Title Statistički pristup u analizi stabilnosti napona visokonaponskog prijenosnog sustava Title (english) Voltage stability steady state analysis of highvoltage transmission system Author Igor Ivanković Mentor Ante Marušić (mentor)Committee member Sejid Tešnjak (predsjednik povjerenstva)Committee member Ante Marušić (član povjerenstva)Committee member Matislav Majstrović (član povjerenstva)Committee member Tomislav Tomiša (član povjerenstva)Granter University of Zagreb Defense date and country 2005-07-08, Croatia Scientific / art field, TECHNICAL SCIENCES Universal decimal classificationUDC ) 621.3 - Electrical engineering Abstract U ovom radu rješavana je problematika naponske stabilnosti u visokonaponskom prijenosnom sustavu, u svjetlu novonastalog okruženja za elektroprivredana poduzeća. Apostrofirati će se dva glavna smjer, to je potreba za povećanjem proizvodnih i prijenosnih kapaciteta, te proces deregulacije i privatizacije elektroprivrede. Sagledavali su se uzroci koji mogu dovesti do nastanka naponske nestabilnosti u EES-u. Oni su detaljno rasčlanjenji po svim dijelovima i uređajima EES-a, kao i preventivne i korektivne akcije u tijeku planiranja i vođenja, te posebno mjere koje se moraju poduzimati u takvim slučajevima. Utjecaj dinamičke i statičke rezerve jalove snage, automatske regulacije napona i karakteristika tereta, igraju važnu ulogu u dinamici odvijanja naponskog sloma. U radu se posebna pažnja posvetila radu automatske regulacije napona kao i karakteristika tereta u statičkom pristupu. Početna analiza pretpostavlja proračune koji se rade u tu svrhu. Prvi od koraka koje je potrebno obavezno napraviti su analize tokova snaga u svrhu analize kritičnih uklopnih stanja po pitanju tereta i tranzita. Ovdje su analizirane upravo takve situacije na konkretnom elektroenergetskom sustavu sjeverozapadne Hrvatske. Proračunate su situacije sa specifičnim uklopnim stanjima koja su zanimljiva po pitanju naponske nestabilnosti. Na tom konkretnom modelu sagledan je utjecaj automatske regulacije napona, kao i utjecaj karakteristika tereta u tim proračunima. U trenutcima nastanka početne naponske nestabilnosti akcije blokade rada regulacijske sklopke, odnosno njeno reverziranje i karakteristika tereta koje tada pretežito ima obilježje konstantne impedancije, imaju pozitivan utjecaj na zaustavljanje degradacije karakteristika sistema. Ali, one ne mogu posve zaustaviti naponski kolaps, nego samo daju određene vrijeme za djelovanje korektivnih mjera koje se primjenjuju u tim slučajevima. Stoga je potrebno poboljšati postojeće stanje. Treba aktivirati mogućnost centralne ili automatske blokade rada automatske regulacije napona, te je potrebno aktivirati mogućnost reverziranja rada regulacijske sklopke. Neophodno je istraživanje u smjeru modeliranja i definiranja karakteristika tereta u našem elektroenergetskom sistemu. Druge mjere koje se trebaju implementirati u upotrebu, jesu mjere podnaponskog rasterećenja sustava i proširenja postojećeg sistemskog nadzora i sistemske zaštite. Proračuni tokova snaga obavljaju se danas na više načina, klasične metode Gauss-Seidl i Newton-Raphson su u širokoj upotrebi i njihove razne varijante i modifikacije. Zbog prevladavanja problema singularnosti Jacobijeve matrice razvijene su i druge, poput kontinuiranih tokova snaga. Posebna pažnja se posvećuje analizi Jacobijeve matrice, čiji rezultati analize omogućuju dobivanje pokazatelja naponske stabilnosti i nestabilnosti.
Abstract (english) This thesis deals with problems related to voltage stability in the highvoltage transmission system, specially from the aspect of new transitions of utilities. Two main cours will be highlited, first one is the demand for the bigger generations and transmissions capacities, and second one is the permanent process of deregulations and privatizing process. The causes of voltage instability were analyzing. These causes can have a very strong influence at each part and device in the power system, also during the process of planning and operating the system preventive and corrective actions have to be taking. This special measurement must be implementing because of alleviation the negative consequence of voltage instability. Three main factors are dominant in the time frame of dynamics of voltage stability, dynamics, and static reserve of reactive power, voltage automatic regulation and the load characteristics. Steady state approach in the thesis attention has focused on the voltage regulation and load characteristics. In the very beginning of each analysis has made an initial calculation. First step is analysis of result of load flow calculation, considering the wide spread conditions of the power system, during the normal and contingency state. Here have analysis of these terms on northwest part of Croatian power system. Special conditions for the initial voltage instability states have calculated. These particular model of power system have used to perform and analysis influence of automatic voltage regulator and load characteristics. In the very beginning of the voltage instability, voltage regulator action like blocking and tap reversing together with load characteristics who are dominantly have constant impedance characteristic, have very positive influence to decelerating the speed of degradation system characteristics. In the other words, these actions are not enough to stop voltage collapse; they are only giving some time for the corrective actions have been taking. In the whole system must be reconsidered the conditions. On the system level must be realize central or automatics blocking voltage regulation, together with possibilities of tap reversing. Future work has to take investigation of load modeling with new load characteristics definitions in our power system. This is not enough for complete alleviation of voltage instability problems. In the system has to be implemented the undervoltage shedding and upgrade exist wide area monitoring and wide area protection. Today load flow calculations have to been perform on the classical way with Gauss-Seidel and Newton-Raphson technique, together with many variation and modifications of these technique. To avoid the problem of singularity of Jacobian matrix other methods has developing like a continuation power flow. Special attention has to be give to Jacobian matrix, the result of the analysis can give to us very useful criteria for the voltage sensitivity index.
Keywords
Elektroenergetski sustav
stabilnost napona
slom napona
visokonaponska prijenosna mreža
jalova snaga
zaštita od naponskog sloma
Keywords (english)
Electric power system
Voltage stability
voltage collapse
HV transmission network
reactive power
protection against voltage collapse
Language croatian URN:NBN urn:nbn:hr:168:959509 Study programme Title: Postgraduate master programme in electrical engineering Type of resource Text File origin Born digital Access conditions Closed access Terms of use Created on 2019-07-04 07:09:54
