Delta MH300 Series

Chapter 12 Description of Parameter Settings
MH300
12.1-10-8

10-31
I/F Mode, Current Command
Default: 40
Settings 0–150% rated current of the motor
 Sets the current command for the drive in the low speed area (low speed area: Frequency
command < Pr.10-39). When the motor stalls on heavy duty start-up or forward/reverse with
load, increase the parameter value. If the inrush current is too high and causes oc stall, then
decrease the parameter value.

10-32
PM FOC Sensorless Speed Estimator Bandwidth
Default: 5.00
Settings 0.00–600.0 Hz
 Sets the speed estimator bandwidth. Adjust the parameter to change the stability and the accuracy
of the motor speed.
 If there is low frequency vibration (the waveform is similar to sine wave) during the process, then
increase the bandwidth. If there is high frequency vibration (the waveform shows extreme
vibration and is like a spur), then decrease the bandwidth.

10-34
PM Sensorless Speed Estimator Low-pass Filter Gain
Default: 1.00
Settings 0.00–655.35
 Changes the response speed of the speed estimator.
 If there is low frequency vibration (the waveform is similar to a sine wave) during the process,
then increase the gain. If there is high frequency vibration (the waveform shows extreme
vibration and is like a spur), then decrease the gain.

10-35
ARM (Kp)
Default: 1.00
Settings 0.00–3.00

10-36
ARM (Ki)
Default: 0.20
Settings 0.00–3.00

10-39
Frequency Point to Switch from I/F Mode to PM Sensorless Mode
Default: 20.00
Settings 0.00–599.00 Hz
 Sets the frequency for the switch point from low frequency to high frequency.
 Due to the weak back-EMF in the low frequency area, PM sensorless mode cannot estimate the
accurate speed and position of the rotor. Thus, using I/F mode control is more suitable. In the
medium-to-high frequency area, PM sensorless can accurately estimate the back-EMF, stabilizes
and control the motor with lower current.
 If the switch point is too low and PM sensorless mode operates at a too low frequency, the motor
does not generate enough back-EMF to let the speed estimator measure the rotor right position
and speed, and causes stall and oc when running at the switch point frequency.