JPS63217902A - Control system for motor for driving electric railcar - Google Patents

Abstract

PURPOSE:To easily and effectively eliminate the slip of wheels in an electric railcar by so reducing the target value of an armature current as to decrease a motor output while an unbalance exists in a magnetic field current between DC series motor groups. CONSTITUTION:If a specific wheel driven by first DC series motor group slightly slips, the armature current of the motor group in which the slip occurs decreases, and a deviation occurs between the armature current and a target current value. In order to eliminate the deviation, a current flowing to the first field winding group 12 is reduced. Thus, a difference occurs between the current of the first group and the field current of a second DC series motor group. A comparator 33 detects the difference of the field currents of the motor groups detected by field current detectors 31, 32, and applies a field current unbalance signal to a current setter 34. The setter 34 decreases the target current value by the unbalance detection signal.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is an electric vehicle driven by a group of DC series-wound motors using a field control system, and is capable of eliminating output imbalance caused by idling of some of the wheels. This invention relates to a control method for a drive motor.

[Conventional technology]

Fig. 2 is a circuit diagram showing a conventional example of an electric car driven by a group of DC series motors using a field control method, in which two sets of DC series motors each consisting of 8 DC series motors and 4 sets are shown. This is the case when electric cars are driven in groups.

In FIG. 2, a first armature group 11 consisting of a series circuit of four armatures, a first field winding group 12 consisting of a series circuit of four field windings, By connecting them in series, a first DC series motor group is formed, and similarly a second armature group 21 consisting of four armatures,
A second DC series motor group is formed by connecting a second field winding group 22 of four field windings in series, and these two groups make a total of eight DC series motors. Since wheels (not shown) are separately connected to each of the wheels, the DC power taken in from the overhead wire 2 via the pantograph 3 rotates these wheels, causing the electric car to travel.

A variable output DC power supply 13 is connected in series to the first field winding group 12, and a parallel reactor 14 is further connected in parallel to form a field circuit. A variable output DC power supply 23 is connected in series, and a parallel reactor 24 is also connected in parallel.

Electric cars generally run under constant current control. Therefore, the actual value of the armature current of the first DC series motor group is detected by the armature current detector 15, and a proportional integral calculation is performed so that this actual current value matches the current target value set by the current setting device 4. The deviation between the target current value and the actual current value is manually input to the current regulator 16, which is composed of a device. The current regulator 16 sends a control signal to the phase shifter 1 to make this input deviation zero.
Since the phase shifter 17 controls the output voltage of the variable output DC power supply 13 based on this control signal, the field current flowing through the first field winding group 12 changes and the armature current changes. Maintain the target value mentioned above. Similarly, the second DC series motor group is variable by a current regulator 26 and a phase shifter 27 so that the actual current value detected by the armature current detector 25 matches the current target value by the current setting device 4. Output DC/current power supply 23
control.

The DC series-wound motor using the field control method is either a field additive excitation method in which the variable output DC power supply 13 or 23 is connected in series with the field winding as described above, or a method in which the field of the DC belly-wound motor is controlled by a chopper or the like. There is. Therefore, we equipped a plurality of DC series motors using the field control method shown in Figure 2.
When an electric car driven by these is driving in a row, 8
All of the DC series-wound motors on the platform rotate at the same speed, but if for some reason one wheel slips, the speed of the motor driving that wheel will be higher than the others. Since the wheels that are idling do not contribute to driving the electric vehicle, the driving force of the electric vehicle decreases accordingly, which is inconvenient.

In the conventional circuit shown in FIG. 2, for example, if a wheel connected to a specific armature belonging to the first armature group 11 spins, the speed of that armature increases and the armature current decreases. . Therefore, the above-mentioned current regulator 16 and phase shifter 1
7 and the variable output DC power supply 13, the field current flowing through the first field winding group 12 is reduced, and control is performed so that the current flowing through the first armature group 11 reaches the current target value. At the same time, an attempt is made to eliminate the above-mentioned idling by reducing the output of the first DC series motor group.

[Problem that the invention seeks to solve]

By the way, as mentioned above, in order to eliminate the idling, the output of one DC series motor group is reduced, but if the idling is not completely eliminated and a slight idling state exists, the above-mentioned field The state of magnetic weakening continues, and the output of one, ie, the first DC series motor group, becomes smaller than the output of the other, ie, the second DC series motor group. That is, this electric car has a serious drawback that the capacity of the electric motor that it has is not able to be used effectively, and the driving force of the electric car is reduced.

Therefore, the purpose of this invention is to eliminate the slippage that occurs in some of the wheels of an electric vehicle driven by a DC series motor group using a field control method.Even if the output of the motor group is reduced, a small amount of slipping still remains. The purpose of the present invention is to eliminate the inconvenience that the driving force of the electric vehicle decreases due to a continuation of a state of decreased output.

[Means for solving problems]

In order to achieve the above object, the control method of this invention is as follows:
A field circuit obtained by connecting a reactor in parallel to a circuit in which a variable output DC power supply is connected in series to multiple field windings connected in series, and multiple armatures each having a wheel connected in series. A DC series motor group is formed by connecting the armature circuits formed by the above DC series motors in series, and by adjusting the output voltage of the variable output DC power supply of each of the plurality of DC series motor groups, In a control method for an electric vehicle drive motor in which the armature current of each motor group is controlled to a predetermined target value, the field current of each DC series motor group is detected separately, and the field current is If there is a difference, the aim is to reduce the target value of the armature current.

[Effect]

According to this invention, when a wheel driven by a specific motor in a group of DC series motors slips, the field current of that motor group is reduced to eliminate the slip. If the idling is not resolved, the field current will continue to decrease, that is, the output of that motor group will continue to decrease, so the difference between the field current of other normally operating DC series motor groups will be The target value of the armature current of each DC series motor group is reduced to eliminate the difference in field current, the output of all motors is reduced to eliminate the above-mentioned idling phenomenon, and then By increasing the target value of the armature current to its original value, it is possible to quickly eliminate the slip and prevent the electric vehicle from running with reduced driving force.

〔Example〕

FIG. 1 is a circuit diagram showing an embodiment of the present invention.

In FIG. 1, a first armature group 11 consisting of four armatures connected in series is connected to a first field winding group 12 consisting of four field windings connected in series. They are connected in series to form a first DC series motor group, and a variable output DC power supply 13 is connected in series to the first field winding group 12, and a parallel reactor 14 is connected in parallel. The circuit is the same as the conventional example circuit shown in FIG. 22, a variable output DC power supply 23 is connected in series and a parallel reactor 24 is connected in parallel, and DC power is supplied to these first and second DC series motor groups from the overhead line 2 via the pantograph 3. Being driven by an electric car. Note that in order to drive the electric vehicle, wheels (not shown) are coupled to each armature. Further, the current of the first armature group 11 detected by the armature current detector 15 is adjusted to the current target value set by the current setting device 34 by the action of the current regulator 16, the phase shifter 17, and the variable output DC power supply 13. A current regulator 26 controls the current of the second armature group 21, which is also detected by an armature current detector 25.
The fact that the phase shifter 27 and the variable output DC power supply 23 are used to control the current to the same target value is the same as in the conventional circuit already described in FIG.

In the present invention, a field current detector 31 that detects the field current flowing through the first field winding group 12 and a field current detector 31 that detects the field current flowing through the first field winding group 12 and the second field winding group 2
a field current detector 32 that detects the field current flowing through the
A comparator 33 that detects the difference between these two field currents, and a current setter 34 that operates to lower the target value of the armature current when the comparator 33 detects the difference are provided.

When the electric vehicle is running normally, the output voltage of the variable output DC power supplies 13 and 23 provided in each DC series motor group is such that the current of the first and second armature groups 11 and 21 is equal to the current. Since the current is controlled to match the current target value set by the setting device 34, the armature current and field current between the first and second DC series motor groups connected in parallel are Since they match, there is no imbalance in the output.

If a slight slip occurs in one of the wheels, for example, a specific wheel driven by the first DC series motor group, the armature current of the motor group that caused the slip decreases, and the current target value is reduced. In order to eliminate this deviation, the output voltage of the variable output DC power supply 13 is changed to reduce the current flowing through the first field winding group 12. Therefore, a difference occurs between the field current and the field current of the second DC series motor group which is normally operating. In other words, an unbalanced output will occur between the first and second DC series motor groups.

The comparator 33 detects a difference caused by the above-mentioned causes in the field current of each motor group detected by the field current detectors 31 and 32, and transmits a field current unbalance signal to the current setting device 34. The current setter 34 uses this unbalance detection signal to lower the current target value that it sets. Current regulators 16 and 26, phase shifters 17 and 27 and variable output DC power supplies 13 and 23 operate in such a way that the actual value of the respective armature current corresponds to this reduced current target value. The output of each DC series motor is throttled to promote readhesion of wheels during idling.

If the wheel re-adhesion is successful, the difference in field current between both DC series motor groups becomes zero, so the comparator 33
cancels the field current imbalance signal.

At this point, the outputs of both DC series motor groups are equal. Therefore, the current setter 34 returns the current target value it outputs to its original value, and each DC series motor returns to its normal state of driving the electric car with its respective predetermined output.

〔Effect of the invention〕

According to this invention, the decrease in the driving force of the electric motor due to the continuation of the minute idle state that tends to occur in electric cars driven by a DC series motor group using a field control system without being corrected can be avoided. The target value of the armature current is decreased so as to reduce the motor output while this imbalance exists in the field current. If the wheel that had been idling becomes sticky again due to a decrease in motor output, the unbalance of the field current mentioned above will be resolved, so by returning the target value of the armature current to the original value, the wheel idling can be easily stopped. It also has the advantage of being able to reliably eliminate the problem, and that the decrease in motor output during that time is short-lived, and there is no risk of adversely affecting the running schedule of the electric vehicle.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing an embodiment of the present invention, and FIG. 2 is a circuit diagram showing a conventional example of an electric vehicle driven by a group of DC series-wound motors using a field control method. 2-Overhead line, 3-Pantograph, 4 Current setting device, 11
1st armature group, 12 1st field winding group, 13.23
Variable output DC power supply, 14.24 Parallel reactor, 1
5, 25・Armature current detector, 16. 26・−Current regulator, 17, 27 Phase shifter, 21 2nd armature group, 2
2 2nd field winding group, 31. 32 Field current detector, 33 Comparator 16 current adjustment Fig. 1 Fig. Ml Fig.

Claims (1)

[Claims] 1) A field circuit obtained by connecting a reactor in parallel to a circuit in which a variable output DC power supply is connected in series to a plurality of field windings connected in series, and a plurality of armatures each having a wheel connected to the circuit. A DC series motor group is configured by mutually connecting the series-connected armature circuits in series, and the output voltage of the variable output DC power source of each of the plurality of DC series motor groups is adjusted. , in a control method for an electric vehicle driving motor in which the armature current of each motor group is controlled to a predetermined target value, the field current of each DC series motor group is detected separately, and these field currents are A control method for an electric vehicle driving motor, characterized in that when there is a difference between the values, the target value of the armature current is lowered.