JP2012105452A - Electric vehicle control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide speed detection control and electric vehicle control with high accuracy by together using a speed estimation detection part of sensorless vector control in an electric vehicle control device where a speed pulse generator is attached to an axle.SOLUTION: The electric vehicle control device comprises: a pulse speed conversion part 10 which converts a pulse signal from a speed pulse generator 9 into an angular speed and provides it as detection angular speed; a vector control part 3 which performs vector control of a main electric motor 6; and a speed correction part 11a which estimates an angular speed of the main electric motor 6 from an electric current detection value and an electric voltage instruction of an inverter 5, corrects an estimation angular speed using the detection angular speed obtained from the pulse speed conversion part, and provides it to the vector control part 3 as speed information. When the difference between the estimation angular speed and the detection angular speed from the pulse speed conversion part 10 is a predetermined value or more, the speed correction part 11a provides the detection angular speed to the vector control part 3 as the speed information, and when the difference between the estimation angular speed and the detection angular speed from the pulse speed conversion part 10 is less than the predetermined value, the speed correction part 11a provides the estimation angular speed to the vector control part 3 as the speed information.

Description

  The present invention relates to a control device for an electric vehicle in which a speed detection pulse generator is mounted not on an induction motor shaft but on a wheel axle.

  When the induction motor is large and the rotation speed detection pulse generator cannot be attached to the motor shaft due to restrictions on dimensions such as the track width, there is a method of attaching the pulse generator to the wheel axle. FIG. 3 shows a conventional configuration example of an electric vehicle control apparatus to which such a method is applied.

  The electric vehicle control apparatus 101 includes a vector control unit 102, an inverter unit 103, an induction motor 104, a pulse generator 107, a pulse / speed conversion unit 108, and an idling sliding control unit 107.

  The vector control unit 102 executes a vector control of the electric motor 104 by inputting a torque command value corresponding to a notch command provided from a master controller of the cab. The inverter unit 103 is driven by a PWM signal generated based on the voltage command generated by the vector control 102. The rotation of the induction motor 104 is controlled by the AC voltage output from the inverter unit 108. The pulse generator 107 is attached to the axle of the wheel 106 connected to the induction motor via the gear 105, and generates a pulse for speed detection. The pulse / velocity conversion unit 108 converts the pulse from the pulse generator 107 into an angular velocity. The idling / sliding control unit 107 detects idling or sliding of the wheel and reduces the magnitude of the torque command.

  As shown in FIG. 3, in the method of detecting the speed by a pulse generator attached to the wheel axle, the axle is driven by an induction motor through the gear 105, and therefore the speed is detected by gear backlash or shaft torsion. There is a problem that ripple (detection error) is added to the pulse signal for detection, and this ripple becomes noise and speed detection accuracy is deteriorated.

  In order to remove the ripples superimposed on the speed detection signal of the pulse generator 107, a noise removing filter or the like is required separately, which not only complicates the apparatus configuration but also delays control. There was a problem that quick vector control became impossible.

  Some conventional electric vehicle control devices perform sensorless control when the induction motor is large and a pulse generator is not attached to the induction motor shaft. In this case, the idling control must be performed based on the estimated speed, and the idling speed detection is delayed and the accuracy is poor.

  The present invention has been made in view of the above circumstances, and in an electric vehicle control device in which a pulse generator is attached to an axle, the speed estimation unit of sensorless vector control is used together, so that accurate speed detection control and electric vehicle control can be performed. The purpose is to provide.

  In order to achieve the above object, according to an embodiment of the present invention, in an electric vehicle control apparatus that controls a main motor by an inverter, a pulse generator that generates a pulse signal corresponding to the rotation speed of an axle, and the pulse generator The voltage to the inverter is converted based on the pulse speed conversion unit that converts the pulse signal of the motor to the angular speed and provides it as the detected angular speed, the input torque command, the output current detection value of the inverter, and the speed information of the motor. A vector control unit that calculates a command and vector-controls the electric motor, estimates an angular velocity of the electric motor from the voltage command and the current detection value, and calculates the estimated angular velocity by a detected angular velocity obtained from the pulse velocity conversion unit. A speed correction unit that corrects and provides the vector information to the vector control unit as the speed information. If the difference between the detected angular speed from the speed conversion unit and the estimated angular velocity is a predetermined value or more, to provide the angular velocity detected as the velocity information, otherwise, to provide said estimated angular velocity.

It is a block diagram which shows 1st Embodiment of the electric vehicle control apparatus which concerns on this invention. It is a block diagram which shows 2nd Embodiment of the electric vehicle control apparatus which concerns on this invention. It is a block diagram which shows an example of the conventional electric vehicle control apparatus.

  Embodiments of an electric vehicle control device according to the present invention will be described below with reference to the drawings.

  FIG. 1 is a block diagram showing a configuration of a first embodiment of an electric vehicle control device according to the present invention.

  The electric vehicle control device 1 a includes a vector control unit 3, an inverter unit 5 that drives the induction motor 6 according to a three-phase voltage command from the vector control unit 3, and an axle of a wheel 8 that is connected to the induction motor 6 via a gear 7. A pulse generator 9 that outputs a pulse signal corresponding to the number of revolutions of the motor, a pulse / speed converter 10 that converts the pulse signal into a speed signal, and a three-phase output current supplied from the inverter 5 to the induction motor 6 are detected. And a current sensor 12 that outputs to the vector control unit 3.

  The vector control unit 3 internally generates a d-axis and q-axis (hereinafter referred to as dq-axis) current command of the rotor from a torque command value input from the mass control 2 provided on the cab or the like, and the d-axis current PI control (proportional / integral control) is executed using the command and feedback d-axis current detection value Id, and the q-axis current command and feedback q-axis current detection value Iq, and d-axis voltage commands Vd and q A shaft voltage command Vq is generated. Further, the vector control unit 3 generates the d-axis position signal θ of the rotor based on the dq-axis current command and the speed signal ω2 from the speed correction unit.

  The pulse / speed converter 10 converts the pulse signal from the pulse generator 9 provided on the axle into a speed signal (rotational angular speed) ω1. The speed correction unit 11 generates a corrected speed signal ω2, which will be described later, based on the dq axis voltage commands Vd, Vq, the dq axis current detection values Id, Iq, and the speed signal ω1 from the pulse / speed conversion unit 10.

  The coordinate conversion unit 4 converts the dq axis voltage commands Vd and Vq into three-phase AC voltage commands Vu, Vv, and Vw based on the position signal θ and supplies them to the inverter unit 5. The coordinate conversion unit 13 converts the three-phase output current detection values Iu and Iw detected by the current sensor 12 into dq-axis currents Id and Iq based on the position signal θ.

  In the first embodiment, the pulse signal output from the pulse generator 9 attached to the axle of the wheel 8 is converted into the angular velocity ω 1 by the pulse / speed conversion unit 10 and supplied to the speed correction unit 11. The speed correction unit 11 corrects the estimated angular speed value ωh with reference to the speed signal ω1, and provides a corrected speed signal ω2.

  Hereinafter, the speed correction unit 11 will be described in detail.

  The speed correction unit 11 calculates the estimated angular speed ωh of the electric motor 6 based on, for example, the dq axis voltage commands Vd and Vq and the dq axis current detection values Id and Iq. This estimated angular velocity ωh is generally more accurate (close to the actual value) than the detected angular velocity ω1 obtained from the pulse / velocity conversion unit 10 in normal operation without disturbance. However, when idling or gliding occurs, the estimation calculation cannot keep up with the speed change, resulting in a calculation error. Therefore, when idling or sliding occurs, the detected angular velocity ω1 is more accurate than the estimated angular velocity ωh.

  The comparison unit 15 compares the estimated angular velocity ωh with the detected angular velocity ω1 from the pulse / velocity conversion unit 10, and when the absolute value of the differential velocity (= ωh−ω1) is greater than a predetermined value A, idling or sliding occurs. The detected angular velocity ω1 is output as the corrected angular velocity ω2. When the differential speed is less than or equal to a predetermined value, that is, during normal running, the speed correction unit 11 outputs the estimated angular speed ωh as the corrected angular speed ω2.

  As a result, since the vector control unit 3 always uses the higher angular velocity, that is, the corrected angular velocity ω2, the accuracy of vector control of the electric motor is improved. It should be noted that the predetermined value A, which is a judgment criterion for idling / sliding, may be set to a different value between idling and sliding according to the characteristics of the electric vehicle control device.

  Next, a second embodiment of the present invention will be described.

  FIG. 2 is a block diagram showing the configuration of the second embodiment of the electric vehicle control device according to the present invention. The same components as those in the first embodiment of FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted.

  The electric vehicle control device 1b according to the second embodiment includes an idle running control unit 14 and a speed estimation unit 11b instead of the speed correction unit 11a as compared with the electric vehicle control device 1a according to the first example. . A feature of the electric vehicle control device 1b in the second embodiment is that the idling / sliding of the axle is determined based on only the speed signal converted by the pulse / speed converter 10, and the torque command is corrected.

  Similar to the speed correction unit 11a, the speed estimation unit 11b calculates the estimated angular speed ωh of the electric motor 6 based on, for example, the dq axis voltage commands Vd and Vq and the dq axis current detection values Id and Iq. However, unlike the speed correction unit 11a, the speed estimation unit 11b does not perform speed correction. The idling / sliding control unit 14 determines the idling / sliding situation between the wheels and the rails based on the speed signal converted by the pulse / speed converting unit 10. The idling / sliding control unit 14 includes a differential calculation unit 16, which differentiates the detected angular velocity ω <b> 1 provided from the pulse / speed conversion unit 10 to obtain an acceleration / deceleration. When the absolute value of the acceleration / deceleration exceeds a predetermined value B, the idling / sliding control unit 14 outputs the excess. During deceleration, a minus sign is added to the excess, and a plus is added during acceleration.

  The subtracter 17 subtracts the excess supplied from the idling / sliding control unit 14 from the torque command from the mascon. The torque command value provided from the mascon 2 is a positive value if it is an acceleration command, and a negative value if it is a deceleration command. That is, the torque command value from the master controller 2 is weakened by this excess. As a result, the idling or sliding state is avoided. It should be noted that the predetermined value B, which is a judgment criterion for idling / sliding, may be set to a different value between idling and sliding according to the characteristics of the electric vehicle control device.

  As described above, in this embodiment, by performing the idling / sliding control using only the speed signal from the pulse / velocity conversion unit 10, it is possible to perform the idling / sliding control with high accuracy, and insufficient acceleration due to idling or braking due to the sliding. An increase in distance can be prevented.

  The above-described embodiment of the present invention is particularly preferably applied to a locomotive of a freight train that easily causes slipping and sliding. Moreover, the above-described embodiments can be applied not only to induction motors but also to synchronous motors.

  The above description is an embodiment of the present invention, and does not limit the apparatus and method of the present invention, and various modifications can be easily implemented. For example, various inventions can be configured by appropriately combining a plurality of constituent elements disclosed in the embodiment.

  DESCRIPTION OF SYMBOLS 1a, 1b ... Electric vehicle control apparatus, 2 ... Masscon, 3 ... Vector control part, 4 ... Coordinate conversion part, 5 ... Inverter part, 6 ... Induction motor, 7 ... Gear, 8 ... Wheel, 9 ... Pulse generator, 10 ... Pulse / velocity conversion, 11 ... speed correction unit, 12 ... current sensor, 13 ... coordinate conversion unit, 14 ... idling and sliding control unit.

Claims (6)

In an electric vehicle control device for controlling a main motor by an inverter,
A pulse generator that generates a pulse signal corresponding to the rotational speed of the axle;
A pulse speed converter that converts the pulse signal from the pulse generator into an angular velocity and provides it as a detected angular velocity;
Based on the input torque command, the output current detection value of the inverter, and the speed information of the electric motor, a voltage command to the inverter is calculated, and a vector control unit that vector-controls the electric motor,
The angular velocity of the electric motor is estimated from the voltage command and the detected current value, the estimated angular velocity is corrected using the detected angular velocity obtained from the pulse velocity conversion unit, and the velocity provided to the vector control unit as the velocity information A correction unit,
The speed correction unit provides the detected angular speed as the speed information when a difference between the detected angular speed and the estimated angular speed from the pulse speed conversion unit is a predetermined value or more, and otherwise, the estimated angular speed is An electric vehicle control device characterized by being provided.   The electric vehicle control device according to claim 1, wherein the main motor is an induction motor. In an electric vehicle control device for controlling a main motor by an inverter,
A pulse generator that generates a pulse signal corresponding to the rotational speed of the axle;
A pulse speed converter that converts the pulse signal from the pulse generator into an angular velocity and provides it as a detected angular velocity;
Based on the input torque command, the output current detection value of the inverter, and the speed information of the electric motor, a voltage command to the inverter is calculated, and a vector control unit that vector-controls the electric motor,
A speed estimation unit that estimates an angular velocity of the electric motor from the voltage command and the current detection value, and provides the estimated angular velocity to the vector control unit as the speed information;
Differentiating the detected angular velocity from the pulse velocity conversion unit, if the absolute value of the differential value is greater than a predetermined value, it is determined that idling or sliding has occurred, and the absolute value of the torque command is reduced according to the differential value An idling control unit that corrects the value,
An electric vehicle control device comprising:   4. The electric vehicle control device according to claim 3, wherein the main motor is an induction motor. In a method for controlling an electric vehicle in which a main motor is controlled by an inverter,
Convert the pulse signal corresponding to the rotation speed of the axle to the angular velocity and provide it as the detected angular velocity,
Based on the input torque command, the output current detection value of the inverter, and the speed information of the electric motor, the voltage command to the inverter is calculated, and the electric motor is vector-controlled,
Estimating the angular velocity of the electric motor from the voltage command and the detected current value, correcting the estimated angular velocity with the detected angular velocity, and providing the vector control as the velocity information,
The correction of the estimated angular velocity provides the detected angular velocity as the velocity information when a difference between the detected angular velocity and the estimated angular velocity is a predetermined value or more, and otherwise provides the estimated angular velocity. Electric vehicle control method. In a method for controlling an electric vehicle in which a main motor is controlled by an inverter,
Convert the pulse signal corresponding to the rotation speed of the axle to the angular velocity and provide it as the detected angular velocity,
Based on the input torque command, the output current detection value of the inverter, and the speed information of the electric motor, the voltage command to the inverter is calculated, and the electric motor is vector-controlled,
Estimating the angular velocity of the motor from the voltage command and the current detection value, providing the estimated angular velocity as the velocity information to the vector control,
Including differentiating the detected angular velocity, determining that idling or sliding has occurred when the absolute value of the differential value is greater than a predetermined value, and correcting the absolute value of the torque command to a smaller value according to the differential value. An electric vehicle control method.

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