What are integrating processes and how do they affect control?

Integrating (non-self-regulating) processes have no inherent steady state - output continues changing as long as input is non-zero. Example: level in tank with flow in/out - level keeps rising/falling if flows differ. Transfer function has 1/s term: Y(s)/U(s) = K/(s). Control implications: cannot use integral-only control (unstable), proportional control gives offset but stable, P+I works but must be carefully tuned, and process can drift indefinitely without control. Tuning: longer integral time than similar self-regulating process, moderate proportional gain.