الفهرس 
Chapter 1 INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The key role of distribution networks is to provide electricity to consumers in
an adequate and uninterrupted way. Most of these networks suffer from various
technical and economic challenges. High power losses, high voltage deviation,
poor power factor, reactive power shortage, lines congestion and high expenses
represent some of these challenges. Power system research reveals that the power
loss dissipated by distribution networks accounts for about 20% in developing
countries, while it is less than 10% in developed countries. For achieving
enhanced performance and energy savings of distribution networks, it is necessary
to satisfy the power loss limits.
For this target, Fixed Capacitors (FCs), Switched Capacitors (SCs),
Automatic Voltage Regulators (AVRs) and system reconfiguration are
traditionally used. Also, Flexible Alternating Current Transmission systems
(FACTS) represent advanced solutions to the problem of reactive power
compensation, especially the Static VAR Compensators devices (SVCs) as they
represent the most common FACTS devices. Accompanied to this, Distributed
Generations (DGs) from renewable and non-renewable sources are on the rise.
Therefore, this thesis handles the reactive power compensation via FCs and SVCs
with penetration of DGs to improve the performance of distribution networks.
First of all, this thesis proposes a powerful strategy for assigning the optimal
allocations of FCs and Hydrogen-based Fuel Cells (HFCs) in realistic distribution
networks. Various optimizers such as; particle swarm optimizer technique, basic
grey wolf optimizer technique and improved grey wolf technique merged with
Analytical Hierarchical Process (AHP) are presented for handling this problem.
Furthermore, the utilized approaches accomplish multi-objectives such as;
minimizing power loss, minimizing total investment costs, reducing voltage
deviation compared to the reference voltage and provides load balance to the system. These objectives are related to some operational and planning restrictions
which judge the distribution network performance. Power balance, HFCs capacity,
FCs capacity, bus voltage limits and lines thermal limits are some of these
constraints.
After that, this thesis also proposes a robust strategy to optimize the
performance of medium voltage distribution networks via the optimal coordination
between HFCs and SVC devices. In order to investigate the influences of loading
variations, different regular loadings are further combined. Moreover, two realworld
distribution networks are employed to prove the capability of the IGWA
technique. The results obtained have shown that IGWA technique is more efficient
and robust compared to other techniques.