficient, namely, so-called rail surface properties and track conditions, such as track curve parts, up and down slopes, rail surface wear, railroad crossings, points, etc., can be identified if the position of the track is known. Is. That is, if the starting point for measuring the distance on a certain track is set appropriately, the distance measured from the starting point and the property of the rail surface and the state of the track correspond one-to-one. FIG. 2 shows a simple example. This figure is a plan view of the track of the electric vehicle, and it is assumed that there is a point at point A and a curved portion at points B and C. For example, if the starting point O is set at a station in the figure, the point at the point of distance OA, the distance OB and
It can be specified that each OC point has a curved portion. Therefore, if the electric vehicle measures the distance from the point O during traveling, it is possible to specify the property of the rail surface and the state of the track at the point on the track where the electric vehicle is traveling. For this, of course, the distance measured from the starting point and the properties of the rail surface and the track condition corresponding to the distance are stored in some way,
Must be searchable. If the nature of the rail surface and the state of the track at the point on the track where the electric vehicle is traveling can be specified, re-adhesion control can be performed according to that state.

FIG. 1 is a block diagram showing a control device for an electric vehicle according to an embodiment of the present invention. In the figure, the same components as those in FIG. 5 are designated by the same reference numerals and the description thereof will be omitted. In this embodiment, the microcomputer 8 is used to generate a current command, compare with a current feedback signal, execute the function of a current controller, and give a control signal to the converter 4 via an interface circuit 9. Reference numeral 10 is an interface circuit for incorporating the signal of the current detector into the microcomputer. The CPU executes normal drive control and other necessary functions in addition to the readhesion control according to the present invention.

In the memory 1, the distance from the predetermined starting point is used as an argument, and the property of the rail surface and the state of the track (referred to as a line state here) at the point of the distance are as shown in FIG. 3, for example. Record it in advance. At this time, as shown in the figure, characteristic values of the line state, such as the curvature of the curved portion and the slope of the slope, are also recorded. Characteristic values such as track wear, points, and railroad crossings may be appropriately graded. In the memory 2 are stored current command patterns which are the same as in FIG. 6 but are variously changed in various proportions as shown in FIG. In these current command patterns, for example, when the track condition is very slippery, as in pattern D, the current is greatly squeezed by the first slip detection, and the current command is slowly recovered even after re-adhesion. Use a pattern that does not return until. In short, various current command patterns shown in FIG. 4 are prepared according to the easiness of slipping / sliding. These patterns are control parameters that can be adjusted according to the magnitude of the above-mentioned adhesion coefficient. When the above data is actually recorded in the memory of the microcomputer, it may be encoded appropriately. The correspondence relationship between the line status and the current command pattern can be various combinations depending on the number of cases classified in the line status and the number of current command patterns, but it is predetermined as the current command pattern suitable for the line status. A search function that can specify The function is
In this embodiment, of course, it is programmed and executed by the CPU.

If the electric car is running, for example, does not slip / slide,
Alternatively, the distance from the starting point is calculated based on the rotational speed of the driven wheel, which is extremely unlikely to occur. When the occurrence of slipping is detected, the distance 1 is used to search the memory 1 to specify the line state. A current command pattern suitable for the line state thus identified is selected from the memory 2. The electric motor is drive-controlled based on the current command pattern.

As described above, in the embodiment of the present invention, the track condition is always grasped by the distance traveled from the starting point, and when slipping occurs, re-adhesion control can be performed with a current command pattern suitable for the track condition, so that quick re-adhesion and re-spin Re-adhesion control that does not easily occur becomes possible.

In this embodiment, the distance of the electric car is calculated from the rotation speed of the driven wheel, but any method may be used as long as the position of the electric car on the track can be specified.
For example, the position may be specified from a signal laid along the line. In Fig. 3, the distance is divided into arguments with the same step width (1 km), but the line may be divided into sections of appropriate length and used as arguments. At this time, the width of the section does not necessarily have to be uniform. For example, when a certain line state continues for a long distance, one interval may be set as the interval, and when the other line state changes for a short distance, a short section may be set according to the line state.

〔The invention's effect〕

As described above, according to the present invention, it is possible to provide a control device for an electric vehicle capable of performing readhesion control according to a track state.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention, FIG. 2 is an explanatory view showing an example of the correspondence relationship between the distance from the starting point and the line state, and FIG. 3 is a memory of the microcomputer shown in FIG. FIG. 4 is a diagram showing the correspondence between the distance in which the stored distance is expressed as an argument and the line state, FIG. 4 is a current command pattern stored in the memory, and FIG. 5 is a conventional electric vehicle control device for readhesion control. FIG. 6 is a block diagram showing the configuration of FIG. 6, and FIG. 6 is a diagram showing a current command pattern in the apparatus of FIG. 1 ... Current command pattern generator, 2 ... Comparator 3 ... Current controller, 4 ... Converter 5 ... Electric motor, 6 ... Current detector 7 ... Idling / sliding detector, 8 ... Micro Computer 9,10 ... Interface

Claims (1)

(57) [Claims] 1. A motor control means for controlling a drive motor of an electric vehicle according to a command pattern; a track state storage means for preliminarily storing a track state at each position on the track in association with each position on the track; Command pattern storage means for storing a plurality of command patterns for re-adhesion, position specifying means for specifying the position of the electric vehicle, idling / sliding detection means for detecting idling or sliding of wheels, and this idling / sliding When slipping or gliding is detected by the detection means, the track state corresponding to the position of the electric vehicle specified by the position specifying means is searched from the track state storage means, and the optimum command pattern for the track state is obtained. And a readhesion control means for retrieving from the command pattern storage main stage and giving it to the electric motor control means as a command pattern.