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This paper presents a non‐isolated single‐switch ultra‐high step‐up (UHSU) DC–DC converter with a three‐winding coupled inductor (CI) which is utilized to achieve ultra‐high voltage gain with a small amount of duty cycle leading to low conduction losses of the power switch and higher efficiency. The voltage gain of the suggested UHSU converter is adjusted by two methods: the duty cycle of the power switch and the three‐winding CI turn ratio, therefore enhancing the design flexibility of the suggested converter. Due to the utilization of the passive clamp circuit in the structure of the proposed converter, it is possible to select a power switch with low voltage rated and small ON‐state resistance, further enhancing the converter efficiency. The operation modes are discussed in detail and to clarify the salient features of the proposed converter, a comparison with other configurations is provided. Finally, to accredit the performance of the proposed converter, a 150‐W laboratory archetype with an input and output voltage of 20 and 300 V, respectively, at 50 kHz switching frequency is fabricated. [ABSTRACT FROM AUTHOR]

Effective fault detection, classification, and localization are vital for smart grid self-healing and fault mitigation. Deep learning has the capability to autonomously extract fault characteristics and discern fault categories from the three-phase raw of voltage and current signals. With the rise of distributed generators, conventional relaying devices face challenges in managing dynamic fault currents. Various deep neural network algorithms have been proposed for fault detection, classification, and location. This study introduces innovative fault detection methods using Artificial Neural Networks (ANNs) and one-dimension Convolution Neural Networks (1D-CNNs). Leveraging sensor data such as voltage and current measurements, our approach outperforms contemporary methods in terms of accuracy and efficiency. Results in the IEEE 6-bus system showcase impressive accuracy rates: 99.99%, 99.98% for identifying faulty lines, 99.75%, 99.99% for fault classification, and 98.25%, 96.85% for fault location for ANN and 1D-CNN, respectively. Deep learning emerges as a promising tool for enhancing fault detection and classification within smart grids, offering significant performance improvements. [ABSTRACT FROM AUTHOR]

This project proposes an improved hybrid solar and wind with battery management system with specialized and accurate controllers developed using PID controller, the main concern of the project is developing an intelligent system which will work in synchronization with all other components of microgrid. The algorithm is developed in such a way that all sources should operate according to the variable load conditions. [1]We have proposed algorithm which is efficient in terms of making system reliable and stable, we have involved renewable resources as solar and wind energy for generation thus saving fuel consumption ultimately it affects economy of country. Simulation has been done which demonstrate the whole scenario of operation of all components of microgrid. Simulation model consists of model of renewable sources and battery with its controller grid and Load. To test the effectiveness of the system it is simulated on MATLAB. We can analyze the system effectiveness at different conditions namely as step changes in irradiance and several load condition. [ABSTRACT FROM AUTHOR]

Modern distribution systems are equipped with various distributed energy resources (DERs) because of the importance of local generation. These distribution systems encounter more and more uncertainties because of the ever-increasing use of renewable energies. Other sources of uncertainty, such as load variation and system components' failure, will intensify the unpredictable nature of modern distribution systems. Integrating energy storage systems into distribution grids can play a role as a flexible bidirectional source to accommodate issues from constantly varying loads and renewable resources. The overall functionality of these modern distribution systems is enhanced using communication and computational abilities in smart grid frameworks. Robust operation of these systems is effectively taken into consideration to manage the uncertainty, which offers an explicit way to control the desired conservativeness. This paper presents an optimal operating program for smart grids equipped with wind generators, controllable distributed generators, energy storage systems, and reactive power compensators. In order to make the studies more practical, uncertainty about wind generators and grid loads is taken into account. Furthermore, the presented operating program is robust in various conditions, i.e. there is no need to change the operating program in a wide range of probable states. The point estimation method and fuzzy clustering method are used for probabilistic assessment of the distribution system in the presence of uncertainties. The IEEE 37-node standard test system, which is a highly unbalanced system, is selected for the case study and the results are discussed comprehensively. [ABSTRACT FROM AUTHOR]

The output power of a PV array is dependent on environmental factors such as solar irradiation and temperature. So, it has a non-linear I-V characteristic. Maximum Power Point (MPP) is a point on the I-V, P-V characteristic curve of a PV array where the PV device generates maximum output power. The location of MPP shifts as the climate changes. MPPT's aim is to keep the solar operating voltage as similar to MPP as possible under changing environmental conditions. They must run at their MPPT considering the inhomogeneous shift in environmental conditions in order to continuously gather the full power from the PV array. Here the most commonly used MPPT algorithms for PV applications are illustrated because they are easy to implement which are Perturb and Observe (P&O), Hill Climbing (HC) and Incremental Conductance (INC). In this paper, the applications of those three MPPT algorithms in PV systems at linear and nonlinear loads have been investigated. Comparative analysis has been done and the efficient one based on different testing scenarios has been determined based on output results. [ABSTRACT FROM AUTHOR]

In this paper, a novel AC-DC converter having dual stage voltage rectifiers and voltage summation architecture is designed. Voltages of the two DC-buses are added together at the output port via down-stream DC-DC transformers (DCXs). The DC output voltage is controlled by regulating the voltage of the adjustable DC-busses of the DV-rectifiers. Therefore, voltage regulation is not required for the DCXs, which can always operate at their highest operation point to guarantee maximum efficiency. As the voltage of the adjustable DC-buses are changeable, multilevel voltages can be obtained with the DVrectifier, which is benefit for reduction of switching losses and improvement of conversion efficiency. To achieve current regulation of AC input port and voltage regulation of the two DC-buses simultaneously, multi-mode operation and smooth mode transition strategies are proposed for the DV-rectifier. Operation principles, control strategies and characteristics of the DV-rectifier and DCX-based AC-DC converter are analyzed in detail. Feasibility and effectiveness of the proposed solutions are verified with experimental results. [ABSTRACT FROM AUTHOR]

In this paper, a new structure for a nonisolated boost dc–dc converter is proposed. The proposed converter generates higher voltage gain than some conventional nonisolated boost dc–dc converters. In this paper, the voltage and current equations of the elements and voltage gain in continuous conduction mode and discontinuous conduction mode are extracted. Then, the critical inductance converter is extracted and the current stresses in the switches are calculated. To achieve high voltage gain, a generalized structure based on the proposed structure generates for dc–dc converters. Meanwhile, the root mean square current relations of devices are obtained for an extended structure. Finally, the results of PSCAD/EMTDC software and laboratory prototype are used to reconfirm theoretical concept. [ABSTRACT FROM AUTHOR]

Mobile robot path planning is an important branch of research in robotics science. in this paper, a new approach for solving mobile robot path planning in dynamic environments, based on the Swarm Intelligence Algorithms feature of an optimized ABC algorithm is proposed. The proposed ABC will optimize the fuzzy rules' parameters that have been used for On-line path planning in dynamic environments. In this study, there is a proposed evaluation function, accordingly, the found path is smoother and cleaner than the previous studies using other algorithms. In this research, the ABC and ACO are combined with fuzzy logic; two algorithms are compared with each other. The performance of both combined algorithms in the execution speed and the number of occurrences for obtaining the optimal path in various unknown environments have been evaluated using MATLAB simulation methods. The obtained results from the comparison of the performance of these two algorithms developed optimization algorithms for mobile robots' path planning. [ABSTRACT FROM AUTHOR]

In this paper, a new structure of nonisolated boost dc–dc converters based on voltage-lift technique is proposed. In comparison with conventional nonisolated boost dc–dc converters, the proposed converter generates higher voltage gain. In this paper, the relations between voltage and current of all elements in continuous conduction mode and discontinuous conduction mode are calculated as well as voltage gain in each mode. Then, the critical inductance and stress of switch current are extracted. Finally, the validity of given theories is examined by using the experimental results. [ABSTRACT FROM PUBLISHER]

In this study, a new structure is proposed for non-isolated boost dc-dc converters using voltage-lift technique. The increasing voltage gain in the proposed converter is achieved step-to-step by a simple structure. In the proposed converter, there is a direct connection to an inductor in input side which provides free current ripple for the input source. Here, the proposed converter performance analysis and their relations are presented in continuous conduction mode and discontinuous conduction mode as well as voltage gain equations for each mode in detail. Then, switching current stress equations in each mode and critical inductance equations are extracted for design considerations. Finally, the carried theoretical analysis and satisfying operation of the proposed converter are verified via experimental results of laboratory prototype. [ABSTRACT FROM AUTHOR]

In this paper, a new structure of nonisolated boost DC-DC converters is proposed. The operation of the proposed structure in continuous conduction mode (CCM) and discontinuous conduction mode (DCM) is presented. Then, the critical inductance relation between CCM and DCM is obtained. The voltage gain and current stress of switches are calculated. Finally, the validity of the presented theoretical issues is reconfirmed by using simulation results obtained from PSCAD/EMTDC software. [ABSTRACT FROM AUTHOR]

Multilevel converters have received more attention recently. Multilevel converters can be used not only in high-voltage high-power applications, but also in energy storage systems, thanks to reduced harmonics and electromagnetic interferences. State-of-charge (SoC) balancing of the storage system cells within cascaded multilevel inverters, e.g., batteries, can be one of the challenges in practical applications. Different methods have been studied and reported in technical literature. However, the SoC balancing is still a challenging issue. In this paper, a new method is proposed to solve this problem by applying several clever but simple changes to the staircase modulation switching scheme without changing the output waveform properties. Validations for this simple method were performed through simulation and experimental prototype. Despite the simplicity of the method, the simulation and experimental results show that SoC balancing of the cells has significantly improved. [ABSTRACT FROM PUBLISHER]

The subsynchronous resonance (SSR) phenomenon may occur when a steam turbine-generator is connected to a long transmission line with series compensation. Flexible AC transmission systems (FACTS) devices are widely applied to damp the SSR and low-frequency oscillation (LFO). A thyristor-controlled series capacitor (TCSC) is a commercially available FACTS device that was developed for damping the SSR and LFO. In this paper, 2 control methods for damping the SSR and LFO are added to the TCSC main controller in order to demonstrate that the SSR damping capability of the TCSC can be enhanced by proper modulation of the firing angle. The control methods are presented, namely the conventional damping controller (CDC) and fuzzy logic damping controller (FLDC). The particle swarm optimization (PSO) algorithm is used for searching optimized parameters of the CDC. Fast Fourier transform is carried out in order to evaluate the effect of the TCSC-based FLDC in damping the SSR and LFO. The study system was adopted from the IEEE second benchmark model by altering a part of the fixed series capacitor to the TCSC. The MATLAB/Simulink was used to verify the effectiveness of each control method. The simulation results show that the FLDC has an excellent ability in damping the SSR and LFO in the power system toward the CDC-optimized PSO algorithm. [ABSTRACT FROM AUTHOR]

This paper discusses the operation of a distribution static compensator (D-STATCOM) based on three leg voltage source converter (VSC) in three. Phase four wire distribution systems. This device causes power quality improvement under unbalanced load, and regulates voltage when an induction Motor in system starts up. The proposed controller of D-STATCOM mitigates the neutral current and compensates harmonics current, reactive power, and balances the system. The insulated gate bipolar transistor (IGBT) based VSC is supported by a capacitor and is controlled for the required compensation of the load current. The performance of the three phase four wire D-STATCOM simulated in PSCAD/EMTDC soft ware. [ABSTRACT FROM AUTHOR]