چكيده به لاتين
Along with the remarkable growth of power electronics in recent decades and its increasing
usage, DC-DC converters have also found special application and importance. In recent years,
the topic of energy management in the railway, which is considered as an important and heavy
load for the main network, has received much attention. Using efficient and suitable converters
is one of the most important parts for the implementation of the proposed energy management.
In this project, a DC-DC converter is proposed to run a system with a PV source, energy storage
system (battery) and load. First, an overview of the proposed structures for multi-port DC-DC
converters is provided. In recent studies, various aspects of these converters such as buck, boost
or buck-boost performance, bidirectional capability, number of elements (switches and power
diodes, inductors, capacitors, etc.), voltage stress and current flow on the switches and diodes
and the efficiency of the converter have been investigated.
According to the studies, it is desirable to design and select an appropriate structure that has
acceptable performance in various aspects and can be implemented in reality. One of the most
important points in the design of the project is soft switching and system efficiency. For this
purpose, resonant structures have been considered to minimize switching losses that increase
at high frequencies using the features of resonant LLC converters. Afterward, the mathematical
model of the proposed structure has been calculated and presented for the control section. Then,
to validate the accuracy of the converter performance and the obtained equations, the
simulation of the system has been performed in MATLAB software. By using the simulation
results some modifications have been made to improve the converter performance. Finally, a
three-port LLC converter has been implemented, which has integrated the input converter,
energy storage converter (battery) and load converter, and has been used as an integrated
converter. Pulse-width modulation and phase shift control methods are used for the proposed
topology. With different operating modes, this structure manages the energy transferred
between the input, storage and load ports. Due to the use of the LLC converter, it can provide
soft switching for all switches and diodes. The proposed structure is suitable for the
management and control of renewable energy along with the energy storage system.
