Elmomc SimplIQ Digital Servo Drives-Bell Getting Started Manual de usuario descargar pdf (Pagina 94)

The SimplIQ for Steppers Getting Started & Tuning and Commissioning Guide

MAN-BELGS (Ver. 1.1)

For speed control, the derivative term represents acceleration. Acceleration is

hard to estimate with acceptable noise, so that the inclusion of the D term in

speed controllers is impractical. We therefore use the PI (PID without the D) form

for speed controllers. To summarize, for PI controllers we use

+=)(

(20)

that is

() ()

()

() ()

()

ttKdK)t(u

θ−θ⋅+ττθ−τθ⋅=

∫

∞−

&&&&

(21)

and for PID controllers we use (19).

B.4.3.2 The High Order Filter

The PI/PID controllers by themselves are fine for many applications, but they

have the following limitations:

 They cannot notch out resonance.

 They have poor high frequency measurement noise attenuation.

 They have limited ability to add extra phase compensation, as required by

plants with a large mismatch between the inertias of the motor and the load.

The SimplIQ controller structure includes, in addition to the PI/PID controller, a

freely parameterized high-order (up to 8th order) linear filter to overcome the

PI/PID limitations. The resulting structure is:

KP[2]+KI[2]/s P(s)

Position

Speed

KP[3]

Ref

High

order

filter

1 2 ... 89 90 91 92 93 94

Sin comentarios

Elmomc SimplIQ Digital Servo Drives-Bell Getting Started Manual de usuario Pagina 94