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The increasing proliferation of distributed generators (DGs) demands a robust and comprehensive design of the communication-based adaptive protection scheme, which must be able to not only deal with the known changes in the DGs-distribution system but also handle the unknown changes due to variations in the operating mode, network configuration, and number, type, and size of DGs. On one side, with the increasing installations of DGs, the deployment of the communication system in protection is increasing to monitor the system status and select the relays’ settings accordingly. However, on the other side, if information flow does not happen due to the presence of pre-fault failure of the relay-agents and/or communication links, a protection scheme may fail to provide the suitable protection. This paper proposes a centralized adaptive protection scheme to deal with such failures and varying operating conditions. It provides optimal relays settings for varying operating conditions of the DGs-distribution system with the aim of providing fast, comprehensive, and self-adaptive protection. In order to achieve these objectives, two algorithms have been developed: the first algorithm determines optimal hybrid pick-up settings of the relays, and the second algorithm determines the adaptive hierarchies of the relays. With the inclusion of these two algorithms, the relay coordination problem has been formalized linearly. The performance of the proposed scheme has been tested and validated for various known and unknown events with different types of short circuit faults of different fault impedances on the 37-bus IEEE test distribution system in a MATLAB simulation and coding environment. The results show that the proposed method not only provides the optimal relay's coordination in varying situations but also effectively reduces the protection latency due to pre-fault failures of the relays and communication links, and low level of fault currents. [ABSTRACT FROM AUTHOR]

A wide area measurement system installation cost minimisation and observability maximisation using binary gravitational search algorithm have been reported. Various methods have been employed in the past to determine the optimal locations of devices to retain the observability of the system. However, the costs of communication infrastructure (CI) from phasor data concentrator to phasor measurement units (PMUs) have not been given proper attention. To address this issue, the PMU placement problem has been formulated incorporating the cost of CI also in this study. Contingency cases have also been included to improve the reliability of the system. Besides, the effects of the presence of preinstalled PMUs have been considered. The results obtained for IEEE 14‐bus, 30‐bus and 118‐bus systems have been compared with other methods in the literature. The test results reveal that the proposed methodology produced the PMU locations with higher observability and lesser distance path of establishing communication link compared to an existing method. [ABSTRACT FROM AUTHOR]

Estimation of energy savings in distribution network through smart grid‐enabled conservation of voltage reduction (CVR) approach has been investigated in this study. To achieve higher‐energy savings, CVR operation has been carried out with deeper voltage reduction in association with photovoltaic (PV) system while keeping the node voltages within acceptable limits. The additional reactive power support has been injected by PV inverters. The injected reactive power has been controlled by droop characteristics method. Besides, the moving cloud transient effect has been incorporated in PV power output. To evaluate the energy savings, the volt‐VAR control operation has been carried out in three different modes such as without CVR, only CVR, and CVR with PV system on the modified unbalanced IEEE 123 node test system. The test system and control algorithms have been developed and simulated in open distribution system simulator interfaced with MATLAB. From simulation results, it has been demonstrated that higher‐energy savings and peak load demand reduction can be achieved through smart grid‐enabled CVR and PV system in comparison with the only CVR with proper voltage regulation. [ABSTRACT FROM AUTHOR]

Knowledge of both voltage and current data is conventionally entailed for locating fault on transmission network. However, owing to the non-linearity of the system, the process becomes iterative and cumbersome. In order to address this issue, a new technique for fault location on transmission lines using only voltage measurements obtained from Wide Area Measurement Systems (WAMS) and the network bus admittance matrix has been reported in this paper. It is based on the fundamental law of electrical networks. It delineates a single step method to find out the faulted line and the exact location of fault. The decision is based on change in injected current at various buses following the line fault. The method has been tested on IEEE 14 bus and New England 39 bus system. Applicability of the proposed algorithm is independent of fault type, location of fault and fault resistance. This method not only proves to be accurate but also furnishes quick results with reduced computational burden. Besides, the faulted phase as well as fault type detection has been suggested in this paper using same measurements. [ABSTRACT FROM AUTHOR]

A wide area measurement system installation cost minimisation and observability maximisation using binary gravitational search algorithm have been reported. Various methods have been employed in the past to determine the optimal locations of devices to retain the observability of the system. However, the costs of communication infrastructure (CI) from phasor data concentrator to phasor measurement units (PMUs) have not been given proper attention. To address this issue, the PMU placement problem has been formulated incorporating the cost of CI also in this study. Contingency cases have also been included to improve the reliability of the system. Besides, the effects of the presence of preinstalled PMUs have been considered. The results obtained for IEEE 14-bus, 30-bus and 118-bus systems have been compared with other methods in the literature. The test results reveal that the proposed methodology produced the PMU locations with higher observability and lesser distance path of establishing communication link compared to an existing method. [ABSTRACT FROM AUTHOR]

Transmission congestion is one of the most challenging issues in operation of deregulated electricity markets of today. This study investigates into benefit of unified power flow controller (UPFC) as a viable solution to the problem of congestion management. A comprehensive load flow model for the UPFC is presented which has the capability to control active and reactive powers and voltage magnitude simultaneously. This study discusses about two different approaches for determination of suitable location of UPFC. One of them is sensitivity‐based approach and the other is pricing‐based method. Reduction in total system losses has been taken as objective in sensitivity‐based approach. Furthermore, sensitivity of total system losses with respect to control parameters of UPFC have been evaluated using two different methods. A pricing‐based approach which makes use of locational marginal price difference and congestion rent for determination of suitable location of UPFC. Minimisation of cost of rescheduling subjected to system operating constraints is the objective to be met for congestion management. Interior point method, a mathematical tool for non‐linear optimisation, is used to obtain the solution of above‐mentioned problem. [ABSTRACT FROM AUTHOR]

This study proposes a solution to the optimal power flow (OPF) in power systems incorporating wind power. The wind generated electricity's cost modelling is presented which owes to the stochastic nature of wind speed based on the Weibull probability density function. The wind associated costs comprise of (i) reserve cost arising out of overestimation of wind farm output and (ii) penalty cost for not using total available wind power which are included in the conventional OPF. Furthermore, the Q‐V formulation of induction generator is deduced which is incorporated through a modification in the conventional load flow solution. A modified cuckoo search optimisation technique is employed and compared with modified particle swarm optimisation for solving OPF with wind power involved. A modified IEEE 30‐bus and IEEE 57‐bus systems are used as test systems and it is observed that the cuckoo search performs better than particle swarm optimisation. [ABSTRACT FROM AUTHOR]

Abstract: A method based on radial basis function neural network (RBFNN) architecture is proposed for fast and accurate post-contingent information evaluation, contingency screening and ranking. Estimation of bus voltage magnitude is desired for voltage based contingency analysis whereas estimation of MW, MVA and Mvar line flows are required for power flow based contingency analysis. However, knowledge of voltage magnitudes and angles of all system buses are sufficient to determine the above quantities. Therefore, two neural networks; one for voltage magnitude and other for voltage angle estimation corresponding to normal as well as each contingent condition are proposed in this paper. These estimates are further used to compute two types of performance indices (PIs) for contingency screening and ranking. These PIs are comparable with those obtained by power flow analysis. The effectiveness of proposed method is demonstrated on two IEEE test power systems. Since accurate bus voltage magnitude and angle predictions are achieved quickly by the proposed method, the developed neural networks provide valuable information to operators in real-time operation. [Copyright &y& Elsevier]

• Optimal EV/ESS scheduling to minimize the operational cost. • An uncertainty model to predict EV availability at charging station is proposed. • Schedule optimization is modelled as a mixed integer problem. • The proposed technique is compared with four well known meta-heuristic techniques. • Incentive based pricing is proposed to increase the EV participation. The paper emphasises on optimal operation of community based microgrid with Photovoltaic (PV), Energy storage system (ESS) and Electric vehicle (EV) as an alternate source of power. The energy stored in EVs is utilized as a source of power for home and grid by proposing bidirectional power flow strategies. Bidirectional power flow from EV/ESS is regulated by controlling the charge/discharge rate. This control strategy is based on the EV availability, loading on transformer and the day ahead prices. A technique is introduced based on markov model using factual hourly data of vehicle usage to predict the EV availability. The primary aim of this paper is to maximize economic benefit for the prosumers with minimal battery degradation. The Charge/Discharge regulation and battery degradation of EV/ESS is modelled as mixed integer problem and optimal solution is determined by Mixed integer linear programming (MILP) using IBM CPLEX optimizer to achieve maximum economic benefit. A comparative analysis to demonstrate the efficacy of the proposed technique with four well known meta-heuristic techniques has been discussed. Impact of vehicle availability at charging station on total operational cost is assessed to study the grid dependency. The paper also proposes an incentive based pricing strategy to increase the EV participation in energy transaction by reducing the grid dependency. [ABSTRACT FROM AUTHOR]

The focus of this paper is on analyzing the impact of conservation voltage reduction in the presence of active devices such as solar photovoltaic (PV) and developing controls that leverage these distributed energy resources. An event-driven predictive approach for real-time volt/volt-ampere reactive (VAR) optimization, along with a local two-level adaptive volt/VAR droop-based control algorithm for advanced distribution management systems, is introduced. The methodology covers aggregated and autonomous controls under different timescale operations, including the impact and effect of unpredicted events such as cloud transients on PV power production. Besides, the control schemes include the uncertainties in PV power generation and load power demand. The proposed methodology is validated in a real-time framework using the real-time digital simulator platform through co-simulation with models based on Python and OpenDSS (Open Distribution System Simulator). The developed methodology is tested on the modified IEEE 123-feeder test system. The results reveal that the proposed methodology works well in the presence of high penetrations of PV power, produces significant energy savings, and mitigates over-/undervoltage problems. [ABSTRACT FROM AUTHOR]

Summary: The objective of the present work is to investigate a decentralized optimal power flow decision‐based congestion‐free operational strategy in multiutility power markets that maximizes the social welfare. The effects of network losses incurred by various utilities on social welfare of the market have also been investigated. As a result, it can resolve the market disputes due to the problem of congestion and allocation of the additional cost of generation caused by transmission losses. The centralized optimal power flow decision‐based strategy has also been adopted to address the problem. In this work, a new optimization method, interior point–initialized particle swarm optimization (IP‐PSO) method, has been introduced to solve the mentioned problem. The method harnesses the benefits of both interior point method (IPM) and particle swarm optimization (PSO) method. To facilitate the faster optimal solution, results obtained using IPM has been used to initialize PSO solution. The proposed study has been performed on the modified IEEE‐30 bus and modified IEEE‐118 bus systems. The results show the effectiveness of decentralized optimal power flow decision‐based strategy over centralized optimal power flow decision‐based strategy using IPM, sequential quadratic programming, PSO, IP‐initialized sequential quadratic programming, and IP‐PSO methods. [ABSTRACT FROM AUTHOR]

• A fast and non spurious IDT using a modal voltage signal has been presented. The islanding/non-islanding condition has been detected without directly impacting the system operation. • The proposed method is well competent in ascertaining the islanding below 2 s in the case of a zero power deficit. • The analysis of NDZ of the proposed VMD based IDT is also carried out using anti-islanding requirements specified by UL 1741 Std. • The proposed IDT is applicable for all types of DG. • A real-time simulation and validation of the proposed method has been carried out on the RTDS/RSCAD and dSPACE platform to reaffirm its efficacy and feasibility on real world problems. Ascertaining unintentional islanding conditions is a challenging task for power utility operators due to the pervasive penetration of Distributed Energy Resources (DER). The presence of DER has a significant adverse impact on islanding detection schemes for various types of Distributed Generators (DG) and inverters. This paper addresses the passive islanding detection mechanism based on the mode energy index using Variational Mode Decomposition (VMD) in an Active Distribution Network (ADN). The prime attributes of VMD are noise immunity, robustness, and non-recursive signal processing, making it more promising and competent for signal decomposition than other extant signal processing methods. In this paper, three-phase instantaneous voltages at the target DG end have been acquired to compute modal voltage signals, and VMD has been utilized to decompose the obtained signals into four modes. Thereupon, the energy was calculated for the selected mode. In the context of threshold selection, a series of simulation is carried out for various islanding and non-islanding events. The energy threshold is then selected by implementing "Otsu thresholding method". The estimated energy index has ultimately been utilized as an islanding detection indicator. In this work, two different test systems have been modelled and simulated using EMTDC/PSCAD. The simulation result outcomes asserted that the developed approach effectively ascertains the islanding and non-islanding events. Furthermore, the proposed islanding detection technique has been validated using the Real-Time Digital Simulator (RTDS) and dSPACE MicroLabBox based co-simulation platform. [ABSTRACT FROM AUTHOR]

Abstract: The reaction of 2-hydrazino-3-methylquinoxaline 1 with trifluoromethyl-β-diketones 2 not only yields the expected 5-trifluoromethyl-5-hydroxy-Δ2-pyrazolines 3a–3f and/or 3-trifluoromethylpyrazoles 4c–4f but also the unexpected products 1,2,4-triazolo[4,3-a]quinoxalines 5a–5f and/or 3(5)-trifluoromethyl-1H-pyrazoles 6c–6f. Furthermore, the acid-catalyzed dehydration of 5-hydroxypyrazolines 3a–3b resulted in the formation of unexpected 5a–5b along with the expected corresponding pyrazoles 7a–7b. These unprecedented observations provide evidence for the existence of equilibrium between the hydroxypyrazoline 3 and its open chain tautomer, ketoimine 9 in the mechanistic path leading to the formation of pyrazoles 7 and triazoles 5. [Copyright &y& Elsevier]

Abstract: Reaction of hydroxylamine hydrochloride with aryl trifluoromethyl-β-diketones affords 5-hydroxy-5-trifluoromethyl-Δ2-isoxazolines rather than the reported 3-trifluoromethylisoxazoles. The structural assignment is based on the analysis of their NMR (1H, 13C and 19F) spectral data and of their dehydration products, 5-trifluoromethylisoxazoles. [Copyright &y& Elsevier]

Abstract: The regioselective synthesis of 1-heteroaryl-5-amino-4-phenylpyrazoles 3a–g and 1-heteroaryl-5-amino-3-methyl-4-phenylpyrazoles 3h–n was achieved by the treatment of heteroarylhydrazines 1a–g with α-phenylformylacetonitrile 2a and α-phenylacetylacetonitrile 2b, respectively. The structures of the compounds 3 were established by the combined use of 1H and 13C NMR spectroscopy. All the fourteen compounds were tested for their in vitro antibacterial activity against three Gram-positive and two Gram-negative bacteria. Six compounds 3a, 3d, 3e, 3g, 3l, and 3n from this series were found to be equipotent or more potent than the commercial antibiotics (Linezolid and Cefroxime axetil). [Copyright &y& Elsevier]

Arylhydrazones of dehydroacetic acid (DHA) underwent Vilsmeier–Haack reaction to generate the corresponding 1-aryl-4-formyl-3-(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)pyrazoles (1) with the pyrone moiety of the DHA remaining intact. However, when the reaction was performed using 1 equiv. of the reagent, compounds of 1-aryl-3-(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)pyrazoles (2a–2f) were obtained, which underwent smooth conversion to 1-aryl-4-formyl-3-(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)pyrazoles (1) on further treatment with another equivalent of the Vilsmeier–Haack reagent. This unreported observation suggests the intermediacy of 1-aryl-3-(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)pyrazoles (2) in Vilsmeier–Haack reactions of hydrazones with a pyrone moiety. Several analogous compounds were also prepared using arylhydrazones of DHA. [ABSTRACT FROM AUTHOR]

Abstract: Treatment of 1,1,1-trifluoromethyl-3-cyano-3-phenylpropanone (1) with several heteroarylhydrazines (2a–e) in refluxing ethanol affords 1-heteroaryl-5-amino-4-phenyl-3-trifluoromethylpyrazoles (4) in a regioselective manner. The location of trifluoromethyl group at position-3 was established by a combined use of 13C and 19F NMR spectroscopy. The reaction proceeds through the intermediacy of the hydrazone which was isolated and characterized in one case (3e) by performing the reaction at room temperature. The compounds 3e and 4 were tested for their antibacterial property against six Gram-positive and three Gram-negative bacteria. Two compounds, namely 1-(benzothiazol-2′-yl)-5-amino-4-phenyl-3-trifluoromethylpyrazole (4a) and 1-(6′-methylbenzothiazol-2′-yl)-5-amino-4-phenyl-3-trifluoromethylpyrazole (4b) have displayed antibacterial activity comparable to the commercial antibiotics. [Copyright &y& Elsevier]

Abstract: Treatment of α,β-unsaturated carbonyl compounds, obtained by the reaction of DHA and aromatic (or heteroaromatic) aldehydes, with o-aminothiophenol results in the formation of 1,5-benzothiazepines and/or 1,4-benzothiazines depending upon the reaction conditions and structure of the aldehydes. The products were characterized by the combined use of multinuclear 1D and 2D NMR and GIAO/DFT calculations of 1H, 13C and 15N chemical shifts. The tautomerism of these compounds in solution was determined, they have an exocyclic CC double bond. [Copyright &y& Elsevier]

An improved method for thiocyanation of 2-arylindan-1,3-diones, phenols, and anilines using a reagent combination of (dichloroiodo)benzene and potassium thiocyanate in dry dichloromethane is described. [ABSTRACT FROM AUTHOR]

Lithium is frequently used as an effective drug for the treatment of several psychiatric disorders in human. This alkali element and its salt, at its higher doses, may lead to various side effects or has several toxic effects after prolonged therapeutic use. To test this hypothesis, the present study was designed to investigate the adverse effect of subchronic exposure of lithium carbonate on reproductive organs of male rat. Rats were exposed to lithium carbonate at doses of 500, 800, 1100 mg/kg of diet for 90 days. The weight of reproductive organs, histology of testis, epididymis, seminal vesicle, prostate, testicular interstitial fluid volume (IFV), testosterone level, sperm morphology and fertility index were analyzed. Treatment with higher doses of lithium carbonate (i.e. 800, 1100 mg/kg diet) significantly reduced testes, epididymis and accessory sex organs weights, whereas, lower dose (500 mg/kg diet) did not show any untoward effect. Similarly, the sperm number from cauda epididymis and daily sperm production was significantly decreased with higher doses of lithium carbonate. The serum testosterone levels and IFVs were also reduced significantly. Seminal vesicle and prostate secretions were completely blocked and spermatozoa were not seen in the lumen of epididymis and vas deference. Histological studies have revealed that lithium carbonate (1100 mg/kg) caused degeneration of spermatogenic cells and vacuolization of sertoli cells cytoplasm in the testis. The sperm transit rate and production of abnormal spermatozoa were significantly (P<0.01) increased. When the lithium carbonate-treated males were mated with normal cyclic females, the fertility index declined to 50% even after 30 days of withdrawal of lithium carbonate treatment. These results clearly suggest that subchronic exposure of lithium carbonate promote reproductive system toxicity and reduces fertility of male rats. [Copyright &y& Elsevier]

The reaction of o-phenylenediamine with 3-cinnamoyl-4-hydroxy-6-methyl-2-pyrones (3a–i, chalcone analogs of dehydroactic acid) in ethanol-acetic acid provides a facile method for the synthesis of 3,4-dihydro-2-pyronyl-1,5-benzodiazepine derivatives (2a–i). [ABSTRACT FROM AUTHOR]

Examines the role of (dichloroiodo)benzene and lead(II) thiocyanate in dichloromethane. Oxidation of enol silyl ethers, ketene silyl acetals and beta-dicarbonyl compounds; Use of thiocyanates in organosulfur chemistry; Method of preparing alpha-thiocyanato carbonyl compounds.

Abstract: A mild and efficient synthetic protocol for the oxidation of benzil-α-arylimino oximes 3 utilizing iodobenzene diacetate (IBD) as an oxidizing agent has been developed. Oximes 3, obtained by the condensation of (E)-benzil monoxime 2 with various appropriately substituted anilines 1, on treatment with iodobenzene diacetate in dichloromethane at room temperature underwent oxidative cyclization to afford 2,3-diphenylquinoxaline-1-oxide 4 in excellent yields. [Copyright &y& Elsevier]

Spot blotch (SB) in barley is caused by the fungal pathogen Cochliobolus sativus and considered one of the major constraints to successful barley production. Resistance to C. sativus was evaluated, using a barley collection of 336 genotypes (AM-2014), at the seedling and adult stages. Seedling resistance was evaluated by using a mixture of 19 virulent isolates in Morocco. Virulent isolates prevalent in Uttar Pradesh were used for phenotyping resistance at the adult stage in India. The AM-2014 panel was genotyped with 9-K single-nucleotide polymorphism (SNP) markers using iSelect Illumina Infinium. Genome wide association studies (GWAS) were carried out using SNP markers, infection responses, disease severity, and area under the disease progress curve (AUDPC). The mixed linear model was employed in TASSEL using principal component analysis (PCA) and Kinship matrix (K) as covariates. Higher SB severity, 82.3 ± 13.5 (mean ± SD), was recorded at the Banaras Hindu University (BHU) compared to 47.6 ± 15.0 at the Narendra Dev University of Agriculture and Technology (NDUAT). Nine QTL, Rcs-qtl-1H-126.9, Rcs-qtl-2H-148.16, Rcs-qtl-3H-25.27, Rcs-qtl-5H-80.35, Rcs-qtl-6H-58.24, Rcs-qtl-7H-29.62, Rcs-qtl-7H-29.72, Rcs-qtl-7H-32.81, and Rcs-qtl-7H-34.74, were detected for SB resistance at the seedling stage. For SB severity at the adult stage, a QTL, Rcs-qtl-7H-32.81, was detected at BHU while seven QTL, Rcs-qtl-2H-91.09, Rcs-qtl-3H-145.64, Rcs-qtl-4H-14.43, Rcs-qtl-6H-6.49, Rcs-qtl-7H-114.43, Rcs-qtl-7H-151.66, and Rcs-qtl-7H-150.36, were found for SB severity at NDUAT. Three QTL, Rcs-qtl-4H-18.61, Rcs-qtl-4H-67.91, and Rcs-qtl-5H-110.25, were significant for AUDPC of SB at BHU. The QTLs reported in this study are important to advance marker-assisted selection and gene pyramiding of SB resistance in South Asia and North Africa in future. [ABSTRACT FROM AUTHOR]