Power Quality Improvement of Smart Microgrids

点击翻译按钮获取中文摘要

Smart microgrids are promising solutions to integrate renewable energy sources (RESs) into the utility grid and allow the customers to participate in the energy enterprise. In the near future, smart microgrids will contribute to affordable electricity for customers, and will pave the path to rely on an emission-free form of energy. Smart microgrids are usually categorized into ac, dc and hybrid ac/dc, and provide several advantages over conventional power systems, e.g., they provide increased reliability, security, efficiency, allow the exploitation of the RESs through distributed generation (DG) units, reduce losses, and are beneficial for health, the climate, and the world economy. Despite their advantages, there exist several technical challenges associated with the efficient design and use of smart microgrids. Some of the main challenges are power quality (PQ) degradation of the utility grid, and stability issues due to the intermittent nature of the RESs and load variations. Moreover, the proliferation of nonlinear and unbalanced loads in distribution networks results in a number of PQ and stability problems for smart microgrids. Poor PQ results in a multitude of problems for both utility grid and consumers, e.g., power losses, malfunction of sensitive equipment, power interruptions, poor performance of the loads, safety issues, and incur huge costs. For example, a survey conducted by EPRI-CEIDS shows that the North American economy loses more than 24 billion dollars per year due to various PQ problems. ***In this Discovery program, we aim to overcome some of the challenges associated with PQ and stability of ac and hybrid ac/dc microgrids. More specifically, in the proposed research, we will tackle the following tasks:*** Proposing high performance robust decentralized controllers for PQ improvement of ac microgrids with electronically- and directly-coupled machine-based DG units,*** Developing multifunctional control strategies for grid-connected converter-based DG units in order to compensate for non-integer harmonics,*** Proposing robust controllers to improve robust stability and PQ of islanded hybrid ac/dc microgrids in the presence of uncertain nonlinear and/or unbalanced loads, and*** Designing nonlinear robust controllers for the interlinking converters of a grid-connected hybrid ac/dc microgrid to guarantee voltage stability and improve PQ. ***The proposed Discovery program will contribute to the development of renewable energy and smart microgrids technologies. Moreover, through the proposed program, we will contribute to the training of HQP which are in high demand by Canadian industries and academia.