Effect of Unaccounted Parameters on Reactive Power Compensation in Indian Electric Traction Line

Abstract

The quest for electrification of railway tracks is very high at developing countries, with a very high ratio of population per kilometre length of railway track. India has electrified almost 50% of its track length and aiming 3000 km track electrification every year. Presently in Indian traction system, all the fault locating methods and power factor correction methods for AC high voltage line are based on the conventional model of railway Overhead Equipment (OHE). The conventional OHE model does not include the effect of self-generated reactive power at the geographically challenged area. This paper explains, how the variations in parasite capacitance of OHE adversely affect the prevailing conventional power factor improving methods; after monitoring the active power, apparent power, leading reactive power injected to improve the power factor of AC high voltage traction system for one calendar year, at two different Traction Sub Stations (TSS). Further simulation of 61 km track with actual mixed geographical terrain to validate the experimental results and to develop a new power factor correction algorithm has been done. The proposed algorithm has been implemented on one TSS of Southern Indian Railways division, and it turns out in reducing penalty around 2.5 million Indian rupees per year, paid by sampling region TSS.

Multi-Objective Real-Time Tuning of SVC Used in Electrified Traction Systems

“…SVC could be considered as the most popular FACTS device with two specific properties: (a) despite all its constructed elements being passive, it can distribute active power between three phases correctly, (b) although SVC is made of the elements with constant impedance, it is able to establish variable impedance in the network [31,32]. Specifically, in the traction system applications, SVC is required in order to fulfill these purposes (a) load current balancing and power factor correction, (b) adjusting the system positive sequence current in an acceptable range, (c) controlling the negative sequence current magnitude in a selectable range [33][34][35].…”