Controller Design for Integrating Processes in SISO or MIMO Systems

Abstract

A two-step design to control integrator processes in an SISO or MIMO system is proposed. For an SISO system, the first step of the design is to stabilize the integrator process with P&D modes in a secondary loop to achieve good stability robustness and modest performance. In the second step of design, a P&I controller in the primary loop is derived to improve the overall performance. By this way, an equivalent two-element control system comprising of a single PID control loop and a pre-filter applying on the set-point command is derived. The same design approach is then applied to design multiloop SISO controllers for MIMO processes, where integrating behavior exists. By employing the same two-step design and the direct method of Huang et al. (2003), 2-df multi-loop PI/PID controllers can be obtained. The Simulation results show that this presented method is effective for both SISO and MIMO process with integrators.