THE OPTIMAL CONTROL OF CHEMICAL PROCESSES
Abstract
Attention is focused on obtaining a near optimal controller, for chemical processes, which is simple to design and inexpensive to implement. Pontryagin's technique is used to show that for a quadratic objective function, and a process which is described by a set of ordinary differential equations, linear in the controllable variables, the optimal control is on-off control, when the controllable variables are assumed to be bounded. A technique of parameter optimization is developed and used to obtain the equations which specify the switching times. These equations are restricted to processes which can be approximated by stable, linear, sationary differential equations. For the special case of one switch it is shown that the control law can be transformed into a switching criterion which is linear in the process outputs. Employing this criterion continuously results in a feedback controller which requires only a relay and a summing device for implementation. Analog computer studies on the control of both underdamped and overdamped systems with the 'one switch into the future' optimal controller show that this controller gives a virtually dead beat type of response even for severe disturbances. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 03, 1962
- Accession Number
- AD0286160
Entities
People
- Coleman B. Brosilow
Organizations
- New York University Tandon School of Engineering