scholarly journals Fractional-Order Control of Grid-Connected Photovoltaic System Based on Synergetic and Sliding Mode Controllers

Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 510
Author(s):  
Marcel Nicola ◽  
Claudiu-Ionel Nicola

Starting with the problem of connecting the photovoltaic (PV) system to the main grid, this article presents the control of a grid-connected PV system using fractional-order (FO) sliding mode control (SMC) and FO-synergetic controllers. The article presents the mathematical model of a PV system connected to the main grid together with the chain of intermediate elements and their control systems. To obtain a control system with superior performance, the robustness and superior performance of an SMC-type controller for the control of the udc voltage in the DC intermediate circuit are combined with the advantages provided by the flexibility of using synergetic control for the control of currents id and iq. In addition, these control techniques are suitable for the control of nonlinear systems, and it is not necessary to linearize the controlled system around a static operating point; thus, the control system achieved is robust to parametric variations and provides the required static and dynamic performance. Further, by approaching the synthesis of these controllers using the fractional calculus for integration operators and differentiation operators, this article proposes a control system based on an FO-SMC controller combined with FO-synergetic controllers. The validation of the synthesis of the proposed control system is achieved through numerical simulations performed in Matlab/Simulink and by comparing it with a benchmark for the control of a grid-connected PV system implemented in Matlab/Simulink. Superior results of the proposed control system are obtained compared to other types of control algorithms.

2010 ◽  
Vol 136 ◽  
pp. 153-157
Author(s):  
Yu Hong Du ◽  
Xiu Ming Jiang ◽  
Xiu Ren Li

To solve the problem of detecting the permeability of the textile machinery, a dedicated test system has been developed based on the pressure difference measuring method. The established system has a number of advantages including simple, fast and accurate. The mathematical model of influencing factors for permeability is derived based on fluid theory, and the relationship of these parameters is achieved. Further investigations are directed towards the inherent characteristics of the control system. Based on the established model and measuring features, an information fusion based clustering control system is proposed to implement the measurement. Using this mechanical structure, a PID control system and a cluster control system have been developed. Simulation and experimental tests are carried out to examine the performance of the established system. It is noted that the clustering method has a high dynamic performance and control accuracy. This cluster fusion control method has been successfully utilized in powder metallurgy collar permeability testing.


Author(s):  
Bahram Yaghooti ◽  
Ali Siahi Shadbad ◽  
Kaveh Safavi ◽  
Hassan Salarieh

In this article, an adaptive nonlinear controller is designed to synchronize two uncertain fractional-order chaotic systems using fractional-order sliding mode control. The controller structure and adaptation laws are chosen such that asymptotic stability of the closed-loop control system is guaranteed. The adaptation laws are being calculated from a proper sliding surface using the Lyapunov stability theory. This method guarantees the closed-loop control system robustness against the system uncertainties and external disturbances. Eventually, the presented method is used to synchronize two fractional-order gyro and Duffing systems, and the numerical simulation results demonstrate the effectiveness of this method.


2019 ◽  
Vol 7 (2) ◽  
pp. 37
Author(s):  
Jama S. Adam ◽  
Adebayo A. Fashina

This work presents the design of a 100kVA hybrid solar power system for Gollis University’s administrative block, Hargeisa, Somaliland. Prior to the system design, a preliminary field work on the site was performed to essentially measure the power/energy consumption of Gollis university’s administrative block. The results from the site survey was then used to select the appropriate equipment and instrument required for the design. This was achieved by calculating the energy consumption and then sizing the solar panel, battery, inverter and charge controller. The battery back-up time analysis at full load was also carried out to determine the effectiveness of the inverter size chosen. The inverter system was modeled and simulated using the MATLAB/Simulink software package. The simulation was used to study the reliability of the size of inverter chosen for the design, since the failure of most photovoltaic systems is ascribed to inverter failures. The results from the MATLAB/Simulink simulation showed that the inverter selected for the hybrid PV system has the ability to maximize the power produced from the PV array, and to generate sinusoidal AC voltage with minimum output distortion. The results also revealed that the PV solar system can provide a back-up time of 47.47 hours. The implications of the results are then discussed before presenting the recommendations for future works.  


Author(s):  
Salah Eddine Rhaili Et. al.

Variable structure strategies have shown an efficient performance in controlling nonlinear electrical power systems by reason of its strength to handle perfectly the unmodeled system dynamics. In this study, with the exponent reaching law, a robust enhancement method of sliding mode controller (SMC) based on a nonlinear fractional order sliding surface that consists of both fractional differentiation and integration is proposed and applied to control a high-power multiphase permanent magnet synchronous generator based direct-driven Wind Energy Conversion System (WECS), in order to improve the energy efficiency and reduce the produced chattering phenomenon of conventional SMC . Moreover, a new smooth and derivable nonlinear switching control function is applied to replace the traditional non-derivable nonlinear control law, to improve dynamic performance, static performance, and robustness of the system. The proposed strategy stability is investigated under Lyapunov theory. A comparative simulation of the new proposed approach with the conventional SMC and PI controller display the excellent performance, stability and high robustness of FOSMC, by improving the system efficiency up to 98.66%, compared to conventional SMC with 91,14%, while the PI control achieves 86, 2%.


2019 ◽  
pp. 20-66
Author(s):  
Heba Elkholy ◽  
Maki K. Habib

This chapter presents the detailed dynamic model of a Vertical Take-Off and Landing (VTOL) type Unmanned Aerial Vehicle (UAV) known as the quadrotor. The mathematical model is derived based on Newton Euler formalism. This is followed by the development of a simulation environment on which the developed model is verified. Four control algorithms are developed to control the quadrotor's degrees of freedom: a linear PID controller, Gain Scheduling-based PID controller, nonlinear Sliding Mode, and Backstepping controllers. The performances of these controllers are compared through the developed simulation environment in terms of their dynamic performance, stability, and the effect of possible disturbances.


Complexity ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Moshu Qian ◽  
Guanghua Zhong ◽  
Xinggang Yan ◽  
Heyuan Wang ◽  
Yang Cui

In this study, a closed-loop brain stimulation control system scheme for epilepsy seizure abatement is designed by brain-machine interface (BMI) technique. In the controller design process, the practical parametric uncertainties involving cerebral blood flow, glucose metabolism, blood oxygen level dependence, and electromagnetic disturbances in signal control are considered. An appropriate transformation is introduced to express the system in regular form for design and analysis. Then, sufficient conditions are developed such that the sliding motion is asymptotically stable. Combining Caputo fractional order definition and neural network (NN), a finite time fractional order sliding mode (FFOSM) controller is designed to guarantee reachability of the sliding mode. The stability and reachability analysis of the closed-loop tracking control system gives the guideline of parameter selection, and simulation results based on comprehensive comparisons are carried out to demonstrate the effectiveness of proposed approach.


2011 ◽  
Vol 356-360 ◽  
pp. 2393-2398
Author(s):  
Qi Qi Wei ◽  
Bei Yue Tan

photovoltaic system, optimum tilted angle, siphon principle, water treatment Abstract. Based on the recent research at home and abroad and the local meteorological data, this study aims to determine the optimum tilt angle of the solar-cell array surface and the best month on the system to achieve the optimal design of PV system. Full mechanical automatic control system is designed by using lever principle and siphon principle to realize the purpose of all-day and maintenance-free operational situation. It can replace the motor control system and at the same time,enjoys reliability, low cost, long life and energy conservation. The indoor and local river data of the experiment shows that this system has an evident effect on water decontamination. Furthermore, comparing with traditional aeration system. It has many advantages, for instance, it can save more than 20 thousand and carbon emission can be reduced by 683 ton and other aspects.


2019 ◽  
Vol 9 (20) ◽  
pp. 4269
Author(s):  
Zamee ◽  
Won

Grid-connected photovoltaic (PV) inverters are gaining attention all over the world. The optimal controller setting is key to the successful operation of a grid-connected PV system. In this paper, a novel plant propagation algorithm-based fractional order proportional-integrator (FOPI) controller for cascaded DC link voltage and inner current control of a grid-connected PV controller has been proposed, which outperforms particle swarm optimization-based PI and elephant herding optimization-based FOPI in terms of multicriteria-based analysis. The performance of the proposed controller also has been measured in terms of total harmonic distortion to maintain the appropriate power quality. Also, the proposed controllers were tested under various solar irradiance and voltage sag conditions to show the effectiveness and robustness of the controllers. The whole system is developed in OPAL-RT using MATLAB/Simulink and RT-LAB as a machine-in-loop (MIL) system to validate the performance in real time.


2010 ◽  
Vol 426-427 ◽  
pp. 106-108 ◽  
Author(s):  
De Gong Chang ◽  
Zhi Juan Xiao ◽  
Y.H. Liu ◽  
H. Li

Based on the analyses of the yarn tension and the mathematical model of the magnetic powder brake, the digital simulation of the yarn tension fuzzy control system was performed by using MATLAB Simulink. The relationship between the structure parameters and the system dynamic performance was then obtained, and the system scheme was justified.


2010 ◽  
Vol 426-427 ◽  
pp. 97-101 ◽  
Author(s):  
Fa Ye Zang

Based on the analysis of the belt misalignment of the metal V belt CVT, the reason of the belt misalignment has been discussed. In order to control the misalignment, an electro-hydraulic control system has been designed. After deeply analyzing the structure and principle of the electro-hydraulic control system, the mathematical model of the electro-hydraulic control system has been established. Being varieties of the working situation of car and the non-linearity of the electro-hydraulic control system, A Fuzzy PID algorithm has been designed. Then the simulation of the belt misalignment has been conducted, and the simulation results show that the electro-hydraulic control system and the fuzzy controller could not only control ratio, which had a higher accuracy of the stable state and a stronger robust of the driving condition, but also eliminated the belt misalignment, improved the dynamic performance of the metal V belt CVT.


Sign in / Sign up

Export Citation Format

Share Document