Energy storage system based on PMP21529 buck-boost Bi-directional DC-DC converter

• Main Author: Yan, Shunyao
• Other Authors: Muhammad Faeyz Karim
• Format: Thesis-Master by Coursework
• Language: English
• Published: Nanyang Technological University 2022
• Subjects: Engineering::Electrical and electronic engineering::Power electronics
• Online Access: https://hdl.handle.net/10356/159166
• Institution: Nanyang Technological University

In recent years, with the continuous development of renewable energy and the promotion of distributed power, modern power grids have put forward high stability and high flexibility requirements for power quality. The advantage of power electronics is that it can reduce power losses by improving power generation, transmission, and distribution sections, increasing efficiency; therefore, it is widely used nowadays. New energy distributed energy storage is also a boom in recent years. In Singapore, solar photovoltaics are widely used. Under this condition, through DC-DC converters, energy storage systems can undertake energy storage and backup functions; typical applications include battery backup units and local energy storage systems. A DC-DC bi-directional buck-boost converter can step up and step down the dc voltage of input, so it is wildly used in energy storage systems. PMP 21529 is a four-switch bi-directional DC-DC buck-boost converter with high efficiency, when the input dc power bus is powered normally, the converter can charge the lithium battery in buck or boost mode, when the input power bus fails, or the power is cut off, the battery can be used as a backup system to supply power to the dc bus, which improves the power system's reliability. The PID compensator is also an essential part of DC-DC converter closed-loop control. Using the PID compensator, the phase margin and gain margin can be increased to improve the stability of the converter system. In addition, closed-loop control allows the system to automatically adjust the duty ratio based on the difference between the output voltage and the input voltage. This dissertation is based on PMP 21529 as the research project aiming to investigate whether it can be used as a buck-boost converter for energy storage systems. This dissertation analyzes the working principles of the UCD3138 digital controller and does simulations and tests on PMP21529 according to the schematic diagram.