Operating Instructions

Descriptions of Parameter Settings
Descriptions of Parameter Settings
194 | 443
Pr.
Explanation
Settings
Default
07-23
Automatic voltage regulation
(AVR) function
0: Enable AVR
1: Disable AVR
2: Disable AVR during deceleration
0
The rated voltage of a 220V motor is usually 200 V
AC
, 60 Hz / 50 Hz, and the input voltage of the AC motor drive
may vary from 180–264 V
AC
, 50 Hz / 60 Hz. Therefore, when the AC motor drive is used without the AVR function,
the output voltage is the same as the input voltage. When the motor runs at the voltage exceeding 12–20% of the
rated voltage, it causes higher temperatures, damaged insulation, and unstable torque output, which result in
losses due to shorter motor lifetime.
The AVR function automatically regulates the output voltage of the AC motor drive to the motor’s rated voltage
when the input voltage exceeds the motor’s rated voltage. For example, if the V/F curve is set at 200 V
AC
, 50 Hz
and the input voltage is at 200–264 V
AC
, then the drive automatically reduces the output voltage to the motor to a
maximum of 200 Vac, 50 Hz. If the input voltage is at 180–200 Vac, the output voltage to motor is in direct
proportion to the input voltage.
0: When the AVR function is enabled, the drive calculates the output voltage according to the actual DC bus
voltage. The output voltage does NOT change when the DC bus voltage changes.
1: When the AVR function is disabled, the drive calculates the output voltage according to the actual DC bus
voltage. The output voltage changes with the DC bus voltage, and may cause insufficient current, over-current or
oscillation.
2: The drive disables the AVR function only during deceleration to stop, and at this time, you can accelerate the
braking to achieve the same result.
When the motor ramps to stop, disable the AVR function to shorten the deceleration time. Then, use with the auto-
acceleration and auto-deceleration functions to make the motor’s deceleration more stable and quicker.
Pr.
Explanation
Settings
Default
07-24
Torque command filter time
(V/F and SVC control mode)
0.001 to 10.000 sec.
0.050
When the time constant setting is too large, the control is stable but the control response is slow. When the time
constant setting is too small, the control response is faster but the control may be unstable. For optimal setting,
adjust the setting based on the control stability or the control response.
Pr.
Explanation
Settings
Default
07-25
Slip compensation filter time
(V/F and SVC control mode)
0.001 to 10.000 sec.
0.100
Change the compensation response time with Pr.07-24 and Pr.07-25.
If you set Pr.07-24 and Pr.07-25 to 10 seconds, the compensation response time is the slowest; however, the
system may be unstable if you set the time too short.