Control Mode - Mitsubishi Electric FR-A700 Instruction Manual

Parameter
6.2

Control mode

V/f control (initial setting), advanced magnetic flux vector control, real sensorless vector control
and vector control are available with this inverter.
V/f control
It controls frequency and voltage so that the ratio of frequency (f) to voltage (V) is constant when
changing frequency.
Advanced magnetic flux vector control
This control devides the inverter output current into an excitation current and a torque current by
vector calculation and makes voltage compensation to flow a motor current which meets the
load torque.
Real sensorless vector control
By estimating the motor speed, speed control and torque control with more advanced current
control function are enabled. When high accuracy and fast response is necessary, select the
real sensorless vector control and perform offline auto tuning and online auto tuning. This con-
trol can be applied to the following applications:
– To minimize the speed fluctuation even at at a severe load fluctuation
– To generate low speed torque
– To prevent machine from damage due to too large torque (torque limit)
– To perform torque control
Vector control
When the FR-A7AP is mounterd, full-scale vector control operation can be performed using a
motor with encoder. Fast response/high accuracy speed control (zero speed control, servo
lock), torque control, and position control can be performed.
● What is vector control?
Excellent control characteristics when compared to V/f control and other control techniques,
achieving the control characteristics equal to those of DC machines. It is suitable for
applications below.
– To minimize the speed fluctuation even at at a severe load fluctuation
– To generate low speed torque
– To prevent machine from damage due to too large torque (torque limit)
– To perform torque control or position control
– Servo-lock torque control which generates a torque at zero speed (i.e. status of motor
shaft = stopped)
FR-A700 EC
Control mode
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