Firas Obeidat

This paper addresses the optimal design of grid connected single-phase seven levels Cascaded H-bridge (CHB) converter with harsh nonlinear load based on Asymmetric Selective Harmonic Current and Voltage Modulation-PWM (ASHCVM-PWM) technique to meet voltage and current quality standard as mentioned in IEEE-519. Grey Wolf Optimization (GWO) technique is used to find the optimal number and values of switching angles, optimal filter value, and optimal modulation index, to meet voltage and current harmonic requirements for grid current and Point of Common Coupling (PCC) voltage. 18, 22, 26, and 30 switching angles are used to find the optimal number of them. MATLAB software is used to run the system according to optimal parameters to show the performance of the system and to show which solution is the optimal one according to the harmonic values for each solution. The results shows that when the number of switching angles is 30; TDD, THD and harmonic percentages have the least values.

The increase investment of renewable energy resources (RESs) into power systems, such as solar photovoltaics (PVs), introduces additional uncertainty in transmission line loading. This uncertainty adds challenges to cascading failure analyses of power systems especially in future power scenarios of high penetration of RESs. In this paper, cascaded failures of power systems caused by the sequence tripping of transmission lines in the presence of RESs (mainly PV systems) is analyzed. By studying the lost power and the line failure probability, the potential impact of integrating more RESs on cascaded failures is investigated. In this regard, the uncertainties of RESs are examined by adding PV systems probability distribution function that reflects the solar irradiance for a typical day. A transmission-boosting approach is proposed in this paper to minimize the impact of failure risk to mitigate the possibility of the cascaded failure caused by the increased penetration of RESs. This paper presents a systematic approach to mitigate the risk of cascading failures via reconducting of transmission lines. Simulation studies for different penetration scenarios of PV systems have been carried out to test the impact on the cascaded failure and to validate the proposed transmission-boosting approach. The results in this paper imply that the increase in penetration of PV systems in the power grid would increase the potential of both cascaded failure risk and occurrence. In addition, the results have shown the efficacy of the proposed transmission-boosting approach in minimizing the cascaded failure risk when implemented. The findings have been validated using the modified version of the IEEE 39-bus test system modeled and simulated in Matlab.

A combined PSO-ANN control is proposed in this work to achieve the best voltage regulation in a distribution network, based on quick response and minimum average voltage deviation. The Jordanian Sabha Distribution Network (JSDN) with PV Farms is used as a real case study to examine a voltage variation issue. Two STATCOMs are used to solve the voltage fluctuation problem on the network’s three buses. The required reactive powers of STATCOMs for voltage regulation during load variation are calculated in offline mode using a particle swarm optimization (PSO) algorithm. Despite its high performance in solving voltage issue in the JSDN network, the PSO controller is unable to react promptly to dynamic changes in the network. An artificial neural network (ANN) is therefore suggested as an online mode controller for quick and efficient voltage regulation. The offline dataset is used to train the ANN for online voltage regulation utilizing the MATLAB-Tool Box. At an average voltage deviation (AVD) of 1.168%; (whereas an acceptable one is 6%), the results revealed the proposed ANN controller’s competence for voltage regulation in the distribution network. Moreover, to find the best position based on an efficient voltage regulation, many sites for STATCOMs are taken into consideration.

Hydrogen has universally been considered a reliable source of future clean energy. Its energy conversion, processing, transportation, and storage are techno-economically promising for sustainable energy. This study attempts to maximize the production of H₂ energy using nanocatalysts from waste aluminum chips, an abundant metal that is considered a potential storage tank of H₂ energy with high energy density. The present study indicates that the use of waste aluminum chips in the production of H₂ gas will be free of cost since the reaction by-product, Al₂O₃, is denser and can be sold at a higher price than the raw materials, which makes the production cost more efficient and feasible. The current framework investigates seven different copper oxide-based graphene nanocomposites that are synthesized by utilizing green methods and that are well-characterized in terms of their structural, morphological, and surface properties. Reduced graphene oxide (rGO) and multi-layer graphene (MLG) are used as graphene substrates for CuO and Cu₂O NPs, respectively. These graphene materials exhibited extraordinary catalytic activity, while their copper oxide composites exhibited a complete reaction with feasible techno-economic production. The results revealed that the H₂ production yield and rates increased twofold with the use of these nanocatalysts. The present study recommends the optimum reactor design considerations and reaction parameters that minimize water vaporization in the reaction and suggests practical solutions to quantify and separate it. Furthermore, the present study affords an economic feasibility approach to producing H₂ gas that is competitive and efficient. The cost of producing 1 kg of H₂ gas from waste aluminum chips is USD 6.70, which is both economically feasible and technically applicable. The unit cost of H₂ gas can be steeply reduced by building large-scale plants offering mass production. Finally, the predicted approach is applicable in large, medium, and small cities that can collect industrial waste aluminum in bulk to generate large-scale energy units.

Experimental work has been carried out to study the possibility of combining a conventional solar water collector with a hybrid device, developed previously and known as PV/T system, in order to obtain hot water with temperature above 40oC. The effect of the combination on the productivity of hot...

This paper presents the details of 13 rooftop PV systems installed at Philadelphia University (PU) in Amman-Jordan and gives an assessment of these PV systems in terms of the design layout that harmonize the university building’s roofs architectural style, and also in terms of energy generated compared with the university energy consumption using real data of the year 2019. Technoeconomic performance metrics and socio environmental assessment of the PV systems are also performed. The analysis shows that more than 99% of the energy needs of the university are met by solar energy. This energy generated is equivalent to 1587 metric tons of CO2 eq. This amount of CO2 avoided is equivalent to 26,236 tree seedings grown for 10 years. This emphasizes the main conclusion that Philadelphia University has taken the right decision with the installation of these systems that represent a great step towards the university sustainability. Copyright © 2021 Praise Worthy Prize - All rights reserved.

This paper initially discusses the reliability of a 250W Photovoltaic (PV) micro inverter. Using the bill of materials the reliabilities of the main, gate drive, power supply, current and voltage sensing and microprocessor circuits were investigated, and the failure rate and Mean Time Between Failure (MTBF) calculated. The sum of component failure rates equals the complete PV micro inverter failure rate. To account for temperature effects the component failure rate was calculated for each inverter operating temperature, and multiplied by the percentage occurrence of this operating temperature to obtain a weighted failure rate. A similar procedure was used to calculate the failure rate for the main circuits of a 4.6kW & a 4.5kW multi-string inverter. All calculations are based on MIL-17F N2 method.

This paper presents two topologies to connect HVDC offshore wind farm into the grid, the offshore part consist of five units; in the first topology, each unit contains a permanent magnet synchronous generator (PMSG) connected to a three level neutral point clamped converter (3L-NPC) to control the generator speed by using a maximum power point tracking (MPPT) control. The offshore platform consists of a half bridge connected in series to balance the voltage between the units and to collect the voltage in order to get the desired DC voltage. In the second topology, each unit contains a PMSG connected to 3-phase/3-phase matrix converter (MC) to control the generator speed by using a MPPT control. The offshore platform consists of a three phase High Frequency Transformer (HFT); the primary of each phase of the transformer connected to one phase from each unit. The secondary of the transformer connected to three phase diode bridge rectifier to get HVDC. The HVDC cable is used to transfer power from the offshore side to the onshore side. A Modular Multilevel Converter (MMC) is used in the onshore side to convert the voltage from DC to AC voltage and to integrate the offshore wind farm into the Grid.

This paper presents the control of a three level back to back converter with Permanent Magnet Synchronous Machine (PMSM). Field Oriented Control (FOC) is used to control the speed and the current of PMSM. Space Vector Pulse Width Modulation (SVPWM) is used to control the Three Level Rectifier and the Three Level Voltage Source Inverter. The simulation tests of the system have been developed based on Simulink/Matlab.