YASKAWA VU*B****AA*-134 Series Manual page 15

Torque Compensation
High speed motors typically have very low impedance compared to standard 60/120 Hz
motors. These high speed/low impedance motors saturate easily and may cause hunting and
oscillation when a high V/f pattern is applied, especially at high frequencies. Therefore,
Torque Compensation Gain (C4-01) is modified to limit voltage boost above 120 Hz and
eliminate voltage boost above 160 Hz as shown in
Figure 2
On-Delay Compensation
High speed motors typically operate at low V/f ratios compared to standard 60/120 Hz
motors, and On-Delay Compensation settings may adversely affect the motor voltage and
cause hunting and oscillation. Therefore, On-Delay Compensation Gain is modified to
reduce its effectiveness above 120 Hz as shown in
Note: When S1-01 = 0, On-Delay Compensation is disabled at all frequencies.
Figure 3
YASKAWA ELECTRIC TM.V1000SW.134A 1000 Hz High Frequency Custom Software Supplement
5 New and Modified Software Functions
C4-01
0
120 Hz
Figure 2 Torque Compensation Gain
1.00
0
120 Hz
Figure 3 On-Delay Compensation Gain
Figure 2.
Output
Frequency
160 Hz
(Fout)
Figure 3.
Output
Frequency
160 Hz
(Fout)
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