Simulation and hardware-in-the-loop evaluation of dual boost converter with shared transformer - part A

• Main Author: Seetoh, Winston Zit Yang
• Other Authors: Zhang Xinan
• Format: Final Year Project
• Language: English
• Published: 2018
• Subjects: DRNTU::Engineering::Electrical and electronic engineering
• Online Access: http://hdl.handle.net/10356/76306
• Institution: Nanyang Technological University

This report presents the study of Advanced Control Systems for Dual Boost Converter with Shared Transformer. The single-inductor-single-input-dual-output (SISIDO) buck converters (DC-DC) in this report adopts a single inductor/transformer i.e. the output loads share a single inductor/transformer. Using only one inductor/transformer leads to reduction of component number, cost and circuit size when compared with conventional multi-load system which uses many single-input-single-output (SISO) converters. In addition, the use of single inductor/transformer reduces electromagnetic interference (EMI) problem. In multi-load system with many SISO converters, EMI problem can be serious if the number of inductors/transformers are significant. The critical issue of adopting one inductor/transformer is cross regulation i.e. mutual interference among the loads. After driving one load, residual energy remains in the shared transformer/inductor. When driving the next load, residual energy from the previous load will be delivered. Thus, the previous load causes interference to the next load. Hence, the loads are not supplied with their respective demands but with mismatching energy to their individual demands. To minimise cross regulation significantly, advanced control system with dynamic and fast response capability is needed to provide to the multiple loads their respective power demand basing on real-time data. It has the capability to ensure the outputs track closely the references. Model predictive current control method (MPCC) and model predictive voltage control method (MPVC) are utilised to significantly minimise the cross-regulation issue. Charge equalization method for charging batteries (series connected) in electric vehicles (EVs) using the MPCC method is studied. Imbalance of EVs batteries due to manufacturing differences shorten battery cells’ lifetime. The lifetime of batteries cells can be extended by charging equalisation. To verify, simulation of the SI-SIDO buck converter with MPVC method are conducted. MATLAB/Simulink simulation results shows that the MPVC method regulates the output voltages to track the preset voltage references closely and the voltage ripples are controlled within the tolerate range. The cross regulation is significantly reduced. Although hardware is not part of the project scope, the hardware circuits were successfully built and tested.