Advanced Control for Applications最新文献

Designing a controller for a process plant typically modeled as a first or second-order system with dead time involves an efficient and accurate estimation of its parameters. Since many process plants are characterized as second-order plus dead time (SOPDT) overdamped or critically damped systems, this study presents a straightforward parameter estimation method using transient response data from a step input at three specific time instants. Two-time domain performance indices (PIs), $��T_R�$ (= $��\frac{t_{90}}{t_{10}}�$ for system dead time = 0 and $��\frac{�t_{90}�-�t_5��}{�t_{10}�-�t_5��}�$ for system dead time ≠ 0; $��t_5�$, $��t_{10}�$ and $��t_{90}�$ are respectively the times at which the response reaches 5%, 10% and 90% of the steady-state response) and $��f_r�$ (reciprocal of rise time $��t_r�$) are proposed in this work. Correlations are established between these PIs and the pa

The purpose of this work is an arrangement of distributed generation (DG) in radial distribution networks (RDNs) in an adequate way. An efficient method, named arithmetic optimization algorithm (AOA) is used for that purpose. The intention for effective DG posting is to decrease the power loss and upgrade the voltage shape and voltage steadiness magnification in RDNs. The demonstration of the suggested AOA method has been made on 33-bus, 69-bus, 85-bus, and 118-bus RDNs for optimum orientation and capacity of DGs with distinct power factors (unity, fixed, and optimal). By using this projected technique, the execution of RDNs is improved with respect to voltage stability maximization, voltage fluctuation mitigation, and also reduction of real power loss. The AOA method which is recommended here, grants a better solution than several optimization techniques found in the literature. This recommended AOA technique provides the percentage improvement of power loss for case 1 to case 3 (65.50%, 86.48%, and 94.43%), (69.16%, 90.80%, and 98.10%), (44.57%, 66.61%, and 80.26%), and (60.34%, 88.80%, and 90.31%) for 33, 69, 85, and 118-bus systems, respectively. The percentage improvement in voltage deviation minimization for case 1 to case 3 are (99.53%, 99.83%, and 99.84%), (99.88%, 99.91%, and 99.92%), and (97.53%, 98.98%, and 99.16%) for 33, 69, and 118-bus systems, respectively. For different test systems (33, 69, and 118-bus) improvements in voltage stability index maximization for case 1 to case 3 are (31.33%, 31.80%, and 31.81%), (30.15%, 31.25%, and 31.25%), and (37.78%, 39.23%, and 40.88%), respectively.

Linear time invariant (LTI) block diagrams—and the associated transfer functions—are profoundly inadequate for multi-loop control system design. A practitioner has to have a thorough understanding of the physical uncertainties—and of their inter-dependencies—in the different parts of an interconnected system, or in a given block diagram. Lack of attention to, or understanding of, such causal interactions has led to ill-advised reliance on cascaded control in practice—and to consternation when cascading fails to yield the expected improvement over a single-loop design.

The four-switch Buck-Boost (FSBB) converter are widely used in combination with other isolated converter to extend the voltage range capability of the overall structure. When the converter operates in buck-boost mode and boost mode, it exhibits a right half plane zero (RHPZ) in the control to output transfer function. This characteristic would cause negative impact to stability of the converter. In order to eliminate the RHPZ, a novel modulation method is proposed in this paper. The buck mode is introduced to the modulation to adjust the voltage gain, and the corresponding average state space modeling for the FSBB with the proposed modulation is established. The simulation of the converter with the proposed modulation method and traditional modulation are presented. Finally, experiment results by hardware in the loop (HIL) platform is employed to verity the correctness of theoretical analysis results.

The study of missile guidance systems is a well-known nonlinear control engineering area of research. To enhance the control performance of a missle guidance system, several technologies have been proposed in existing works. To resolve the weighting matrix selection issue of a linear quadratic Gaussian (LQG) controller for the surface-to-air missile guidance control system, this study utilizes the particle swarm optimization (PSO) technique. Selecting the best state (Q) and input (R) weighting matrices is a significant difficulty in the design of the LQG controller for real-time applications since it affects the controller's performance and optimality. The weighting matrices are often chosen by a trial-and-error method that not only complicates the design but also does not yield optimal outcomes. Therefore, in this paper, a PSO method is developed and used in the design of the linear quadratic regulator (LQR) and LQG controllers for the surface-to-air missile control system to choose the elements of the Q and R matrices in the best possible way. Finally, a comparative analysis between the designed controllers was presented. The results shows that a good performance was achieved by using the proposed PSO-tuned design process. The LQG and LQR are designed by manually adjusting the weighting matrices and utilizing an intelligent procedure, PSO algorithm which achieved optimal results. Further results indicate that the designed controllers, the PSO tuned LQR and LQG achieved a better performance over the manually adjusted LQR and LQG controllers.