Estudo de um transformador eletrônico baseado em topologia de conversores modulares para aplicação em sistemas de microrredes

• Ano de defesa: 2018
• Autor(a) principal: Welbert Alves Rodrigues
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; Brasil; ENG - DEPARTAMENTO DE ENGENHARIA ELÉTRICA; Programa de Pós-Graduação em Engenharia Elétrica; UFMG
• Palavras-chave em Português: Transformador eletrônico; Microrredes; Topologias de conversores modulares; Controle adaptativo; Controle descentralizado; Estratégia de balanço de tensão e potência; Engenharia elétrica; Transformadores eletrônicos; Conversores de corrente elétrica
• Link de acesso: http://hdl.handle.net/1843/33443

Recently the Solid State Transformer (SST) has attracted much attention from the scientific community, due to its great potential of application in future intelligent grids. It is considered the key element to create the interface for connecting the microgrid system to the distribution network of the local utility. This enables plug-and-play integration with multiple sources of renewable energy, energy storage elements and DC distribution systems. Its main advantage over the conventional transformer is the substantial reduction in weight and volume. However, as it is an equipment essentially composed by power electronics is also able to actively act in the direction of improve the quality of grid power. In the present work a study and analysis of different topologies for the SST project is made, in which the topology of three converters connected in cascade is defined. The voltage levels of the distribution system are high, therefore it is proposed the application of modular converter structures for its design, which consists of the association of several modules with lower power converters. This structure has many advantages, however, component tolerances and incompatibilities between modules can lead to DC voltage unbalance and the uneven distribution of power flow drained by each module. In this context, the work proposes a strategy of decentralized control based on adaptive droop, capable of promoting the balance of voltage and power between the SST modules, without depending on a communication network. The behavior of the proposed strategy is evaluated through simulation of the SST switched model in MATLAB/Simulink. The strategy is also evaluated from the real-time simulation results obtained from a hardwarein-the-loop (HIL) based platform, which has the mathematical model of the converters x and the control loops embedded in a Digital Signal Processor (DSP).