In primary control system, we were told that the ideal compersation curve for a open loop system is a three stage frequency compensation illustrated as follow: | ; | ; (40db/dc | ; | \\ | \\ (20db/dc |---------------\\------------- | \\ | \\ | ; | ;(40db/dc ;
at low frequency section,slope is 40db, middle frequency is 20db and cross x-axis, at high frequency will be 40db else. as we all know, that at the low frequency section,slope is 40db/dc and phrase magin is zero and its amplication is greater than 1 is it oscillation at the section?