AN EXAMPLE OF APPLYING ALGORITHM TO CREATE THE ACTUAL PQ DIAGRAM OF A HYDROGENERATOR

U radu je prikazana provedba metodologije određivanja korisničke pogonske karte na primjeru hidroagregata br. 3 u HE Vinodol. Kao predložak u pripremi podloga i sustavnom određivanju granica dopuštenog rada agregata poslužio je blok dijagram sa slike 15 u [1], koji na pregledan način ocrtava tijek provedbe pojedinih radnji potrebnih za tvorbu korisničke pogonske karte. Svi međukoraci su dokumentirani, a dobiveni rezultati prikazani tablično i grafički. Svaka od konačno određenih granica je ucrtana u korisničku pogonsku kartu promatranog agregata. S obzirom na složenost provedbe proračuna graničnih uvjeta koje nameću elektromagnetska i toplinska zbivanja u čeonom prostoru, u radu je na konkretnom primjeru iz prakse prikazana potpuno nova metodologija utvrđivanja graničnih vrijednosti uzdužne komponente magnetske indukcije, temeljeno na rezultatima mjerenja indukcije i pripadne nadtemperature u trajnom kapacitivnom radu generatora. Predložena metoda je primjenjiva za bilo koji sinkroni generator.The work describes the application of the methodology of defining the actual PQ diagram on the example of Hydrogenerator-turbine unit No. 3 at Vinodol Hydroelectric Power Plant. Used as a basis for preparing documents and determining the unit’s operating tolerances was a block diagram in Figure 15, contained in [1], which provides a clear survey of the sequence of steps required to create an actual PQ diagram. All intermediate steps are documented and the obtained results are shown in tables and graphics. Each of finally defined limits is imported into the actual PQ diagram of the observed unit. Considering the complexity of calculating the limit conditions imposed by electromagnetic and thermal occurrences in the end region, in a concrete example from practice the present work describes an entirely new methodology of determining the limit values of the longitudinal magnetic induction component, based on the results of measuring induction and pertaining over-temperature in the generator’s permanent capacitive operation. The proposed method is applicable to any synchronous generator

METHODOLOGY FOR DETERMINING THE ACTUAL PQ DIAGRAM OF A HYDROGWENERATORS

U radu je predočena metodologija određivanja pogonske karte kao ključnog dokumenta svake proizvodne jedinice električne energije. Opisane su sve granice od kojih se sastoji pogonska karta hidrogeneratora. Detaljno su izložene teorijske podloge na kojima leže postupci za njihovo određivanje. Poseban osvrt je dan manj eistraženom problemu zagrijavanja čeonog prostora hidrogeneratora. Pregledno je prikazan i obrazložen slijed postupaka koji sačinjavaju metodologiju. Detaljne analize i proračuni, posebno korištenjem suvremenih numeričkih programskih alata, daju dobar uvid u mogućnost rada generatora i mogu poslužiti kao priprema za ispitivanja i mjerenja. Rezultati dobiveni mjerenjima i ispitivanjima obrađuju se i tumače, te se tek na osnovu tako dobivenih rezulatata sa sigurnošću određuju granice dozvoljenog rada generatora. Konačan rezulatat provođenja ispitivanja prema predloženoj metodologiji je korisnička pogonska karta: stvarna, mjerenjem potvrđena pogonska karta hidrogeneratora.This paper presents the methodology for determining the actual PQ diagram as a key document for any power generation unit. It describes all the limits of which a hydogenerator PQ diagram consists. There is detailed explanation of the theoretical basis of the procedures for their determination. It also contains a reference to the less researched problem of heating in the hydogenerator end region. The paper clearly shows and explains the sequence of the procedures which make up the methodology. Deatiled analysis and calculations, particularly using modern numerical programming tools, provide a good insight in generator performance and may serve as a preparation for testing and measuring. The measurement and testing data is processed and interpreted, and it is only on the basis of the result thus established that the limits for the permitted operation of the generator are positively determined. The final result of the testing conducted in accordance with the methodology proposed is actual PQ diagram: the real PQ diagram of the hydrogenerator, confirmed by the maesurement

New method of Scoliosis Deformity Assessment: ISIS2 System.

Scoliosis deformity has been assessed using radiographic angle measurements. Surface topography systems are an alternative and complementary methodology. Working systems include the original ISIS1 system, Quantec and COMOT techniques. Over the last five years the new ISIS2 (Integrated Shape Imaging System) has been developed from basic principles to improve the speed, accuracy, reliability and ease of use of ISIS1. The aim of this study was to confirm that ISIS2 3D back shape measurements are valid for assessment and follow up of patients with scoliosis. Three-dimensional back measurements were performed in Oxford. ISIS2 includes a camera/projector stand, patient stand with a reference plane, and Mac computer. Pixel size is approximately 0.5 mm with fringe frequency of approximately 0.16 fringes/mm ( approximately 6.5 mm/fringe). Clinical reports in pdf format are of coloured images with numerical values. Reports include a height map, contour plot, transverse section plots, coronal plot, sagittal sections and bilateral asymmetry maps. A total of 520 ISIS2 scans on 242 patients were performed from February 2006 to December 2007. There were 58 male patients (median age 16 years, SD 3.71, min 7, max 25) and 184 female patients (median age 14.5 years, SD 3.23, min 5, max 45). Average number of scans per patient was 2.01 with the range of 1-10 scans. Right sided thoracic curves were the most frequent pattern. The median values and 95% CI are reported of back length; pelvic rotation; flexion/extension; imbalance; lateral asymmetry; skin angle; kyphosis angle; lordosis angle; volumetric asymmetry. ISIS2 scoliosis measurements are non-invasive, low-cost, three-dimensional topographic back measurements which can be confidently used in scoliosis assessment and monitoring of curve progression