PID Controller Design for Solar Tracker via Modified Ziegler Nichols Rules

In this paper, Ziegler Nichols tuning rules for the tuning of proportional integral derivative (PID) controller (ZN-PID) are modified via shift in the critical point of the plant to satisfy the criterion for the desired phase margin of the system. The given approach entails the use of a direct formula for the formulation of modified ZN-PID controller, which obviates the need for the use of highly randomized soft computing algorithms, complex nonlinear control strategies and time consuming iterative approaches of controller design. The capability of the modified Ziegler Nichols rules is demonstrated via investigation of the transient and disturbance rejection performance of the solar tracking system. A wide comparison in terms of simulation results and computation of error indices with multifarious existing techniques is performed to demonstrate the superiority of the ZN-PID technique.