Emerson Exchange 365

If there were no unmeasured disturbances, feedback control would not be necessary. Process engineers and operators could home in on the best PID output and just leave it at this value. In fact many process engineers are much more comfortable with setting a stream flow per a process flow diagram than relinquishing to a PID controller that they don’t quite understand. In batch operations, often flows are sequenced based process design knowledge rather than released to a PID loop for fed-batch control. Also algorithms could be designed to focus on providing the best setpoint response and compensating for known disturbances. Read the full text.