三电平光伏逆变电源混合调制的一体化控制研究

项目名称： 三电平光伏逆变电源混合调制的一体化控制研究

项目编号： No.51507137

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 电工技术

项目作者： 安少亮

作者单位： 西安理工大学

项目金额： 22万元

中文摘要： 当前，我国光伏并网逆变器在基本理论和实用技术方面已经取得可喜成绩，但是，在高效率、高性能绿色环保型光伏并网逆变器上，与欧洲、美国等发达国家仍有一定差距。本课题以非隔离三电平三相光伏并网逆变器为研究对象，重点研究基于(5+7)段混合调制的一体化控制。采用数学分析法，定量描述新型(5+7)段混合调制策略在三电平逆变器上的线性调制范围、谐波畸变率、开关损耗性能，并分别采用载波法与矢量法实现(5+7)段混合调制，对比该混合调制相对于传统5段式不连续调制、7段式连续调制在控制性能上的差异；进一步，以开关损耗降低与共模电流抑制为目标，通过分析开关损耗、共模电流、中点电压、谐波畸变与(5+7)段混合调制之间的行为特征与耦合关系，揭示其内在规律及物理含义，建立统一化数学模型，得出基于混合调制，同时考虑开关损耗、共模电流、中点电压、谐波畸变综合优化的一体化控制体系。

中文关键词： 三相逆变器；并网运行；并网变流器；并网控制

英文摘要： At present, China's photo-voltaic grid connected inverters have made gratifying achievements in basic theories and practical technologies. However, in high efficiency, high performance and green environmental protection type for photo-voltaic grid connected inverters, there is still a certain gap between developed countries such as Europe, America etc..A non-isolated three-level three-phase photo-voltaic grid inverter is investigated in the subject，focusing on (5+7)-segment mixed modulation and integrated control. Using mathematical analysis, performances such as linear modulation range, harmonic distortion,switching loss are quantitatively described based on the new (5+7)-segment mixed modulation strategy in the three-level inverter. Carrier wave method and space voltage vector method are both utilized to contrast their differences in control performances. Furthermore, in order to reduce switching losses and restrain common mode currents, the behavioral characteristics and the coupling relationship are analyzed among with switching losses, common mode currents, neutral point voltages, harmonic distortion and (5+7)-segment mixed modulation. The inherent laws and physical meaning are revealed. A unified mathematical model is established. An integrated control system and comprehensive optimization is derived based on mixed modulation, taking into account the switching losses, the common mode current, the midpoint voltage and harmonic distortion.

英文关键词： three phase inverter;grid-connected running;grid-connected converter;grid-connected control