JP2000092629A - Controller for electric motor car - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable torque control by inputting the motor car speed information corresponding to a motor car speed of one of a train monitor, an automatic train controller, a motor car speed detector, etc., to a change-over device, and performing changeover at the start of an inverter. SOLUTION: A primary interlinkage flux vector is computed for compensating voltage information v by an amount corresponding to a voltage drop caused by the resistance of a primary coil, and a real torque is obtained by the vector product of a primary interlinkage flux and a primary current. Along with obtaining a secondary interlinkage flux from the primary interlinkage flux and the primary current, a secondary angular frequency ω2 is found, and a slippage angular frequency ωs is obtained from the values of the secondary interlinakge flux, the real torque, and the resistance of a secondary coil. Although a change-over device 17 selects a signal ωm which is the output of the motor speed information 18 of a train monitor, etc., in place of a signal ωm' which is the output of a torque control unit 16 in a specified period after starting, the change-over device 17 performs changeover so as to select the computed value ωm' of the angular frequency of a rotor by detecting that the error between ωm and ωm' became equal to or lower than a value set beforehand. Consequently, it becomes possible to perform torque control at the start time as well.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric vehicle control device for controlling the torque of an induction motor for propulsion and electric braking in a railway vehicle, and more particularly to an inverter device.

[0002]

2. Description of the Related Art Conventionally, an inverter device for controlling the torque of an induction motor for propulsion and electric braking in a railway vehicle or the like has already been put into practical use with a basic configuration as shown in a block diagram of FIG. For example, the torque control of the vehicle is performed such that a current command value proportional to the torque is given a positive polarity during acceleration, and the command value is given a negative polarity during electric braking. Is converted to an effective value or the like) so that the slip frequency command ωs
To configure an automatic control system that varies Slip frequency command ω
s is added to a signal (converted to a rotor frequency) from a speed sensor connected to the shaft of the motor to determine the output frequency of the inverter, that is, the primary frequency ωe of the motor. The output voltage of the inverter has a substantially constant voltage-frequency relationship in a relatively low frequency range, and remains at the constant voltage in a frequency range higher than the frequency at which the inverter's output voltage is the upper limit. The above is the basic form of the torque control of the conventional vehicle inverter device.

[0003] In FIG. 2, an inverter control unit 12 comprises:
In response to the frequency command ωe output from the torque control unit 16 ′, PWM control that satisfies the voltage-frequency relationship is performed, and the DC voltage taken from the current collector 11 is converted into an AC voltage and a desired frequency. Although only one induction motor 15 is shown in the figure, two or four induction motors may be connected in parallel in a conventional device. In the conventional torque control method, the speed sensor 13 is an essential component of the electric vehicle control device. In recent years, the torque control uses the instantaneous value of three-phase alternating current without using the effective current value to calculate the primary interlinkage flux vector, the secondary interlinkage flux vector, and the output torque of the motor by arithmetic processing. As a result, the secondary angular frequency and the slip angular frequency are obtained, and finally the rotor angular frequency can be obtained. As a result, torque control can be realized without providing a speed sensor connected to the rotating shaft of the electric motor.

[0004]

An operation method peculiar to an inverter device for a vehicle includes repetition of powering (acceleration) and regenerative (or deceleration of braking) operations, and an inverter called coasting between respective operation states. Stop and run without applying voltage to the motor. If no speed sensor is provided, the inverter device cannot obtain the rotation speed information of the electric motor during this coasting. When starting re-powering or regenerative deceleration operation from this state, there is a state where the above-described primary / secondary interlinkage magnetic flux vector calculation value is not accurately obtained,
As a result, there is a possibility that the rotor angular frequency is not determined to a predetermined value and predetermined acceleration / deceleration cannot be performed. This is because the magnitude of the magnetic flux vector obtained from the current flowing at the time of starting is too small, or a magnetic flux having a predetermined magnitude with respect to the current value cannot be obtained. The present invention has been made in view of the above points, and an object of the present invention is to provide an electric vehicle control device that solves these disadvantages.

[0005]

Means for achieving the object are as follows: (1) In the first aspect, there are provided a current detecting means and a voltage detecting means for the inverter output, and the respective detected values and motor constants are provided. Is used to estimate the primary flux linkage vector, the secondary flux linkage vector, and the output torque, and from these values, the rotational speed of the motor rotor is estimated.This rotational speed is proportional to the rotor angular frequency. An electric vehicle control device having an inverter control unit that adds a slip frequency equivalent to the rotor angular frequency and sets an output frequency of the inverter, wherein a switch that switches output of the rotor angular frequency signal is provided, and an inverter device and Vehicle speed information corresponding to any vehicle speed, such as a train monitor device, an automatic train control device (ATS, ATC), a vehicle speed detection device, etc., operating independently. When the inverter starts, it switches to the external vehicle speed information, and when the value of the vector calculation falls within a predetermined error range with respect to the external vehicle speed information, its own speed is changed. An electric vehicle control device characterized by switching to a detection signal.

(2) In claim 2, a switch for switching the output of the rotor angular frequency signal is provided, and the train monitor, the automatic train control (ATS, ATC), and the vehicle operate independently of the inverter. Vehicle speed information corresponding to one of the vehicle speeds such as a speed detection device is input to the switch, and when the inverter is started, the speed is switched to the external vehicle speed information, and the magnitude of the magnetic flux of the vector calculation becomes smaller than a predetermined value. 2. The electric vehicle control device according to claim 1, wherein the electric vehicle control device switches to an own speed detection signal when the speed becomes large. Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram showing an embodiment of the present invention according to claim 1 of the present invention.
Only 8) will be described. In FIG. 1, a current collector 11, an inverter control unit 12, a current detector 14, and a motor 15 are the same as those in FIG. 3, and the torque control unit 16 of the present invention requires a speed sensor to be connected to the rotating shaft of the motor. If not. The current i is taken from the current detector 14, but the voltage information v
Is input from the inverter control unit 12 as a DC input voltage and a waveform signal 19 to which PWM control is added. This voltage information v is used to calculate the primary linkage flux vector by correcting the voltage drop due to the primary winding resistance. The actual torque is obtained by the vector cross product of the primary linkage flux and the primary current. Considering the component in the secondary current direction included in the primary interlinkage magnetic flux, the secondary interlinkage magnetic flux is obtained from the primary interlinkage magnetic flux and the primary current, and the secondary angular frequency ω2 is further obtained. The slip angular frequency ωs is obtained from the value of the secondary interlinkage magnetic flux, the actual torque, and the secondary winding resistance, and the rotor angular frequency ωm is expressed by the following equation.

Ωm = ω2−ωs The rotor angular frequency ωm obtained from the output information of the inverter is
The slip angle frequency command ωs * obtained from the torque command is added by the adder 20 to obtain an inverter frequency command ωe ′.

The switch 17 receives the signal ωm ′, which is the output of the torque control unit 16, separately from the inverter control unit during a predetermined period after the inverter control unit is stopped (during stop and coasting), for example, The signal ωm which is the output of the vehicle speed information 18 of the train monitor is selected. In the case of a train monitor, a serial data transmission line is often provided, and the number of outfitting lines is rarely increased. The automatic train control device (AT
S, ATC), when a speed signal is taken in parallel, even if the speed sensor is the same, taking a signal from an independent output terminal in terms of an electric circuit, a fault on the inverter device side does not spread to a fault on the external device. To consider. There is also a method in which one or two sensors that detect the vehicle speed by optical or ultrasonic or radio wave measurement are provided for each train without providing a sensor in the rotating part such as wheels, etc. The present invention is also effective in a system in which the speed is taken into the inverter device from an external device. It is assumed that the switch 17 in FIG. 1 includes a part for detecting an error between the signals ωm and ωm ′ in this block. The switch that selected ωm at the time of starting
Upon detecting that the error of m 'has become equal to or less than a preset value, the switching is performed so as to select the calculated value ωm' of the rotor angular frequency. This state is maintained during the operation of the inverter control unit.

FIG. 2 is a block diagram showing one embodiment of the second aspect of the present invention, in which the switching conditions of the signals ωm and ωm ′ are different. As described above, the undetectable state of ωm ′ occurs when the magnetic flux is small. Therefore, for example, the magnetic flux level detecting unit 2 for detecting that the magnitude of the secondary linkage magnetic flux has become larger than a predetermined value.
1, and the switch 17 is switched from ωm to ωm ′ by this output. Since the use of an external speed signal tends to cause a torque control error, it is more convenient to switch to the speed signal detected by itself as soon as possible in terms of control characteristics.

[0011]

As described above, according to the present invention, the torque control of the induction motor can be performed even at the time of starting by the torque control device for the induction motor by the inverter, which is extremely useful in practical use.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the first aspect of the present invention.

FIG. 2 is a block diagram showing one embodiment of the second aspect of the present invention.

FIG. 3 is a block diagram illustrating an example of the related art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Current collector 12 Inverter control part 13 Speed sensor 14 Current detector 15 Induction motor 16 Torque control part 17 Switching device 18 Vehicle speed information 19 Waveform signal 20 Adder 21 Magnetic flux level detection part

 ──────────────────────────────────────────────────続 き Continuing on the front page F term (reference) 5H115 PC02 PG01 PI03 PI29 PU09 PV09 QE01 QE20 QN09 QN27 RB24 SL01 SL05 TB01 TB06 TO04 TO11 TO12 TO13 TO16 TO30 5H576 AA01 BB10 CC01 DD02 DD04 EE03 EE11 FF01 GG04 LL10 LL24 LL34 LL38 LL60

Claims (2)

[Claims] The present invention has a current detecting means and a voltage detecting means for an inverter output, and estimates a primary interlinkage magnetic flux vector, a secondary interlinkage magnetic flux vector and an output torque using respective detected values and a motor constant. Estimate the rotation speed of the motor rotor from the value, this rotation speed is proportional to the rotor angular frequency, and has an inverter control unit that adds the slip frequency equivalent to this rotor angular frequency and sets the output frequency of the inverter In the electric vehicle control device, a switch for switching the output of the rotor angular frequency signal is provided, and a train monitor device, an automatic train control device (ATS, ATC), a vehicle speed detection device, and the like that operate independently of the inverter device. The vehicle speed information corresponding to any one of the vehicle speeds is input to the switch, and when the inverter is started, the speed is switched to the external vehicle speed information. When the value of the vector operation has entered the predetermined error range with respect to the outside of the vehicle speed information, the electric vehicle control apparatus and switches its own speed detection signal. 2. A train monitor, an automatic train controller (ATS, AT) which is provided with a switch for switching the output of a rotor angular frequency signal and which operates independently of an inverter.
C), vehicle speed information corresponding to one of the vehicle speeds such as a vehicle speed detection device is input to the switch, and when the inverter is started, the speed is switched to the external vehicle speed information. 2. The electric vehicle control device according to claim 1, wherein the control is switched to the own speed detection signal when the speed becomes larger than a predetermined value.