JP2606447Y2 - Speed limiter in torque control of newspaper rotary press - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a newspaper rotary press, and more particularly to a speed limiter for an induction motor.

[0002]

2. Description of the Related Art FIG. 3 is a system configuration diagram showing an example of a conventional system, wherein 1 is a master controller, 2 is an inverter controller,
3 is a three-phase induction motor, 4 is a spindle rotation detector, 5 is a spindle,
6 is a clutch, 7 is a relay contact linked to the clutch 6,
8 is a printing speed setting device, 9 is a (frequency / voltage) converter, 10
Denotes an adder / subtractor, and 11 denotes a PI calculator. In FIG. 3, first, a frequency signal from the spindle rotation detector 4 is converted to an analog voltage signal by a (frequency / voltage) converter 9, and this is used as a printing speed feedback signal, and the printing speed setting device 8 is used.
Is calculated by the adder / subtractor 10, the deviation is further calculated by the PI calculator 11, and the result is used as a torque command signal to each inverter control device 2.
Then, the induction motor 3 is controlled so as to generate a torque according to the torque command given to each inverter control device 2.

[0003]

However, in the prior art, on the condition that the main shaft is connected by a clutch,
Since the torque command is given to each inverter, if the inverter is operated in a state where the clutch is disengaged, the induction motor will be in a no-load operation state, and there is a possibility that the induction motor will run away to the maximum rotation speed. SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and a purpose thereof is to limit the rotation speed of an induction motor, thereby preventing a runaway of a machine. Is provided.

[0004]

Means for achieving the object are to provide a print speed command set by a print speed setting device in the master control device to each inverter control device, and to provide the inverter control device with a print speed command. A rotation speed limiting circuit is provided, and the rotation speed limiting circuit includes a motor rotation speed estimation unit, a comparison speed setting unit, and a speed comparison unit.

[0005]

The operation is as follows. The speed estimation unit calculates the rotation speed of the induction motor from various electric constant voltage vectors and current vectors of the induction motor, and the comparison speed setting unit calculates the offset value to the rotation speed signal given by the master limiting device. Is added to obtain a variable overspeed detection value, and the speed comparison unit compares the rotation speed with the variable overspeed detection value, and stops the inverter when the rotation speed exceeds the detection value. Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

[0006]

FIG. 1 is a system configuration diagram showing one embodiment of the present invention, and FIG. 2 is a rotation speed limiting circuit diagram. In FIG. . FIG.
In the present invention, the main point of the present invention is that the printing speed command n set by the printing speed setting device 8 in the master control device 1 is given to each inverter control device 2 and the rotation speed shown in FIG. That is, the limiting circuit 12 is provided.

In a rotation speed limiting circuit 12 shown in FIG. 2, an adder / subtractor 10 adds an offset value 14 provided for a rotation speed limiter to a printing speed command n given by a master controller 1 by a comparison speed setting unit 13. And a variable overspeed detection value, and a speed estimation unit 15 controls various electric constants, a voltage vector v, a current vector i of the induction motor 3 incorporated in the rotation speed limiting circuit 12 and a torque command signal from the PI calculator 11. The rotation speed n 'of the induction motor 3 is calculated from τ by the motor rotation speed estimation unit 15, and the speed comparison unit 16 compares the variable overspeed detection value with the rotation speed n'.
Is operated to stop the inverter control device 2 when exceeds the variable speed detection value.

[0008]

As described above, according to the present invention, in the torque control of the induction motor, the rotation speed can be limited even when the induction motor is in a no-load state. Runaway can be prevented.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram showing an embodiment of the present invention.

FIG. 2 is a rotation speed limiting circuit diagram showing one embodiment of the present invention.

FIG. 3 is a system configuration diagram showing an example of the related art.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 master control device 2 inverter control device 3 three-phase induction motor 4 main shaft rotation detector 5 main shaft 6 clutch 7 relay contact 8 printing speed setting device 9 (frequency / voltage) converter 10 adder / subtractor 11 PI calculator 12 rotation speed limiting circuit 13 Comparison speed setting section 14 Offset value 15 Motor rotation speed estimation section 16 Speed comparison section

Claims (1)

(57) [Scope of request for utility model registration] 1. A plurality of three-phase induction motors are arranged in series,
For each section of the drive shaft of each electric motor separated by the main shaft and the clutch, a newspaper rotary press that obtains power from the main shaft of the section is provided, and further, a main shaft rotation detector is provided only at one main shaft of the reference section, The section where the clutch is disengaged is a newspaper rotary press that cannot detect the rotation speed.It calculates the signal from the print speed setting device and the print speed feedback signal, and uses the result as a torque command signal to control multiple three-phase induction motors. In the sensorless vector torque control device of a newspaper rotary press applied to the corresponding inverter control device for driving, in addition to the torque command signal, various electric constants of the induction motor rotated by the torque command signal, a voltage vector, The actual speed calculated from the current vector is compared with the set speed set by the printing speed setting device. The speed comparing section provided, so that the output of the speed comparison unit is an induction motor does not exceed the set speed of,
A speed limiting device in torque control of a newspaper rotary press, wherein a comparative speed setting unit for adding an offset value to the setting signal is provided, and the speed is limited by the comparative speed setting unit.