摆式波浪发电系统并网控制研究

发布时间：2018-04-10 09:09

本文选题：波浪能发电　切入点：直通物理分离型Z源逆变器　出处：《哈尔滨工业大学》2014年硕士论文

【摘要】：由于化石能源的过度使用，人类正面临着化石能源危机和环境恶化的双重压力，迫切需要开发可再生清洁能源，海洋波浪能因清洁可再生、对环境影响小等优点而倍受关注，波浪能发电成为研究热点。本文以海洋波浪能发电控制系统为研究对象，重点研究摆式波浪发电智能并网逆变器。首先，对6kW摆式波浪发电系统的组成装置及运行特点进行分析，基于共振原理及能量转换原理建立了摆式波浪发电机组的数学模型，主要包括波浪机模块、永磁发电机模块、传动系统及控制系统等几部分，并提出了变水室长度的控制策略，使系统实现了最大功率追踪控制。其次，针对传统Z源逆变器存在的不足，提出一种新型Z源拓扑结构——直通物理分离型Z源逆变器（IST-ZSI），介绍了IST-ZSI的工作原理及相关参数设计，并对系统进行仿真研究，仿真结果表明IST-ZSI不仅能有效降低启动冲击电流和电容电压应力，还将直通占空比的控制从物理结构上分离出来，实现升压因子和调制因子的解耦控制，获得较高的电压传输比和良好的动态性能。最后，，对摆式波浪发电系统进行并网研究，提出两种并网方案：即IST-ZSI特有的双闭环PI控制方案和直接电流下的单周控制并网方案。其中，双闭环PI并网方案解决了传统Z源逆变器只能通过间接测量阻抗网络电容电压的问题；单周控制的并网方案并网电流的谐波畸变率小，并网电流品质高。两种方案均表明直通物理分离型Z源并网逆变器启动冲击电流小、并网功率因数高、鲁棒性强、动态性能稳定，证明了两种控制方案的可行性和有效性。
[Abstract]:Wave energy generation has become a research hotspot.In this paper, the marine wave power generation control system is studied, focusing on the pendulum wave generation intelligent grid-connected inverter.First of all, the composition and operation characteristics of 6kW tilting wave generation system are analyzed. Based on the principle of resonance and energy conversion, the mathematical model of tilting wave generator set is established, which mainly includes wave generator module and permanent magnet generator module.Some parts such as transmission system and control system are put forward, and the control strategy of the length of the variable water chamber is put forward, which makes the system realize the maximum power tracking control.Secondly, aiming at the shortcomings of the traditional Z-source inverter, a new Z-source topology structure, the direct-through physical separation Z-source inverter, is proposed. The working principle of IST-ZSI and the design of related parameters are introduced, and the simulation of the system is carried out.The simulation results show that IST-ZSI can not only effectively reduce the starting impulse current and capacitor voltage stress, but also separate the direct duty cycle from the physical structure, and realize the decoupling control of the boost factor and the modulation factor.High voltage transfer ratio and good dynamic performance are obtained.Finally, two grid-connected schemes are put forward, that is, the dual closed loop Pi control scheme of IST-ZSI and the one-cycle control scheme under direct current.Among them, the double closed loop Pi grid-connected scheme solves the problem that the traditional Z-source inverter can only indirectly measure the capacitance voltage of the impedance network, and the single-cycle control scheme has low harmonic distortion rate and high quality of grid-connected current.Both schemes show that the direct physical separation Z-source grid-connected inverter has low starting impulse current, high grid-connected power factor, strong robustness and stable dynamic performance, which proves the feasibility and effectiveness of the two control schemes.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM612;P743.2

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