PID Controller Design using Characteristic Ratio Assignment Method for Coupled-Tank Process

Characteristic ratio assignment in fractional order systems

“…Almost all existing CRA methods are designed for integer order transfer functions. Some practical applications of CRA based control design methods have been reported in the literature [23,24].…”

“…Another approach is to employ the characteristic ratio assignment (CRA) method [19][20][21][22][23][24] in which at first an all-pole system is designed to obtain a non-overshooting step response. Then, by adjusting the time constant, the speed of the response is adjusted properly.…”

Non-overshooting PD and PID controllers design

“…In [20], a fuzzy PID controller to achieve a zero overshoot step response has been presented. The CRA and CDM approaches have been employed to design non-overshooting PID controllers for some real plants [21][22][23]. In [24], a modified version of the PID controller, called I+PD controller, has been designed using process step response and damping optimum criterion.…”

PI Controller Design for a Coupled Tank System Using LMI Approach: An Experimental Study

“…However, this Ziegler-Nichols based tuning method fails to provide appropriate system response. To overcome this difficulty, various control techniques have been proposed in literature, these includes an auto adjustable PI controller using MRAC technique [7], a standard two DOF PID with decoupling [8], PI controller tuning by CRA technique (characteristics ratio assignment) [9], an inverting decoupling technique [10]. The existing techniques are inadequate to provide robust responses, in the presence of disturbance in the plant dynamics.…”