T.S. Sidhu

An iterative technique for fast and accurate measurement of power system frequency

This paper describes the design, computational aspects and implementation of an iterative technique for measuring power system frequency. The technique provides accurate estimates to a resolution of 0.01-0.02 Hz for near-nominal, nominal and off-nominal frequencies in about 20 ms. Computation requirements are modest and the technique has been implemented on a modern digital signal processor. The proposed technique was extensively tested using voltage signals obtained from a dynamic frequency source and from a power system. Some test results are presented in the paper.

Accurate measurement of power system frequency using a digital signal processing technique

This paper describes the design, computational aspects, and implementation of a digital signal processing technique for measuring the operating frequency of a power system. The technique provides correct and noise-free estimates for near-nominal, nominal, and off-nominal frequencies in about 25 ms, and it requires modest computations. The proposed technique is implemented using a DSP-based board and has been extensively tested using voltage signals obtained from a dynamic frequency source and from a power system. Some test results are presented in the paper.

A digital technique for stator winding protection of synchronous generators

This paper describes a digital technique for detecting internal faults in stator windings of synchronous generators. The technique uses positive- and negative-sequence models of the synchronous generator, and voltages and currents measured at the generator terminals. It does not need information concerning the machine parameters and is applicable to all types of generators, irrespective of their size. Fault discrimination characteristics and a digital algorithm based on the proposed technique are described. The performance of the proposed technique was evaluated using fault data generated by simulations using an electromagnetic transient program, EMTDC. Fault data were also acquired by subjecting a laboratory generator to internal and external faults. Results of the studies using simulated and experimental data are included in the paper. The results indicate that the proposed technique can detect faults including open circuits and faults that short-circuit windings of one phase.

Modern relays: research and teaching using PCs

It is a general perception that power subjects are concerned with the study of high-voltage, high-current components, such as large machines and high voltage transmission lines. But that is a narrow-minded view. The subject of modern protection, for example, is interdisciplinary by nature. This article describes courses and personal computer (PC) based facilities that are available at the University of Saskatchewan, Canada, with a focus on research and teaching in the area of power system protection. Experience with the use of the laboratory facilities is encouraging and shows enhancements to the quality of teaching and research.

Microprocessor based instrument for detecting and locating electric arcs

A technique that detects the presence of an electric arc is presented in this paper. It is also shown that it is possible to determine its location in a three-dimensional space. The proposed technique can be used to protect power system equipment, such as transformers, inductors, capacitors etc. The technique was implemented and tested in the laboratory. Some test results are also included in the paper.

Arcing fault detection using artificial neural networks

Abstract A technique that detects the presence of arcing faults is presented in this paper. The proposed technique analyzes the radiation produced due to arcing faults. Acoustic, infra-red and radio waves are recorded using appropriate sensors and a DSP-based data acquisition system. The recorded signals are then classified using artificial neural networks. The sensors, data acquisition system and design of the artificial neural networks are described in the paper. The technique was implemented and tested in the laboratory. Some test results are also included in the paper.

A modeling approach for digital protection of synchronous generators

The authors describe the development of an algorithm for detecting internal faults in the windings of synchronous generators. The fault detection algorithm is based on the positive- and negative-sequence models of the synchronous machine. The algorithm uses voltages and currents at the generator terminals to detect the faults. The performance of the proposed algorithm was tested using data recorded from a laboratory generator which was subjected to a variety of internal and external faults. The results indicate that the algorithm effectively detects winding faults.<<ETX>>