Paper Information

Title: 

V-I CHARACTERISTIC OF SNOW AND ITS ELECTRICAL BEHAVIOR UNDER HIGH ALTERNATING VOLTAGE

Type: PAPER
Author(s): JAVADI HAMID,FARZANEH MASOUD,HEMMATJOU HOSSEIN
 
 
 
Name of Seminar: INTERNATIONAL POWER SYSTEM CONFRENCE
Type of Seminar:  CONFERENCE
Sponsor:  SHERKATE TAVANIR
Date:  2004Volume 19
 
 
Abstract: 

ICE AND SNOW ACCUMULATION ON HIGH VOLTAGE TRANSMISSION LINES MAY CAUSE MECHANICAL DAMAGE TO TOWERS AND CONDUCTORS, AND INCREASE THE CORONA POWER LOSSES OF OVERHEAD LINES. IN ADDITION, DUE TO DAMAGE CAUSED BY GALLOPING OR STEEL JUMP, A NUMBER OF SHORT-CIRCUITS AND OUTAGES OF POWER SYSTEMS, HAVE BEEN REPORTED. ANOTHER MAJOR PROBLEM UNDER THESE CONDITIONS IS INSULATOR FLASHOVER, WHICH HAS BEEN STUDIED TO SOME EXTENT BY RESEARCHERS IN SEVERAL COUNTRIES. A NUMBER OF WORTHWHILE EXPERIMENTAL INVESTIGATIONS HAVE HELPED FURTHER KNOWLEDGE ON THE EFFECTS OF SNOW PARAMETERS ON THE CRITICAL FLASHOVER VOLTAGE OF INSULATORS AND HAVE LED TO THE PROPOSAL OF SEVERAL MITIGATION METHODS. A REVIEW OF MOST OF THE INVESTIGATIONS IN THIS FIELD WAS REPORTED IN RECENT PUBLICATIONS BY IEEE AND CIGRE TASK FORCES. IN SPITE OF A GOOD NUMBER OF VALUABLE INVESTIGATIONS, THESE REVIEWS REVEALED THE NECESSITY OF FURTHER FUNDAMENTAL AND COMPREHENSIVE RESEARCH ON THE PHYSICS OF ARC AND ITS BEHAVIOR ON ICE SURFACES AND INSIDE SNOW. THIS PAPER PRESENTS THE RESULTS OF A LABORATORY STUDY ON THE ELECTRICAL BEHAVIOR OF SNOW-COVERED EQUIPMENT. FROM THE V-I CHARACTERISTICS OF SNOW, AS DETERMINED IN THIS STUDY, IT WAS FOUND THAT THE VOLTAGE ACROSS SNOW AND THE CURRENT THROUGH IT ARE ALMOST IN THE SAME PHASE, WITHIN 2 DEGREES. THIS MEANS THAT AN INSULATOR COVERED WITH SNOW ACTS AS A PURE RESISTANCE. INDEED, THE CAPACITIVE IMPEDANCE OF AN INSULATOR IN PARALLEL WITH SNOW RESISTANCE AT 60 HZ POWER FREQUENCY IS VERY LARGE, AND THEREFORE MAY BE NEGLECTED. THE RESISTANCE OF SNOW IS NOT LINEAR, AS IT DECREASES AS THE VOLTAGE ACROSS IT INCREASES. BASED ON THE RESULTS, A MATHEMATICAL MODEL ALLOWING SIMULATING THE ELECTRICAL BEHAVIOR OF SNOW IS INTRODUCED.

 
Keyword(s): SNOW, V-I CHARACTERISTIC, NON-LINEAR RESISTANCE, FLASHOVER VOLTAGE
 
Yearly Visit 4   pdf-file tarjomyar
 
Latest on Blog
Enter SID Blog