JPS6158404A - Controller of electric railcar - Google Patents

Abstract

PURPOSE:To enhance the adhesion performance by comparing the intrinsic vibration frequency component in a self-excited vibration of a wheel shaft in a front drive phenomenon before a large slip occurs with the maximum allowable amplitude reference proportional to the speed of a railcar, and controlling so that the intrinsic vibration frequency component becomes constant. CONSTITUTION:When fine slips occurs at wheels, a twist self-excited vibration is generated at an axle. This vibration is detected by a torque sensor TS, and its intrinsic vibration frequency component is merely removed by a digital filter DF. It is compared by a comparator CPR with the maximum allowable amplitude reference REF proportional to the speed of a railcar of the vibration component, and the result is input through a creep controller SC to an amplifier AMP. The amplifier AMP which receives an acceleration command IP controls the gate controller of a chopper CH to control the main motor current IM so that the vibration component becomes constant, thereby controlling the tension of a main motor M.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a control device for an electric vehicle, and particularly to a structure that can maximize adhesive performance.

[Prior art]

Electric vehicles are driven by the frictional force between the wheels and the rails, so making the most of this frictional force is the basis of vehicle technology. FIG. 1 is a characteristic diagram showing the relationship between the friction coefficient and sliding speed between wheels and rails, and the value of the friction coefficient itself varies widely depending on the surface condition of the rail, weather, running speed, etc. (Wheel tensile force/axle load) is shown in Figure 1 P
If the coefficient of friction at a point (called the coefficient of adhesion) is exceeded, a large slip will occur, causing mechanical damage to rotating parts such as the main motor, gears, raceway surfaces, and wheel treads, as well as reducing the tensile force. The major challenge is to prevent this and to operate the vehicle as close to point P as possible. In general, the area where the slip speed is below point P is called the micro-slip, or creep area, and the area above point P is called the slip area. By the way, in the past, the so-called post-slip process involves detecting the occurrence of slip and then reducing the tensile force. A control system was used.

FIGS. 2 to 4 show a slip detection method in a conventional electric vehicle control device. These are explanatory diagrams showing the voltage comparison method, current comparison method, and speed generator method, respectively, and the detection sensitivity, processing, and problems of each method are compared. Although there are slight differences in detection sensitivity depending on the slip detection method, in both cases the detection is performed after the slip has occurred, that is, in the slip region, so the first
This method detects idling near the 8 point in the figure, lowers the tensile force to the 8 point, and re-adhes it, and is used in an area where the practical adhesive coefficient is relatively low, resulting in the following drawbacks.

That is, in an electric locomotive, the production cost increases due to the need to increase the number of moving axles, and if the number of moving wheels is kept constant, the toe side load becomes smaller.

And, in the case of trains, one train (electric vehicle/accompanying vehicle)
In other words, the proportion of electric vehicles increases, resulting in higher production and maintenance costs.

[Summary of the invention]

This invention was made in order to eliminate the drawbacks of the conventional ones, and it detects the natural vibration frequency component of the self-excited vibration of the wheel set during the precursor phenomenon before the occurrence of a large slip, and calculates this natural vibration frequency component. By controlling the tensile force of the electric motor so that the above-mentioned natural vibration frequency component becomes constant by comparing it with the allowable maximum amplitude standard proportional to the vehicle speed,
The object of the present invention is to provide a control device for an electric vehicle that can maximize adhesive performance while allowing slight slippage.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 5 is a control block diagram of a control device for an electric vehicle in an embodiment to which the present invention is applied. In the figure, ('P
an) is a pantograph, ((H) is /〈ntagraph (,
The chopper circuit controls the DC input from the trolley (BG) and supplies the DC current to the main motor (TM) built into the bogie (BG), and the (TS) detects the self-excited vibration of the wheel shaft of the bogie (BG). The torque sensor (TG) is a speed generator built into the bogie (BG) and outputs a signal proportional to the speed of the vehicle. (DF) is a digital filter circuit that extracts only the natural vibration frequency component as a slip precursor phenomenon from the self-excited vibration detected by the torque sensor ('I'S).

A digital filter circuit (DF) has an amplifier (not shown) installed at its input to pass a frequency band within a predetermined range, and the natural oscillation frequency is digitally processed using a microprocessor. The signal processing time is approximately 1 ms, which enables extremely fast signal processing. A vibration detection device (VS) is configured by a torque sensor (TS) and a digital filter circuit (DF). (C!PR) is the maximum allowable amplitude standard (As) that is proportional to the vehicle speed, which is the sum of the maximum allowable amplitude standard (As) of the natural vibration frequency component and the speed signal detected by the speed generator (TG,). REF) and digital filter circuit (DF
), (SC) is a comparator that compares the output from the comparator (
The creep controller (AMIl) receives the output from the creep controller (SC) and outputs a control signal to control the amount of creep.
) and the main motor current (IM) detected by a DC transformer (DCOT), and outputs a gate signal to the chopper circuit (OH). And the chopper circuit (
OH), permissible maximum amplitude standard (RE) proportional to vehicle speed.
F), a comparator (CPR), a creep controller (SC), and an amplifier (AMP) constitute a chopper control device (TMC) as a motor control device.

The natural vibration frequency of the above-mentioned self-excited vibration of the wheel axle is determined by the torsion spring stiffness constant of the torsion spring of the drive system and the torsion spring system of the axle, and FIG. 6 shows an example of this. That is, FIG. 6(a) shows the frequency characteristics of the amplitude of self-excited vibration based on the simulation result when the sliding speed is X, and in this example, the natural vibration frequencies are F, E[z. As the sliding speed increases from X to y in the creep region, it can be seen that the amplitude increases in proportion to the sliding speed, as shown in the figure (bl).

It is clear that the above swing width is proportional to the vehicle speed.

Next, the operation of the control device for an electric vehicle as an embodiment of the present invention configured as described above will be explained.

The main electric motor (TM) built into the wheel axle device of the bogie (BC)
) drives the axle, but when a slight slip occurs in the wheel, torsional self-excited vibration occurs in the axle. The natural vibration frequency component of this self-excited vibration increases as the sliding speed increases as shown in Figure 6.The natural vibration frequency component of the self-excited vibration increases as shown in Figure 7. , increases almost in proportion to the vehicle speed. Therefore, the torque sensor (TS) detects the above self-excited vibration, and from this, the digital filter circuit (D F ) extracts only its natural vibration frequency component. The allowable maximum amplitude standard (RE) which is proportional to the vehicle speed I of the corresponding vibration component
F) is compared by a comparator (CPR) and the result is input to the amplifier (Ba) via the creep controller (SC). Then, the amplifier (A) receives the acceleration current command (IP).
MP) controls the gate control circuit of the chopper circuit (C!H), and controls the traction motor current command (IP) so that the vibration component is maintained near the Q point in Figure 1 (the corresponding value). Controls the pulling force of the traction motor (TM).

As described above, in one embodiment of the present invention, the electric vehicle is operated at the sliding speed vS at point Q in FIG. Regardless of the coefficient of friction between the wheels and the rail, it is possible to use a value that is close to the maximum friction coefficient between the wheels and the rails, so in the case of electric locomotives, it is possible to reduce the number of moving axles (for example, from 6 moving axles to 4 moving axles). It is possible to significantly reduce the production cost of electric locomotives (can be reduced to 100%) and save resources, and by increasing the capacity of single machines such as the main motor, it is possible to save energy by improving efficiency.Furthermore, in the case of electric trains, By improving the adhesion coefficient, it is possible to reduce the proportion of electric vehicles in each train, resulting in significant initial investment and resource savings, as well as energy savings and maintenance cost reductions by reducing train weight. 〇Figure 8 is a control block diagram of a control device for an electric vehicle in another embodiment to which the present invention is applied, in which the chopper circuit (CEP) in Figure 5 is replaced by a main transformer (M'l') and its 2nd embodiment. A thyristor bridge circuit (THE) connected to the next side is adopted, and the maximum allowable amplitude standard (THE) is proportional to the vehicle speed.
EF), comparator (CPR), creep controller (8
0) and an amplifier (AMP) constitute a thyristor phase control device (TMC') as a motor control device. In this case, as an AC electric vehicle, the same effects as in the above embodiment can be achieved.

Figure 9 shows the digital filter circuit (DF) in Figure 5 combined with an analog filter circuit (AF) and a detection circuit (1) ET).
In this embodiment, the torque sensor ('I's) detects the natural vibration frequency component of the self-excited vibration of the wheel set.

Figure 10 shows the digital/I/filter circuit (DF
) to the analog filter circuit (AF) and detection circuit (DET
), which detects the natural vibration frequency component of the self-excited vibration of the wheel set using a torque sensor (TS).

In the embodiments shown in FIGS. 9 and 10 as well, 1 the amplitude of the natural vibration frequency component is compared with the permissible maximum amplitude reference (REF) proportional to the speed of the vehicle so that the natural vibration frequency component becomes constant. To provide a control device for an electric vehicle that can maximize adhesive performance while allowing slight slippage by controlling the tensile force of a main electric motor (TM).

FIG. 11 shows another embodiment of the present invention in which a thyristor variable voltage variable frequency control device (TMO) using a variable voltage variable frequency control circuit (VVVF) is applied as a motor control device. TM) as 8
A control device for an electric vehicle using a phase squirrel cage induction motor is provided.

〔Effect of the invention〕

As explained above, this invention detects the natural vibration frequency fraction of the self-excited vibration of the wheel set during the propulsive phenomenon before a large slip occurs, and converts this natural vibration frequency fraction into the allowable maximum vibration proportional to the vehicle speed. The tensile force of the Flea ζ motor is controlled so that the above-mentioned natural vibration frequency component is constant compared to the width standard, so it is possible to utilize a coefficient of friction that is almost close to the maximum coefficient of friction between the train and the rail. This has the effect of maximizing performance.

[Brief explanation of drawings]

Fig. 1 is a characteristic diagram showing the relationship between the friction coefficient and sliding speed between the wheels and the rail, and Figs. 2 to 4 are the voltage comparison method, which is the full width detection method in the conventional electric vehicle control device, respectively. An explanatory diagram showing a current comparison method and a speed generator method, FIG. 6 is a control block diagram of a control device for an electric vehicle in an embodiment of the present invention, and FIG. 6 shows a frequency characteristic of the amplitude of self-excited vibration. The characteristic diagram shown in Figure 7 is a characteristic diagram showing the relationship between the vehicle speed and the amplitude of the natural vibration frequency component, and Figures 8 to 1 are
FIG. 1 is a control block diagram of a control device for an electric vehicle in other different embodiments of the present invention. In the figure, (TM) is the traction motor, (V
S) is a vibration detection device, (REF) is a permissible maximum amplitude reference proportional to vehicle speed, and (TMC) is a motor control device. Note that the same reference numerals in the drawings indicate the same or similar parts.

Claims (7)

[Claims] (1) A vibration detection device that detects the natural vibration frequency component of the self-excited vibration of a wheel axle driven by an electric motor and outputs a vibration detection signal, and a permissible maximum of the vibration detection signal and the natural vibration frequency component proportional to the vehicle speed. A control device for an electric vehicle, comprising a motor control device that controls the tensile force of the electric motor so that the natural vibration frequency component becomes constant by comparing it with a swing width reference. (2) The vibration detection device includes a torque sensor that is attached to the wheel axle and detects the self-excited vibration of the wheel axle and outputs a detection signal, and a vibration detection device that inputs the detection signal and extracts the natural vibration frequency component of the self-excited vibration. 2. The control device for an electric vehicle according to claim 1, further comprising a filter circuit that outputs a filter circuit. (3) The control device for an electric vehicle according to claim 2, wherein the filter circuit is a digital filter circuit. (4) Claim 2, characterized in that the filter circuit is composed of an analog filter circuit and a detection circuit.
A control device for an electric vehicle as described in Section 1. (5) Claims 1 to 4, characterized in that the motor control device is a chopper control device that controls the tensile force of the motor by controlling the current of the motor using a chopper circuit. A control device for an electric vehicle according to any one of the above. (6) The motor control device is a thyristor phase control device that controls the tensile force of the motor by controlling the current of the motor using a thyristor bridge circuit. The control device for an electric vehicle according to any one of Item 4. (7) The motor control device is a thyristor variable voltage variable frequency control device that controls the tensile force of an 8-phase squirrel cage induction motor, according to any one of claims 1 to 4. electric car control device.