Parker AC890 Product Manual page 451

PHASE ADVANCE
This selection implements a transfer function of the type 1 + s / 2*pi*f1 , which gives a phase
advance between the frequencies f1 to f2. When this function is selected, the values of f1 and f2 are set by the parameters
COMPENSATION F1 and COMPENSATION F2.
NOTCH FILTER
This selection will give a zero transmission notch at a frequency specified by parameter COMPENSATION F1. It has a
phase delay of 1 sample period. A sample period is 1/(2 * switching frequency). For example, if the switching frequency is
4kHz, a sample period is 125us.
Summary
"COMPENSATN
TYPE" Selection
NONE
MAX ATTENTUATION
MINIMUM PHASE
PHASE ADVANCE
NOTCH FILTER
D-160
Page
Compensation Type
Torque demand is transmitted
unchanged.
First order filter with zero
transmission at Nyquist limit.
First order recursive filter with
minimum phase shift.
Phase advance function.
Zero transmission notch at
selected frequency.
1 + s / 2*pi*f2
Action of
"COMPENSATION F1"
-
sets 3db cutoff frequency
sets 3db cutoff frequency
Sets value of f1 (beginning
of phase advance).
Sets frequency of zero
transmission notch.
Action of
COMPENSATION F2"
-
has no effect
has no effect
Sets value of f2 (end of phase
advance).
has no effect
890SD Standalone Drive - Frames G, H & J