3. Rolling mill control concepts

Notes on speed capture

1 – In the past, we used tachymetric dynamos, and the problem of accuracy was mainly due to temperature drift. With modern controllers, we measure speed by counting with a GI (pulse generator), which means that dynamics and precision are linked. If a GI has a limited number of tops per revolution, low-speed operation is tricky, as the count refresh time is too long: you can therefore have good precision, but with very low dynamics... In practice, GIs...