JPS62166791A - Motor stopping control device - Google Patents

Abstract

PURPOSE:To perform transferring between a stop state and a speed control state smoothly in a motor, by a method wherein torque command value at the motor stop time is held and correction signal obtained at the position control system is added and then transferred to the stopping control, and the correction signal is separated and transferred to the speed control. CONSTITUTION:A two-phase pulse oscillator 3 generates signal with frequency proportional to rotational speed of a motor 2. A frequency/voltage signal converter (FV) 4 outputs DC voltage proportional to frequency of the output of the two-phase pulse oscillator 3, and FV 5 outputs DC voltage proportional to frequency of the speed setting signal. These outputs are supplied to an operational unit 6 where speed difference signal is outputted and supplied through an amplifier 7 to an operation unit 15. The operation unit 15 adds the speed proportional operation signal to the correction signal, and supplies the gate signal through an amplifier 16, an operation unit 18 and a current operation adjusting device 19 to a power conversion member 1.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides a drawing machine for producing polyester fiber, etc.
The present invention relates to an electric motor drive device that moves, and particularly to an electric motor stop control device that has stop-holding operation and maintenance associated with speed control operation.

[Conventional technology and problems]

Generally speaking, when a drawing machine or the like in a polyester fiber manufacturing machine is operated by an electric motor, an electric motor drive device is used which has a speed control function that can simply drive the electric motor at a variable speed, although it has a stop and hold state. When the speed reaches zero, a mechanical braking device is used to stop the motor, or no braking is applied and the motor is kept at a standstill due to mechanical loss.

However, according to the above-mentioned conventional systems, when the motor starts up or stops between zero speed and a predetermined rotational speed, a sudden change point occurs in the motor speed, resulting in problems such as product unevenness. Particularly when a mechanical braking device is required, a system with a simple speed control system that obtains a torque command value signal from a comparison of a speed setting command and a speed feedback signal will not be able to smoothly respond to torque fluctuations caused by applying or releasing the braking device. Speed control was completely impossible.

[Means for solving problems and their effects]

The present invention has been developed with the above-mentioned points in mind, and in particular has a stop position holding function without impairing the high-precision speed control function, and can smoothly transition between the stop state and the speed control state. The purpose of the present invention is to provide an optimal motor stop control device that achieves the desired results.

Therefore, the present invention eliminates the need for a mechanical braking device for the electric motor, retains the torque command value at the time of stopping the electric motor, and transfers to stop control by adding a correction signal obtained by the position control system, and corrects the torque command value. This is a special device in which the signal can be separated and transferred to speed control.

〔Example〕

Next, the present invention will be explained in detail using an example using an AC non-commutator motor.

Here, the AC non-commutator motor is a combination of a cycloconverter power conversion section (hereinafter simply referred to as the power conversion section) and a brushless synchronous motor (hereinafter simply referred to as the motor).
Since this is commonly used as an 11t motor drive device having a four-quadrant control function of forward and reverse rotation drive and roundworm drive, a detailed explanation of the basic drive function will be omitted.

FIG. 1 and FIG. 2 are a control block diagram showing the main part configuration of an embodiment to which the present invention is applied, and a calculation 70 diagram in which the stop control function generation part is realized by a microconbeater.

In Fig. 1, 1 is a power converter, 2 is an electric motor, 3 is a two-phase pulse oscillator, and 4.5 is a frequency-voltage signal converter (FV
), 6, 9, 13, 15, 184'! Arithmetic unit, 7゜16
is an amplifier, 8 is a phase discrimination circuit, 10.11 is an integrator, 1
2 is a switch contact, 14 is a digital analog signal converter (DA), 17 is a current converter, and 19 is a current calculation regulator.

That is, the two-phase pulse oscillator 3 is provided at the end of the rotating shaft of the electric motor 2 and generates a signal with a frequency proportional to the rotation speed of the electric motor 2 using two pulse trains having a 90° phase difference. F
V4 gives a positive and negative DC voltage signal proportional to the input frequency by the positional relationship of the two-phase pulse oscillator 3 output leading by 90° or lagging by 90', and FV5 uses the speed setting signal 101 as input to generate a DC voltage proportional to the command frequency. give the signal. Therefore, the speed deviation is calculated by the calculator 6 and a speed deviation signal 102 is obtained. Note that the amplifier 7 is a DA which will be described later.
This is a proportional amplifier arranged for calculation by the arithmetic unit 15 in conjunction with the generation of the correction signal of the 14 outputs.

Further, the output signal of the two-phase pulse oscillator 3 is transmitted to the phase discrimination circuit 8.
If the rotation is in the forward direction, a subtraction pulse output is generated, and if the rotation is in the reverse direction, an addition pulse output is generated. Then, the command pulse of the speed setting signal 101 and the pulse output of the phase discrimination circuit 8 are added in the arithmetic unit 9, and the result is added to the integrator 10.
given to. Here, the integrator 10 may practically be a pulse counter, and the output signal 104 of such an integrator is integral correction information for speed calculation and acts as a torque command value. The integrator 11 is a double integrator that receives the output of the integrator 10 as an input, and functions to generate an output signal 105 as an integral correction for positional fluctuation during stop control.

The switch contact 12 maintains a closed circuit state only during stop control,
From this, the arithmetic unit 13 adds the integrator 11 output to the integrator 10 output. The output of the arithmetic unit 13 is DA
14 and is applied as a correction signal 106 to the arithmetic unit 15.

Furthermore, a correction signal 106 is added to the speed proportional calculation signal 103 in the calculation unit 15, and an optimum gain is applied by the amplifier 16 that obtains the calculation result to generate the torque command value signal 103.
7 is obtained. Then, the current of the power converter 1 is detected by the current converter 17, and the current and the torque command value signal 107 are calculated by the calculator 18. As a result of the calculation, the current calculation controller 1
A gate signal for the power converter 1 is generated by the minor loose control performed by 9, and a predetermined operation output is obtained.

In this manner, the integrator 10 plays the role of generating an offset for obtaining a torque command value during speed control, and functions as a torque command memory during stop control. Further, the integrator 11 functions as a correction signal generator that maintains the stop position only during stop control, and is disconnected by the switch contact 12 during speed control.

Of the connection configuration shown in Fig. 1, the analog circuit component of the stop control function generating section causes a drop in speed control accuracy due to drift, for example, but an example of digital calculation that can improve this is possible. is shown in FIG. 2. In FIG. 2, the frequency counter sample value 201,
When performing an integral calculation 210 from 202 and 203, integral coefficients 210 and 211 are obtained, and a position calculation proportional coefficient 221 is added to the result of the integral calculation as one flow.

In addition, as the other flow, after the position calculation integral coefficient 231 is multiplied 230, integral coefficients 241 and 242 are obtained when performing those integral calculations 240, and the integral calculation result is used as the contact point calculation 2 by the stop control command (not shown).
It is turned on and off by 50.

Furthermore, the results of the multiplication 220 and the contact calculation 250 are multiplied 260 by a digital analog output coefficient 261 to obtain an analog value 262 of the correction signal.

Therefore, by using such a microcomputer that can perform software processing, it is possible to dynamically adjust control parameters such as the integration time constant and realize a control system with higher precision.

〔Effect of the invention〕

As explained above, according to the present invention, there is provided a motor stop control device that is capable of smoothly transitioning from a stop position to speed control and stop control that can be moved from speed control to stop position holding control without interruption. Accordingly, it is possible to realize a useful electric motor drive device that enables high-quality and highly efficient production for drawing machines and other machines that perform similar control.

[Brief explanation of drawings]

FIGS. 1 and 2 are a control block diagram showing an embodiment of the present invention and a calculation flow diagram showing an example of a stop control function generating section thereof. 3... Two-phase pulse oscillator, 6, 9, 13, 15.
18... Arithmetic unit, 7, 16... Amplifier, 8... Phase discrimination circuit, 10.11...
・Integrator, 12...Switch contact, 101...
... Speed setting signal, 106 ... Correction signal, 1
07...Torque command value signal, 201, 202,
203... Frequency counter sample value, 210
, 240...Integral operation, 220, 230
, 260... Multiplication, 250... Contact calculation, 262... Analog value.

Claims (1)

[Claims] A two-phase pulse oscillator connected to a rotating shaft of an electric motor without a mechanical braking device, an addition/subtraction counter receiving an output signal and a speed setting command signal of a rotational direction detection circuit that obtains the output of the two-phase pulse oscillator, and the addition/subtraction. It includes a double integrator that receives a counter output as an input, a switch that sends a signal from the double integrator output only during stop control, and an adder that obtains the two outputs of the addition/subtraction counter and the switch, and a speed control output value. An electric motor stop control device, characterized in that the output of the adder is supplied as the other input to an arithmetic unit having one input thereof, and a torque command value signal is obtained based on the output of the arithmetic unit.