Parker AC30V Série Manuel Technique page 291

Pattern Generator
Parameters::Motor Control::Pattern Generator
The pattern generator function allows you to configure the Drive' PWM (Pulse Width Modulator) operation.
PNO Parameter Descriptions
0412
Stack Frequency
This parameter selects the PWM switching frequency of the output power stack.
The higher the switching frequency, the lower the level of motor audible noise. However, this is only achieved at the expense of
increased drive losses and reduced stack current rating.
Max value is Control Mode dependant :
12 kHz for PMAC SVC
14kHz for IM SVC
16 kHz for V/Hz
0413 Random Pattern IM
This parameter selects between random pattern (quiet motor noise) or the more conventional fixed carrier PWM strategies, for
induction motor only. When TRUE, random pattern is enabled. For Induction Motor Control, random pattern is only suitable for Stack
Frequency <=12kHz.Default value for induction motors is TRUE.
1268
Random Pattern PMAC
This parameter selects between random pattern (quiet motor noise) or the more conventional fixed carrier PWM strategies, for
PMAC motor only. When TRUE, random pattern is enabled. For PMAC SVC control random pattern is only suitable for Stack
Frequency <=8kHz. Default value for PMAC motors is FALSE.
0414
Deflux Delay
Sets the minimum allowed delay between disabling and then re-enabling PWM production (i.e. stopping and starting the drive).
Functional Description
The Drive provides a unique quiet pattern PWM strategy in order to reduce audible motor noise. The user is able to select between the quiet
pattern or the more conventional fixed carrier frequency method. With the quiet pattern strategy selected (RANDOM PATTERN enabled), audible
motor noise is reduced to a dull hiss.
In addition, the user is able to select the PWM carrier frequency. This is the main switching frequency of the power output stage of the Drive. A
high setting of carrier frequency (e.g. 6kHz) reduces audible motor noise but only at the expense of higher Drive losses and smooth motor
rotation at low output frequencies. A low setting of carrier frequency (e.g. 3kHz), reduces Drive losses but increases audible motor noise.
AC30V series Variable Speed Drive
D-65
Parameter Reference