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Input voltage unbalance and sag conditions because of the power system line faults may lead to maloperation of adjustable-speed drive (ASD's). In this paper, the effect of balanced and unbalanced sags on the performance of ASD's has been discussed. The improved performance of ASD's with ultracapacitors is demonstrated using MATLAB simulation.Index Terms--Adjustable-speed drives (ASD's), power quality, ultracapacitors, voltage sag, voltage unbalance.

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Background: Salmonella Typhimurium (S.Typhimurium) adapts to the broad fluctuations of oxygen concentrations encountered in the host. The transition from aerobic to microaerobic/anaerobic condition encountered in the intestine is mainly regulated by fumarate and nitrate reductase (fnr) regulatory gene and aerobic respiratory control A (arcA) gene. Aim is to appraise the role of fnr gene under anaerobic conditions.Methods: In this study, we deleted fnr gene from S.Typhimurium using lambda red-recombinase mediated gene knockout protocol. Further carried out in vitro characterization and analyzed the differential protein expression in wild type (WT) and isogenic Δfnr null mutant (Δfnr) using SDS-PAGE and MALDI-TOF mass spectrometry under anaerobic conditions.Result: In growth competition, WT strain outcompeted the Δfnr and biofilm-forming ability of Δfnr was significantly reduced compared to WT strain. Swimming motility was reduced in Δfnr strain. Besides, differential protein expression revealed the global changes in the expression of many proteins in fnr strain. One differentially expressed protein was identified as TolA, an inner membrane envelope protein. It points out that fnr may regulate the genes responsible for motility and biofilm formation. FNR protein positively regulates TolA, which is important for bacterial virulence, maintenance of membrane integrity, LPS production and replication of bacteria.

Distribution Static Compensator (D-STATCOM) is a custom power device which compensates reactive power and mitigates unbalances caused by various loads in distribution system when it is operated in current control mode. When D-STATCOM is used for load comprehensive compensation, the precision in detecting the compensation current required by the system is very important for compensation effects. There are many detection methods at present. This paper evaluates and analyses three different conventional and extensively used methods of determining the compensating current for a D-STATCOM under abnormal voltage conditions i.e. asymmetric and distorted source voltages and makes comparison of the performance of each one. The algorithms compared are instantaneous reactive power theory (IPRT), synchronous reference frame theory (SRF) and I-cosф algorithm. All three algorithms are simulated under MATLAB environment using Simulink. The theoretical analysis and simulated results illustrate the performance and correctness of these algorithms under asymmetric and distorted source voltages. Finally, the comparison of simulated results has been done to show the accuracy in detecting the harmonics and effectiveness of compensation under abnormal voltage conditions.