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Ships condition is assessed regularly to maintain safety. Traditionally, structural integrity assessment is performed by surveyors, requiring complex and time-consuming operations to accessany ship...

Clinical diagnosis has increased marvelous significance in current day healthcare systems. This article proposes a brain tumor detection method using edge detection based fuzzy logic and U-NET Convolutional Neural Network (CNN) classification method. The proposed tumor segmentation system is based on image enhancement, fuzzy logic based edge detection, and classification. The input images are pre-processed using the contrast enhancement and fuzzy logic-based edge detection method is applied to identify the edge in the source images and dual tree-complex wavelet transform (DTCWT) is used at different scale levels. The features are calculated from the decayed sub-band images and these features are then categorized using U-NET CNN classification which recognizes the meningioma and non-meningioma brain images. The proposed method is evaluated using accuracy, sensitivity, specificity, and dice coefficient index. Simulation study demonstrates that the proposed technique achieves better performance, both visually and quantitatively in comparison with other approaches.

All civil infrastructure units demand regular inspection to avoid functional and structural damages. Periodic examinations are in accordance with classification society’s standards which contain both non-destructive tests and visual surveys, to search structural damage, reliability, cracks, thickness measurement, and Water dripping generally documented by manually or with measurements tape. But, it is very hard to search cracks by visually monitoring much larger structures. Hence, the advent of crack detecting and monitoring systems has been a major issue. In this proposed study a crack detection algorithm in reference to digital image processing technology is suggested. Obtaining information of a surface crack by using an image pre-processing pipeline and to estimate the failure is proposed which helps and detects the structure cracks and body health information. It provides the identification system more portable and integrated, estimates the crack more precisely and reduction in expenditure as well. The proposed algorithm accuracy is 93.8% as compared to the traditional and recent work.

A control topology input-parallel–output-series converter system is investigated, which is suitable for high-voltage and high-output power applications. In this control method input current sharing (ICS) and output current sharing (OVS) taken into account. As observed, ICS is automatically attained as OVS sharing is controlled. In this design, two modules are connected in series, Module 1 provided variable voltage but in Module 2 by using three-level neutral-point-clamped converter and designing a comprehensive control feedback system, which regulates the DC voltages at the constant magnitude and constant frequency, helps to provide constant output voltages in the event of uncertain disturbance and load variation, A feedback double closed-loop control topology (inner current loop control and outer voltage loop control) with the combination of sliding mode control and a proportional–integral control method. A simulation model is built, by using MATLAB/Simulink, and the simulation results show excellent performance and feasibility of this system. This will be beneficial for research and improvement for the grid-connected converter.

In this paper economic dispatch problem (EDP) of a micro-grid structure is studied using distributed consensus algorithm based on graph theory. In a power system economic dispatch ensures the optimal power utilization by finding an identical value of incremental cost for each bus. So, the incremental cost is adopted as a consensus term while using local information of mismatch between active power generation and total load demand as feedback in order to solve EDP in this paper. The proposed scheme is fully distributed and requires no leader or central control for achieving consensus. Various cases are used to study the effectiveness of proposed scheme. Simulation results conclude that incremental cost converges to its optimal value whether load demand is varying or generators plug-and-play.

With increasing demand of energy, air pollution is on rising. To mitigate this issue, combined production of cooling, heat, and power (CCHP) system getting worldwide attention due to its effectiveness. A case study recommends that CCHP system should be run under the optimal scheme. This paper focuses on the optimal scheduling and analysis of CCHP system in comparison to the separate production of cooling, heat, and power (SPCHP) system. In this article, two different model designs are proposed to ensure electric, cooling and heating loads in summer and winter to maximize the energy saving by reducing the total cost and carbon dioxide emission. An interior point (IP) based algorithm is designed in Matlab for optimal energy flow. The IP is a fascinating method because of its convergence time, robustness, ease of handling the inequality constraints and few numbers of iterations to the optimum power flow problems. Furthermore, the analysis is performed in order to exhibit how the economic, energetic and environmental behavior of CCHP system changes under different conditions as compared to separate production of cooling, heat, and power (SPCHP) system. Finally, results show that overall performance of CCHP system is better than SPCHP systems.

The current relocation of AC to DC loads, and DC power generations for renewables, Medium voltage DC (MVDC) will fill the gap in the field of distribution, transmission and enhance the efficiency of Existing systems. DC converters are the growing technology for interconnection the upcoming DC-grids, providing controllability, stability, and bidirectional power flow. In this proposed study a novel and effective control strategy for 3ϕ VSR (voltage source PWM rectifier), a double-closed-loop control strategy, the outer voltage control loop and inner current loop is proposed, based on rotating synchronous coordinates and comprehensive mathematical model is designed, In the internal current loop a hybrid control practical method which consist of a (IMC) internal mode control and internal decoupling, which performed the complete decoupling and reduces the tuning constraints of the designed controller, and the outside voltage loop is linear. In this control topology the conditions of loads disturbance, fluctuations and voltage dip have been taken into consideration. By using Matlab/Simulink the results shows the effectiveness and robustness of the suggested control system.

This paper presents a consensus based solution for multi-objective economic dispatch (ED) of a distributed power network. In the recent years with involvement of renewable energy, microgirds and distributed generators (DG’s), the conventional power system is becoming more and more distributed and clean. Therefore, distributed methods for solving ED problem are gaining more importance. The problem in a distributed network is to satisfy the power balance constraint in a environment friendly way using consensus algorithm. As, in the distributed network it is hard to get power mismatch without a central controller. This paper presents a frequency control method combined with graph theory based consensus protocol to satisfy the power balance constraint. Two different types of control strategies are adopted, first PID based controller is used and then Neural Network (NN) based controller. Line losses are also integrated with the consensus protocol. Simulation results are validated for load variations and line losses model in the final section.

In this study a control strategy of two-level Three-phase grid connected PV system by using SVPWM method is proposed for distribution and generation system. Traditional grid rectifier brings a lots of harmonics pollution, to decrease these harmonics, in this control system technique a double closed loop control based on. (ISMC). Integral. Sliding. Mode. Control. internal current loop and voltage control external loop is presented. The main objective of this controller is, low error (SS) steady state, enhanced voltage regulation, unity power factor, little (THD) total harmonic pollution distortion and small disturbance taken into consideration. By using Matlab/Simulink software simulation results shows the proposed control system is effective, good dynamics and fast response which open new insights in distribution systems

Distributed power and smart grids play a crucial role in the upcoming future power grid system. Sooner, many DC grids will coincide with traditional common AC grids. This study investigate and presents a control scheme for three phase (VSR) Voltage source PWM rectifier among the combination of (SMC) sliding mode control and (PI) proportional integral technique. A control strategy of double closed control system is proposed which consist of inner current loop (SMC) and outside voltage (liner control) loop. During the designing of controller, the conditions of load disturbance, unity P.F under load variation and output DC voltage controlled etc. taken into attention. The simulation results show the effectiveness, feasibility of this system and good dynamics performance of the suggested control system. Which is beneficial for research and development for grid-connected converters.

Power electronics switching devices involving Wide Band Gap (WBG) materials such as, silicon carbide (SiC) and gallium nitride (GaN) provide substantial switching level improvements as compared to the silicon (Si) devices. Their ability to operate at higher voltages, temperatures and frequencies make them highly eligible for use in the future power electronics. In order to provide a comparative analysis of these materials, we studied their various parameters like energy band gap, carrier mobility, saturation velocity and thermal conductivity. A study also has been conducted to analyze and evaluate performance of GaN FET, SiC JFET and Si IGBT based dc-dc buck boost converter. Switching performance and energy dissipation at a variable junction temperature range is compared and evaluated for three power devices. Transistors' switching and conduction losses and their temperature dependency is discussed at the end. The results show that GaN based converter has better switching performance and overall efficiency, but have strong dependency of temperature.

Harnessing wind energy is the most rapidly growing amongst the renewable energy sources. However, because of its intermittency nature, wind power results in unfavorable influences on power system operations and stability. The voltage flicker and grid frequency fluctuation are significant in this regard. To minimize the effect of wind power fluctuations on the grid frequency and AC bus voltage, this paper presents direct power control strategy-based variable speed pumped storage system. Modeling of the system is undertaken based on phasor model technique. The case study is made by considering conventional synchronous machines for hydropower and thermal power plans in the grid and induction machines for the VSPS and wind turbines. The performance is analyzed using MATLAB/Simulink platform. The results show that the proposed VSPS control strategy achieves well-regulated and stable grid frequency and AC voltage in the power system.