University of Peradeniya

About: University of Peradeniya is a education organization based out in Kandy, Sri Lanka. It is known for research contribution in the topics: Population & Poison control. The organization has 5970 authors who have published 7388 publications receiving 197002 citations.

Co-ordinated voltage control strategy for a doubly-fed induction generator (DFIG)-based wind farm

Abstract: The penetration of wind power into electricity networks is increasing and many large wind farms use doubly-fed induction generator (DFIG) based wind turbines. A voltage control strategy for a DFIG-based wind farm is essential for compliance with some wind farm connection requirements. Such a control strategy may also have commercial benefits. This paper presents a voltage control strategy and illustrates the advantages of this methodology when applied to a DFIG implemented wind farm connected either to a transmission system or embedded within a distribution system. Dynamic linear time invariant models of the DFIG including its associated voltage source convertor and controllers are derived in the synchronous d-q reference frame. In addition, the local on-load tap changer is modelled as a finite state machine and the co-ordinated controllers for both systems are described. Simulation results are presented to illustrate the effectiveness of the controllers within both a transmission system and a distribution system.

An Integrative Study of the Genetic, Social and Environmental Determinants of Chronic Kidney Disease Characterized by Tubulointerstitial Damages in the North Central Region of Sri Lanka

Abstract: OBJECTIVES Previous investigations on chronic kidney disease of unknown etiology characterized by tubulointerstitial damages (CKDu) in the North Central Region (NCR) of Sri Lanka have supported the involvement of social, environmental and genetic factors in its pathogenesis. METHODS We conducted a social-environmental-and-genetic epidemiology study on a male population in NCR to investigate the genetic and environmental contributors. We recruited 311 case-series patients and 504 control candidates. Of the 504 control candidates, 218 (43%) were eliminated because of the presence of hypertension, proteinuria, high HbA1c, high serum creatinine or high alpha-1 microglobulin in urine. RESULTS AND DISCUSSION None of 18 metals measured (μg//) in urine, including Cd, As and Pb, showed significantly higher concentrations in cases compared with controls. As speciation results showed that 75-80% of total urinary As was in the form of arsenobetaine, which is non-toxic to humans. None of the metal concentrations in drinking water samples exceeded guideline values. A genome-wide association study (GWAS) was conducted to determine the genetic contributors. The GWAS yielded a genome-wide significant association with CKDu for a single nucleotide polymorphism (SNP; rs6066043; p=5.23 × 10(-9) in quantitative trait locus analysis; p=3.73 × 10(-9) in dichotomous analysis) in SLC13A3 (sodium-dependent dicarboxylate transporter member 3). The population attributable fraction and odds ratio for this SNP were 50% and 2.13. Genetic susceptibility was identified as the major risk factor for CKDu. However, 43% of the apparently healthy male population suffers from non-communicable diseases, suggesting their possible influence on CKDu progression.