JPH01144304A - Controller for electric motor vehicle - Google Patents

Abstract

PURPOSE:To enable control of rotary force of a main motor over a wide speed range, by providing a separately excited winding as well as a series winding to a DC main motor then feeding a portion of current flowing through an exciter side field regulation resistor to the separately excited winding. CONSTITUTION:In an exciter 2, a differential winding 5 to be excited reversely by the load current of a main generator 1 is provided to a shunt generator 4 employing an battery 3 as a power source. Output characteristic of the main generator is regulated to be constant by means of exciting circuit regulating resistors R1-R3 for the exciter 2 and a resistor R4 inserted in series with the exciting coil of the main generator 1. A series motor 6 is connected to the output of the main generator 1. A separately excited winding 11 which is constituted such that it is functionable cumulatively when current (i1) flowing from the battery 3 to the resistor R1 is in same direction as the current flowing through a series winding 7 is connected between the resistor R1 arranged in the exciting winding of the exciter 2 and the exciting battery 3.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) This invention is directed to driving a DC main generator and an exciter by, for example, an internal combustion engine, and transferring the generated power of the DC main motor to the DC main motor. The present invention relates to a control device for an electric vehicle that supplies electricity to drive the vehicle.

(Prior art) For example, in an engine electric vehicle called a diesel electric vehicle, a DC series motor is used as the main motor for driving, and the DC main generator for supplying power to the main motor has a large traction force when starting the vehicle. It is required to supply a low voltage and diode current to the traction motor so that it can output the same amount of power, and to be able to control the voltage to increase and the current to decrease as the vehicle speed increases. Moreover, while the vehicle is running, it is desirable to make maximum use of the engine output over the entire speed range, so it is necessary to have characteristics such that the input per engine is always approximately equal to the maximum engine output, and various Excitation methods have been proposed.

FIG. 5 shows 1%J of a conventional electric vehicle control device used to meet such technical demands, and the main generator 1 driven by the engine (not shown) is , the excitation a2 is excited by the output of the excitation 62 driven by the same engine, and the excitation a2 is a difference in which the shunt generator 4 whose power source is the battery 3 is reversely excited by the load current of the main generator 1. This is a configuration in which a moving winding 5 is provided.

The output characteristics of the main generator 1 are adjusted to a substantially constant output by the excitation circuit adjusting resistors R1 to R3 of the excitation R2 and the resistor R4 directly inserted into the excitation coil of the main generator 1.

FIG. 6 shows the relationship between the currents i1 to i4 flowing through these resistors R1 to R4, the main tR output voltage Vg, and the current Ig. In other words, the exciting current 11 to i3 is generated by the exciter 2.
is controlled, and the main generator 1 is controlled by this excitation current iI to i3.
The excitation current i4 flowing through the excitation coil is determined. The exciting current i4 of the main generator 1 determines the output voltage Vg and output current Ig of the main generator 1.

However, if the series-wound traction motor 6 is simply connected to the output characteristics of the main generator 1, the engine output will only be generated as traction force within a narrow speed range, so generally speaking, the output characteristics of the main generator 1 are as shown in FIG. A weakening resistor 8 is connected in parallel to the series winding 7 of the traction motor 6 via a contactor 9, and after operating at full field (FF) up to a certain speed V, when the speed V is reached, the traction motor 6 The current flowing through the series winding 7 is shunted to a weakening resistor 8 to be used as a field weakening (WF).

By doing this, as shown in FIG. 7, even though the actual current flowing through the series winding 7 is the same as the conventional one, the shunt flowing through the weakening resistor 8 is added, so that the main motor 1
It is possible to increase the control width of the total current flowing through 16,
This allows the engine output to be used effectively as traction over a wider speed range.

(Problems to be Solved by the Invention) However, even with such a conventional electric vehicle control device, there are the following problems.

That is, if such control is to be carried out, as shown in FIG. A voltage detection circuit 10 is required to
There was a problem in that the weight of the controller and the installation space were unavoidable.

Furthermore, as shown in Fig. 7 (a), when the weakening resistor 8 is turned on at the speed V, the current of the main motor!!16 increases, but if we only look at the stable current at the speed V at this time, Although the traction force of the main motor 6 is the same before and after the weak field, the torque of the main motor 6 fluctuates due to very short-term transient phenomena.This situation is shown in FIG.

When the weakening resistor 8 is turned on at time t1 as shown in FIG. 8<a), the main motor current I
g rises in a relatively short time T+ (about several tens of m5ec),
However, as shown in the figure (c), the output voltage Vg of the main generator 1 reversely excites the differential winding 5 of the exciter 2 in response to the change in the main motor current Ig, and the Output voltage decreases.

Due to this decrease in output voltage, the current I4 to the machine field winding decreases, and the output voltage Vg also decreases.There are multiple electrical delay factors, so it takes a considerable amount of time to stabilize the output voltage. Time T2 (several hundred m5ec to 1sec)
Therefore, until the voltage stabilizes at a low value, the traction motor torque remains at T3 for a short time as shown in (d) of the same figure.
This results in an increase in For this reason, there was a problem in that torque shock and vibration occurred during operation, which worsened the riding comfort when towing a passenger car, and caused the wheels to slip and cause flatness (partial wheel wear).

This invention was made to solve these conventional problems, and it does not require field-weakening switching resistors, contactors, voltage detection circuits, etc., and can provide stable traction force over a wide speed range. The purpose of this invention is to provide a control device for electric vehicles that can be used for electric vehicles.

[Structure of the Invention] (Means for Solving the Problems) This invention has a single DC TLL and an exciter, and adjusts the resistance inserted into the excitation circuit between the main generator and the exciter. In an electric vehicle control device that controls the rotational force of the main motor according to the output characteristics determined by the main 1! A separately excited winding is provided so that it acts harmoniously when current flows in the same direction as the series winding of the motor, and this separately excited winding is connected to the field winding of the exciter. It is connected to a line that flows from the line excitation battery to the exciter field adjustment resistor, and the exciter current is made to flow through the other excitation windings.

1: In the control device for an electric vehicle of this invention, the DC main motor is provided with a passive winding in addition to the series winding, and in addition to this, the excitation winding is configured to control the current flowing through the field adjustment resistor on the exciter side. By partially energizing, the series winding of the traction motor and the magnetomotive force act in harmony when the vehicle starts, and when the vehicle starts traveling at high speed, the magnetomotive force acts to cancel each other out, resulting in the rotational force of the traction motor. can be controlled over a wide speed range.

(Example) Hereinafter, embodiments of the present invention will be explained in detail based on the drawings.

FIG. 1 shows an embodiment of the present invention, in which a main generator 1, an exciter 2, a battery 3, a shunt generator 4, a differential winding 5, a main motor 6, and a series winding 7 are the same as those of the conventional example. The configuration is similar to that shown in FIG. 5. In addition, resistors R1 to R for adjusting the field of the excitation 812
3. The resistance R4 to the excitation winding of the main generator 1 is also the same as in the conventional example, and therefore operates in the same manner as in the conventional example.

The feature of this embodiment is that the passive winding 11 is connected between the resistor R1 provided in the excitation winding of the excitation 812 and the excitation battery 3, and the passive winding 11 is connected to the main motor R6. This is due to the fact that it is located close to the series winding 7.

This separately excited winding 11 is connected to a resistor R from the battery 3.

When the current 11 flowing through the series winding 7 is in the same direction as the current flowing through the series winding 7, the current 11 acts harmoniously.

The operation of the electric vehicle control device configured as described above will be described next.

The main generator 1 is driven by an engine (not shown), is excited by an excitation current of an exciter 2 which is also driven by the engine, and provides an output of voltage Vg and current 1g to the main motor 6.

The excitation current flowing through the excitation coil of the main generator 1 is controlled so that the output is constant by the current of the exciter 2, which is controlled by the excitation current flowing from the battery 3 via the resistors R1 to R3.

The output characteristics of this main generator 1, from the battery 3 to the separately excited winding 1
Figure 2 shows the characteristics of the current flowing through the main generator 1 and the characteristics of the traction motor field magnetic flux. The inflow current 11 to the exciter excitation circuit also increases to the + side, and the separately excited winding 11 can be excited in the direction in which it works in harmony with the series winding 7, giving a large magnetomotive force to the main motor 6. It is possible to obtain a large traction force.

When the vehicle speeds up, the output voltage V of the main generator 1
g becomes higher and the current 1g becomes lower, but in this case, the current 11 flowing from the battery 3 to the resistor R1 is on one side,
Therefore, a magnetomotive force is generated in the separately excited winding 11 in the opposite direction to that of the series winding 7, weakening the magnetomotive force on the main motor 6 and enabling high-speed rotation.

To explain this characteristic in more detail, let us assume that the state in which current flows only through the series winding 7 is 100% field rate.
The magnetomotive force caused by this is assumed to be As. Further, it is assumed that the magnetomotive force Ah generated by the separately excited winding 11 is used. At this time, the field rate FSs at startup becomes 100% or more, the amount of magnetic flux increases compared to when only the series winding 7 is energized, and low speed and large torque are generated.

Further, the magnetic field factor FSh during high-speed running is as follows, which is smaller than 100%, which is the same as when an equivalent weakening resistor is inserted, and the amount of magnetic flux becomes small, resulting in high-speed rotation.

This change in field rate is shown in FIG. 2(c).

Changes in the current Ig of the main electric motor 816, field rate, and traction force with respect to the vehicle speed when performing separately excited field control in this way are shown in FIG. 3(a), and the output characteristics of the main generator 1 are shown in FIG. b).

A large traction force is required when starting the vehicle, and by increasing the current 1 g and adding the magnetomotive force by the separately excited winding 11, the field rate can be increased and a large maneuverability can be obtained.

When running at high speed, the current Ig is lowered and the voltage Vg is increased, and the passive winding 11 causes the main motor 6 to
The rotational speed can be increased by suppressing the magnetomotive force and lowering the magnetic field rate.

FIG. 4 shows another embodiment of the present invention. In the first embodiment, the excitation circuit adjustment resistor R1 of the exciter 2 is connected to the battery 3.
The current i1 flowing through the main motor R6 is directly connected to the passive winding 11 of the main motor R6.
In order to adjust the number of turns of the separately excited winding 11, field weakening rate, etc., a shunt resistor R is installed before the adjustment resistor R1.
5 is inserted so that a shunt current 11- flows through the separately excited winding 11.

With this configuration, by adjusting the shunt resistor R5, the shunt current 1. - can be adjusted, making it possible to finely adjust the control characteristics.

[Effects of the Invention] As described above, the present invention has a DC main generator and an exciter, and the output characteristics are determined by adjusting the adjustment resistors inserted in the excitation circuits of the main generator and the exciter. In a control device for an electric vehicle that supplies power to a traction motor, a passive winding is provided that works in harmony with the series winding of the traction motor,
In addition, the current flowing from the battery for excitation of the exciter winding to the excitation circuit adjustment resistor is passed through the excitation winding, so when the vehicle is started, the current generated by the series winding due to the load current of the main generator is generated. Strong starting torque can be given to the traction motor by the magnetomotive force of the passive winding due to the main generator excitation current in addition to the magnetomotive force, and when the traction motor rotates at high speed, the magnetomotive force due to the series winding of the traction motor is This is canceled out by the magnetomotive force in the opposite direction due to the excitation wire, and by lowering the field rate, high-speed rotation is possible, and control can be performed over a wide speed range.

Moreover, according to the present invention, there is no need for a weakening resistor, a contactor for making it, a voltage detection circuit, etc., as in the past.
It is possible to avoid increasing the size of the device. Furthermore, since there is no component such as a dosing device that intermittents the current, torque shock does not occur and smooth control is possible.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of an embodiment of the present invention, and FIG. 2 is an operating characteristic diagram of the above embodiment, where (a) is an output characteristic graph of the main generator, and (b) is a graph of the battery. FIG. 3(c) is a characteristic graph of the current flowing into the exciter circuit of the exciter, FIG. 3(c) is a graph of the field rate characteristic of the traction motor, and FIG. The graph shown in FIG. 3(b) is a graph explaining the operating characteristics of the above embodiment.
Figure 4 is a circuit diagram of another embodiment of the present invention, Figure 5 is a circuit diagram of a conventional example, Figure 6 is a graph showing the operating characteristics of a conventional main generator, Figures 7 and 8. - is an explanatory diagram of the operation of a conventional electric vehicle. 1... Main generator "X machine" 2... Exciter machine 3...
Battery 4... Shunt motor 5... Differential winding 6... Main motor 7... Series winding
11...Passive winding 11-I4...Exciting current Ig
... Output current R1 to R4 ... Excitation circuit adjustment resistor

Claims (1)

[Claims] The main motor has a DC main generator and an exciter, and the rotational force of the main motor is controlled according to the output characteristics determined by adjusting the resistance inserted in the excitation circuit of the main generator and the exciter. In a control device for an electric vehicle, a separately excited winding is provided to act harmoniously when current flows in the same direction as the series winding of the main motor.
The other excitation winding is connected to a line flowing from the field winding excitation battery of the exciter to the exciter field adjustment resistor, and the exciter current is caused to flow through the other excitation winding. car control device.