JP2008109781A - Position controller for electromotor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a position controller for electromotor which lessens the deviation between a rotating angle command signal and an actual rotating angle signal also during constant acceleration. <P>SOLUTION: A speed feed forward signal calculating circuit 7 calculates a speed feed forward signal ω<SB>ff</SB>from a rotating angle command signal θ<SB>ms</SB>. A mechanical system simulating circuit 4 approximates a torque transmitting mechanism, a load machine, and a DC motor 11, and outputs a simulated speed signal ω<SB>a</SB>and a simulated rotating angle signal θ<SB>a</SB>from a torque signal τ<SB>2</SB>. A second position control circuit 5 outputs a speed signal ω<SB>2</SB>from θ<SB>ms</SB>and θ<SB>a</SB>. A first speed control circuit 9 outputs a torque signal τ<SB>1</SB>from a speed signal ω<SB>3</SB>and an actual speed signal ω<SB>m</SB>. A second speed control signal 6 controls τ<SB>2</SB>from ω<SB>2</SB>, ω<SB>a</SB>, and ω<SB>ff</SB>. A control means controls the torque of the motor 11, based on τ<SB>1</SB>and τ<SB>2</SB>. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a position control device for a motor (DC motor, induction motor, synchronous motor, linear motor, etc.) that drives a load machine such as a table in a machine tool or an arm of an electric industrial robot.

  The configuration of a conventional position control device will be described with reference to FIG. FIG. 13 is a block diagram showing a conventional position control device disclosed in Patent Document 1, for example. In FIG. 13, the position control device drives a load machine (not shown) via a rotation angle command signal generation circuit 1 that generates a rotation angle command signal of the DC motor 11 and a torque transmission mechanism (not shown). DC motor 11, rotation detector 2 for detecting the rotation speed and rotation angle of DC motor 11, first position control circuit 3, mechanical system simulation circuit 4, second position control circuit 5, and second Speed control circuit 6, adder 8, first speed control circuit 9, adder 10, power conversion circuit 12, and torque control circuit 13.

  Next, with regard to the operation of the above-described conventional position control device, first, a first speed signal is obtained by the first position control circuit 3, and further, a second position control with the mechanical system simulation circuit as a control target. The circuit 5 provides a second speed control signal. Subsequently, a third speed signal, which is the sum of the first speed signal and the second speed signal, is obtained by the adder 8, supplied to the first speed control circuit 9, and then by the first speed control circuit. A first torque signal is obtained. Similarly, when the second speed signal is input to the second speed control circuit 6, a second torque signal is obtained. Further, a third torque signal is output from the third speed control circuit. The control means controls the generated torque of the electric motor to follow the final torque signal obtained by adding the first torque signal, the second torque signal, and the third torque signal.

  Thus, in the conventional position control device, the signals from the second position control circuit, the second speed control circuit, the third speed control circuit, and the mechanical system simulation circuit that are controlled by the mechanical system simulation circuit, In a feed-forward manner, an actual control loop including a first position control circuit, a first speed control circuit, and a torque control circuit is incorporated. By doing so, a control device capable of adjusting the gain with high response without giving an impact to the machine even when the change of the rotation angle command signal is steep is realized.

JP-A-6-30578

  However, the conventional position control device described above cannot suppress the rotational angle position deviation during constant acceleration even though it can suppress the rotational angle position deviation during constant speed.

  Therefore, for example, a mechanical device that is composed of a plurality of shaft motors and that activates the motors of the other shafts while monitoring the actual position of the motors of the predetermined shafts, or a high-accuracy mechanical device. It may be difficult to obtain desired performance for a mechanical device that requires position trajectory control.

  The present invention has been made in view of the above-described problems of the prior art, and has characteristics that it has high-speed response and does not generate mechanical vibrations, and also has a rotation angle command signal and an actual rotation angle even during constant acceleration. An object of the present invention is to provide an electric motor position control device that minimizes signal deviation.

In order to solve the above problems and achieve the object, the electric motor position control device according to the first invention includes the following.
(1) A first position control circuit that outputs a first speed signal based on the rotation angle command signal and the actual rotation angle signal of the electric motor.
(2) A speed feedforward signal calculation circuit that inputs the rotation angle command signal and outputs a speed feedforward signal by a predetermined function calculation including at least one differential calculation.
(3) A mechanical simulation circuit that approximates an electric motor, a torque transmission mechanism, and a load machine as two integral elements and outputs a simulated speed signal and a simulated rotation angle signal.
(4) A second position control circuit that outputs a second speed signal based on the rotation angle command signal and the simulated rotation angle signal.
(5) An adder that adds the first speed signal and the simulated speed signal and outputs a third speed signal.
(6) A first speed control circuit that outputs a first torque signal based on the third speed signal and the actual speed signal of the electric motor.
(7) A second speed control circuit that outputs a second torque signal based on the second speed signal, the simulated speed signal, and the speed feedforward signal.
(8) Control means for controlling the generated torque of the electric motor based on the first torque signal and the second torque signal.

  In addition to the electric motor position control device according to the first invention, the electric motor position control device according to the second invention is a rotation angle command state determination that outputs a rotation angle determination signal from the state of the rotation angle command signal. A first multiplier that outputs a simulated speed conversion signal from the simulated speed signal and the rotation angle determination signal, and a first multiplier that outputs a torque conversion signal from the second torque signal and the rotation angle determination signal. 2 multipliers are provided.

Furthermore, an electric motor position control apparatus according to a third aspect of the present invention includes the following.
(1) A first position control circuit that outputs a first speed signal based on the rotation angle command signal and the actual rotation angle signal of the electric motor.
(2) A speed feedforward signal calculation circuit that inputs the rotation angle command signal and outputs a speed feedforward signal by a predetermined function calculation including at least one differential calculation.
(3) A torque feedforward signal calculation circuit that inputs the speed feedforward signal and outputs a torque feedforward signal by a predetermined function calculation including at least one differential calculation.
(4) A mechanical simulation circuit that approximates an electric motor, a torque transmission mechanism, and a load machine as two integral elements and outputs a simulated speed signal and a simulated rotation angle signal.
(5) A second position control circuit that outputs a second speed signal based on the rotation angle command signal and the simulated rotation angle signal.
(6) A first adder that adds the first speed signal and the simulated speed signal and outputs a third speed signal.
(7) A first speed control circuit that outputs a first torque signal based on the third speed signal and the actual speed signal of the electric motor.
(8) A second speed control circuit that outputs a second torque signal based on the second speed signal, the simulated speed signal, and the speed feedforward signal.
(9) A second adder that adds the second torque signal and the torque feedforward signal and outputs a third torque signal.
(10) Control means for controlling the generated torque of the electric motor based on the first torque signal and the third torque signal.

  Furthermore, the electric motor position control device according to the fourth aspect of the invention includes, in addition to the electric motor position control device according to the third aspect of the invention, a rotation angle command state that outputs a rotation angle determination signal from the state of the rotation angle command signal. A torque conversion signal is output from the determination device, the first multiplier that outputs a simulated speed conversion signal from the simulated speed signal and the rotation angle determination signal, and the second torque signal and the rotation angle determination signal. A second multiplier is provided.

  In the electric motor position control apparatus according to the first aspect of the invention, first, a first speed signal is obtained by the first position control circuit. Further, a simulated speed signal is obtained by the mechanical system simulation circuit. Subsequently, a third speed signal that is the sum of the first speed signal and the simulated speed signal is obtained by an adder, supplied to the first speed control circuit, and the first speed control circuit provides the first torque. A signal is obtained. Similarly, a second speed signal is obtained by the second position control circuit. Moreover, a speed feedforward signal is obtained by the first feedforward signal calculation circuit. The second torque signal is obtained by inputting the second speed signal, the speed feedforward signal, and the simulated speed signal to the second speed control circuit. Further, the actual rotation angle signal and the rotation angle command of the motor are controlled by the control means so that the torque generated by the motor follows the final torque signal obtained by adding the first torque signal and the second torque signal. Acts to minimize signal deviation. As a result, it has high speed response characteristics and does not cause mechanical vibration, and the deviation of the actual rotation angle command signal with respect to the rotation angle command signal during constant acceleration can be suppressed to zero. High position trajectory tracking control can be realized.

  According to a second aspect of the present invention, there is provided a position control device for an electric motor, wherein the position control device for an electric motor according to the first aspect outputs a rotation angle determination signal corresponding to the state of the rotation angle command, and this signal is used as a simulated speed signal. In addition, by multiplying the second torque signal, the deviation between the actual rotation angle signal of the electric motor and the rotation angle command signal does not occur immediately before the rotation angle command signal becomes zero. As a result, in addition to the effect of the electric motor position control device according to the first aspect of the invention, the overshoot at the time of command stop becomes zero, so that high-speed positioning settling can be realized, and high speed can be realized as a whole device Is possible.

  Furthermore, in the electric motor position control apparatus according to the third aspect of the invention, first, the first speed signal is obtained by the first position control circuit. Further, a simulated speed signal is obtained by the mechanical system simulation circuit. Subsequently, a third speed signal that is the sum of the first speed signal and the simulated speed signal is obtained by an adder, supplied to the first speed control circuit, and the first speed control circuit provides the first torque. A signal is obtained. Similarly, a second speed signal is obtained by the second position control circuit. Moreover, a speed feedforward signal is obtained by the first feedforward signal calculation circuit. The second torque signal is obtained by inputting the second speed signal, the speed feedforward signal, and the simulated speed signal to the second speed control circuit. Furthermore, a torque feedforward signal is obtained by the torque feedforward signal calculation circuit, and this signal and the second torque signal are added by an adder to obtain a third torque signal. Further, the control means controls the generated torque of the electric motor to follow the final torque signal obtained by adding the first torque signal and the third torque signal, so that the deviation that occurs when the acceleration changes is controlled. It works to keep it even smaller. Thereby, it is possible to further reduce the amount of deviation that has occurred at the time of acceleration change, and it is possible to realize more accurate position trajectory tracking control in the mechanical device.

  Furthermore, an electric motor position control device according to a fourth aspect of the present invention is the electric motor position control device according to the third aspect of the present invention, which outputs a rotation angle determination signal corresponding to the state of the rotation angle command and uses this signal as a simulated speed. By multiplying the signal and the second torque signal, the deviation between the actual rotation angle signal of the electric motor and the rotation angle command signal is prevented from occurring when the rotation angle command signal becomes zero. As a result, in addition to the electric motor position control device according to the third aspect of the invention, the overshoot at the time of command stop becomes zero, so that high-speed positioning settling can be realized, and the overall speed of the device can be realized. It becomes.

  Embodiments of an electric motor position control apparatus according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment 1 FIG.
Hereinafter, the configuration of the first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a block diagram showing the entirety of the electric motor position control apparatus according to Embodiment 1 of the present invention, and a DC motor 11 and a power conversion circuit 12 are exactly the same as the position control apparatus described above.

In FIG. 1, the position control device of the present embodiment is configured so that a DC motor 11 that drives a load machine (not shown) via a torque transmission mechanism (not shown) is transmitted to the DC motor 11 as a rotation angle command. The rotation angle command signal θ _ms generated by the signal generation circuit 1 and the actual rotation angle signal θ _m and the actual speed signal ω _m detected and output from the DC motor 11 by the rotation detector 2 connected to the DC motor 11. A position control device that performs control based on a first position control circuit 3, a mechanical system simulation circuit 4, a second position control circuit 5, a second speed control circuit 6, and a speed feedforward signal calculation The circuit 7 includes an adder 8, a first speed control circuit 9, an adder 10, a power conversion circuit 12, and a torque control circuit 13. That is, in addition to the conventional position control device shown in FIG. 13, a speed feedforward signal calculation circuit 7 is provided. The adder 8 adds the first speed signal ω ₁ and the simulated speed signal ω _a to output a _third speed signal ω ₃ , and the first speed control circuit 9 The first torque signal τ ₁ is output based on the _third speed signal ω ₃ and the actual speed signal ω _m .

  The rotation detector 2 is composed of, for example, a speed detector such as a tachometer and a position detector such as an encoder (a linear scale when the motor is a linear motor). The torque control means of the DC motor 11 includes a torque control circuit 13 and a power conversion circuit 12.

The rotation angle command signal generation circuit 1 generates a rotation angle command signal θ _ms as a command for driving the DC motor 11. The rotation detector 2 detects the rotation speed and rotation angle of the DC motor 11 and outputs an actual speed signal ω _m and an actual rotation angle signal θ _m . The first position control circuit 3 outputs a _first speed signal ω ₁ based on the rotation angle command signal θ _ms of the DC motor 11 and the actual rotation angle signal θ _m output from the rotation detector 2. The second position control circuit 5 outputs a _second speed signal ω ₂ based on the rotation angle command signal θ _ms and the simulated rotation angle signal θ _a . The speed feedforward signal calculation circuit 7 receives the rotation angle command signal θ _ms of the DC motor 11 and executes a predetermined function calculation including a differential calculation, so that the speed feedforward signal ω is _derived from the rotation angle command signal θ _ms. Calculate _ff . Then, the speed feedforward signal calculation circuit 7 outputs this speed feedforward signal ω _ff . The adder 10 adds the second speed signal ω ₂ and the speed feedforward signal ω _ff and outputs the result to the second speed control circuit 6.

The mechanical system simulation circuit 4 approximates the torque transmission mechanism, the load machine, and the DC motor 11 as two integral elements, and based on a _second torque signal τ ₂ described later, a simulated speed signal ω _a and a simulated rotation angle signal θ _a. Is output.

As described above, the adder 8 adds the first speed signal ω ₁ and the simulated speed signal ω _a and outputs the _third speed signal ω ₃ . The first speed control circuit 9 outputs a _first torque signal τ ₁ based on the third speed signal ω ₃ and the actual speed signal ω _m output from the rotation detector 2. The second speed control circuit 6 outputs a _second torque signal τ ₂ based on the second speed signal ω _{2, the} simulated speed signal ω _a and the speed feed forward signal ω _ff . The control means including the torque control circuit 13 and the power conversion circuit 12 controls the torque of the DC motor 11 based on the first torque signal τ ₁ and the second torque signal τ ₂ .

FIG. 2 is a diagram showing a model of the position control device of the present embodiment. In FIG. 2, a circuit 3 a indicates a model of the first position control circuit 3 in FIG. 1, and a circuit 9 a indicates a model of the first speed control circuit 9. A circuit 4 a represents a model of the mechanical system simulation circuit 4, and a circuit 5 a represents the second position control circuit 5. The circuit 6a shows a model of the second speed control circuit 6, and the circuit 7a shows a model of the speed feedforward signal calculation circuit 7. The circuit 15a shows a model of the combination of the DC motor 11, the rotation detector 2, the torque control circuit 13, and the power conversion circuit 12 of FIG. A circuit 1a shows a model of the rotation angle command signal generation circuit 1. As shown in the circuit 7a, the speed feedforward signal calculation circuit 7 executes a function calculation including a differentiation calculation and calculates a speed feedforward signal ω _ff from the rotation angle command signal θ _ms .

ここで、Ｋ_p1、Ｋ_u、Ｋｉ、Ｋ_p2、Ｋ_v2、ω_vは適当な定数である。 FIG. 14 is a diagram similarly showing the conventional position control apparatus shown in FIG. 13 as a model. 2 and 14, K _p1 (s), K _v1 (s), K _p2 (s), K _v2 (s), and θ _ms (s) indicate transfer functions in a general sense. The principle of the control method of the position control apparatus according to the present embodiment will be described with reference to FIGS. Here, for simplicity, each transfer function is represented by the following equation.

Here, K _p1 , K _u , Ki, K _p2 , K _v2 , and ω _v are appropriate constants.

α_k、β_kは、それぞれ図１４のブロック図を解くことによりＫ_p1、Ｋ_u、Ｋ_i、Ｋ_p2、Ｋ_v2を用いて表される適当な定数であり、少なくともα₁、β₃は０以外の定数である。このような従来の位置制御装置に、一定速回転角指令信号としてθ_ms（ｓ）を次式（６）で与えたとする。

偏差Δθ_ms（ｓ）を逆ラプラス変換して求められる偏差Δθ_ms（ｓ）の時間領域表現をΔθ_ms（ｔ）とおくと、Δθ_ms（ｔ）の定常状態は、最終値の定理により式（５）を用いて、

となる。このことから、図１４（図１３）に示す従来の位置制御装置が、一定速回転角指令信号に対して実回転角信号を偏差なく追従させることができると分かる。 First, the deviation Δθ _ms (s) (= θ _ms (s) −θ _m (s)) in the conventional control method takes the form of the following equation using θ _ms (s).

α _k and β _k are appropriate constants expressed using K _p1 , K _u , K _i , K _p2 , and K _v2 by solving the block diagram of FIG. 14, and at least α ₁ and β ₃ are It is a constant other than 0. It is assumed that θ _ms (s) is given by the following equation (6) as a constant speed rotation angle command signal to such a conventional position control device.

When placing the deviation [Delta] [theta] _ms for a deviation [Delta] [theta] _ms (s) to inverse Laplace transform the time domain representation of the (s) and Δθ _ms (t), the steady state Δθ _ms (t), wherein the theorem final value Using (5)

It becomes. From this, it can be understood that the conventional position control device shown in FIG. 14 (FIG. 13) can follow the actual rotation angle signal without deviation with respect to the constant speed rotation angle command signal.

このときの定常状態におけるΔθ_ms（ｔ）は上記と同様にして最終値の定理を用いると、

となる。このことから、従来の位置制御装置においては、一定速回転角指令信号に対しては、偏差Δθ_ms（ｔ）を０にすることができても、一定加速回転角指令信号に対しては偏差Δθ_ms（ｔ）を０にできないと分かる。 Similarly, it is assumed that a constant acceleration rotation angle command signal is given by the following equation (7) to a conventional position control device.

At this time, Δθ _ms (t) in the steady state is the same as above, and using the final value theorem,

It becomes. Thus, in the conventional position control device, even if the deviation Δθ _ms (t) can be set to 0 for the constant speed rotation angle command signal, the deviation for the constant acceleration rotation angle command signal is It can be seen that Δθ _ms (t) cannot be reduced to zero.

γ_k、ε_kはそれぞれ図２のブロック図を解くことによりＫ_p1、Ｋ_u、Ｋ_i、Ｋ_p2、Ｋ_v2、ω_vを用いて表される適当な定数であり、少なくともε₆は０以外の定数である。このような本実施の形態の位置制御装置に対して、回転角指令信号を上記の式（７）で与えたとき、このときの定常状態におけるΔθ_ms（ｔ）は最終値の定理により式（８）を用いて、

となる。このことから、本実施の形態の位置制御装置が、一定加速回転角指令に対しても実回転角信号を偏差なく追従させることができると分かる。 On the other hand, when the position control device of the present embodiment shown in FIG. 2 (FIG. 1) is used, the deviation Δθ _ms (s) is obtained as the form of the following equation using θ _ms (s).

γ _k and ε _k are appropriate constants expressed using K _p1 , K _u , K _i , K _p2 , K _v2 , and ω _v by solving the block diagram of FIG. 2, and at least ε ₆ is 0. It is a constant other than. When the rotation angle command signal is given by the above equation (7) to the position control device of the present embodiment, Δθ _ms (t) in the steady state at this time is expressed by the equation ( 8)

It becomes. From this, it can be understood that the position control apparatus of the present embodiment can follow the actual rotation angle signal without deviation even with respect to the constant acceleration rotation angle command.

FIG. 3 shows a waveform of the deviation Δθ _ms (t) when using the first embodiment. However, if the rotation angle command signal θ _ms is given as shown in FIG. 15, the speed command signal which is a one-time differentiation thereof has a trapezoidal waveform as shown in the graph of FIG. As can be seen from FIG. 3, the deviation Δθ _ms (t) during constant acceleration is zero.

In such a position control device of the present embodiment, the first speed signal ω ₁ is obtained by the first position control circuit 3. Further, the simulated speed signal ω _a is obtained by the mechanical system simulation circuit 4. Next, _a third speed signal ω _3, which is the sum of the first speed signal ω ₁ and the simulated speed signal ω _a , is obtained by the adder 8 and supplied to the first speed control circuit 9 for the first speed. A first torque signal τ ₁ is obtained by the control circuit 9.

Similarly, a second speed signal ω ₂ is obtained by the second position control circuit 5. Further, the _first feedforward signal calculation circuit 7 obtains the speed feedforward signal ω _ff . The second torque signal τ ₂ is obtained by inputting the second speed signal ω ₂ , the speed feed forward signal ω _ff, and the simulated speed signal ω _a to the second speed control circuit 6.

The generated torque of the DC motor 11 follows the final torque signal obtained by adding the first torque signal τ ₁ and the second torque signal τ ₂ by the control means including the torque control circuit 13 and the power conversion circuit 12. By controlling in this way, the operation is performed so that the deviation between the actual rotation angle signal θ _m of the DC motor 11 and the rotation angle command signal θ _ms is minimized.

For this reason, the position control device according to the present embodiment has characteristics of high-speed response and no mechanical vibration, and the actual rotation angle command signal for the rotation angle command signal θ _ms during constant acceleration. The deviation can be suppressed to 0, and highly accurate position trajectory tracking control can be realized in the mechanical device.

  Note that the motor controlled by the position control device of the present embodiment is not limited to a DC motor, and any motor such as an induction motor, a synchronous motor, or a linear motor can be controlled.

Embodiment 2. FIG.
The configuration of the second embodiment of the present invention will be described below with reference to FIGS. FIG. 4 is a block diagram showing the entirety of the position control apparatus for an electric motor according to Embodiment 2 of the present invention. In the position control device of the present embodiment, in addition to the position control device of the first embodiment, a rotation angle command state determiner 100 that outputs a rotation angle determination signal from the state of the rotation angle command signal θ _ms , and a simulated speed A first multiplier 101 that outputs a simulated speed conversion signal ω _at from the signal ω _a and the rotation angle determination signal, and a second multiplier that outputs a torque conversion signal τ _2t from the second torque signal τ ₂ and the rotation angle determination signal. A multiplier 102 is provided.

FIG. 5 is a diagram showing a model of the electric motor position control apparatus according to the present embodiment. In FIG. 5, circuits 101a and 102a are models of the first multiplier 101 and the second multiplier 102 in FIG. 4, respectively. The rotation angle command state determiner 100 receives the rotation angle command signal θ _ms, and outputs a determination signal (rotation angle determination signal) of “1” when the change amount of the rotation angle command signal θ _ms is other than 0. When the change amount of the rotation angle command signal θ _ms is 0, a determination signal (rotation angle determination signal) of “0” is output.

The first multiplier 101 multiplies the simulated speed signal ω _a by the rotation angle determination signal and outputs a simulated speed conversion signal ω _at . The second multiplier 102 multiplies the second torque signal τ ₂ and the rotation angle determination signal and outputs a torque conversion signal τ _2t . The adder 8 adds the first speed signal ω ₁ and the simulated speed conversion signal ω _at to output a _third speed signal ω ₃ . The first speed control circuit 9 outputs a _first torque signal τ ₁ based on the third speed signal ω ₃ and the actual speed signal ω _m output from the rotation detector 2. The control means comprising the torque control circuit 13 and the power conversion circuit 12 controls the torque of the DC motor 11 based on the first torque signal τ ₁ and the torque conversion signal τ _2t . Other configurations are the same as those of the first embodiment.

A waveform of the deviation Δθ _ms (t) when using the second embodiment is shown in FIG. However, if the rotation angle command signal θ _ms is given as shown in FIG. 15, the speed command signal which is a one-time differentiation thereof has a trapezoidal waveform as shown in the graph of FIG. As can be seen from FIG. 6, in addition to the deviation Δθ _ms (t) during constant acceleration being 0, an overshoot occurs when the speed command signal is 0, that is, the amount of change in the rotation angle command signal is 0. You can see that they are not.

Thus, in the electric motor position control apparatus of the present embodiment, rotation angle command state determination unit 100 outputs a rotation angle determination signal corresponding to the state of rotation angle command signal θ _ms , and simulates this signal. and speed signal omega _a is multiplied with the second torque signal tau _2, the actual rotational angle signal theta _m and the rotation angle command signal theta _ms deviation of the rotation angle command signal theta _ms DC motor just before becomes 0 11 It works so as not to occur. For this reason, in addition to the effects of the first embodiment, the overshoot at the time of command stop becomes zero, so that high-speed positioning settling can be realized, and the overall speed of the apparatus can be realized.

Embodiment 3 FIG.
The configuration of the third embodiment of the present invention will be described below with reference to FIGS. FIG. 7 is a block diagram showing the entire position control apparatus for an electric motor according to Embodiment 3 of the present invention. In the position control device of the present embodiment, in addition to the position control device of the first embodiment, a torque feedforward signal calculation circuit 17 and a second adder 16 are provided. Then, a third torque signal τ _{3 obtained} by adding the torque feed forward signal τ _ff output from the torque feed forward signal calculation circuit 17 and the second torque signal τ ₂ is input to the mechanical system simulation circuit 4 and the torque control circuit 13. The

FIG. 8 is a diagram showing a model of the electric motor position control apparatus according to the present embodiment. In FIG. 8, a circuit 17 a indicates a model of the torque feedforward signal calculation circuit 17. The torque feed forward signal calculation circuit 17 receives the speed feed forward signal ω _ff and executes a predetermined function calculation including a differential calculation, thereby calculating the torque feed forward signal τ _ff from the speed feed forward signal ω _ff. The torque feed forward signal τ _ff is output. The second adder 16 adds the second torque signal τ ₂ and the torque feedforward signal τ _ff and outputs a _third torque signal τ ₃ . The mechanical system simulation circuit 4 outputs _a simulated speed signal ω _a and a simulated rotation angle signal θ _m based on the third torque signal τ ₃ . The control means comprising the torque control circuit 13 and the power conversion circuit 12 controls the torque of the DC motor 11 based on the first torque signal τ ₁ and the third torque signal τ ₃ . Other configurations are the same as those of the first embodiment.

FIG. 9 shows a waveform of the deviation Δθ _ms (t) when the third embodiment is used. However, if the rotation angle command signal is given as shown in FIG. 15, the speed command signal, which is a derivative of the rotation angle, has a trapezoidal waveform as shown in the graph of FIG. As can be seen from FIG. 9, the deviation Δθ _ms (t) during constant acceleration is 0, and the amount of overshoot generated when the speed command signal is switched is reduced compared to the first embodiment. You can see that

In the position control apparatus of the present embodiment, the first speed signal ω ₁ is obtained by the first position control circuit 3. Further, the simulated speed signal ω _a is obtained by the mechanical system simulation circuit 4. Next, _a third speed signal ω _3, which is the sum of the first speed signal ω ₁ and the simulated speed signal ω _a , is obtained by the adder 8 and supplied to the first speed control circuit 9 for the first speed. A first torque signal τ ₁ is obtained by the control circuit 9.

Similarly, a second speed signal ω ₂ is obtained by the second position control circuit 5. Further, the first feedforward signal calculation circuit 7 obtains the speed feedforward signal ω _ff . The second torque signal τ ₂ is obtained by inputting the second speed signal ω ₂ , the speed feed forward signal ω _ff, and the simulated speed signal ω _a to the second speed control circuit 6.

Further, a torque feedforward signal τ _ff is obtained by the torque feedforward signal calculation circuit 17, and this signal and the second torque signal τ ₂ are added by the second adder 16 to obtain a third torque signal τ _3. can get. Further, the generated torque of the DC motor 11 follows the final torque signal obtained by adding the first torque signal τ ₁ and the third torque signal τ ₃ by the control means including the torque control circuit 13 and the power conversion circuit 12. Thus, the deviation generated when the acceleration changes is operated to be further suppressed to the minimum as compared with the first embodiment. As a result, position trajectory tracking control with higher accuracy can be realized in the mechanical device.

Embodiment 4 FIG.
The configuration of the fourth embodiment of the present invention will be described below with reference to FIGS. FIG. 10 is a block diagram showing an entire position control apparatus for an electric motor according to Embodiment 4 of the present invention. In the position control device of the present embodiment, in addition to the position control device of the second embodiment, a torque feedforward signal calculation circuit 17 and a second adder 16 of the third embodiment are provided. FIG. 11 is a diagram showing a model of the electric motor position control apparatus according to the present embodiment.

The torque feed forward signal calculation circuit 17 inputs the speed feed forward signal ω _ff and outputs the torque feed forward signal τ _ff by a predetermined function calculation including differentiation. The second adder 16 adds the second torque signal τ ₂ and the torque feedforward signal τ _ff and outputs a _third torque signal τ ₃ . The second multiplier 102 multiplies the third torque signal τ ₃ and the rotation angle determination signal and outputs a torque conversion signal τ _3t . The control means comprising the torque control circuit 13 and the power conversion circuit 12 controls the torque of the DC motor 11 based on the first torque signal τ ₁ and the torque conversion signal τ _3t . Other configurations are the same as those of the second embodiment.

FIG. 12 shows a waveform of the deviation Δθ _ms (t) when using the fourth embodiment. However, if the rotation angle command signal is given as shown in FIG. 15, the speed command signal, which is a single derivative thereof, has a trapezoidal waveform as shown in the graph of FIG. As can be seen from FIG. 12, the deviation Δθ _ms (t) during constant acceleration has the same effect as in the third embodiment, and in addition, the overshoot immediately before the speed command signal becomes 0, that is, the rotation angle command signal becomes 0. It turns out that does not occur.

In the position control device of the present embodiment, the rotation angle command state determiner 100 outputs a rotation angle determination signal corresponding to the state of the rotation angle command signal θ _ms , and this signal is used as the simulated speed signal ω _a and the second speed signal. The torque signal τ ₂ is multiplied so that the deviation between the actual rotation angle signal θ _m of the DC motor 11 and the rotation angle command signal θ _ms does not occur _immediately before the rotation angle command signal θ _ms becomes zero. For this reason, in addition to the effects of the third embodiment, the overshoot at the time of command stop becomes zero, so that high-speed positioning settling can be realized, and the entire apparatus can be increased in speed.

  An electric motor position control device according to the present invention controls an electric motor that drives a load machine via a torque transmission mechanism based on a rotation angle command signal, an actual rotation angle signal detected from the motor, and an actual speed signal. The present invention is suitable for application to a position control device, and is suitable for application to a position control device for an electric motor that drives a load machine such as a table in a machine tool or an arm of an electric industrial robot.

1 is a block diagram illustrating an entire position control device for an electric motor according to a first embodiment. It is a figure which models and shows the position control apparatus of the electric motor of Embodiment 1. FIG. It is a graph which compares and shows the deviation amount of the position control apparatus of the electric motor of Embodiment 1, and the deviation amount of a conventional apparatus. It is a block diagram which shows the whole position control apparatus of the electric motor of Embodiment 2. FIG. It is a figure which models and shows the position control apparatus of the electric motor of Embodiment 2. FIG. It is a graph which compares and shows the deviation amount of the position control apparatus of the electric motor of Embodiment 2, and the deviation amount of a conventional apparatus. FIG. 6 is a block diagram showing an entire position control apparatus for an electric motor according to a third embodiment. It is a figure which models and shows the position control apparatus of the electric motor of Embodiment 3. FIG. It is a graph which compares and shows the deviation amount of the position control apparatus of the electric motor of Embodiment 3, and the deviation amount of a conventional apparatus. FIG. 10 is a block diagram illustrating an entire position control apparatus for an electric motor according to a fourth embodiment. It is a figure which models and shows the position control apparatus of the electric motor of Embodiment 4. FIG. It is a graph which compares and shows the deviation amount of the position control apparatus of the electric motor of Embodiment 4, and the deviation amount of a conventional apparatus. It is a block diagram which shows the whole conventional position control apparatus of an electric motor. It is the figure which models and shows the conventional position control apparatus of the electric motor. It is a graph which shows the waveform of the rotation angle command signal given to the position control apparatus of Embodiment 1-4.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rotation angle command signal generation circuit 1a Rotation angle command signal generation circuit model 2 Rotation angle detector 3 First position control circuit 3a First position control circuit model 4 Mechanical system simulation circuit 4a Mechanical system simulation circuit model 5 Second position control circuit 5a Model of second position control circuit 6 Second speed control circuit 6a Model of second speed control circuit 7 Speed feedforward signal calculation circuit 7a Model of speed feedforward signal calculation circuit 8 Adder (First adder)
9 First speed control circuit 9a Model of first speed control circuit 11 DC motor (motor)
12 Power conversion circuit (control means)
13 Torque control circuit (control means)
14 Third speed control circuit 15a Torque control circuit, power conversion circuit, motor and rotation detector model 16 Adder (second adder)
DESCRIPTION OF SYMBOLS 17 Torque feedforward arithmetic circuit 17a Model of torque feedforward arithmetic circuit 100 Rotation angle command state determination device 101 1st multiplier 101a 1st multiplier model 102 2nd multiplier 102a 2nd multiplier model

Claims (5)

A motor position control device that controls a motor that drives a load machine based on a position command signal commanded to the motor, and an actual position signal and an actual speed signal detected from the motor,
A first position control circuit that outputs a first speed signal based on the position command signal and the actual position signal;
A speed feedforward signal calculation circuit that inputs the position command signal and outputs a speed feedforward signal by a predetermined function calculation including at least one differential calculation;
A mechanical simulation circuit that approximates the load machine and the electric motor as two integral elements and outputs a simulated speed signal and a simulated position command signal based on a second torque signal described later;
A second position control circuit for outputting a second speed signal based on the position command signal and the simulated position command signal;
An adder that adds the first speed signal and the simulated speed signal to output a third speed signal;
A first speed control circuit that outputs a first torque signal based on the third speed signal and the actual speed signal;
A second speed control circuit that outputs a second torque signal based on the second speed signal, the simulated speed signal, and the speed feedforward signal;
And a control means for controlling the torque of the electric motor based on the first torque signal and the second torque signal. A motor position control device that controls a motor that drives a load machine based on a position command signal commanded to the motor, and an actual position signal and an actual speed signal detected from the motor,
A first position control circuit that outputs a first speed signal based on the position command signal and the actual position signal;
A speed feedforward signal calculation circuit that inputs the position command signal and outputs a speed feedforward signal by a predetermined function calculation including at least one differential calculation;
A mechanical simulation circuit that approximates the load machine and the electric motor as two integral elements and outputs a simulated speed signal and a simulated position command signal based on a second torque signal described later;
A second position control circuit for outputting a second speed signal based on the position command signal and the simulated position command signal;
An adder that adds the first speed signal and a simulated speed conversion signal described later to output a third speed signal;
A position command state determiner that outputs a position command determination signal based on the position command signal;
A first multiplier for multiplying the simulated speed signal by the position command determination signal and outputting a simulated speed conversion signal;
A second multiplier that multiplies the second torque signal and the position command determination signal to output a torque conversion signal;
A first speed control circuit that outputs a first torque signal based on the third speed signal and the actual speed signal;
A second speed control circuit that outputs a second torque signal based on the second speed signal, the simulated speed signal, and the speed feedforward signal;
And a control means for controlling the torque of the electric motor based on the first torque signal and the torque conversion signal. A motor position control device that controls a motor that drives a load machine based on a position command signal commanded to the motor, and an actual position signal and an actual speed signal detected from the motor,
A first position control circuit that outputs a first speed signal based on the position command signal and the actual position signal;
A speed feedforward signal calculation circuit that inputs the position command signal and outputs a speed feedforward signal by a predetermined function calculation including at least one differential calculation;
A torque feedforward signal calculation circuit that inputs the speed feedforward signal and outputs a torque feedforward signal by a predetermined function calculation including at least one differential calculation;
A mechanical simulation circuit that approximates the load machine and the electric motor as two integral elements and outputs a simulated speed signal and a simulated position command signal based on a third torque signal described later;
A second position control circuit for outputting a second speed signal based on the position command signal and the simulated position command signal;
A first adder that adds the first speed signal and the simulated speed signal to output a third speed signal;
A first speed control circuit that outputs a first torque signal based on the third speed signal and the actual speed signal;
A second speed control circuit that outputs a second torque signal based on the second speed signal, the simulated speed signal, and the speed feedforward signal;
A second adder that adds the second torque signal and the torque feedforward signal to output a third torque signal;
And a control means for controlling the torque of the electric motor based on the first torque signal and the third torque signal. A motor position control device that controls a motor that drives a load machine based on a position command signal commanded to the motor, and an actual position signal and an actual speed signal detected from the motor,
A first position control circuit that outputs a first speed signal based on the position command signal and the actual position signal;
A speed feedforward signal calculation circuit that inputs the position command signal and outputs a speed feedforward signal by a predetermined function calculation including at least one differential calculation;
A torque feedforward signal calculation circuit that inputs the speed feedforward signal and outputs a torque feedforward signal by a predetermined function calculation including at least one differential calculation;
A mechanical simulation circuit that approximates the load machine and the electric motor as two integral elements and outputs a simulated speed signal and a simulated position command signal based on a third torque signal described later;
A second position control circuit for outputting a second speed signal based on the position command signal and the simulated position command signal;
A position command state determiner that outputs a position command determination signal based on the position command signal;
A first multiplier for multiplying the simulated speed signal by the position command determination signal and outputting a simulated speed conversion signal;
A second multiplier for outputting a torque conversion signal by multiplying a third torque signal described later and the position command determination signal;
A first adder that adds the first speed signal and the simulated speed signal to output a third speed signal;
A first speed control circuit that outputs a first torque signal based on the third speed signal and the actual speed signal;
A second speed control circuit that outputs a second torque signal based on the second speed signal, the simulated speed signal, and the speed feedforward signal;
A second adder that adds the second torque signal and the torque feedforward signal to output a third torque signal;
And a control means for controlling the torque of the electric motor based on the first torque signal and the torque conversion signal. The position command state determiner outputs a position command determination signal of “1” when the change amount of the position command signal is other than 0, and a position of “0” when the change amount of the position command signal becomes 0. The motor position control device according to claim 2 or 4, wherein a command determination signal is output.

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