The research on supplying a power system with renewable energy sources has been going on for decades. In such researches, wind and solar energies are expected to dominate the total capacity. These types of renewable energy sources are interfaced with power electronics (converters) to the transmission grid. Presently, the power system dynamics are totally dependent on synchronous generators. The converters interfacing renewable energy sources are "Grid Feeding" converters. They are not designed to be able to form their own frequencies, so they use their PLLs (Phase Locked Loop) to track the frequency formed by the synchronous generators and inject the power generated from the renewable energy sources into the grid. This limitation makes it impossible for these intermittent energy sources to dominate a power network. For a network to be 100% supplied by renewable energies, converters that will form the frequency must be developed. They should be able to mimic the synchronous generators in forming the frequency locally for the other "Grid Feeding" converters in the system to track. Henceforth, the PE (Power Electronic) devices of this nature will be referred to as "Grid Forming" converters. In this regard, modeling of power network components and the converters, simulating and analyzing the stability of a network fed by 100% renewable energy sources interfaced with PE devices are carried out during this thesis work. These studied converters are finally tested on a model of the Irish Grid.
La ricerca sul modo di rifornire un sistema di alimentazione con fonti di energia rinnovabili è progredita per decenni. In tali studi ci si aspettava che l’energia solare e quella eolica avrebbero coperto pienamente il fabbisogno totale. Queste fonti rinnovabili sono connesse alla rete di trasmissione tramite l’elettronica di potenza (convertitori). Attualmente, le dinamiche dei sistemi di alimentazione sono completamente dipendenti dai generatori sincroni. I convertitori che si interfacciano alle fonti di energia rinnovabili vengono chiamati convertitori "Grid Feeding". Questi non possono generare le proprie frequenze, dunque usano i PLL (Phase Locked Loop) per inseguire la frequenza dei generatori sincroni e quindi iniettare la potenza generata dalle fonti rinnovabili nella rete. Tale limitazione rende impossibile a queste fonti energetiche intermittenti di dominare una rete elettrica. Affinché una rete sia fornita al 100% da energie rinnovabili, è necessario sviluppare convertitori in grado di generare la frequenza opportuna. Tali convertitori dovrebbero essere in grado di comportarsi come i generatori sincroni nella formazione della frequenza che verrà poi inseguita in modo locale dagli altri convertitori "Grid Feeding" nel sistema. Da qui in avanti, gli strumenti PE (Elettronica di Potenza) di questa natura saranno chiamati convertitori "Grid Forming". A tal fine, in questa tesi sono affrontate la modellizzazione delle componenti della rete elettrica e dei convertitori, la simulazione e l’analisi di stabilità di una rete alimentata al 100% da energie rinnovabili interfacciate con strumenti PE. Infine, i convertitori studiati sono testati su un modello della rete irlandese.
Modelling, simulation and stability analyses of a power system with 100% renewable energy sources interfaced with power electronics
BAH, EBRIMA A
2017/2018
Abstract
The research on supplying a power system with renewable energy sources has been going on for decades. In such researches, wind and solar energies are expected to dominate the total capacity. These types of renewable energy sources are interfaced with power electronics (converters) to the transmission grid. Presently, the power system dynamics are totally dependent on synchronous generators. The converters interfacing renewable energy sources are "Grid Feeding" converters. They are not designed to be able to form their own frequencies, so they use their PLLs (Phase Locked Loop) to track the frequency formed by the synchronous generators and inject the power generated from the renewable energy sources into the grid. This limitation makes it impossible for these intermittent energy sources to dominate a power network. For a network to be 100% supplied by renewable energies, converters that will form the frequency must be developed. They should be able to mimic the synchronous generators in forming the frequency locally for the other "Grid Feeding" converters in the system to track. Henceforth, the PE (Power Electronic) devices of this nature will be referred to as "Grid Forming" converters. In this regard, modeling of power network components and the converters, simulating and analyzing the stability of a network fed by 100% renewable energy sources interfaced with PE devices are carried out during this thesis work. These studied converters are finally tested on a model of the Irish Grid.| File | Dimensione | Formato | |
|---|---|---|---|
|
2018_10_Bah.pdf
accessibile in internet per tutti
Descrizione: Thesis text
Dimensione
2.62 MB
Formato
Adobe PDF
|
2.62 MB | Adobe PDF | Visualizza/Apri |
I documenti in POLITesi sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
https://hdl.handle.net/10589/142833