Increasing The Motor Output Torque Further In Low Speed Range - Toshiba Tosvert VF-AS1 Instruction Manual

6.23

Increasing the motor output torque further in low speed range

 : Exciting strengthening coefficient
 : Stall prevention factor
The output torque of the motor can adjusted using the parameters described in 6.22 in most cases, but if a finer
adjustment is required, use these parameters.
[Parameter setting]
Title
 Exciting strengthening coefficient
 Stall prevention factor
If the torque needs to be increased in low speed range (10Hz or less as a guide)
Perform auto-tuning according to the instructions in 6.22, and if the torque needs to be increased further in low
speed range, first increase the slip frequency gain () to a degree (80% or so as a guide) that hunting of the
motor does not occur. Then, increase motor constant 1 () by 1.1 times the current value as a guide. If the
torque needs to be increased even further, increase the exciting current factor () to a maximum of 130%.
 is a parameter that increases the magnetic flux of the motor at low speeds, so specifying a higher value for
 increases the no-load current. If the no-load current exceeds the rated current, do not adjust this
parameter.
If the motor stalls when operated at frequencies above the base frequency
Adjust  (stall prevention factor).
If a heavy load is applied momentarily (transiently), the motor may stall before the load current reaches the stall
6
prevention level (). In such a case, a motor stall may be avoided by reducing the value of 
gradually.
Function
~ %
~
F-42
Adjustment range
E6581442
Default setting

