Mitsubishi FR-A740-00023-EC, Инструкция по эксплуатации

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86
Control mode
(1) Speed control
Speed control operation is performed to zero the difference between the speed command (
ω
*) and actual rotation
detection value (
ω
FB). At this time, the motor load is found and its result is transferred to the torque current
controller as a torque current command (iq*).
(2) Torque current control
A voltage (Vq) is calculated to start a current (iq*) which is identical to the torque current command (iq) found by
the speed controller.
(3) Magnetic flux control
The magnetic flux (
φ
2) of the motor is derived from the excitation current (id). The excitation current command (id*)
is calculated to use that motor magnetic flux (
φ
2) as a predetermined magnetic flux.
(4) Excitation current control
A voltage (Vd) is calculated to start a current (id) which is identical to the excitation current command (id*) found by
magnetic flux control.
(5) Output frequency calculation
Motor slip (
ω
s) is calculated on the basis of the torque current value (iq) and magnetic flux (
φ
2). The output
frequency (w0) is found by adding that slip (
ω
s) to the feedback (
ω
FB) found by a feedback from the encoder.
The above results are used to make PWM modulation and run the motor.