Fast Fourier Transform

Harmonics estimation in emerging power system: Key issues and challenges

Power quality problems are manifested in voltage, current or frequency deviations causing malfunction of sensitive equipment. Integration of inverter connected PV and wind power plants, and rampant rise in nonlinear loads have led to harmonic problem in power system. Nonlinear loads and switched devices energized by sinusoidal sources or linear loads and switched devices with non-sinusoidal sources, produce harmonics in distribution system. Academic harmonic analysis study consists of modeling nonlinear loads to develop Norton and Thevenin equivalent circuits of devices for integration into harmonic analysis software. Experimental researchers often use harmonic analyzers to measure the harmonics in real systems to evaluate suitable mitigation alternatives. The distortive power losses force utilities to increase apparent power to maintain reliable and uniform power supply. Harmonic analyzers use data acquisition hardware and inbuilt software algorithms to perform onsite measurements. Harmonic analyzers help find true power factor, total harmonic distortions, reactive and distortive power losses. Use of shunt capacitance at unity power factor worsens the situation instead of supplying distortive power compensation. Active power factor correction techniques, using smart algorithm to cancel the distortive power, have been reviewed for further research. Nonlinear physics of harmonic phenomenon is described to explore its applications. Harmonic mitigation technologies have been compared, current state of the art technology reviewed and demonstrated by designing a harmonic filter. Measurement of harmonics, waveform distortions, and true power factor (TPF) of single and three phase electronic loads is carried out to test their compliance to harmonic standard limits. Energy conservation concept requires reduction of harmonics in distribution networks. This study found 60±10% reduction in power factor and more than 2% increase in line losses due to widespread use of nonlinear loads. Utility apparent power demand increases due to consumers’ inadvertent violation of IEC Standard 61000-3-2 and IEEE Standard 519–1992.

Review of harmonic analysis, modeling and mitigation techniques

In this paper, different Distribution Static Compensators (DSTATCOMs) topologies, state of the art, their performance, design considerations, future developments, and potential applications are investigated for power quality improvement. These DSTATCOMs for three-phase three-wire systems and three-phase four-wire systems are developed and installed in the distribution system for many functions, such as reactive power compensation, harmonics elimination, load balancing, and neutral current compensation. This paper is aimed to explore a broad perspective on DSTATCOMs to researchers, engineers, and the community dealing with the power quality improvement. A classified list of some latest research publications is also provided for quick reference.

Comprehensive Study of DSTATCOM Configurations

Introduction to Variance Estimation (2nd ed.)

The chapter starts with an introduction of power quality. Different aspects are then discussed to define electric power quality. Different sub-branches in power quality study are discussed. After this, disturbances normally occurred in power system are discussed. Short definitions of these power system disturbances are presented. Power quality related problems are summarized. Different guidelines given by IEC, IEEE, etc. are presented in tabular form.

Electric Power Quality

Induction Motor Fault Diagnosis

A self-synchronized ADALINE network for on-line tracking of power system harmonics

This paper develops a model for shipping of container vessels to fulfill the demand and supply in various ports in a fixed time frame with dynamic demand and supply of each port under fuzzy environment. The time frame is divided into sub-frames which are operation time and travelling time. Speed optimization, simultaneous loading, unloading operation, and load factor are introduced to reduce fuel consumption and carbon emission. The risk factor is introduced to make the problem more realistic. In the real ship routing scenarios, different cost parameters are not always deterministic, and fluctuate imprecisely. The imprecise cost parameters are considered as Triangular Fuzzy Number (TFN). A modified genetic algorithm is used to solve the proposed model, and numerical examples are given to illustrate the efficiency of the proposed algorithm. 

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Samarjit Sengupta

Papers

Electric Power Quality

Induction Motor Fault Diagnosis

A self-synchronized ADALINE network for on-line tracking of power system harmonics

Solving fuzzy dynamic ship routing and scheduling problem through new genetic algorithm

Detection of Induction Motor Broken Bar Fault Through Envelope Analysis Using Start-Up Current