20 research outputs found
Design and analysis of a brushless three phase flux switching generator for aircraft auxiliary power unit
This paper introduces a design of a three-phase flux switching machine (FSM), which is mainly designed for a 400 HZ aircraft auxiliary power unit. In this design, there are two winding sets embedded in the stator slots. One, is referred to as three phase armature windings, supply the power to the aircraft electrical system. The other winding, namely excitation winding, is fed from a dc supply. Also, a slotted rotor will be designed without any winding or permanent magnets. Moving the field winding to the stator not only ensures brushless construction, but also reduces generator weight through the direct coupling between the generator and the gas turbine. The machine is initially simulated using 2-D finite element analysis (FEA) and its performance is analyzed. Additionally, a prototype is implemented, and its performance is practically measured in order to prove the validity of the proposed machine for aircraft auxiliary power units
A Variable Speed Synchronous Motor Approach for Smart Irrigation using Doubly Fed Induction Motor
Department of Electrical Engineering, College of Engineering, Jazan University, Jizan 45142, Saudi Arabia.Doubly Fed Induction Motor (DFIM) is a popular machine used in variable speed drives, and its ruggedness, reliability and simplicity of speed control make it a suitable candidate for use in smart irrigation systems. This paper studies and evaluates the performance of DFIM at different operating conditions and shows that it can be viewed as a variable speed synchronous motor. The research results reveal that DFIM can be used to control the flow rate of water in irrigation systems, by adjusting the speed of the motor to match the desired flow rate. A mathematical model has been developed to optimize the performance of the DFIM in smart irrigation systems, taking into account the specific conditions of the application. In addition, an experimental setup was built and tested to enhance the theoretical results, which showed good correlation between the theoretical and experimental results. The results of this research demonstrate the potential of using the DFIM in smart irrigation systems to improve the performance and efficiency of irrigation and to provide better control and lower costs
Dr.
Department of Electrical Engineering, College of Engineering, Jazan University, Jizan 45142, Saudi Arabia
Analysis and Experimental Validation of Single-Phase Cascaded Boost AC–AC Converter with High Voltage Gain
This article presents a single-phase cascaded AC–AC converter with boosting capability for power-quality issues. A high voltage gain can be obtained based on the number of cascaded units. The basic construction of one unit in the cascaded connection requires only two four-quadrant switches with a low-voltage rating. The performance features for the topology are a unity power factor that is close to unity on the input side, high steady-state performance, and fast dynamic response. The operation modes and mathematical model for the topology are presented. An appropriate PI-based control method/strategy is created, so the converter may continue to run while attaining the desired voltage gain, even if one of the cascaded units fails. The control circuit’s ability to maintain the continuity of matching the input current waveform with the input voltage waveform allows a decrease in the THD with different operating conditions. Moreover, the ability to solve a dead time problem carried out by the control circuit leads to a reduction in voltage stress. The effectiveness and robustness of the proposed technique were demonstrated via a computer simulation using MATLAB/Simulink. Moreover, an experimental setup for the system was built in the laboratory to validate the practicability of the system, which was tested under different conditions. The good agreement obtained between the theoretical and experimental results endorses the validity of the designed circuit
Renewable Energy Resources Technologies and Life Cycle Assessment: Review
Moving towards RER has become imperative to achieve sustainable development goals (SDG). Renewable energy resources (RER) are characterized by uncertainty whereas, most of them are unpredictable and variable according to climatic conditions. This paper focuses on RER-based electrical power plants as a base to achieve two different goals, SDG7 (obtaining reasonably priced clean energy) and SDG13 (reducing climate change). These goals in turn would support other environmental, social, and economic SDG. This study is constructed based on two pillars which are technological developments and life cycle assessment (LCA) for wind, solar, biomass, and geothermal power plants. To support the study and achieve the main point, many essential topics are presented in brief such as fossil fuels’ environmental impact, economic sustainability linkage to RER, the current contribution of RER in energy consumption worldwide and barriers and environmental effects of RER under consideration. As a result, solar and wind energy lead the RER electricity market with major contributions of 27.7% and 26.92%, respectively, biomass and geothermal are still of negligible contributions at 4.68% and 0.5%, respectively, offshore HAWT dominated other WT techniques, silicon-based PV cells dominated other solar PV technologies with 27% efficiency, combustion thermochemical energy conversion process dominated other biomass energy systems techniques, due to many concerns geothermal energy system is not preferable. Many emerging technologies need to receive more public attention, intensive research, financial support, and governmental facilities including effective policies and data availability
Two-stage grid-connected inverter topology with high frequency link transformer for solar PV systems
This study introduces a new topology for a single-phase photovoltaic (PV) grid connection. This suggested topology comprises two cascaded stages linked by a high-frequency transformer. In the first stage, a new buck–boost inverter with one energy storage is implemented. The buck–boost inverter can convert the PV module’s output voltage to a high-frequency square wave (HFSWV) and can enhance maximum power point tracking (MPPT) even under large PV voltage variations. The high-frequency transformer gives galvanic isolation for the system, which decreases the leakage current and improves the system power quality. The second stage of the topology involves using a rectifier-inverter system to interface the produced HFSWV to the utility grid. The proposed system uses high switching frequency which increases the power density, reduces the grid filter size, and increases the system reliability. Buck–boost DC/AC inversion, MPPT and low grid current injection are implemented. The working principles of the proposed topology have been investigated, and the theoretical and experimental results are developed and analyzed
Active Power Filter with Reduced Number of Semiconductor Switches Based on Synchronous Reference Frame
Reactive Power Management Based Hybrid GAEO
Electrical power networks are expanded regularly to meet growing energy requirements. Reactive power dispatch (RPD) optimization is a powerful tool to enhance a system’s efficiency, reliability, and security. RPD optimization is classified as a non-linear and non-convex problem. In this paper, the RPD optimization problem is solved based on novel hybrid genetic algorithms—equilibrium optimizer (GAEO) optimization algorithms. The control variables are determined in such a way that optimizes RPD and minimizes power losses. The efficiency of the proposed optimization algorithms is compared to other techniques that have been used recently to solve the RPD problem. The proposed algorithm has been tested for optimization RPD for three test systems, IEEE14-bus, IEEE-30bus, and IEEE57-bus. The obtained results show the superiority of GAEO over other techniques for small test systems, IEEE14-bus and IEEE-30bus. GAEO shows good results for large system, IEEE 57-bus
Enhancing Photovoltaic Conversion Efficiency With Model Predictive Control-Based Sensor-Reduced Maximum Power Point Tracking in Modified SEPIC Converters
The objective of this paper is to propose a new technique for maximum power point tracking (MPPT) in photovoltaic (PV) systems that utilizes fewer sensors, thereby reducing the hardware cost. The technique aims to achieve efficient MPPT under various environmental conditions by employing a modified SEPIC converter and a model predictive control (MPC)-based MPPT algorithm. To achieve the objective, the proposed technique utilizes only one voltage sensor and one current sensor, significantly reducing the hardware requirements compared to traditional MPPT techniques. The modified SEPIC converter is employed to regulate the voltage and current levels in the PV system. The MPC-based MPPT algorithm is implemented to dynamically adjust the operation of the converter and track the maximum power point. The algorithm incorporates a model predictive control approach, which utilizes a predictive model of the PV system to anticipate and optimize the power output. The algorithm predicts the behavior of the PV system based on the available sensor measurements, allowing for accurate MPPT. The algorithm operates in real-time, providing instantaneous adjustments to maximize power extraction. The study demonstrates that the proposed technique effectively tracks the maximum power point of the PV system using only one voltage sensor and one current sensor, thus reducing the overall hardware cost. The MPC-based MPPT algorithm, in combination with the modified SEPIC converter, achieves efficient power extraction under various operating conditions. The simulation and experimental results indicate that the proposed technique outperforms traditional MPPT techniques in terms of cost-effectiveness and power extraction efficiency