Toshiba 1550, Руководство по обслуживанию

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1550/1560 DRIVE 6 - 10 Mar. 1998 © TOSHIBA
6.4 Main Motor
6.4.1 Main motor drive
+
(F-MTR-REF)
PLL-OK
MAIN-CW/CCW
MTR-BRK
MAINMTR-ON
+24V
LGC
Difference
Speed
comparison
Rotation
control
Difference
Voltage
detection
circuit
Excitation
phase
switching
section
Rotor
position
detection
Lock
protection
circuit
Crystal
oscillator
Wave
rectification
Phase
comparison
Hall element C
Hall
element B
Hall element A
FG pulse
Phase W
Phase V
Phase U
Reference frequency
Main motor (M1)
678
Control
signal
(1) LGC outputs a control signal for main motor rotation. (MAIN-CW/CCW: Rotation direction, MAIN-
MTR-ON: Motor rotation command)
(2) The excitation phase switching section excites each phase of the main motor
→
main motor rotates.
(3) Hall elements A-C detects rotation position of motor (rotor).
(4) The excitation phase switching section switches the excitation of each phase.
(By repeating (2) through (4), the motor continues to turn.)
(5) An FG pulse is generated by FG pattern attached to the main motor.
(6) The FG pulse and the reference frequency are compared for their phase and speed, and their
differences added to IC3.
(7) Change the switch timing of the excitation phase switching section, according to the signal obtained
at (6) above.
= Control so that the FG pulse and reference frequency are equal
→
main motor rotates at a fixed
speed (lock-range condition).
(8) As the main motor goes into the lock-range condition, the excitation phase switching section out-
puts a PLL-OK signal to LGC (“L” level).
(9) When MTR-BRK from LGC goes to “L” level, the brake is applied to rotation of the main motor, and
when the MAIN MTR-ON signal becomes “L” level, the main motor stops.