Saad Alghuwainem - Academia.edu (original) (raw)

Papers by Saad Alghuwainem

Power cables are vulnerable to failure due to aging or defects that occur with the passage of tim... more Power cables are vulnerable to failure due to aging or defects that occur with the passage of time under continuous operation and loading stresses. PD detection and characterization provide information on the location, nature, form and extent of the degradation. As a result, PD monitoring has become an important part of condition based maintenance (CBM) program among power utilities. Online partial discharge (PD) localization of defect sources in power cable system is possible using the time of flight method. The information regarding the time difference between the main and reflected pulses and cable length can help in locating the partial discharge source along the cable length. However, if the length of the cable is not known and the defect source is located at the extreme ends of the cable or in the middle of the cable, then double ended measurement is required to indicate the location of PD source. Use of multiple sensors can also help in discriminating the cable PD or local/ e...

2019 8th International Conference on Modeling Simulation and Applied Optimization (ICMSAO), 2019

The increase in demand for clean sources of energy is getting more attention in recent time. Elec... more The increase in demand for clean sources of energy is getting more attention in recent time. Electric vehicle (EV) is an important area to fulfil this demand. However, one of the major obstacles in the growth of EV is the longer charging time. Therefore, there is a definite need for the reduction of charging time in EVs. Constant current charging of EV can help to solve this problem. That's why, the role of DC-DC converter is very important. DC-DC converters are commonly utilized in electronic devices such as mobile phones, computers etc. This paper presents the possibility of grid connected constant current charging of EV with buck DC-DC converter through fuzzy logic control (FLC). FLC is easy to implement without the requirement of intensive mathematical modelling. The complete model of the considered system has been developed in MATLAB/Simulink. The achieved simulation results show the viability and capability of the proposed scheme.

IEEE Transactions on Energy Conversion, 1999

Due to speed fluctuations of unregulated wind-turbines, the terminal voltage may increase to dang... more Due to speed fluctuations of unregulated wind-turbines, the terminal voltage may increase to dangerously high levels which have been reported to cause capacitor failure at windfarms. This paper examines the steady-state analysis and performance characteristics of a stand-alone self-excited induction generator (SEIG) when a transformer is connected to its terminals to supply the load at a different voltage level or to step-up the terminal voltage for transmission. The transformer tends to saturate at higher speeds, and thus absorbs the excess reactive power and limits the increase in terminal voltage and improves voltage regulation. Transformer saturation introduces an additional nonlinearity which complicates the analysis considerably. A technique for formulating and solving the system's equations including transformer saturation is presented. The same technique is also applicable when the load itself is nonlinear. Experimental investigation has confirmed the accuracy of the pro...

Applied Soft Computing, 2019

Abstract This paper proposes an enhancement of the meta-heuristic whale optimization algorithm (W... more Abstract This paper proposes an enhancement of the meta-heuristic whale optimization algorithm (WOA) for maximum power point tracking (MPPT) of variable-speed wind generators. First of all, twenty-three benchmark functions tested the enhanced whale optimization algorithm (EWOA). Then the statistical results of EWOA compared with the results of other algorithms (WOA, salp swarm algorithm (SSA), enhanced SSA (ESSA), grey wolf optimizer (GWO), augmented GWO (AGWO), and particle swarm optimization (PSO). Also, the non-parametric statistical test and convergence curves proved the superiority and the speed of the EWOA. After that, the EWOA and WOA are implemented to design optimal Takagi–Sugeno fuzzy logic controllers (FLCs) to enhance the MPPT control of variable-speed wind generators. Moreover, real wind speed data has confirmed the robustness of optimal EWOA-MPPT. In conclusion, the simulation results revealed that the EWOA is a promising algorithm to be applied for solving different engineering problems.

Engineering Applications of Artificial Intelligence, 2020

Abstract Due to the extensive penetration of wind power plants (WPPs) into the grid, grid codes h... more Abstract Due to the extensive penetration of wind power plants (WPPs) into the grid, grid codes have been imposed such that the WPPs stay linked to the grid during faults for a period to maintain the grid stability. This paper designs optimal Sugeno fuzzy logic controllers (FLCs) to improve the fault ride-through (FRT) ability of grid-connected WPPs. The meta-heuristic algorithm, whale optimization algorithm (WOA), is utilized to design the control rules and the Gaussian memberships of eight Sugeno FLCs, simultaneously, by minimizing the high dimensional multi-objective fitness function. The WOA-FLCs and the grid-connected gearless permanent magnet synchronous generator driven by a variable-speed wind turbine (VSWT-PMSG) are modeled using PSCAD/EMTDC environment. The effectiveness of the FRT ability of grid-connected VSWT-PMSG is investigated during balanced and unbalanced grid fault conditions. The simulation results of using WOA-FLCs revealed fast time response, less overshoot, and small steady-state error compared with those achieved by using a genetic algorithm (GA) and grey wolf optimizer (GWO).

Electric Power Systems Research, 2020

Applied Energy, 2019

Abstract This article proposes an accurate and straightforward method for modeling and simulation... more Abstract This article proposes an accurate and straightforward method for modeling and simulation of photovoltaic (PV) modules. The main target is to find the nine-parameter of a three-diode (TD) model based on the datasheet parameters, which are given by all commercial PV modules. The objective function is formulated based on short circuit, open circuit, power derivative, and maximum power equations. Two parameters (parallel resistance and photo-generated current) are calculated analytically and rest parameters are optimally designed using the sunflower optimization (SFO) algorithm. The presented method is applied to model three types of commercial PV modules (multicrystal KC200GT, poly-crystalline MSX-60, and mono-crystalline CS6K-280M). The optimal nine-parameters obtained in this paper are paralleled with that attained by other approaches. In order to assess the efficiency of the offered approach, I-V and P-V characteristics are validated with measured data under various temperatures and solar irradiations. The error among these results records a value less than 0.5%. Therefore, the simulation results indicate an excellent agreement with the measured data. This proposed approach can be utilized to model any marketable PV module based on given datasheet parameters only.

Engineering Applications of Artificial Intelligence, 2019

Abstract This article presented a novel modification and application of the salp swarm algorithm ... more Abstract This article presented a novel modification and application of the salp swarm algorithm (SSA) that is inspired by the chain behavior of salp fishes that live in deep oceans. Firstly, the enhanced salp swarm algorithm (ESSA) is proposed to improve the inadequate results of the SSA compared to the other algorithms, especially for the high dimensional functions. The ESSA algorithm is verified using twenty-three benchmark test functions and compared with the original SSA algorithm and other algorithms. The statistical analysis of the obtained results revealed that the ESSA algorithm is significantly improved and the convergence curves showed the fast convergence to the best solution. Secondly, The SSA and ESSA algorithms are applied to enhance the maximum power point tracking and the fault-ride through ability of a grid-tied permanent magnet synchronous generator driven by a variable speed wind turbine (PMSG-VSWT). The multi-objective function (integral squared error) is minimized to find the high dimensional parameters of Takagi–Sugeno–Kang fuzzy logic controllers (TSK-FLC) used in the cascaded control of grid-tied PMSG-VSWT. The simulation results using PSCAD/EMTDC proved that the produced power when using ESSA is higher than when using SSA which mean higher efficiency and lower cost.

The Journal of Engineering, 2017

The output power of wind farms is fluctuating as a result of the wind speed variation. These powe... more The output power of wind farms is fluctuating as a result of the wind speed variation. These power fluctuations disturb the quality of voltage and frequency of the grid. The fluctuated power can be smoothed via many methods such as controlling the pitch angle of blades, the rotor inertia, and using the energy storage systems (ESSs). These ESSs are mostly installed in the renewable energy for load levelling with cost limitations. Owing to the high cost of ESSs, it is required to utilise and enhance different power control techniques. This study introduces different and recent proposed methods and enhancements to smoothen the output power of permanent-magnet synchronous generator driven directly (gearless) by a variable-speed wind turbine. Fuzzy logic control, sliding mode control, and evolutionary algorithms are used to enhance the control performance of pitch angle, machine-side converter, and DC-DC converter of ESS.

2000 Canadian Conference on Electrical and Computer Engineering. Conference Proceedings. Navigating to a New Era (Cat. No.00TH8492)

This paper presents steady-state analysis and control of a wind-driven stand-alone 3-phase self-e... more This paper presents steady-state analysis and control of a wind-driven stand-alone 3-phase self-excited induction generator supplying a 3-phase induction motor. The induction motor drives mechanical load (such as a water-pump) which has a given speed-torque characteristics. The steady-state equivalent circuit of the system is analyzed using the node-admittance method and the results are utilized to determine the optimum operating conditions for maximum utilization efficiency.

1997 IEEE International Electric Machines and Drives Conference Record

Due to speed fluctuations of unregulated wind-turbines, the terminal voltage may increase to dang... more Due to speed fluctuations of unregulated wind-turbines, the terminal voltage may increase to dangerously high lcvels which have been reported to cause capacitor failure at windfarms. This paper examines the steady-state analysis and performance characteristics of astand-alone self-excited induction generator (SEIG) when a transformer is connected to its terminals to supply theloadat adifferent voltagelevel or to step-up the terminal voltage for transmission. The transformer tends to saturate at higher speeds, and thus absorbs the excess reactive power and limits the increase in terminal voltage and improves voltage regulation. Transformer saturation introduces an additional non-linearity which copmplicates the analysis considerably. A technique for formulating and solving the system's equations including transformer saturation is presented. The same technique is also applicable when the load itself is nonlinear, Experimental investigation has confirmed the accuracy of the proposed technique.

Solar Energy Materials and Solar Cells, 1997

A solar cell array is inherently a nonlinear device consisting of several solar cell modules conn... more A solar cell array is inherently a nonlinear device consisting of several solar cell modules connected in series-parallel combinations to provide the desired DC voltage and current. At a fixed insolation level, the terminal voltage decreases nonlinearly as the load current increases. Due to this nonlinearity, it is difficult to determine analytically the operating point at which the output power is maximum; a condition required for maximum utilization efficiency of the array. Iterative techniques are normally used to determine this operating condition. These techniques are lengthy, time-consuming, and have to be repeated for any change in the array's parameters, temperature, and insolation level. In this paper, an accurate closed-form solution is derived in terms of the array's parameters and solar insolation level. This solution is useful to the system designer or researcher as a fast and accurate tool for system design and performance analysis.

IEEE Transactions on Energy Conversion, 1999

This paper examines the steady-state analysis and performance of an isolated three-phase self-exc... more This paper examines the steady-state analysis and performance of an isolated three-phase self-excited induction generator (SEIG) driven by regulated and unregulated turbine. For the case of a regulated turbine the equivalent circuit is solved with speed as a constant parameter, while for the unregulated turbine, the speed is considered as a variable which depends on the shaft torque according to the turbine characteristics. The no-load speed is considered as a constant independent parameter, which depends on wind speed which is assumed constant in this analysis. The steady-state equivalent circuit is solved using the nodeadmittance method, and the shaft torque is expressed in terms of the rotor current. The Newton-Raphson method is used to solve the system nonlinear equations. For the present investigation, a linear speed-torque characteristic is considered, but the method of analysis applies equally well to nonlinear characteristics. Experimental investigations on a 1-kW three-phase induction generator driven by a separately excited dc shunt motor have confirmed the accuracy of the proposed method of analysis.

Smart Grid and Renewable Energy, 2021

The target of this paper is to model a Maximum Power Point Tracker (MPPT) using a Fuzzy Logic Con... more The target of this paper is to model a Maximum Power Point Tracker (MPPT) using a Fuzzy Logic Control (FLC) algorithm and to investigate its behavior with a battery load. The advantage of this study over other studies in this field is that it considers a battery load rather than the commonly used resistive load especially when we deal with the relationship between MPPT and system load. The system is about 60 kW which is simulated under various environmental conditions by Matlab/Simulink program. For this type of non-linear application, FLC naturally offers a superior controller for the real load case. The artificial intelligence approach also benefits from this method for overcoming the complexity of nonlinear system modelling. The results show that FLC provides high performance for MPPT of PV system with battery load due to its low settling time and limited oscillation around the steady state value. These are assistant factors for increasing battery life.

The Journal of Engineering, 2017

2019 54th International Universities Power Engineering Conference (UPEC)

Due to the stochastic nature of wind speed, energy storage systems are used to reduce the fluctua... more Due to the stochastic nature of wind speed, energy storage systems are used to reduce the fluctuations of the output power of wind farms. In this paper, the superconducting magnetic energy storage (SMES) is used to smoothen the output power of a permanent magnet synchronous generator (PMSG) driven by a variable speed wind turbine. The PMSG is connected to the grid through a back-to-back converter. The SMES is connected to the DC link of the back-to-back converter through an asymmetrical converter. The Grey Wolf Optimizer (GWO) is used to find the optimal parameters of a proportionalintegral (PI) controller used to regulate the charge and discharge operation of the SMES unit. The grid-tied PMSG wind turbine system is modelled and simulated using PSCAD/EMTDC software. Wind speed data measured at Zaafarana wind farm, Egypt is used in evaluating the system's performance. Simulation results revealed that the optimal controlled SMES has smoothened the output wind power and reduced the total harmonic distortion of it.

Applied Intelligence

This article offers a new physical-based meta-heuristic optimization algorithm, which is named Tr... more This article offers a new physical-based meta-heuristic optimization algorithm, which is named Transient Search Optimization (TSO) algorithm. This algorithm is inspired by the transient behavior of switched electrical circuits that include storage elements such as inductance and capacitance. The exploration and exploitation of the TSO algorithm are verified by using twenty-three benchmark, where its statistical (average and standard deviation) results are compared with the most recent 15 optimization algorithms. Furthermore, the non-parametric sign test, p value test, execution time, and convergence curves proved the superiority of the TSO against other algorithms. Also, the TSO algorithm is applied for the optimal design of three well-known constrained engineering problems (coil spring, welded beam, and pressure vessel). In conclusion, the comparison revealed that the TSO is promising and very competitive algorithm for solving different engineering problems.

Electronics

This paper depicts a new attempt to apply a novel transient search optimization (TSO) algorithm t... more This paper depicts a new attempt to apply a novel transient search optimization (TSO) algorithm to optimally design the proportional-integral (PI) controllers. Optimal PI controllers are utilized in all converters of a grid-linked permanent magnet synchronous generator (PMSG) powered by a variable-speed wind turbine. The converters of such wind energy systems contain a generator-side converter (GSC) and a grid-side inverter (GSI). Both of these converters are optimally controlled by the proposed TSO-based PI controllers using a vector control scheme. The GSC is responsible for regulating the maximum power point, the reactive generator power, and the generator currents. In addition, the GSI is essentially controlled to control the point of common coupling (PCC) voltage, DC link voltage, and the grid currents. The TSO is applied to minimize the fitness function, which has the sum of these variables’ squared error. The optimization problem’s constraints include the range of the proport...

2019 8th International Conference on Modeling Simulation and Applied Optimization (ICMSAO), 2019

IEEE Transactions on Energy Conversion, 1999

Applied Soft Computing, 2019

Engineering Applications of Artificial Intelligence, 2020

Electric Power Systems Research, 2020

Applied Energy, 2019

Engineering Applications of Artificial Intelligence, 2019

The Journal of Engineering, 2017

2000 Canadian Conference on Electrical and Computer Engineering. Conference Proceedings. Navigating to a New Era (Cat. No.00TH8492)

1997 IEEE International Electric Machines and Drives Conference Record

Due to speed fluctuations of unregulated wind-turbines, the terminal voltage may increase to dang... more Due to speed fluctuations of unregulated wind-turbines, the terminal voltage may increase to dangerously high lcvels which have been reported to cause capacitor failure at windfarms. This paper examines the steady-state analysis and performance characteristics of astand-alone self-excited induction generator (SEIG) when a transformer is connected to its terminals to supply theloadat adifferent voltagelevel or to step-up the terminal voltage for transmission. The transformer tends to saturate at higher speeds, and thus absorbs the excess reactive power and limits the increase in terminal voltage and improves voltage regulation. Transformer saturation introduces an additional non-linearity which copmplicates the analysis considerably. A technique for formulating and solving the system's equations including transformer saturation is presented. The same technique is also applicable when the load itself is nonlinear, Experimental investigation has confirmed the accuracy of the proposed technique.

Solar Energy Materials and Solar Cells, 1997

IEEE Transactions on Energy Conversion, 1999

Smart Grid and Renewable Energy, 2021

The Journal of Engineering, 2017

2019 54th International Universities Power Engineering Conference (UPEC)

Applied Intelligence

Electronics