二极管箝位型多电平矩阵变换器拓扑和控制策略研究

For the fact that the conventional matrix converter topology is not suitable for high voltage and high power applications, this project is dedicated to investigate a diode-clamped multi-level matrix converter and its derived topologies, as well as the related modulation strategies, fault detection and fault-tolerant strategies. Based on the diode-clamped three-level matrix converter, other feasible multi-level topologies are derived by combining the multi-level inverter technology. Both the space vector modulation and the carrier-based modulation strategies for the proposed topologies are studied, and the intrinsic relationship between them are revealed. Then, by building the mathematical expressions between the modulation strategy and the related performance indexes, such as input and output power quality, system efficiency, output common-mode voltage, reactive power compensation capability, and device loss distribution, a single or multi-objective optimization modulation strategy will be presented consequently for specific demand. To ease the computational burden, a finite set based predictive control with reduced solution-space is proposed with the help of the modulation rules of matrix converter. To improve the reliability, robust fault detection strategies and fault-tolerant schemes for multi-level matrix converters are presented. Furthermore, the transient processes of the converter commutation loops are analyzed, which helps to optimize system design, and then a low-power lab prototype is set up to confirm the validity of the proposed topologies and algorithms. This project will provide the theoretical basis and key technology support for the development of multi-level matrix converter, expand the converter family of medium or high voltage frequency conversion, and offer new ideas for developing and utilizing the new energy, together with the energy-saving technologies.

针对传统矩阵变换器拓扑不适于中高压大功率应用的问题,本项目拟研究二极管箝位型多电平矩阵变换器及其衍生拓扑、调制策略和故障诊断与容错控制。以二极管箝位型三电平矩阵变换器为基础,推演其它拓扑结构。研究各拓扑的空间矢量调制和载波调制策略,并揭示二者内在联系；在建立调制策略与输入、输出电能质量，系统效率，共模电压，无功补偿能力和器件损耗分布等性能指标的数学关系的基础上，提出单目标或多目标优化调制策略。针对多电平矩阵变换器解空间大的问题，结合矩阵变换器的经验规则，提出基于简化解空间的有限集预测控制策略。针对系统可靠性问题，提出针对多电平矩阵变换器的鲁棒故障诊断和容错控制方法。研究电路换流环路及其暂态过程，优化系统设计，构建原型样机，验证方案的合理性。该项目的实施将为多电平矩阵变换器的发展提供理论基础和关键技术支持，为中高压变频家族增添新成员和注入新的活力，为新能源的开发以及节能技术的应用提供新思路。

本项目以二极管箝位型多电平矩阵变换器为对象，针对其工作原理及其衍生拓扑、调制策略、控制算法和故障容错控制等问题展开了研究。主要成果包括：1. 拓扑结构方面，提炼了二极管箝位型多电平矩阵变换器的拓扑构造规律，衍生设计出混合多电平矩阵变换器、简约型多电平矩阵变换器拓扑。2. 调制策略方面，提出基于反相层叠载波和同相载波两种多载波调制策略，通过分析得到调制策略与输出电流质量、开关损耗等指标的内在联系，还提出了一种抑制共模电压的优化调制策略；在空间矢量调制策略基础上，提出了六个新型零矢量，极大的抑制了矩阵变换器的共模电流；提出了抑制不平衡输入电压影响的数学构造调制策略。3. 控制算法方面，研究基于有限集模型预测控制的矩阵变换器控制方案，包括减少计算量、提高容错能力等。4. 故障容错控制方面，研究了基于有源共模电压注入的变换器开路故障检测方法，从二极管箝位型多电平矩阵变换器的结构、调制策略特点出发，研究了特定的故障诊断方法，通过探寻不同故障类型下的潜在容错回路，设计了整流级开关故障和逆变级开关开路故障的容错控制方法。研究成果发表学术SCI论文11篇，EI会议论文5篇，授权国家发明专利3项。