Product - Power Quality Analysis And Harmonic Mitigation Solution
Purpose of the Analysis:
It is to foresee or predict the quality of power that is being maintained at customer site and the Harmonics level managed. It is strange to note that we are really neither aware that we should have Quality Power nor much care to utilize it healthily. This study emphasize as many of the dangers and problems that would arise due to poor quality & Harmonics.
TNEB has mandated to limit harmonic distortion starting from the year 2012, which in turn is based on CEA-2007 regulation, devised to improve quality of power supply as well as to stabilize & prevent it from a sudden collapse by re- living it together with connected generating stations from the cascading effects of a possible built up of a stressful power system conditions. It is difficult to deconstruct the root cause of a grid collapse. And even after a decade no convincing reason has emerged from the American grid collapse. It is however certain that grid collapse when multiple reasons swell up cascading one after another and reach the threshold trigger point. Power quality harmonic is one of the major constituents that define a stable grid. Power surge viz. voltage sag, which is also a consequence of power quality harmonic; is the single major cause that inflicts billions of dollars damages in terms of industrial equipment failures and productivity losses every year worldwide. Further electrical harmonics are unpredictable and under favorable power systems impedance, trigger harmonic resonance that magnifies harmonics as well as power fluctuations in the grid supply.
HARMONIC LIMITS IN ELECTRIC POWER SYSTEMS (IEEE 519 1992)
The harmonic voltage limitations set forth by IEEE 519 1992 are:
1) Maximum Individual Frequency Voltage Harmonic: 3%
2) Total Harmonic Distortion of the Voltage: 5%
Harmonic limitations have been established by IEEE 519 1992 for the following reasons:
o To limit the damage to power factor correction capacitors and harmonic filter systems caused by excessive har- monics
o To prevent series or parallel resonance in the electrical system
o To keep the level of harmonics at the PCC (Point of Common Coupling) from being excessive and distorting the system voltage and damaging other equipment on the system
o The PCC is defined as the electrical connecting point or interface between the utility distribution system and the customers electrical distribution system.
Power quality can be defined as the comparison of voltage and current wave forms to their fundamental clean sinusoidal wave forms. Pure sine waves that are free from distortion are sometimes referred as Clean Power Harmonic distortion is one of the main causes of the power quality problems. Many papers have been written on this subject & now we present a brief review of the subject is presented here. Quality of power and Service reliability have become growing concerns for many facility owners and managers, especially with the increasing sensitivity of electronic equipment and automated controls. There are several types of volt- age fluctuations that can cause problems, including surges and spikes, sags, harmonic distortion and momentary disruptions.
Harmonics can cause sensitive equipment to malfunction and other problems, including overheating of transformers and wiring, nuisance breaker trips and reduced power factor. It is the main intent of this analysis to discuss the Harmonic distortion in the Electrical System and to present some design ideas and solution that should be considered when trying to decide whether harmonic mitigation is necessary, and if so, what should be implemented.
BASIC UNDERSTANDING OF HARMONICS IN ELECTRICAL SYSTEMS:
By simple definition Harmonics are any "Non-Linear" Current or Voltage in an electrical distribution system. An Electrical Harmonic shouldnt be thought of as an acoustic or vibration harmonic, but simply any electrical device that draws current un-proportionally to voltage. To be more precise, A Harmonic is a Wave whose frequency is an integer multiple of the fundamental frequency [50 Hz] The French Mathematician Joseph Fourier coined the term Harmonics out of studies in relation to sound in the early 1800s From these studies, he developed methods to describe sets of complex repeating wave forms as sums of simple sinusoidal wave forms. When the higher frequencies are added to fundamental, it will result in a Distortion of the fundamental frequency- 50 H z.
STUDY AND SOLUTIONS:
We give suggestions and remedial measures to Plan, Organize and Control activities to arrest the Harmonic issues and maintain the quality of power, so that projects are carried on as successfully as possible inspite of all the related risks. We provide solutions for such issues through installing Harmonic filter panels equipped with capacitor banks.