JPH04278609A - Motor controller - Google Patents

Abstract

PURPOSE:To ensure the active control of a motor regardless of the change of a load side machine system by performing a robust operation based on the torque meter information. CONSTITUTION:In regard of the constitutions of a stabilizing device 1 and a control subject 10, the value obtained by multiplying the drive side application input value by a drive side numerical formula model is subtracted together with the value obtained by multiplying the output value of a torque meter which detects the torque of a twist system by an adverse function of the numerical formula model of the twist system and the numerical formula models of both drive and load sides and then adding together these function and models. Then the result of the subtraction is fed back to the application input value of the drive side control subject.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a vibration suppression method when a so-called torsional system exists between an electric motor and a load, and performs high-speed and robust stabilization control in controlling the load side of the torsional system. The present invention relates to an electric motor control device.

0002

2. Description of the Related Art An example of a general electric motor speed control system will be described with reference to FIG. FIG. 8 shows a stabilizing feedback control device having a conventional PI control system, where 1 is a stabilizing device and 2 is an object to be controlled. Here, R and Y are a command input and a state quantity, respectively. Therefore, in the speed control system example, R is a speed command and Y is a speed detection output. KT is the torque generation coefficient. Thus command input R, state quantity Y
The speed control is stabilized by applying the deviation E to the controlled object 2 through the stabilizing device 1. The stabilizing device 1 is generally constructed as a P (proportional) I (integral) control device.

The example shown in FIG. 8 is a case where the drive side and the load side are rigidly connected, and FIG. 9 shows an example where they are connected by a torsion shaft.

FIG. 9 shows a conventional P
The figure shows a case where an I control system is applied, where 3 is an acceleration/deceleration regulator, 4 is a PI control device, 5 is a limiter, and 6 is a controlled object. Here, ω* is the command input, ω1* is the speed command, ωM is the electric speed, ωL is the load speed, θ is the torsion, KC is the torsion spring coefficient, and TL is the load disturbance. That is, the controlled object 6 has a driving side motor 61, a torsion shaft 62, and a load 63 as main components, and this controlled object 6 has a driving side and a load side, and the torsion shaft 62 exists between them.

[0005]

[Problems to be Solved by the Invention] In the system shown in FIG. 9, if the controlled object including the torsion system is controlled by PI control as in the past, the response speed will be slowed down in order to improve stability. Normally, this is done to prevent vibration. This response speed must be determined by considering the torsional resonance system to be controlled, and its adjustment is extremely difficult, and the response is slow and cannot be said to be a highly functional control method.

An example of simulation data showing the situation during this period is shown in FIG. In other words, in response to the load side speed ωL at the end of the twist, the electric side speed ω on the drive side
Since it is stabilized by combining M and slowing down,
The amount of variation in the load side speed ωL when the load suddenly changes becomes large. It is clear that if you try to adjust this to a faster response, the system will become an oscillating system and stability will not be maintained.

On the other hand, the present applicant has proposed ``Multifunctional Control Device'' in Japanese Patent Application Laid-Open No. 3-25505 and a patent application ``Speed Control Device'' filed on January 31, 1990. The main points of such a proposal are shown in block diagrams as shown in FIGS. 11 to 13. Figure 11, Figure 12 and Figure 1
3, 7 is a feedforward compensation section, and 8 is an equivalent disturbance compensation section. Here, the subscript (N) of the code indicates a nominal value.

Furthermore, when these high-performance control methods are applied to the above-mentioned torsional system, a system as shown in FIG. 14 is obtained. FIG. 14 shows the equivalent disturbance compensation function added, 51, 52,
53 is a limiter, and 9 is a stabilizing device such as fixed P, PI, VSS-PI, etc. In the figures, the same reference numerals as in FIGS. 8 to 13 indicate parts having the same functions. However, if the proposed high-performance control method is simply applied to a torsional system as shown in the block configuration of FIG. is stable, but the load side speed ωL is not. This is because the control targets only the motor-driven side speed ωM, and the operation beyond the torsion is not subject to control.

Figure 10 shows a simulation of the situation during this time.
A similar diagram is shown in FIG. 15. That is, as shown in the figure, although the motor speed ωM, which is the controlled object, is stable, the load side speed ωL, which is not the controlled object, continues to oscillate.

[0010] Furthermore, the present applicant has attempted to improve these problems and is proposing a patent application entitled ``Electric Motor Control Device'' filed on April 27, 1990. In other words, the purpose of this proposal is as follows. a first equivalent disturbance compensation means configured to calculate a first equivalent disturbance from the applied input amount and the state quantity and add it to the applied input amount; and a load side controlled object mechanically coupled to the drive side controlled object. A second equivalent disturbance is calculated from the input input amount and the state quantity, and the output thereof is fed back to the input side of the drive-side controlled object through an inverse function of the drive-side controlled object.
equivalent disturbance compensating means, and non-interfering means configured to prevent the second equivalent disturbance compensation from interfering with the stabilization feedback control device and the first equivalent disturbance compensating means.

However, in such a proposal, information on the driving side speed and the load side speed is required in order to obtain robustness against load fluctuations and parameter fluctuations. Speed information can be easily detected using a daco generator, pulse generator, etc., but the problem is when the drive side and load side are connected in a torsion system and via a speed reducer. At this time, the load side speed must be multiplied by the reciprocal of the reduction ratio in the calculation relationship with the drive side speed, and in applications where the reduction ratio changes variously, it is necessary to always recognize this value, and in practice It often causes trouble. In particular, if the speed reducer is a so-called automatic transmission, control may become impossible.

0012

[Means for Solving the Problems] The present invention has been made in view of the above-mentioned points, and will be described in detail below with reference to the drawings. However, the present invention is basically based on the basic technical idea that robust control can be performed by utilizing torque meter information provided in the torsion system without using load side speed information.

FIG. 1 is a basic block diagram of a torsion system shown to facilitate understanding of the basic technical idea of the present invention. In order to simplify the explanation, we will explain the main control system using torque control (
ATR).

Here, 3 is an acceleration/deceleration regulator, 7 is a feedforward compensator, and 9 is a stabilizing device. Also, 10
is the controlled object (11 is the drive side, 12 is the torsion system, and 13 is the load side). T*, T1*, T2* are torque commands, K
T is the torque generation coefficient, JM and DM are the inertia and viscous resistance of the driving side, ωM and ωL are the speed of the driving side and the speed of the load side, TTM is the torque meter, KC is the torsion spring constant, DV
is the torsional loss, and TL is the load disturbance.

The system shown in FIG. 1 is almost the same as the system shown in FIG.
Therefore, the feedback of the main control system is taken from the torque meter TTM, and stabilization is attempted without using information from the load side speed ωL as shown in Fig. 9. . The feedforward compensator 7 uses an inverse function of the transfer function between the torque command T2* of the 10 inputs to be controlled and the torque meter TTM, so that the torque meter TTM calculates the torque of the torque command T* after passing through the acceleration/deceleration regulator 3. It performs the operation according to the command T1*. The acceleration/deceleration regulator 3 is provided for the purpose of noise cutting and preventing the stabilizing device 9 from entering saturation due to excessive input.

Here, the controlled object 10 is a two-mass point motion system including a torsional system, and its equations of motion are Equations (1) to (2). (T2*・KT-TTM)/(JM S+D
M )=ωM ・・・・・・・・・ ■ (ω
M-ωL)・(A+DV)=TTM...
・・・・・・・・・■ However, A=KC/
S (TTM-TL)/(JLS+DL)=
ωL ・・・・・・・・・・・・ ■

The following equation is derived from equations (1) to (2). [(T2*・KT)/(JM S+DM)
]+[TL+(JLS+DL)]={[
1/(A+DV)]+[1/(JMS+DM)]
+[1/(JL S+DL)]}T
TM・・・・・・・・・・・・・ ■

Therefore, the block portion between (T2* and TTM) in FIG. 1 is as shown in FIG. Furthermore, by performing equivalent disturbance compensation as shown in FIGS. 2 and 3, the torsion system can be made robust against load disturbances and parameter fluctuations. Figure 3
The subscript (N) of the sign in is the nominal value of each parameter, and T is the first-order filter constant. The proof of such robustness will be described later, but the purpose of compensating in the form of partial fractions is to facilitate softening in the target system.

[0019]

[Operation] First, the robustness of FIG. 3 will be proven. When we expand the basic formula ■, we get the formula ■. T2*・KT (JL S+DL) (DV
S+KC) +TL (JM S+DM
) (DV S+KC) = [S(JM S+D
M)(JLS+DL)+(DVS
+KC)(JLS+DL)+(DV
S+KC) (JM S+DM)] TTM...
・・・・・・ ■

[0020] In equation (2), each parameter is a nominal value (N) and a fluctuation value (△), and the equivalent disturbance TDS is calculated by including all fluctuation value terms and load disturbance TL terms.
Expression (■) becomes expression (■). T2*・KTN(JLNS+DLN)+TDS
= [S(JMNS+DMN)(JLN+DLN)+(D
VNS+KCN)(JLNS+DLN)+(D
VNS+KCN) (JMNS+DMN)] TTM...
・・・・・・・・・ ■

[0021] On both sides, 1/[DVNS+KCN) (JMNS+DMN
) (JLNS+DLN)]... Multiplying ■,
The formula becomes ■. [(T2*・KTN)/(JMNS+DMN)
]+TDS' = {[S/(DVNS+KCN)
]+[1/(JMN+DMN)]+[1/
(JLNS+DLN)〕}TTM・・・・・・・・・・
...... ■However, TDS'=TDS/[(DVNS+KCN)(
JMNS+DMN) (JLNS+DLN)]

0022
]A block diagram showing the progress during this period is shown in FIG. As a result, equivalent disturbance compensation is completed, and therefore the block shown in FIG. 5 is obtained, which can be shown as a block diagram expressed only by nominal values completely unrelated to load fluctuations and parameter fluctuations.

FIG. 6 shows a simulation example of the torque response, in which (a) shows the case when the equivalent disturbance compensation shown in FIG. In the figure, the feedforward compensator 7 is removed. Thus, it is clear that the effects of the present invention are significant.

[0024]

Embodiment FIG. 7 shows an example of the main hardware configuration for the main blocks shown in FIGS. 1 and 3. That is, the command input T* is changed by operating a command setter, etc., and is made into the command output T1* through an acceleration/deceleration regulator.

The deviation E between the command output T1* input and the output, which is a part of the state quantity, is stabilized and compensated by the stabilizing device 1 or the like, and the output becomes T2*. By passing T2* through the power actuator, it is multiplied by the gain KT and becomes the driving force for the controlled object. In feedforward compensation, the command output T1* is input, and the output is added to the stabilization compensation output. On the other hand, in equivalent disturbance compensation, T3*
and TTM are input, and the calculation result is also added to the output of the stabilization compensation.

Here, the CPU can be realized by a general-purpose CPU, but if a faster response is required, a digital signal processor (DSP) can be used to achieve a speed of 20 (μS).
) sampling.

[0027]

As described in detail above, the present invention aims to reduce the torque of the drive-side power actuator in order to realize high-speed and robust control of mechanical systems with torsional loads that are not affected by load fluctuations or parameter fluctuations. By applying equivalent disturbance compensation from the command and torque meter information added to the torsion system and using a special method that can ignore the influence of the reducer installed on the load side, it is more active than conventional PI control. It is possible to provide a device that can perform precise control.

The basic principle is based on the equivalent disturbance compensation theory, and when realized on the target CPU, a simple configuration using a new algorithm can achieve high reliability and low cost, making it suitable for industrial use. His contribution to a wide range of fields is extremely large. In addition, in order to facilitate the explanation of the present invention, the main control system is based on ATR, but other applications such as AS
It goes without saying that the same effect can be obtained even when applied to R.

[0029]

[Brief explanation of the drawing]

FIG. 1 is a basic block diagram of a torsion system shown for explaining the basic technical idea of the present invention.

FIG. 2 is a converted block diagram of a torsion system from torque input to torque meter according to the present invention.

FIG. 3 is a block diagram showing an equivalent disturbance compensation enclosure according to the present invention.

FIG. 4 is a block diagram shown for explaining FIG. 3;

FIG. 5 is a block diagram shown for explaining FIG. 3;

FIG. 6 is a waveform diagram showing an example of torque response simulation, in which (a) shows a case where the present invention is applied, and (b) shows a case where a conventional method is used.

FIG. 7 is a diagram showing the main hardware configuration according to the embodiment of the present invention.

FIG. 8 is a block diagram showing a conventional PI control system.

FIG. 9 is a block diagram showing a case where a conventional PI control system is applied to a controlled object including a torsion system.

FIG. 10 is a waveform diagram showing the response waveform according to FIG. 9;

FIG. 11 is a block diagram showing an example proposed by the present applicant.

FIG. 12 is a block diagram showing a first equivalent disturbance compensator proposed by the present applicant.

FIG. 13 is a block diagram showing the drive-side controlled object after compensation shown in FIG. 12;

FIG. 14 is a block diagram showing an example in which first equivalent disturbance compensation is applied to a controlled object including a torsional system.

FIG. 15 is a waveform diagram showing an example of the response waveform of FIG. 14;

[0030]

[Explanation of symbols]

1 Stabilization device 2 Controlled object 3 Acceleration/deceleration regulator 4 PI control device 5 Limiter 6 Controlled object 7 Feedforward compensator 8
Equivalent disturbance compensator 9 Stabilizing device 10 Controlled object T* Torque command T1* Torque command T2* Torque command ωM Drive side speed ωL Load side speed KC Torsion spring constant TTM Torque meter TL Load disturbance DV Torsional system loss

Claims (1)

[Claims] 1. A stabilizing feedback control device for stabilizing and amplifying the deviation between a command input and a state quantity of a drive-side controlled object and inputting it to the controlled object; The load side is configured to have a torque meter for detecting the torque of the torsional system, which is coupled to the load side via the drive side, and an amount obtained by multiplying the input input amount on the drive side by a mathematical model of the drive side and the output amount of the torque meter. The inverse function of the mathematical model of the torsional system and the mathematical model of each of the driving side and the load side are multiplied and added, and the resulting amount is subtracted, and the resulting amount is passed through a primary filter to obtain the applied input amount to the controlled object on the driving side. An electric motor control device characterized in that the motor returns to