JP5816812B2 - Motor drive device - Google Patents

Description

  The present invention relates to a motor drive device that controls a motor position to follow a command position and has a gain switching function.

  In the servo motor positioning control, the motor position is controlled to follow the position command output from the host controller. In that case, the required performance includes shortening of settling time and reduction of vibration.

  Various control gains will be adjusted to meet the required performance, but a method has been proposed that shortens the settling time and reduces vibrations by switching the control gain according to the operating conditions of the motor. (For example, refer to Patent Document 1).

  In this method, the motor operating state is classified into an acceleration / deceleration state, a constant speed state, and a stop state, and a control gain corresponding to the state is applied. The required specifications such as reduction of chute and stability at a constant speed state can be handled with different control gains.

JP 2000-293234 A

  However, although the above-described technique is effective for a specific position command pattern, the specification of the device and the required specification cannot be consistent with different specifications such as when the shape of the position command changes. Cases are also considered. For example, even when the acceleration / deceleration is the same, when the position command distance is short, the shape of the position command speed is a triangular wave, and when the position command distance is long, the shape is a trapezoidal wave. Even if the control gain is optimized with respect to the trapezoidal wave by the above-described technique, vibration or the like again occurs when the command changes to a triangular wave. In other words, there is a case where further higher performance is required because it is not a technology that supports the optimization of the control gain for different position command distances.

  The present invention solves the above-described conventional problems, and a motor drive device capable of individually optimizing the control gain with respect to the case where the position command distance is different, in order to meet the demand for higher performance. The purpose is to provide.

  In a first aspect of the present invention, in the motor control apparatus that controls the motor position to follow the position command, the position control output is calculated so that the position deviation is converged to 0 using the position control gain selected by the gain switching signal. Position control means, speed control means for calculating the speed control output so that the speed deviation is converged to 0 using the speed control gain selected by the gain switching signal, and current control output for driving the motor according to the torque command Current control means for calculating the speed, speed feed forward means for calculating the speed feed forward output from the position command using the speed feed forward gain selected by the gain switching signal, and the torque feed selected by the gain switching signal. Calculate torque feed forward output from speed feed forward output using forward gain Torque feed-forward means, speed detection means for calculating motor speed from motor position, position command speed detection means for calculating position command speed from position command, gain command signal from position command speed, judgment delay time and judgment threshold Gain switching determination means for turning ON / OFF, determination delay time setting means for setting a determination delay time, and determination threshold setting means for setting a determination threshold, and after the determination delay time has passed by the gain switching determination means If the absolute value of the position command speed is equal to or smaller than the determination threshold, the gain switching signal is turned on. If the absolute value of the position command speed is larger than the determination threshold, the motor driving device is configured to keep the gain switching signal off.

  According to a second aspect of the present invention, in the motor control device that controls the motor position to follow the position command, the position control output is calculated so that the position deviation is converged to 0 using the position control gain selected by the gain switching signal. Position control means, speed control means for calculating the speed control output so that the speed deviation is converged to 0 using the speed control gain selected by the gain switching signal, and current control output for driving the motor according to the torque command Current control means for calculating the speed, speed feed forward means for calculating the speed feed forward output from the position command using the speed feed forward gain selected by the gain switching signal, and the torque feed selected by the gain switching signal. Calculate torque feed forward output from speed feed forward output using forward gain Torque feed-forward means, speed detection means for calculating motor speed from motor position, position command speed detection means for calculating position command speed from position command, gain command signal from position command speed, judgment delay time and judgment threshold Gain switching determination means for turning on / off, determination delay time setting means for setting a determination delay time, determination threshold setting means for setting a determination threshold, and gain switching duration setting means for setting a gain switching duration If the absolute value of the position command speed after the judgment delay time has passed is less than or equal to the judgment threshold value, the gain switching signal is turned on for the gain switching duration, and if it is larger than the judgment threshold value, the gain switching signal is turned off. It is a motor drive device which comprises the composition which remains.

  According to the motor drive device of the present invention, the optimum control gain can be applied to each of two states having different position command distances.

1 is a block diagram of a motor drive device according to a first embodiment of the present invention. FIG. 3 is a timing chart of the motor driving device according to the first embodiment of the present invention. The block diagram of the motor drive device in Example 2 of this invention. Timing diagram of motor drive device in Embodiment 2 of the present invention

  Hereinafter, the present invention will be described with reference to the drawings. In addition, this invention is not limited by the following examples.

  FIG. 1 is a block diagram of the motor driving apparatus according to the first invention. In FIG. 1, the position control means 1 outputs a position control output 22 from a position deviation 21 which is a difference between the position command 20 and the motor position 29 and a gain switching signal 34, and the speed control means 2 is a position control output 22 and a speed. The speed control output 24 is output from the speed deviation 23 which is the difference between the added value of the feedforward output 27 and the motor speed 30, and the gain switching signal 34. The current control means 3 outputs the speed control output 24 and the torque feedforward output 28. The current control output 26 is output from the torque command 25 that is an addition value of the following, the speed feedforward means 4 outputs the speed feedforward output 27 from the position command 20 and the gain switching signal 34, and the torque feedforward means 5 Torque feed forward output 28 is output from speed feed forward output 27 and gain switching signal 34. The speed detection means 6 calculates the motor speed 30 from the difference between the samplings of the motor position 29, and the position command speed detection means 7 calculates the position command speed 31 from the difference between the samplings of the position command 20 to determine gain switching. The means 8 outputs a gain switching signal 34 from the position command speed 31, the determination delay time 32, and the determination threshold 33, the determination delay time setting means 9 sets the determination delay time 32, and the determination threshold setting means 10 determines the determination threshold 33. Is set.

  The position control means 1, speed control means 2, speed feed forward means 4 and torque feed forward means 5 have two types of control gains internally, and the first control gain is applied when the gain switching signal 34 is OFF. When ON, the second control gain is applied. This control gain is set in advance by parameter setting or the like.

  When the absolute value of the position command speed 31 is less than or equal to the determination threshold 33 after the determination delay time 32 has elapsed since the absolute value of the position command speed 31 is greater than 0, the gain switching determination means 8 performs gain switching. The signal 34 is turned on. When the absolute value of the position command speed 31 is larger than the determination threshold value 33, the gain switching signal 34 remains off in the initial state. As a result, the gain switching signal 34 is turned off / on only when the position command speed 31 after the determination delay time 32 has not exceeded a certain value, and the gain switching signal 34 remains off otherwise. Can produce. If the absolute value of the position command speed 31 is detected to be larger than 0 to 0 when the gain switching signal 34 is on, the gain switching signal 34 is returned to off.

  Next, it will be described with reference to FIG. 2 whether the difference in position command distance can be accommodated. 2A shows a case where the position command distance is short (short pitch), and FIG. 2B shows a case where the position command distance is long (long pitch). The respective position command speeds 31 are as shown in the figure, and are a triangular wave command for a short pitch and a trapezoidal wave command for a long pitch. When the determination threshold 33 is set to the maximum value at the short pitch and the determination delay time 32 is set to a time during the deceleration of the short pitch, as shown in the figure, the gain switching signal 34 is turned off / on at the short pitch. There is a change and remains off at long pitches. First, the control gain to be applied with the gain switching signal 34 turned off is optimized for the long pitch. Thereafter, for the short pitch, the control gain applied with the gain switching signal 34 turned on is optimized for the short pitch. Since the control gain optimized for the short pitch has no effect on the long pitch, independent optimization can be realized. Further, by finely adjusting the determination threshold value 33 and the determination delay time 32, it is possible to perform adjustment so that switching is performed when the impact at the time of gain switching is small, for example, when the torque command 25 is near 0 or near the motor speed 30.

  In the determination delay time setting means 9 and the determination threshold setting means 10, the determination delay time 32 and the determination threshold 33 may be made variable by parameters or the like so that they can be changed through communication or front panel operation.

  Further, gain switching is performed by the position control means 1, the speed control means 2, the speed feed forward means 4, and the torque feed forward means 5, but the gain switching signal 34 is turned on / off in a portion where the gain is not changed. However, the same control gain setting should be used.

  The position control means 1 generally has a position proportional gain, a position integral gain, the speed control means 2 has a speed proportional gain, a speed integral gain, and the speed feed forward means 4 has a speed feed forward gain, The speed feedforward filter time constant and the torque feedforward means 5 have control gains such as a torque feedforward gain and a torque feedforward filter time constant, and the gain switching signal 34 is turned on and off for each of them. You should have a gain of. In addition to this, it is obvious that control means such as acceleration feedback can be added in accordance with the control system, and gain switching can be similarly performed.

  FIG. 3 is a block diagram of the motor drive device of the second invention. 1, a gain switching duration setting means 11 for setting a gain switching duration 35 is added.

  The basic configuration is the same as that of the first embodiment, and only the differences will be described here. When the absolute value of the position command speed 31 is less than or equal to the determination threshold 33 after the determination delay time 32 has elapsed since the absolute value of the position command speed 31 is greater than 0, the gain switching determination means 8 performs gain switching. The signal 34 is turned on. When the absolute value of the position command speed 31 is larger than the determination threshold value 33, the gain switching signal 34 remains off in the initial state. The gain switching signal 34 is turned off after the gain switching continuation time 35 has elapsed since the gain switching signal 34 was turned on.

  As a result, as shown in FIG. 4, it is possible to arbitrarily set the section in which the gain switching signal 34 is on at the time of a short pitch, so that the degree of freedom in optimizing the control gain can be improved. .

  In the gain switching duration setting means 11, the gain switching duration 35 is made variable by a parameter or the like and can be changed by communication or front panel operation, as in the determination delay time setting means 9 and the determination threshold setting means 10. It is good to do so.

  The motor drive device of the present invention is useful not only for positioning control but also for speed control and the like.

DESCRIPTION OF SYMBOLS 1 Position control means 2 Speed control means 3 Current control means 4 Speed feed forward means 5 Torque feed forward means 6 Speed detection means 7 Position command speed detection means 8 Gain switching determination means 9 Determination delay time setting means 10 Determination threshold setting means 11 Gain Switching duration setting means 20 Position command 21 Position deviation 22 Position control output 23 Speed deviation 24 Speed control output 25 Torque command 26 Current control output 27 Speed feedforward output 28 Torque feedforward output 29 Motor position 30 Motor speed 31 Position command speed 32 Judgment delay time 33 Judgment threshold 34 Gain switching signal 35 Gain switching duration

Claims (2)

A position control means for calculating a position control output so as to converge a position deviation to 0 using a position control gain selected by a gain switching signal in a motor control device for controlling the motor position to follow a position command, and a gain Speed control means for calculating the speed control output so as to converge the speed deviation to 0 using the speed control gain selected by the switching signal, and current control means for calculating the current control output so as to drive the motor according to the torque command Speed feedforward means for calculating the speed feedforward output from the position command using the speed feedforward gain selected by the gain switching signal, and the speed using the torque feedforward gain selected by the gain switching signal. Torque feed to calculate torque feed forward output from feed forward output A forward switch, a speed detector for calculating the motor speed from the motor position, a position command speed detector for calculating the position command speed from the position command, and a gain switching signal based on the position command speed, the determination delay time and the determination threshold value. A gain switching determination means for turning off; a determination delay time setting means for setting a determination delay time; and a determination threshold setting means for setting a determination threshold; a position command speed after the determination delay time has elapsed in the gain switching determination means A motor drive device comprising: a configuration in which a gain switching signal is turned on if the absolute value of is less than or equal to a determination threshold, and the gain switching signal is kept off if greater than the determination threshold. A position control means for calculating a position control output so as to converge a position deviation to 0 using a position control gain selected by a gain switching signal in a motor control device for controlling the motor position to follow a position command, and a gain Speed control means for calculating the speed control output so as to converge the speed deviation to 0 using the speed control gain selected by the switching signal, and current control means for calculating the current control output so as to drive the motor according to the torque command Speed feedforward means for calculating the speed feedforward output from the position command using the speed feedforward gain selected by the gain switching signal, and the speed using the torque feedforward gain selected by the gain switching signal. Torque feed to calculate torque feed forward output from feed forward output A forward switch, a speed detector for calculating the motor speed from the motor position, a position command speed detector for calculating the position command speed from the position command, and a gain switching signal based on the position command speed, the determination delay time and the determination threshold value. A gain switching determination means for setting off, a determination delay time setting means for setting a determination delay time, a determination threshold setting means for setting a determination threshold, and a gain switching duration setting means for setting a gain switching duration. If the absolute value of the position command speed after the determination delay time has passed is less than or equal to the determination threshold by the switching determination means, the gain switching signal is turned on for the gain switching continuation time. The motor drive device which comprises the structure to do.

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