Regulacija napetosti v distribucijskih omrežjih s pomočjo SN/NN regulacijskih transformatorjev

MUHIČ, TADEJ (author), Blažič, Boštjan (mentor)

V magistrski nalogi je predstavljen način reševanja ohranjanja napetosti znotraj predpisanih meja v razdelilnih omrežjih zaradi težav, ki so nastale kot posledica vse večjega števila implementiranih razpršenih virov v omrežje. Izdelali smo regulacijski algoritem, ki je sposoben poleg VN/SN regulacijskega transformatorja regulirati tudi SN/NN regulacijske transformatorje. Za simulacijsko orodje smo uporabili odprtokodni program OpenDSS, katerega smo za potrebe lažje analize, obdelave ter grafičnega prikaza podatkov povezali s programskim paketom Matlab. Na začetku dela sta predstavljena vpliv razpršene proizvodnje na napetostni profil ter distribucijski transformator s pripadajočimi razvojnimi trendi. V nadaljevanju je opisan način definiranja omrežja v simulacijskem orodju, na katerem smo simulirali pretoke moči skozi celoten dan. V prvi fazi smo analizirali model osnovnega stanja, kjer v omrežju ni prisotnih razpršenih virov in je prisotna klasična regulacija napetosti. V omrežje smo v naslednji fazi vključili razpršene vire in spremljali odziv omrežja preko potekov napetosti, moči, izgub, padcev napetosti skozi posamezni element ipn. Klasično metodo regulacije napetosti smo nadgradili z integracijo regulacijskih distribucijskih SN/NN transformatorjev ter izdelali algoritem za avtomatsko regulacijo napetosti pod obremenitvijo. Regulacijski distribucijski transformatorji imajo za razliko od klasične metode, kjer se uporablja nastavljivi fiksni odcep, spodobnost avtomatske regulacije regulacijskih odcepov pod obremenitvijo. Regulacijski algoritem za delovanje potrebuje podatke o referenčni merjeni točki. Raziskali smo klasični ter centralni način delovanja regulacijskega algoritma, kjer uporabljamo različne merjene točke. V zadnji fazi dela smo pogledali, kolikšno je maksimalno število integriranih razpršenih virov v NN omrežje pri različnih načinih regulacije. Ker je vpliv integracije razpršenih virov v omrežje zelo odvisen od lokacije integracije in obremenitve omrežja, smo simulacije izvajali iterativno. Iz rezultatov iteracijske metode smo na koncu izračunali povprečje glede na 90 % uspešnih rezultatov.

• Language: Slovenian
• Keywords: razpršeni viri, regulacija napetosti, napetostni profil, regulacijski transformator
• Work type: Master's thesis/paper
• Organization: FE - Faculty of Electrical Engineering
• Year: 2016
• PID: 20.500.12556/RUL-81549
• Publication date in RUL: 12.04.2016

Secondary language

• Language: English
• Title: Voltage control in distribution networks with voltage-regulating MV/LV transformers

Abstract

This Master's thesis presents a solution to maintaining the voltage in distribution networks within the prescribed ranges. The regulation problem emerged because of the ever-increasing number of renewable energy sources implemented into distribution networks. We created an algorithm capable of regulating both the HV/MV regulatory transformers and the MV/LV regulatory transformers. As our simulation tool, we used the open-coded programme OpenDSS, and connected it to the programme pack Matlab so that we could more easily analyse, process and graphically present the data. Firstly, we presented the influence of distributed generation on the voltage profile, the distributional transformer and its evolutionary trends. Furthermore, we discussed the way to define the network in the simulation tool, which we used to simulate the power flow during the whole day. In the first phase, we analysed the primary state module, where there is no renewable energy sources present and the regulation network is in the classic mode. In the next phase, we introduced the renewable energy sources in the network and observed how the network reacted (the voltage flow, power, losses, drops in the voltage in the presence of a particular element etc.). We upgraded the classic voltage regulation method by integrating the regulatory distributional MV/LV transformers. We also created an algorithm to automatically regulate the voltage when loaded. In contrast to the classic method where the adjustable off load tap change is used, the regulatory distributional transformers use the automatic on load tap change. To function, the regulatory algorithm requires data about the referential point of measure. We explored both the classic and the central operational modes of the regulation algorithm, where we use different points of measure. In the last phase, we evaluated the maximal number of integrated renewable energy sources in the LV network considering various regulatory modes. Because the influence of the integration of renewable energy sources in the distribution networks heavily depends on the location of integration and the network load, we implemented the simulations iteratively. We took the average of the total results given by the iteration method based on the 90% of successful results.

• Keywords: renewable energy sources, voltage regulation, voltage profile, regulatory transformer