ElmoMC SimplIQ Digital Servo Drives-Bell Command Reference - Manual (Page 290)

The following table lists the parameters of the algorithms referred to in this chapter.
Details are available in the
SimplIQ for Steppers Command Reference Manual.
Parameter Description
UM Unit mode. Determines the type of control algorithm used:
speed, dual position or open loop.
KP[N] N=2: Inner speed loop proportional gain
N=3: Outer loop gain (UM=4 and UM=5)
KI[N] N=2: Inner speed loop integral gain, I.
KV[N] Coefficients for high-order filter. The parameter KV[0] asserts if
these filters are used: If KV[0] is zero, the high order filter is not
used.
GS[N] Gain scheduling parameters.
MC Maximum drive phase current.
WS[28] Sampling time of the controller, in microseconds.
Table 8-2: List of All Control Parameters
Notation:
Standard mathematics notation is used here:
The time derivative is denoted by the letter s.
The expression sx is equivalent to dx/dt.
The expression x/s is equivalent to x dt
∫
, where t is the time and x(t) is any signal.
The operator z denotes a time advance of a single sampling time.
For a digital system with the sampling time of T
s
:
zx(kTx) = x[(k + 1) T
s
] or simply zx(k) = x(k+1).
8.1. Gain Scheduling
Gain scheduling is the process of on-line control algorithm switching, in order to
adapt the controller to varying circumstances.
SimplIQ enables manual or automatic gain scheduling, as set by GS[2].
GS[2] = 0: disables scheduling, the control gains is via KP[N] and KI[N].
GS[2] = 1..16: The controller gains are selected from the KG[N] vector. The selection is
manual, according to GS[2]. GS[2]=N selects the N controller out of the bank of 16
controllers. This option is good for scheduling due to load or posture events, that the
user program or the host may be aware of.
GS[2] = 64 sets speed-driven automatic gain scheduling, as explained in the following
section.
SimplIQ for Steppers Application Note The Position and Speed Controller
MAN-STECR (Ver. 1.1)
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