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For the non-integer order process with time-delay, a design and tuning method of two-degree-of-freedom fractional order internal model controller is proposed. This method can over the disadvantages of single-degree-of-freedom PID controller that can not achieve the best performance of the command tracking characteristic and disturbance rejection characteristic at the same time. The time-delay term...
A new decoupling internal model controller design method was proposed for the decoupling problem of the multivariable time-delay systems in industrial processes. This method is based on the adjoint matrix of the controlled object model. According to the basic principle of inversion, decoupling compensator is designed firstly, and then the internal model controller is designed for the decoupling generalized...
In this paper, the well-known feedback controller design methods schemes such as Direct Synthesis (DS) method and PID design methods are compared. PID controllers are derived from Direct Synthesis (DS) controller by approximating the dead-time for FOPDT process models. In this work, DS and dead-time approximated PID controllers have been designed with various values of desirable closed loop time constants...
The aim of this paper is to design a Numerical Methods Controller (NMCr) based on a first order plus dead time (FOPDT) model of the actual process. The overall idea is to develop a general NMCr, which can be used for different self-regulating industrial processes, if they have a similar open loop response, such as an FOPDT model. Hence, this work summarises the easily and simplicity of numerical methods...
In this paper, a new design method of robust optimal proportional-integral (PI) controller with saturation characteristic is presented for different processes. Closed-loop feedback system is the nonlinear robust control system which can be equivalently transformed into robust linear switch system (RLSS) or robust autonomous switch system (RASS). The nonlinear robust optimal control problem can be...
A new method for PI-PD controller tuning based on direct synthesis for integrating and unstable processes with time delay. Guidelines are provided for selection of the desired closed loop transfer function in the direct synthesis method and adjustable parameter ω. Design for some typical unstable processes with time delay shows that the PI-PD controller can reduce the overshoot effectively and achieve...
Most of traditional robust problems focus on developing a robust controller to stabilize the dynamic system when system parameters perturb in certain bounded range. However, this paper studies the robust inverse problem, that is to say studying robust stability's inverse problem (RSIP) for linear systems. In other words, it needs to find at least a stable system parameters' perturbation space (SSPPS)...
In this paper, the control system of quadruple tank is designed which is based on the structure of experimental facility of quadruple tank and the method of H∞ loop shaping control. Firstly, The system model of the quadruple tank are acquired with system identification. Then the pre- and post-compensation are selected to make the singular values of the nominal controlled system become...
The paper presents the dynamic modeling and multi-objective robust Proportional-integral-Derivative (PID) control strategy for a nonlinear process continuous stirred tank reactor (CSTR) system. Motivated by the fact that many existing method involved in design an optimal PID controller based on single performance for the industrial process, multi-objective robust Proportional-integral-Derivative (PID)...
In the paper recent design and tuning methods of PID controllers are summarized briefly. Several decades have seen the widely application of PID controllers and the design and tuning methods have been of considerable development. Process model identification, PID controller structure design, PID parameters tuning methods and the use and expansions of PID are described in turn. PID parameter tuning...
Quantitative feedback theory (QFT) is a robust control design method. QFT quantitatively mirror the system uncertainty and design performance target to the Nichols chart, so the designed control system could ensure the performance. Due to the parameter uncertainty in tiltrotor conversion process, using QFT method design the flight control system for tiltrotor conversion. Simulation shows that the...
This document presents a new Internal Multi-Model Command controller design method for a linear system with a limited uncertain time delay. This design method is based on the use of a models collection to approximate the system functioning using Padé approximations; these models are inversed and multiplied by low pass filters in order to obtain a set of controllers to calculate the command value through...
In this paper we propose a methodology for the design of a control system for two-inputs-two-outputs processes. The methodology aims at improving the set-point following performance by employing a decoupler and a feedforward controller. The feedback controller is a standard decentralized PID controller while the feedforward controller is based on an approximated model of the decoupled system. A robustness...
The Ziegler-Nichols tuning rules have been very influential and have been used extensively in process industry. This paper presents an extension of the modified Ziegler-Nichols tuning rules for fractional PI controllers. The design method consists on minimizing a frequency objective function subject to a constraint on the maximum sensitivity function MS. In this paper it is also demonstrated that...
This paper presents new tuning rules for fractional PI control of processes that are typically found in process control. The rules are based on characterization of process dynamics by three parameters that can be obtained from a simple step response experiment. The rules are obtained by minimizing a frequency objective function subject to a constraint on the maximum sensitivity. Comparisons with classical...
In this paper, the robust design of the multi-loop PI controller for multivariable processes in the presence of the multiplicative input uncertainty is proposed. The paper deals with two major steps: as a first step, the analytical tuning rules of the multi-loop PI controller are derived from the basis of the generalized IMC-PID approach. Then, in the second step, the robust analysis is utilized for...
A modified internal model control (IMC) structure is proposed for representative industry process. The structure combines the control principle and new Luus-Jaakola (NLJ) optimization algorithm. The advantage of the structure is that set-point tracking and disturbance rejection can be designed separately. Design for a typical processes shows that the control structure can be tuned easily and achieve...
This paper studies the impact of intra-die random variability on low-power digital circuit designs, specifically, circuit timing failures due to intra-die variability. We identify a new low-Vdd statistical failure mode that is strongly supply-voltage dependent and also introduce a simple yet novel method for quantifying the effects of process variability on digital timing - a delay overlapping stage...
For several decades, the output from semiconductor manufacturers has been high volume products with process optimisation being continued throughout the lifetime of the product to ensure a satisfactory yield. However, product lifetimes are continually shrinking to keep pace with market demands. Furthermore there is an increase in dasiafoundrypsila business where product volumes are low; consequently...
In conventional optical data transmission schemes, electrical filters and/or optical filters are used to improve the quality of system performance. In this paper, improved design of dense wavelength division multiplexing (DWDM) optical systems is achieved by using a selective electrical filter assignment method. The methodology objective is to optimize system design and mitigate the effects of fiber...
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