
2.EXPLANATION OF OPERATION MODES FANUC AC SPINDLE MOTOR αi series B-65280EN/05
- 68 -
2.2.10 Calculating the Position Gain for Orientation
(1) When the spindle orientation speed (parameter No. 4038) is set
to 0, the orientation speed is determined using the following
expression:
GEARRoriPG60Nori
where,
Nori : Orientation speed (motor speed) [min
-1
]
Rori : Motor speed limit ratio for orientation
(parameter No. 4076)
PG : Position gain on orientation [sec
-1
]
(parameter Nos. 4060 to 4063)
GEAR : Spindle-to-motor gear ratio
(parameter Nos. 4056 to 4059)
(2) The position gain for spindle orientation is obtained using the
following expression:
()
××+×π
≤
GEARRoriJlJm2
Tm
PG
where,
PG : Position gain for orientation [sec
-1
]
(parameter Nos. 4060 to 4063)
Tm : 30-min rated torque [Nm] for the motor when rotating
at Nori [min
-1
]
Jm : Rotor inertia [kgm
2
]
Jl : Load inertia converted to motor shaft inertia [kgm
2
]
Rori : Motor speed limit ratio for orientation
(parameter No. 4076)
GEAR : Spindle-to-motor gear ratio
(parameter Nos. 4056 to 4059)
(3) Calculation example when motor model α6i is being used alone
]Nm[8.47
1047.0][min1500
]W[7500
Tm
1
=
×
=
−
][kgm0179.0Jm
2
=
[%]33Rori
][sec9.35
33.00179.02
8.47
PG
1−
=
××π
≤∴