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In order to improve power system stability and suppress low power oscillations, active power regulation using variable frequency transformer (VFT) plays an important role. The literature has already documented in‐depth research on active power transfer control principles of VFT. The VFT, which is basically a wound rotor induction machine consumes reactive power because of magnetizing winding. In terms of the power flow interchange in a two‐area power system incorporating VFT, this work gives an extensive analysis to comprehend the reactive power needs under various operating circumstances. In the context of reactive power compensation, the present study explores two distinct methodologies: the implementation of a fixed shunt capacitor and the utilization of an artificial neural network (ANN)‐based static synchronous compensator (STATCOM). The STATCOM‐based control technique outperforms the conventional fixed shunt capacitor by demonstrating improved capabilities in reducing reactive power imbalances and stabilizing the power system. Further, a control scheme based on voltage regulation is implemented for integrating the STATCOM to enhance the fault ride through capability of a three‐phase bus fault. Additionally, two‐area test system is exposed to a reactive load shift to evaluate the operation of STATCOM, which restores the bus voltage to its pre‐specified value. [ABSTRACT FROM AUTHOR]

Solar‐based Distributed Generation (DG) powered Electric Vehicles (EVs) charging stations are widely adopted nowadays in the power system networks. In this process, the distribution grid faces various challenges caused by intermittent solar irradiance, peak EVs load, while controlling the state of charge (SoC) of batteries during dis(charging) phenomena. In this paper, an intelligent energy management scheme (IEMS)‐based coordinated control for photovoltaic (PV)‐based EVs charging stations is proposed. The proposed IEMS optimizes the PV generation and grid power utilization for EV charging stations (EVCS) by analysing real‐time meteorological and load demand data. The coordinated control of EMS provides power flow between PV generation, distribution grid, and EVs battery storage in a manner which results in the reduction of peak power demand by a factor of two. Further, the adaptive neuro‐based fuzzy control approach includes forecasting solar‐based electricity generation and EVs loads demand predictions to optimize IEMS according to the Indian power scenario. The proposed IEMS optimally utilizes the buffer batteries system for reducing the peak electricity demand with low system losses and reducing the impact of EVs charging load on distribution grid. The results are analysed using the digital simulation model and validated with real‐time hardware‐in‐loop experimental setup. [ABSTRACT FROM AUTHOR]

Summary: Modern power systems face challenges with stability, especially due to interconnections through weak tie‐lines, which can lead to power oscillations. These oscillations occur when the rotor fails to provide sufficient damping force to balance electrical output and mechanical input. Without a reliable damping system, these oscillations can persist, posing a threat to power system stability. In this article, a novel solution is proposed to curb low‐frequency oscillations by implementing a new power transmission technology called variable frequency transformer (VFT) in a two‐area power system. The VFT is equipped with an industrially applied proportional integral derivative controller trained by an artificial neural network to regulate power flow between the two areas. Additionally, a power oscillation damping controller is introduced that utilizes intelligent tuning through salp swarm optimization to enhance the damping capabilities of the VFT. The intelligent tuning of the power oscillation damping controller using salp swarm optimization enhances the damping capabilities of the VFT, resulting in a 25% increase in the damping ratio. To evaluate the performance of the VFT‐based system, it has been compared with a well‐established high voltage direct current (HVDC) system through a three‐phase fault analysis and reactive power requirement. Quantitatively, the proposed VFT system achieves a significant improvement in damping power oscillations, reducing their amplitudes by 30% compared to the HVDC system. Furthermore, the system is linearized under specific operating conditions, and eigenvalue analysis is conducted to assess power system stability for both VFT and HVDC cases. Through time‐domain simulations and eigenvalue analysis, our findings demonstrate that the VFT system surpasses the HVDC system in various operational and control aspects, highlighting its positive impact on power system stability. [ABSTRACT FROM AUTHOR]

Traditionally, phase shifters powered by power electronics are used in conjunction with energy storage devices to improve the load frequency control. Conventional phase shifters provide minimal inertia and offer a significant threat to power quality due to harmonics. This study suggests the type‐2 fuzzy based adaptively predictive controlled variable frequency transformer (F2‐APC‐VFT) as a phase shifter to work in coordination with superconducting magnetic energy storage (SMES) for improved load frequency control. To assess the effectiveness of coordinated control, a two‐area, four‐machine linked power system with F2‐APC‐VFT installed in succession with the connecting line near to area one and SMES in the other area is employed. A type‐2 fuzzy controller is used to tune the cost function weights of the adaptive predictive controller (APC). A simulation study is conducted in MATLAB to show the effectiveness of the suggested strategy. Tuning the cost function weights with a type‐2 fuzzy controller considerably impacts in minimising the frequency and tie‐power deviations. The effectiveness of the F2‐APC is verified by comparing its performance with that of an adaptive neuro fuzzy inference system (ANFIS) controller and constant weight‐based adaptive predictive controller (C‐APC). [ABSTRACT FROM AUTHOR]

The multiphase matrix converter outperforms the conventional three-phase system with higher fault tolerance capability and higher power control competency. This paper discusses the direct control based on different possible switching combinations of a threephase to five-phase matrix converter (MC). The proposed control topology significantly reduces the switching commutations in a switching cycle when compared with its counterpart. The control is based on the modified space vector pulse width modulation (SVPWM) strategy. The proposed space vector scheme intelligently selects the voltage vectors to get the desired output characteristics with the least possible switching transitions in a switching cycle. Three possible cases exist in controlling space vectors based on their magnitude, the number of active switching vectors, and their commutations. The results for three different cases of SVPWM have been presented and compared. The total harmonic distortion (THD) obtained in the output is lower in case 2; however, it suffers from a higher commonmode voltage (CMV). The scheme has been successfully implemented and verified in hardware. [ABSTRACT FROM AUTHOR]

This paper implements Broyden's Method Assisted Differential Evolution (BMADE) algorithm for eliminating third and fifth harmonics in the output voltage of 7‐level cascaded H‐Bridge multilevel inverter (CHB‐MLI) using selective harmonic elimination technique. Calculations of switching angles are done for various modulation index values (M). Initial guess for Broyden's method is calculated by Differential Evolution (DE). Exact value of switching angles is then calculated by Broyden's method using initial guess obtained from DE. Code of BMADE algorithm for obtaining the required switching angles is written in MATLAB. Results obtained with BMADE algorithm are compared with various other techniques that is, Genetic Algorithm (GA), DE, and Whale Optimization Algorithm (WOA). BMADE is able to successfully eliminate third and fifth order harmonics in the output voltage. Along with removing the desired harmonics, BMADE also provides lower THD than GA, DE, and WOA for certain range of M. The results also showed that BMADE is faster than GA, DE, and WOA as the execution time of BMADE is lesser than GA, DE, and WOA. Moreover, laboratory experiments are used to test the simulation's findings. The experimental results support the simulation results. [ABSTRACT FROM AUTHOR]

The application of iterative techniques for solving the Selective Harmonic Elimination Pulse Width Modulation (SHE‐PWM) problem, such as the Newton–Raphson (NR) method, can tend to get stuck at local optima in the solution space. Additionally, these methods may be sensitive to the initial value estimation of the solution. In contrast, metaheuristic approaches demonstrate resilience in seeking out the optimal solution. As such, this study utilizes the Runge–Kutta (RUN) metaheuristic optimization algorithm to demonstrate the SHE‐PWM technique in multilevel inverters (MLIs), including 5‐ and 7‐level modified H‐bridge (MHB) topology and a 9‐level asymmetric cascaded H‐bridge (CHB) inverter topology. The switching angles are obtained by varying the modulation index from 0.01 to 1.0 in steps of 0.01 for 5‐, 7‐, and 9‐level MLIs. The performance of the RUN algorithm in minimizing the total harmonic distortion (THD) value is verified through simulations in MATLAB/Simulink software. The superiority of RUN is established by comparing the results with state‐of‐the‐art metaheuristic algorithms, such as the Differential Evolution (DE), Genetic Algorithm (GA), and Grey Wolf Optimizer (GWO). Additionally, the switching angles obtained through RUN are validated by hardware experiments. According to the simulation and experimental results, the proposed RUN method exhibits better performance in terms of objective function values, algorithm robustness, fundamental harmonic magnitude, and THD values. The findings confirm the elimination of fifth harmonic, fifth, and seventh harmonics, and fifth, seventh, and ninth harmonics in 5‐, 7‐, and 9‐level MLIs, respectively. [ABSTRACT FROM AUTHOR]

The presence of bypass diodes in photovoltaic (PV) arrays can mitigate the negative effects of partial shading conditions (PSCs), which can cause multiple peak characteristics at the output. However, conventional maximum power point tracking (MPPT) methods can develop errors and detect the local maximum power point (LMPP) instead of the global maximum power point (GMPP) under certain circumstances. To address this issue, several artificial intelligence (AI)‐based methods have been proposed, but they result in complicated and unreliable methodologies. This study introduces the driving training‐based optimization (DTBO) method, which aims to address the partial shading (PS) problem quickly and reliably in maximum power point (MPP) detection for PV systems. DTBO improves tracking speed and reduces fluctuations in the power output during the tracking period. The proposed method is extensively verified using the Typhoon hardware‐in‐the‐loop (HIL) 402 emulator and compared to conventional methods such as particle swarm optimization (PSO), and JAYA, as well as the recently proposed adaptive JAYA (AJAYA) method for MPPT in a PV system under similar conditions. [ABSTRACT FROM AUTHOR]

A switched‐capacitor‐based 13‐level inverter with a lesser number of components is presented in this article. The 13‐level single‐phase AC output voltage is achieved with a voltage gain of 6 by including a single DC source, 11 switches, 4 capacitors, and 3 diodes in the proposed converter. The self‐voltage balancing is achieved for various types of load without the need for complex control schemes and auxiliary circuits. The proposed topology does not require a back‐end H‐bridge to generate negative polarity. This leads to a reduction in voltage stresses across the switches. Thus, total standing voltage (TSV) and the overall cost of the proposed topology are reduced as compared to the state‐of‐the‐art topologies reported in the literature. Furthermore, an Improved Nearest Level Modulation (INLM) scheme is used to improve the power quality of the output voltage. Using the proposed scheme, the Total Harmonic Distortion (THD) of the output voltage is reduced to 5.08%. The power loss analysis for various elements of the proposed converter is also included. A comparison with recent topologies in reference to various performance parameters is carried out. In addition to the simulation study, a laboratory prototype is prepared to validate the efficacy of the proposed converter. [ABSTRACT FROM AUTHOR]

This paper introduces a novel 7‐level active neutral‐point clamped (ANPC) switched capacitor multilevel inverter (SCMLI) with voltage‐boosting capabilities. The proposed converter can produce seven levels and a voltage boosting of 1.5 times with a single dc source. For boosting the voltage, two self‐balanced switched capacitors and two dc link capacitors with active neutral point are used with nine switches. For controlling the output voltage, the level‐shifted modulation technique and modified nearest level control technique is used. The performance of the converter is evaluated with both modulation techniques. The operation of the proposed SCMLI and the design of capacitors for the proposed circuit is discussed in detail. The proposed topology can eliminate the leakage current and has reduced voltage stress across switches which makes it suitable for solar photovoltaic applications. The proposed converter is compared with some other recently introduced converters in terms of voltage gain, the number of components used, and the voltage stress across the switches. For verifying the performance of the proposed circuit, the experimental and simulation results are presented in the paper. The experimental results closely agree with the simulation and theoretical studies. The total harmonic distortion (THD) in the output voltage and efficiency is compared with both modulation techniques. [ABSTRACT FROM AUTHOR]

In recent times, multilevel inverters (MLIs) have become very popular for commercial and industrial applications. Here, an eleven‐level inverter and its power flow control are presented. The presented topology has a lesser component count than other existing topologies, thus reducing the devices and overall cost of the inverter. This inverter comprises six bidirectional switches, two DC sources, one four‐quadrant switch, and two capacitors for the voltage divider circuit. The conduction modes and corresponding switching states of the presented eleven‐level inverter are shown in detail. Further, the apparent power control of the presented inverter under grid‐connected operation is discussed, which provides simultaneous active and reactive power control over the power injected into the grid. Switching and conduction losses are calculated for 3 and 6 kVA grid injected power at 0.8 power factor lagging. The obtained results show that the total harmonic distortion (THD) of the inverter output voltage and grid current is 12.10% and 0.23%, respectively, under 6 kVA power transfer conditions. The real‐time analysis is also carried out for 3 and 6 kVA power transfer conditions for the presented eleven‐level inverter to validate the active and reactive power flow control. [ABSTRACT FROM AUTHOR]

Transmission congestion is one of major drawbacks of deregulated power system. Congestion gradually violates the physical, operational and policy constraints of the present electricity market. Congestion management in huge power system remains a challenging and tough task, which can be achieved by introducing one or more Distributed Energy Resources (DERs) such as Distributed Generation (DG), electric vehicles, modern micro grid, Energy Storage Systems (ESSs) etc. over congested lines. Consequently, this work proposes the hourly congestion management by optimal allocation of DG in '24 hours' time frame. Further, Transmission Congestion Rent is used to determine the optimal and sub optimal locations for DG, whereas Differential Evolution and Particle Swarm Optimization based hybrid optimization technique is exploited to identify optimal DG size. In this work, solar based DG along with battery based ESS is considered to act as Distributed Energy Storage System 'DESS. Subsequently, Interval computation method is introduced in this work to consider the intermittency of solar DG. Battery Energy Storage System 'BESS' is integrated with DGs due to its excess energy storage capability during off‐load period and make it available at peak load conditions, thereby enhancing the overall efficiency of the network. The '24 hours' solar irradiance and temperature data of Delhi, India is taken into account to mathematically model the power generated from Solar DG. The proposed methodology is tested on IEEE 30‐bus system and '24 hours' demand data is generated from the original IEEE load data. From the obtained results, it has been established that the hybrid optimization technique results into a better solution as compared to their individual enforcement in managing available generation resources and congestion problem. [ABSTRACT FROM AUTHOR]

Fault analysis is necessary to design a protection system and circuit breakers for a power system network. The multiphase system is a new technology so very little work is found for the fault analysis of a multiphase system contrary, unlike a three‐phase system. The faults in a seven‐phase system may be either symmetrical or non‐symmetrical. A non‐symmetrical fault requires studying the sequence components of a seven‐phase system using Fortescue transformation. In the paper, non‐symmetrical fault analysis of the seven‐phase system has been analysed. For this, a new definition of sequence components of an unbalanced seven‐phase system has been proposed in this paper. Then the proposed sequence components are applied to different faults studies at the input and output sides of a seven‐phase transformer. Further, the effect of the construction of a seven‐phase transformer, that is, core type and shell type on its output is studied. Moreover, the effect of open‐phase input is analysed using simulation and hardware results. From the analysis, it is found that in certain configurations of a seven‐phase transformer, the seven‐phase output is produced even though open‐phase fault is present at the input while in other configurations, seven‐phase is not produced in the case of open‐phase fault. [ABSTRACT FROM AUTHOR]

ABSTRACT The multiple‐input and multiple‐output (MIMO) DC–DC converters offer various advantages such as improved efficiency and reduced component count. However, the preference of these converters over other types of converters is dependent on the specific application and requirements. Various types of boost‐derived MIMO DC–DC converters are discussed in the literature. However, these converters are either nonisolated or isolated types. In the paper, a MIMO‐based cascaded boost hybrid interlink converter (CBHIC) has been proposed. The proposed converter includes four DC–DC boost converters that are supplied power by two input DC sources. The boosted DC output of these converters can be used independently or in a cascaded manner depending upon the requirement of the load. Further, the cascaded action of these four boost converters leads to the production of two high‐frequency AC outputs. By using bridge rectifiers and high‐frequency transformers, high‐frequency AC voltages are converted into DC. Therefore, two isolated DC output voltages can be achieved using CBHIC. The complementary operation of the cascaded boost converters results in reduction of source current ripples. The design, operating modes, and performance evaluation of the proposed CBHIC have been included in the paper. To validate the efficacy of the proposed CBHIC, a lab prototype of 400 W is prepared. The rms value of high‐frequency AC output voltage at each is isolated port is 141 V. The CBHIC exhibits an efficiency of 94.3 at 400 W. The operation of the converter during voltage control mode is further explored and its dynamic response is studies with the help of experimental results. The obtained simulation and experimental results validate the effectiveness of the proposed converter. [ABSTRACT FROM AUTHOR]