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This paper proposes a novel wavelet-transform-based directional algorithm for busbar protection. The algorithm decomposes the current and voltage signals into their first-level details, which consist of frequencies in 500- to 1000-Hz bandwidth, for generating directional signals. A high level of computational efficiency is achieved compared to the other wavelet-transform-based algorithms proposed, since only the high-frequency details at the first level are employed in this algorithm. The validity of this method was exhaustively tested by simulating various types of faults on a substation modeled in the Alternative Transients Program/Electromagnetic Transients Program. The algorithm correctly discriminated between bus faults, various types of external faults, and transformer energization even in the presence of current-transformer saturation. This paper also provides the design details of the algorithm using field-programmable gate array technology. Index Terms--Busbar protection, detail coefficients, digital directional relay, field-programmable gate array (FPGA) implementation, wavelet transforms.

Application of object-oriented design patterns for the development of power system computation software is presented. Important patterns such as 'Iterator,' 'Decorator,' and 'Template Method' are utilized to develop a comprehensive power flow (load flow) analysis program, including FACTS devices such as SVC, TCSC, STATCOM, and UPFC. Analysis-independent object models of power system components are obtained by untying the attributes required for computation from the attributes representing the physical characteristics of an object. The proposed object-oriented design of power flow computation has been implemented in C++ on windows environment. The performance of the developed program has been tested with IEEE benchmark systems. Index Terms--Design patterns, FACTS devices, object-oriented development, power flow analysis, power system computation.

Solution methodology of unit commitment (UC) using genetic algorithms (GA) is presented. Problem formulation of the unit commitment takes into consideration the minimum up and down time constraints, start up cost and spinning reserve, which is defined as minimization of the total objective function while satisfying the associated constraints. Problem specific operators are proposed for the satisfaction of time dependent constraints. Problem formulation, representation and the simulation results for a 10 generator-scheduling problem are presented. Index Terms--Optimization, genetic algorithms (GA), unit commitment (UC), economic dispatch (EC).

Power restoration schemes incorporated into Distribution Automation (DA) system helps in quickly restoring the power during emergency situations like faults. Due to the numerous advancements made in the distribution system operation in recent times, power restoration analysis needs to be done in a look‐ahead manner based on system wide operational & monitored data apart from just fault data processing during the outages. With the evolution of Advanced Metering Infrastructure (AMI) during recent times, it is now possible to design the look‐ahead restoration schemes by integrating the operation of DA with AMI system using internet protocol based communications, preferably. In this paper, we propose a novel method for power restoration analysis which execute all pre‐defined restoration schemes in a look‐ahead manner by representing distribution system as a weighted graph and computing graph weights based on representation of DA & AMI system's current operational/measured/constraint data from each distribution load segment. Computed graph weights are converted to restoration indices with associated ranking based mechanism to indicate criticality & considerations for each power restoration scheme in case of fault occurrence in real‐time. A case study on the standard RBTS test system has been demonstrated for the proposed method. [ABSTRACT FROM AUTHOR]

Magnetic Bearing, especially Active Magnetic Bearing (AMB) is arguably most preferred bearing for the process dealing with highly reactive environment, high speed operation and where the process required least contamination. They are also being tried for Fly wheels and Wind generators. They continue to be evolved since last several decades. Quite a few processes like application of AMB in high temperature Liquid Sodium high temperature applications call for development of large-working-gap active magnetic bearings (AMB). Smooth operation of AMB depends on hypersensitive position stiffness and Current stiffness, which fluctuates due to differential-thermal-expansion induced air gap variation. So, large gap, necessitates flatter open loop position stiffness than that of contemporary magnetic actuators. In this work, a goal seeking optimization methodology is employed for double acting AMB system where a combination of higher (CRGO electrical steel) and lower saturating magnetic material (Mu metal) is used. A less variant position stiffness across the air gap was arrived at after getting optimized design variables constituting geometry and excitation current parameters. This investigation opens up a new way to attain position stiffness in AMB system which is less sensitive to positional variation of rotor in air gap. This paper proposes an innovative and first-of-its-kind bi-material core material with goal driven optimized magnetic actuator design which can afford to have air gap variation during operation. [ABSTRACT FROM AUTHOR]