Mitsubishi Electric FR-A800, Instruction Manual

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Specification comparison between PM sensorless vector control and induction motor control Appendix
A - 4
A.2 Specification comparison between PM sensorless vector
control and induction motor control
For the motor capacity, the rated motor current should be equal to or less than the rated inverter
current. (It must be 0.4 kW or higher.)
If a motor with substantially low rated current compared with the rated inverter current is used,
speed and torque accuracies may deteriorate due to torque ripples, etc. Set the rated motor current
to about 40% or higher of the rated inverter current.
Item PM sensorless vector control (MM-CF) Induction motor control
Applicable motor
앫
IPM motor MM-CF series (0.5 to 7.0 kW)
(Refer to page 8-8.)
앫
IPM motors other than MM-CF (tuning required)
Induction motor
Starting torque
High frequency
superposition control
200% (200% for the 1.5 kW or
lower with MM-CF, 150% for
the 2.0 kW or higher)
200% (FR-A820-00250(3.7K) or lower
and FR-A840-00126(3.7K) or lower)
150% (5.5K or higher)
under Real sensorless vector control
and vector control
Current synchronization
operation
50%
Zero speed
High frequency
superposition control
Available
(Select the HD rating for
zero-speed 200%.)
Available under Real sensorless
vector control and vector control
Current synchronization
operation
Not available
Carrier frequency
High frequency
superposition control
6 kHz (Pr. 72 = "0 to 9 "),
10 kHz (Pr. 72 = "10 to 13"),
14 kHz (Pr. 72 = "14 or 15")
(6 kHz in a low-speed range
of 10 kHz or higher.
2 kHz is not selectable.)
앫
Any value in the range of
0.75 kHz to 14.5 kHz
(FR-A820-03160(55K) or lower
and FR-A840-01800(55K) or
lower)
앫
0.75 kHz to 6 kHz
(FR-A820-03800(75K) or higher
and FR-A840-02160(75K) or
higher)
Current synchronization
operation
2 kHz (Pr. 72 = "0 to 5"),
6 kHz (Pr. 72 = "6 to 9"),
10 kHz (Pr. 72 = "10 to 13"),
14 kHz (Pr. 72 = "14 or 15")
(6 kHz in a low-speed range
of 10 kHz or higher.)
Automatic restart
after instantaneous
power failure
No startup waiting time.
Using the regeneration avoidance function or retry function
together is recommended.
Startup waiting time exists.
Startup delay
Startup delay of about 0.1 s for magnetic pole position
detection. No startup delay (when online auto
tuning is not performed at startup).
Driving by the
commercial power
supply
Cannot be driven by the commercial power supply.
Can be driven by the commercial
power supply. (Other than vector
control dedicated motor.)
Operation during
coasting While the motor is coasting, potential is generated across
motor terminals.
While the motor is coasting, potential
is not generated across motor
terminals.
Torque control Not available
Available under Real sensorless
vector control and vector control.
Position control
High frequency
superposition control
Available (sensorless)
Available under vector control.
Current synchronization
operation
Not available
Tab. A-2: Differences between PM sensorless vector control and induction motor control
NOTES Before wiring, make sure that the motor is stopped. Otherwise you may get an electric shock.
Never connect an IPM motor to the commercial power supply.
No slippage occurs with an IPM motor because of its characteristic. If an IPM motor, which took
over an induction motor, is driven at the same speed as for the general-purpose motor, the run-
ning speed of the IPM motor becomes faster by the amount of the general-purpose motor's slip-
page. Adjust the speed command to run the IPM motor at the same speed as the induction motor,
as required.