Owing to integrating the dense range of distinct electric power sources, high volume of power generation units, abrupt and continuous changes in load demand, and rising utilization of power electronics, the electric power system (EPS) is striving for high-performance control schemes to counterwork the concerns depicted above. Additionally, it is highly creditable to have the controller structure as simple as possible from a viewpoint of practical implementation. Thus, this paper describes a virgin application of fractional order proportional integral–fractional order proportional derivative (FOPI–FOPD) cascade controller for load frequency control (LFC) of electric power generating systems. The proposed controller includes fractional order PI and fractional order PD controllers connected in cascade wherein orders of integrator (
 $$\lambda$$
 ) and differentiator (
 $$\mu$$
 ) may be fractional. The gains and fractional order parameters of the controller are concurrently tuned using recently proposed dragonfly search algorithm (DSA) by minimizing the integral time absolute error (ITAE) of frequency and tie-line power deviations. DSA is the mathematical model and computer simulation of static and dynamic swarming behaviors of dragonflies in nature, and its implementation in LFC studies is very rare, unveiling additional research gap to be bridged. Performance of the advocated approach is first explored on popular two-area thermal PS with/without governor dead band (GDB) nonlinearity and then on three-area hydrothermal PS with suitable generation rate constraints. To highlight the prominence and universality of our proposal, the work is extended to single-/multi-area multi-source EPSs. Several comparisons with DSA optimized FOPID controller and the relevant recent works for each test system indicate the contribution of proposed DSA optimized FOPI–FOPD cascade controller in alleviating settling time/undershoot/overshoot of frequency and tie-line power oscillations.

Design of new fractional order PI–fractional order PD cascade controller through dragonfly search algorithm for advanced load frequency control of power systems

In our world of today developing incredibly fast, load frequency control (LFC) is an indispensable and vital element in increasing the standard of living of a country by providing a good quality of electric power. To this end, rapid and notable development has been recorded in LFC area. However, researchers worldwide need for the existence of not only effective but also computationally inexpensive control algorithm considering the limitations and difficulties in practice. Hence, this paper deals with the introduction of (1 + PD)-PID cascade controller to the relevant field. The controller is simple to implement and it connects the output of 1 + PD controller with the input of PID controller where the frequency and tie-line power deviation are applied to the latter controller as feedback signals also, which is the first attempt made in the literature. To discover the most optimistic results, controller gains are tuned concurrently by dragonfly search algorithm (DSA). For the certification purpose of the advocated approach, two-area thermal system with/without governor dead band nonlinearity is considered as test systems initially. Then single/multi-area multi-source power systems with/without a HVDC link are employed for the enriched validation purpose. The results of our proposal are analyzed in comparison with those of other prevalent works, which unveil that despite its simplicity, DSA optimized (1 + PD)-PID cascade strategy delivers better performance than others in terms of smaller values of the chosen objective function and settling time/undershoot/overshoot of the frequency and tie-line power deviations following a step load perturbation.

(1 + PD)-PID cascade controller design for performance betterment of load frequency control in diverse electric power systems

Owing to nonlinear structure and uncertain load demand characteristics, expert and intelligent automatic generation control (AGC) is inevitable for coherent operation and control of electric power system. Hence, in this paper, to mitigate the frequency and power deviations efficiently under sudden load demand conditions, a novel fractional-order fuzzy PID (FOFPID) controller is suggested in AGC of restructured multi-area multi-source hydrothermal power systems. The parameters of FOFPID controller are optimized by utilizing bacterial foraging optimization algorithm. The controller is implemented on restructured two- and three-area systems. It is observed that the advocated method shows superiority over fuzzy PID, fractional-order PID and conventional PID control schemes. Energy storage units such as redox flow batteries (RFB) which show extremely long charge–discharge life cycle and outstanding quick response to alleviate the system oscillations under disturbances have further been incorporated into the studied systems to analyze their efficacy in boosting AGC performance. Analysis of results reveals that with RFB, system transient performance improves significantly. It is also observed that the obtained results satiate the AGC requirement under different power transactions taking place in a deregulated market in the presence/absence of appropriate generation rate constraint treated for thermal and hydro plants. Finally, the robustness of the presented approach is demonstrated against the wide variations in the system parameters and initial loading condition.

AGC of restructured multi-area multi-source hydrothermal power systems incorporating energy storage units via optimal fractional-order fuzzy PID controller

https://robots.iopscience.iop.org/article/10.1088/2631-6331/abff36/pdf

Treatments of natural fiber as reinforcement in polymer composites—a short review

Control of pH processes is highly challenging due to high nonlinearity and sensitivity around the equilibrium point. PID controllers being simple and the most widely used perform poorly with changing set-point and are limited to certain operating regions. Thus, they are inadequate for such applications without upgrading. In this paper, a fractional order set-point weighted PID (
 $$\mathrm {SWPI^{\lambda }D^{\mu }}$$
 ) controller is designed for pH neutralization process. The objective is to achieve adequate set-point tracking and effective load regulation through smooth control action. The controller parameters are tuned using accelerated particle swarm optimization which uses only global best position to achieve faster convergence. Simulation results show that for both standard and industrial configurations of the proposed approach, better performance in terms of set-point tracking, disturbance rejection and sensitivity to model parameter variation is achieved compared to PID, fractional order PID (
 $$\mathrm {PI^{\lambda }D^{\mu }}$$
 ) and SWPI-D.

Fractional Order Set-point Weighted PID Controller for pH Neutralization Process Using Accelerated PSO Algorithm

In this paper, a fractional-order proportional–integral–derivative (FOPID) controller for automatic generation control (AGC) scheme has been designed utilizing the big bang–big crunch algorithm. An AGC scheme in a deregulated electricity market environment has been developed. The objective was to compute optimal FOPID controller parameters so that on a load perturbation generator can regulate power, to achieve the best dynamic response of frequency. FOPID controller has five parameters to be tuned and provides two more degrees of freedom in comparison with the conventional PID controller. The performance of FOPID controller has been checked on 2-area power system and 75-bus real power system. A comparative study is also carried out between the results of FOPID and PID controllers. The obtained results demonstrate the effective performance of the FOPID controller and show the success and validity of FOPID controller in terms of performance parameters, i.e., settling time and oscillations.

Deregulated Multiarea AGC Scheme Using BBBC-FOPID Controller

This paper focuses on selecting optimal process parameters for uniform single-layer weld bead deposition and the characterization of structures manufactured by GMAW-based wire arc additive manufacturing (WAAM) process. The results reveal that the obtained grain structures vary due to the local thermal cycle. Near to the base of the fabricated part, ferrite with pearlite structures is observed. At the same time, the observed grains become coarser along the deposition direction. Again adjacent to the final layer, finer grains are observed with ferrite and thin strips of bainite, which has been confirmed through XRD analysis. Also, the formation of different chemical compounds such as ferrite, cementite, bornite, and martensite has been identified at different layers. Investigations of surface defects using dye penetration test and corrosion behavior of the component using the weight loss method have also been conducted. The observed surface defects like cracks and porosity are primarily present in the interface of the upper layers. The measured Vickers micro-hardness is found different in different wall structures. The micro-hardness values in the flat and circular wall are recorded as 162.806 HV and 172.191 HV, respectively.

Parametric study and characterization of wire arc additive manufactured steel structures

Study of natural fibre composite material and its hybridization techniques

Microgrids (MGs) provides an interconnection of energy consuming components like various loads and generation components i.e. microsources (MSs) preferably the renewable energy resources (RESs) viz. solar PV and wind turbines. These RESs are interfaced to the low voltage (LV) distribution system through power electronics inverters. During islanded operation of MG, voltage and frequency control are of utmost importance. This paper presents a voltage regulation strategy based on the principle of robust decentralized output-feedback type controller implemented as linear quadratic regulator (LQR). It considers various uncertainties viz. load variation and deviations in the neighboring bus parameters within the MG to obtain a robust optimal operation. A standard MG model having two inverter based sources with dedicated RLC type loads is taken as the test system. The Matlab/Simulink based simulation of various test cases viz. set-point tracking under bounded load variation, load perturbation and neighboring bus dynamics are performed to verify the effectiveness of the proposed voltage controller.

Robust Decentralized Output-Feedback Type LQR Voltage Controller for Inverter-Based Microgrid

This study presents the µPMU deployment technique in the reconfigurable medium voltage active distribution network. For this, the multi-objective function-based approach is utilized targetting the complete observability in all the realtime configuration with minimum numbers of µPMU and maximum observability redundancy for the base configuration. The effectiveness of the proposed method is demonstrated on standard IEEE 33 and 118-node network considering multiple configurations. The results validate that the proposed method successfully locate the µPMU in the reconfigurable active distribution network.

Vishal Kumar

Papers

Deregulated Multiarea AGC Scheme Using BBBC-FOPID Controller

Parametric study and characterization of wire arc additive manufactured steel structures

Study of natural fibre composite material and its hybridization techniques

Robust Decentralized Output-Feedback Type LQR Voltage Controller for Inverter-Based Microgrid

MILP Based Deployment of Micro-PMU in Reconfigurable Active Distribution Network