IRANIAN JOURNAL OF ELECTRICAL AND ELECTRONIC ENGINEERING

Design of a Novel Barrier-Well Asymmetric Spacer Layer Tunnel Diodes for Implantable Rectenna Circuits

Shamil H. Hussein

This work presents an analysis and design of the two barrier-quantum well asymmetric spacer tunnel layer (QW-ASPAT) diodes for implantable rectenna circuits application. The RF and DC characteristic of a 10×10μm² QW-ASPAT devices based on GaAs and In_0.53Ga_0.47As platform was simulated and extracted by using SILVACO atlas software. The highest extracted curvature coefficient, k_v value of the both QW-ASPAT devices at zero bias was about 33V^-1 compared with the standard structure GaAs/InGaAs was about 13V^-1. The effects of changing in the thickness of the thin AlAs-barrier, the well width, and the spacer layer are fully investigated on the non-linear relationship between current and voltage of these diodes. A CV simulation was carried out, and it was found that the addition of the quantum-well layer between spacers and barrier reduced the junction capacitance of the QW-ASPAT device when compared with standard devices. The cut-off frequency of the proposed QW-GaAs and QW-InGaAs devices are 26GHz and 46GHz respectively. Finally, we conclude that the QW-ASPAT device is the best structure and can be used for microwave rectifiers in the miniaturized integrated rectenna systems.

Design and Implementation of a 31-level Inverter Based on FPGA for Sustainable Energy Applications

Rakan Khalil Antar

Artificial intelligence-based optimization algorithm was used to compute the switching angle values. In order to run the inverter with the lowest possible Total Harmonic Distortion (THD) value, it is suggested in this study to use an algorithm such as the Practical Swarm Algorithm (PSA). The multilevel inverter and optimization algorithm were created and simulated in this study using a MATLAB software. A frequency spectrum analysis was also conducted and found to be consistent with the theoretical analysis of the system. To provide practical results, the FPGA generates PWM signals that are appropriate for the inverter switches. On the Spartan-3E Starter set, the suggested control schemes were developed and put it into practice. Xilinx-ISE 12.1i design software and VHDL hardware description language were used to create the FPGA software. The suggested approaches have a number of benefits over conventional digital PWM techniques, including straightforward hardware implementation, minimum scaling of digital circuits, easy digital design, reconfigurable, and flexibility in adaptability. The outcomes of the experiment and the simulation agreed rather well.

Multivariable Prediction Control for Direct Vector Control of a DFIG-based Wind Turbine using a Fuzzy Space Vector Modulation Converter

azzedine khati

In this research paper, a multivariable prediction control method based on direct vector control is applied to command the active power and reactive power of a doubly-fed induction generator used into a wind turbine system. To obtain high energy performance, the space vector modulation inverter based on fuzzy logic technique (fuzzy space vector modulation) is used to reduce stator currents harmonics and active power and reactive power ripples. Also the direct vector control model of the doubly-fed induction generator is required to ensure a decoupled control. Then its classic proportional integral regulators are replaced by the multivariable prediction controller in order to adjust the active and reactive power. So, in this work, we implement a new method of control for the doubly-fed induction generator energy. This method is carried out for the first time by combining the MPC strategy with artificial intelligence represented by Fuzzy SVM-based converter in order to overcome the drawbacks of other controllers used in renewable energies. The given simulation results using Matlab software show a good performance of the used strategy, particularly with regard to the quality of the energy supplied.

A High Voltage Gain DC-DC Converter Based on Quadratic Boost Converter Suitable for Renewable Energy Resources

Saeed Hasanzadeh

Various forms of distributed generation (DG), such as photovoltaic (PV) systems, play a crucial role in advancing a more sustainable future, driven by economic factors and environmental policies implemented by governments. DC-DC converters are essential for harnessing power from solar cells, as they maintain a constant output voltage despite fluctuations in input voltage. Typically, step-up converters are employed to raise output voltage levels, though they often apply the same voltage to an active switch as the output voltage, which can be limiting. To effectively integrate distributed generation sources with the utility grid, high-voltage gain step-up converters are necessary since these sources typically operate at low voltage levels. This study presents an enhanced design of non-isolated DC-DC converters with high voltage gain tailored for photovoltaic (PV) applications. The proposed architecture achieves a quadratic increase in output voltage gain, which alleviates voltage stress on the active switch. Our converter design features a quadratic boost converter complemented by a voltage-boosting cell, facilitating significant voltage amplification. This topology benefits from employing an active switch while minimizing the number of inductors required, resulting in a more compact circuit design. Furthermore, the proposed architecture shares characteristics with recently published topologies regarding passive component utilization, voltage gain, and other relevant parameters. To validate our findings, we conducted mathematical analyses and simulations, with results corroborated by experimental data from laboratory prototype tests.

Performance Comparison of Hybrid Switch, Phase Shifter and Lens Network over Hybrid Beamforming in Millimeter Wave Massive MIMO

Tadele A Abose

Due to cost and energy concerns with digital beamformers, much of the beamforming is done by hybrid beamformers in mm-wave (mm) massive multiple input multiple output (MIMO). Various works in hybrid beamforming structures considered either phase shifters, switches, or radio frequency lenses individually as switching mechanisms between antennas and precoding systems. Works that consider the hybrid use of phase shifters, switches, and radio frequency lenses need further investigation since there is a tradeoff between cost and system performance in each switching mechanism. The main aim of this research is to analyze the performance of a hybrid switch, a 1-bit phase shifter, and radio frequency (RF)-Lens in a hybrid beamforming network as a switching network. Simulation results showed that the hybrid of three has a spectral efficiency (SE) performance of 59.04 bps/Hz, which increases by 6.9 bps/Hz from that of the switch and lens antenna array network. The energy efficiency (EE) of the switch, phase shifter, and lens showed a performance of 46.41 bps/Hz/W, while the switch and lens antenna array, phase shifter, and lens antenna array showed a performance of 48.52 bps/Hz/W. The result also shows that the hybrid network achieves optimum performance at the expense of higher computational complexity.

Enhancement of Distribution Transformer Lifespan by using Distributed Generation under Transactive Control Rescheduling

Akanksha Jain

Due to the anticipated increase in loads, the power grid will encounter the issue of system peak loads in the future, which is typically addressed through grid reinforcement. However, implementing a flexibility service option can prevent the need for grid development. As the overall load continues to rise, the distribution transformer becomes overloaded. The presented work focuses on enhancing one of the parameters that define the insulation life of the transformer, known as the Loss-of-Life (LOL). Transactive approach involves the rescheduling of the battery and photovoltaic generation. Dominated Group Search Optimization (DGSO) algorithm is utilized to optimize the objective function of reducing the peak transformer load under the power flow and voltage constraints of the network. Experimental validation of the proposed method is conducted using MATLAB 2018 software. Modified IEEE 34-bus system is used to implement the proposed methodology. Numerical results obtained from various cases elucidate that the proposed model reduces the LOL of the transformer from 0.0103 to 0.0017 p.u.Comparative analysis of the proposed method with the already used methods of voltage-control and Volt-Var control have been presented.

Millimeter Wave Energy Absorption by Human Tissues: Evaluation of Tissue Penetration

Sulaiman Adeniyi Adekola

Presented in this paper is an evaluation of human tissue penetration by millimeter wave (mmW) energy, particularly at 30, 35, 40 and 45 GHz. Numerical simulations show that the penetration depths in the tissue are (0.1000, 0.0937, 0.08869 and 0.08882) mm at the aforementioned frequency, respectively. It is also demonstrated that all mmW at those frequencies attenuate to zero at the epidermis which is the layer adjacent to the skin surface, without getting into the dermis which is the next layer. Crucially, these discoveries present fresh, previously unmentioned data within the current research literature. Furthermore, at the lower frequency of 24 GHz, computer simulations presented show that the propagating wave penetrates deeper (depth of 0.12 mm) and attenuates to zero at the dermis. This shows that the depth of penetration increases further at lower frequencies which strongly conforms to the principles of physical reasoning, thereby bolstering the reliability of the findings presented in this paper. The results collectively indicate that the absorption of mmW into the human tissue have limited significance when assessing compliance with electromagnetic field standards at mmW frequencies. It is reinforced in this paper why the human skin reduces the harmful effects of ultra-violet radiation. To lend credence to our formulation, certain aspects of the results obtained in this investigation when compared with similar results in the literature, show good agreements.

Optimal Reconfiguration using Firefly Algorithm for Integrated Electrical Distribution Network with Distributed Generation, Case Study: 20 kV Tarahan Substation, Province of Bandar Lampung, Indonesia

Imam Robandi

The unbalanced load distribution in the electrical distribution network caused crucial power losses. This condition occurs in one of the electrical distribution networks, 20 kV Tarahan Substation, Province of Bandar Lampung, Indonesia. This condition can be maintained using optimal reconfiguration with the integration of Distributed Generation (DG) based on Renewable Energy (RE). This study demonstrates the optimal reconfiguration of the 20 kV Tarahan Substation with the integration of the Photovoltaic (PV) and Battery Energy Storage System (BESS). The reconfiguration process is optimized by using the Firefly Algorithm (FA). This process is conducted in the 24-hour simulation with various load profiles. The optimal reconfiguration is investigated in two scenarios based on without and with DG integration. The optimal configuration with more balanced load distribution conducted by FA reduces the power losses by up to 31.39% and 32.38% in without and with DG integration, respectively. Besides that, the DG integration improves the lowest voltage bus in the electrical distribution network from 0.95 p.u to 0.97 p.u.

A Novel Meta-Heuristic Optimization Algorithm to Determine Optimal Access Point and Generation of Distributed Generators for Maximizing Economic and Technical Benefits

Nguyen Cong Chinh

This paper presents an intelligent meta-heuristic algorithm, named improved equilibrium optimizer (IEO), for addressing the optimization problem of multi-objective simultaneous integration of distributed generators at unity and optimal power factor in a distribution system. The main objective of this research is to consider the multi-objective function for minimizing total power loss, improving voltage deviation, and reducing integrated system operating costs with strict technical constraints. An improved equilibrium optimizer is an enhanced version of the equilibrium optimizer that can provide better performance, stability, and convergence characteristics than the original algorithm. For evaluating the effectiveness of the suggested method, the IEEE 69-bus radial distribution system is chosen as a test system, and simulation results from this method are also compared fairly with many previously existing methods for the same targets and constraints. Thanks to its ability to intelligently expand the search space and avoid local traps, the suggested method has become a robust stochastic optimization method in tackling complex optimization tasks.

Design and implementation of Mobile Robot for Fire Fighting Using Photovoltaic Panel with Artificial Intelligent

Raheel Jawad

Fire accidents are a disaster that can cause loss of life, property damage and permanent disability to the affected victim. Firefighting is a very important and dangerous job. Firefighters must extinguish the fire quickly and safely to prevent further damage and destruction. Detecting and extinguishing fires is a dangerous task that always puts the lives of firefighters at risk. One of the most effective tools for early fire extinguishing is the firefighting robot. Fire sensing in most industries is absolutely essential to prevent catastrophic losses. Robots with this type of embedded system can save the lives of engineers in industrial sites with hazardous conditions. This project aims to design and implement a solar-powered with artificial intelligent of mobile fire detection robot to detect fires in disaster-prone areas and thus reduce human work effort and level of destruction. Design a robot capable of moving using a rotary motor, finding a flame using a flame sensor, and extinguishing a fire using a water spray using a pump, all of which is controlled by an Arduino Uno microcontroller and programmed using an artificial intelligence (fuzzy) logic technology) using MATLAB, the inputs It has two variations:: flame and gas with three organic functions, each of which has a gas variable (low, medium, high), flame sensor (small, normal, large), and the output is a pump, (pump off , pump on ) with 9 rules. In addition to the experimental setup of the proposed system which demonstrates the performance of sensors (gas, flame) using fuzzy and implemented logic tools. The performance of the solar panels was first tested using MATLAB software as well as experimentally under different weather conditions. The pump's performance is being tested experimentally, and the robot is also being tested to detect and extinguish fires. The process of designing and implementing robotics involves creating mechanical and electrical systems. The results showed the effect of temperature change on the solar panel, as when it increases, the panel’s production capacity decreases, as well as the effect of decreased solar radiation resulting from clouds and other things, and the extent of its effect. Impact on the performance efficiency of solar panels, and observing the pump performance in terms of flow rate and height. Hence, it can be noted that the robot designed in the project is capable of discovering fire sources and extinguishing them using fire-fighting systems equipped with a water tank and a controllable pump to spray the water necessary for the process. From this study, can be concluded that the designed model is able to work according to its initial design with artificial intelligence with the least amount of errors, and therefore it can be applied in industrial applications, avoiding fire damage and extinguishing it when it occurs for the first time.

BiliBin: An Intelligent Mobile Phone-based Platform to Monitor Newborn Jaundice

Eisa Zarepour

Using mobile phones for medical applications are proliferating due to high-quality embedded sensors. Jaundice, a yellow discoloration of the skin caused by excess bilirubin, is a prevalent physiological problem in newborns. While moderate amounts of bilirubin are safe in healthy newborns, extreme levels are fatal and cause devastating and irreversible brain damage. Accurate tests to measure jaundice require a blood draw or dedicated clinical devices facing difficulty where clinical technology is unavailable. This paper presents a smartphone-based screening tool to detect neonatal hyperbilirubinemia caused by the high bilirubin production rate. A machine learning regression model is trained on a pretty large dataset of images, including 446 samples, taken from newborns' sternum skin in four medical centers in Iran. The learned model is then used to estimate the level of bilirubin. Experimental results show a mean absolute error of 1.807 mg/dl and a correlation of 0.701 between predicted bilirubin by the proposed method and the TSB values as ground truth.

Wideband Electromagnetic Shielding Using Wire-mesh-mounted Chiral Particle Array in Concrete Composite Materials

Ahmad Cheldavi

This paper proposes a structure for concrete composite materials that effectively attenuates transmitted power through the composite slab across a wide frequency range. The proposed structure is practical for electromagnetic interference shielding applications. To assess its effectiveness, the proposed structure has been compared with two other structures: a traditional wire mesh used in reinforced composites and an array of helices, a cutting-edge technique for manufacturing lightweight concretes with significant improvements in shielding properties. The comparison among full-wave simulation results indicates that the proposed method leverages the benefits of both techniques. It achieves a shielding effectiveness exceeding 30 dB from low frequencies up to 8.5 GHz and beyond 55 dB from low frequencies up to 4 GHz. Furthermore, an experimental measurement was conducted to validate the full-wave simulation results. An experimental sample was fabricated according to the simulated proposed structure, and the measured shielding effectiveness confirmed the composite's capability in wideband electromagnetic shielding. Theoretically, the proposed structure can enhance the concrete's mechanical characteristics while improving its shielding effectiveness, making it suitable for designing ultra-high-performance concretes.