5.4 Details of Function Codes
5-116
Vector control with speed sensor
This control requires an optional PG (pulse generator) and an optional PG interface card to be mounted on a
motor shaft and an inverter, respectively. The inverter detects the motor's rotational position and speed
according to PG feedback signals and uses them for speed control. It also decomposes the motor drive
current into the exciting and torque current components, and controls each of components in vector.
It is possible to obtain the desired response by adjusting the control constants (PI constants) using the speed
regulator (PI controller).
The control enables speed control with higher accuracy and quicker response than vector control without
speed sensor.
(A recommended motor for the control is a Fuji VG motor exclusively designed for vector control.)
Since slip compensation, dynamic torque vector control, and vector control with/without speed
sensor use motor parameters, the following conditions should be satisfied to obtain full control
performance. Otherwise, adequate control performance may not be achieved.
y A single motor is controlled per inverter.
y Motor parameters P02, P03, P06 to P23, P55 and P56 are properly configured. Or,
auto-tuning (P04) is performed. (Using a Fuji VG motor under vector control with speed sensor
requires just selecting a Fuji VG motor with function code (P99 = 2) and does not require
auto-tuning.)
y Under dynamic torque vector control, the capacity of the motor to be controlled is two or more
ranks lower than that of the inverter; under vector control with/without speed sensor, it is the
same as that of the inverter. Otherwise, the inverter may not control the motor due to decrease
of the current detection resolution.
y The wiring distance between the inverter and motor is 50 m or less. If it is longer, the inverter
may not control the motor due to leakage current flowing through stray capacitance to the
ground or between wires. Especially, small capacity inverters whose rated current is also small
may be unable to control the motor correctly even if the wiring is less than 50 m. In that case,
make the wiring length as short as possible or use a wire with small stray capacitance (e.g.,
loosely-bundled cable) to minimize the stray capacitance.
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