Vacon 100 flow, Руководство по применению, Страница: 228 / 386

The bit B7 controls the rotation direction of the injected high frequency signal, which is used
in the flying start of synchronous reluctance machines. Signal injection is used to detect the
frequency of the rotor. If the rotor is in a blind angle when the signal is injected, the rotor
frequency is undetectable. Reversing the rotation direction of the injection signal solves this
problem.
P3.1.4.8 FLYING START SCAN CURRENT (ID 1610)
Use this parameter to set the flying start scan current as a percentage of the motor nominal
current.
P3.1.4.9 START BOOST (ID 109)
Use this parameter with a process that has a high start torque because of friction.
You can use the start boost only when you start the drive. The start boost is deactivated after
10 seconds or when the output frequency of the drive is more than half of the frequency of
the field weakening point.
The voltage to the motor changes in relation to the necessary torque. This makes the motor
give more torque at the start and when the motor operates at low frequencies.
The start boost has an effect with a linear U/f curve. You can get the best result when you
have done the identification run and activated the programmable U/f curve.
10.2.5 I/F START FUNCTION
When you have a PM motor, use the I/f Start function to start the motor with constant current
control. You can receive the best effect with a high power motor. With a high power motor,
the resistance is low and it is not easy to change the U/f curve.
The I/f Start function can also give a sufficient torque for the motor at startup.
C
B
D
A
[s]
Fig. 40: The I/f start parameters
A. I/f Start Current
B. Output Frequency
C. Motor Current
D. I/f Start Frequency
VACON · 228 PARAMETER DESCRIPTIONS
10
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