Power Quality Improvement of Smart Microgrids

智能微电网是将可再生能源（RES）集成到公用电网并允许客户参与能源企业的有前途的解决方案。在不久的将来，智能微电网将为客户提供负担得起的电力，并为依赖无排放能源铺平道路。智能微电网通常被分类为交流、直流和混合交流/直流，并且提供优于传统电力系统的若干优点，例如，它们提供了更高的可靠性、安全性、效率，允许通过分布式发电（DG）单元开发可再生能源，减少损失，并且有利于健康、气候和世界经济。尽管它们具有优势，但存在与智能微电网的有效设计和使用相关的若干技术挑战。一些主要的挑战是电力质量（PQ）退化的公用电网，和稳定性问题，由于间歇性的RES和负载变化。此外，配电网中非线性和不平衡负载的扩散导致智能微电网的许多PQ和稳定性问题。PQ不佳会给公用电网和消费者带来许多问题，例如，电力损失、敏感设备故障、电力中断、负载性能差、安全问题，并导致巨大的成本。例如，EPRI-CEIDS进行的一项调查显示，由于各种PQ问题，北美经济每年损失超过240亿美元。 在这个发现计划中，我们的目标是克服与交流和混合AC/DC微电网的PQ和稳定性相关的一些挑战。具体而言，在建议的研究中，我们会处理以下工作： ·提出高性能鲁棒分散控制器，用于具有电子耦合和直接耦合的基于机器的DG单元的交流微电网的PQ改善， ·为基于并网变流器的DG单元开发多功能控制策略，以补偿非整数次谐波， ·提出鲁棒控制器以在存在不确定非线性和/或不平衡负载的情况下提高孤岛混合AC/DC微电网的鲁棒稳定性和PQ，以及 ·为并网混合AC/DC微电网的互联变换器设计非线性鲁棒控制器，以保证电压稳定性并改善PQ。 拟议中的发现计划将有助于可再生能源和智能微电网技术的发展。此外，通过拟议的计划，我们将有助于培训HQP这是在加拿大工业和学术界的高需求。

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.