JPS5925586A - Automatic change-over device of inverter - Google Patents

Abstract

PURPOSE:To contrive to simplify the circuit of the titled device by a method wherein an approach run inverter is started, and after traverse operation is completed, operation is changed over an operation inverter. CONSTITUTION:When an operation command signal is inputted to a microcomputer 7 from an operation input part 8, frequency of the approach run inverter 4 is controlled to make a selected motor 2a-2c to start cushioningly up to a speed N, and frequency f1 corresponding to the speed N is made to be held. Then when the frequency signal f1 coincided with the traverse synchronization signal f0 of the operation inverter 1, traverse operation of the approach run inverter 4 is started. At traverse operation time thereof, when the frequency signal f1 of the approach run inverter 4 coincided with the traverse synchronization signal f0, operation is changed over from the approach run inverter 4 to the operation inverter 1. Accordingly, enhancement of precision of synchronization of the approach run inverter and the operation inverter can be attained by the simple circuit.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic inverter switching device when controlling the first few electric motors used in a spinning machine line or the like using run-up and running inverters.

As is well known, on the spinning machine line, there are many 1! 1. In these cities, uniform speed driving is practiced.

In recent years, motivators have been driven by inverters, and if the motive is controlled from the time of startup, the capacity of the inverter must be increased due to the inrush current of the machine. Therefore, in the evening, we used a run-up inverter to start the motive.
It has become common practice to switch over to the inverter for operation after a predetermined period of time to control the operation. Note that the above-mentioned run-up inverter is a device that starts the electric motor at a low frequency. After startup, this inverter increases the speed with a cushion, and when the period matches the operating inverter (frequency voltage and phase match) K, the motor operation control is switched from the run-up inverter to the operating inverter. 1° Traverse of the above spinning machine line The run-up inverter has also been used for some time. Here, traverse refers to winding the thread uniformly on a winding machine to improve the winding appearance. For this purpose, it is necessary to operate the run-up inverter that performs traverse by changing the operating frequency of the inverter in a pattern as shown in FIG.

On the other hand, since the operating frequency of the operating inverter is constantly changing, when switching the motor selected from the run-up inverter to the operating inverter, the inverter frequency changes from time to time according to a predetermined pattern, so
In such a situation, it is extremely difficult to perform homogeneous one-phase coincidence.

This invention was developed in view of the above circumstances, and it is designed to simplify the circuit and monitor the frequency of a single-car inverter, especially the frequency of the traverse synchronization signal.

An object of the present invention is to provide an automatic inverter switching device that can easily and accurately switch inverters on the condition that they match or consider that they are synchronized.

An embodiment of the present invention will be described below with reference to the drawings.
In FIG. 2, reference numeral 1 denotes an operating inverter, and this operating inverter 1 is composed of a converter section 1a, a capacitor 1b, and an inverter section 1c. 2 is a group of habits,
The electric currents 1, 2a, 2b, and 2c are connected to the operating inverter 1 through first contacts 3a, 3b, and 3c, which are sequentially controlled by the output of a sequence circuit to be described later. 4 is a run-up inverter, and this run-up inverter 4 is a converter fa.
4 a.

It is formed from a capacitor 4b and an inverter section 4C. , the output of this run-up inverter 4 is sequentially controlled by the output of a sequence circuit, which will be described later, through second contacts 5a, 5b,
Electric motors 2a, 2b via 5c'4.

2°6 connected to 2C is the first contact 3a13b, 3C15a1
This circuit 6 is a sequence circuit into which information for controlling 5b, 5c, etc. is input.
Signals are exchanged with the I/O board 7a. 1
An operation input signal is supplied from the abscess input section 8 to the boat 7a. Ryuki I/o boat 7a has ROM7c and RAM7d by bus 7b.

It is directly connected to the interrupt control circuit 7e and the CPU 7f. The output of the microcomputer 7 generates a signal for controlling the inverter section 4c of the inverter 4 in a PWM control control signal generating section 90 and a frequency setting control signal generating section 9. The drive circuit 0 is applied to the control elements constituting the inverter section 4c. 11 is the inverter section 1c of the operating inverter 1
"< A p w M control signal generating section that generates a control signal, and the signal generated by this generating section 11 is transmitted to the drive circuit 1.
Inverter section via 2 parts]. The signal is given to the control elements constituting the CY.

Reference numeral 13 denotes an AND circuit forming a coincidence circuit, and a first input terminal of this AND circuit 13 is supplied with a traverse synchronization signal from a terminal 11a of the PWM control signal generator 1. Further, an output signal (INTE) from the interrupt control circuit 7e is supplied to the second input terminal of the AND circuit 13. The AND circuit 13 sends out an output signal when the AND condition of the signal is satisfied, and this signal is supplied to the CPU 7r as an interrupt request signal. The AND circuit 13 uses the traverse signal fo of the running inverter 1 and the run-up inverter 4 based on the interrupt control signal output from the microcomputer 7.
0 frequency f1 is detected.

Next, the operation of the above embodiment will be described with reference to FIGS. 3A-KY, assuming that the running inverter 1 is already in operation before the run-up inverter 4 is operated. Here, the functions of the sequence circuit 6 and the microcomputer 7 will be described. Sequence episode! I86 sequentially selects two motor groups, and after the run-up inverter 4 completes traverse operation, the selected motor is switched from the run-up impark 4 to the drive inverter 1 on the condition that the frequencies of the run-up inverter and the drive inverter 1 match.
1, which performs a predetermined switching, t.

The microcomputer 7 has the following functions. That is, on the condition that a motor is selected in the sequence circuit 6, a start means for cushion-starting the selected motor to a predetermined speed N and holding m[N for a predetermined time, and a frequency signal f1 corresponding to the speed NK are provided. hold, and on the condition that the traverse synchronization signal fo of the operating inverter 1 taken in from the operation control signal generating section and the frequency signal f1 match, the run-up inverter 4 is caused to perform traverse operation based on a predetermined pattern. A synchronization match is determined on the condition that the traverse synchronization signal fO of the traverse driving means controlling the inverter 1 and the frequency signal f1 of the run-up inverter 4 match, and the synchronization match is determined. It is comprised of means for sending a signal to the sequence circuit 6 and outputting a low speed command to the run-up control signal generating section 9 under the condition that the run-up inverter 4 is switched to the running inverter 1 by the circuit.

FIG. 3A is a characteristic diagram showing the operating pattern of the run-up inverter. When the operation command signal b (Fig. 3B
) is input from the operation input section 8 to the microcomputer 7. This combined signal is P from the microcomputer 7.
WM control control signal section 9 power is reduced. The PWM control control signal generating section 9 has a wave number setting input and a voltage setting input, and an output signal obtained by a signal from the computer 7 is supplied to both input terminals and is supplied to the drive circuit 10. That is, the run-up inverter 4 is started by the operation command signal shown in FIG. 3B. After starting, time t shown in FIG. 3C
At step 1, a low speed command signal C) is sent out from the sequence circuit 6. Along with this signal c1, a low-speed relay contact signal d shown in the third diagram is sent out from the sequence circuit 6. When this signal d is sent out, the contact 5a shown in FIG. 2 is closed, and the electric motor 2a is started. After the direct drive motor 2a is started, the motor 2a waits for the inrush current to decrease and maintains a low speed state until the high speed command signal arrives. Figure 3E
is the operating waveform of the direct drive motor 2a. Here, the high speed command signal f
arrives from the sequence circuit 6 at time t2 (FIG. 3F), the operating frequency of the run-up inverter 4 increases,
The speed of the electric motor 2a increases and decreases from time t2 to t3.

The operating frequency of the run-up inverter 4 is held at time J, and the increase in frequency is stopped.

On the other hand, at time t3, an interrupt enable signal (IIIJTE) is sent from the microcomputer 70 interrupt control circuit 7e.
) is sent out as shown in Figure 3G. Time ↑, 4
When this happens, the operating inverter 1 toranosu signal becomes P.
The signal is input to the AND circuit 13 from the WM control control signal generating section. Since the enable signal (NTE) shown in FIG. 3G is input to this AND circuit 13, the AND circuit 1
3, the first interrupt request signal (I
NTR) is sent out.

This signal (INTR) causes an interrupt to be applied to the CPU 7f of the microcomputer 7. As a result of this action, the traverse operation of the run-up inverter 4 is started, and the traverse operation is continued until the t1-th synchronization signal arrives. Since the operating frequency of the run-up inverter 4 during this traverse operation changes as shown in FIG. 1, the operating frequency from time t4 to time t5 is as shown in FIG. 3. As the run-up inverter 4 performs the traverse operation, it follows the operating frequency of the operation inverter (-1).Here, the second interrupt request signal (INTR2) (Fig. 3) is sent to the CPU 7f. If the operating frequency of the run-up inverter 4 is the hold frequency, it is assumed that the frequency tracking of the operating inverter 1-\ has been completed, and the synchronization completion signal (Fig. 3) is activated at time t6. circuit 6
Send it out. After this completion signal is sent out, the operation is switched from the run-up inverter 4 to the running inverter l.
The α-motor 2a is thereafter controlled by the output of the operating inverter 1. When the operation switching is completed, a frequency lowering command signal shown in FIG. 3K is sent to the run-up inverter 4 at time t7. Time t8 becomes the starting low-speed frequency set value for the next direct-drive motor. In addition, FIG. 4 is a pattern characteristic diagram showing the traverse operation frequency changes of the run-up inverter 4 and the running inverter 1 operated according to the above-mentioned FIGS. 3A to 3A. In FIG. This corresponds to the action at time t5**A, t5 in FIG. That is, +rh+ is the hold frequency, fh2 is the time when traverse operation starts, and fh= is the time when frequency tracking is completed when the traverse synchronization signal matches.As described above, according to the present invention, when the run-up inverter is started, Since the inverter is switched to the operating inverter after the traverse operation is completed, the accuracy of synchronization of both inverters can be improved with a simple circuit.

[Brief explanation of drawings]

Fig. 1 is an operating frequency pattern characteristic diagram of the inverter during traverse operation, Fig. 2 is a configuration explanatory diagram showing an embodiment of the present invention, Fig. 3 A to K are time charts of the approach inverter, and Fig. 4 is during operation. This is a diagram showing the operating frequency pattern characteristics of the inverter and the run-up inverter. 1... Operating inverter, 2... Electric motor group, 4...
Run-up inverter, 6... Sequence circuit, 7... Microcomputer, 9.11... PWM control'i[
1 signal generator, 13...AND circuit.

Claims (1)

[Claims] (11) An operation inverter that operates the electric motors of multiple mills at uniform speed, a run-up inverter that supplies output to each of the motors from the time of startup to the completion of traverse operation, and an operation that sends signals to drive and control the drive and run-up inverters. and the run-up control signal generating unit, and the drive and drive motors are started, and the above '' selects the motors in sequence, and after the run-up inverter completes traverse operation of the selected electric motor, the frequencies of the run-up inverter and the driving inverter match. A sequence circuit that performs a predetermined switching L'1 from the run-up inverter to the running inverter under the condition of , and a cushion start of the selected motor to a predetermined speed N and a predetermined speed T on the condition that the motor is selected in this sequence circuit. A start means for holding time, a frequency signal f1 corresponding to the speed N, and a traverse synchronization signal f of the operating inverter taken in from the operation control signal generating section.
and a traverse operation means for causing the approach inverter to perform traverse operation based on a predetermined pattern and controlling the operation inverter to follow, and the traverse synchronization signal f of the operation inverter during this traverse operation.
o and the run-up inverter frequency signal f1 match, it is determined that they match, and a synchronization match signal '￥ Ail
a microcomputer comprising means for outputting a low speed finger to the run-up control signal generating section on the condition that the run-up inverter is switched to the running inverter in the sequence circuit; and an output from the microcomputer. An inverter automatic switching device characterized by comprising a coincidence circuit that detects coincidence between the traverse signal fO of the running inverter and the frequency signal of the run-up inverter based on the interrupt control signal.