混合式户用光伏逆变器设计

发布时间：2018-07-05 13:52

本文选题：虚拟磁链预测模型 + 并网逆变器　；参考：《安徽工程大学》2017年硕士论文

【摘要】：光伏是新能源供给线的主干力量。逆变器是新能源发电的重要环节。光伏逆变器则是光伏作为新能源供给电能的关键设备,它是落实到实际事物的变流装置。光伏逆变器以其安装方式简易、能源获取便捷等特点,在新能源市场中大放光彩,促进了光伏逆变器市场蓬勃发展。单一的逆变器并不能克服风、光、潮汐、地热等间歇性能源的局限性。为迎合市场需求的不断变化,克服新能源的缺点。研究混合式逆变成为光伏逆变较为主要的研究方向之一。混合式光伏逆变器即是新能源应用于实践的变流装置,也不仅限于变流装置,它是新一代的能源管理器。新能源虽然无污染,资源储备量大,但其独特的间歇性和不稳定性,在工程实践中高效利用并非易事。本文以中小功率的混合式逆变器为研究内容,重点工作放在系统结构的分析与设计、系统运行模式剖析与优化、控制策略的介绍与改进和涉及电路参数设计的系统控制稳定性分析。首先,通过文献检索与市场调查分析市场上有的、文献提及的逆变器系统结构原理,分析其结构特点,在特定的工况下分析该结构的优缺点。针对非计划离网提出基于直流母线结构模式的改进型结构模式。分析该结构模式对于非计划离网的应对机制与其结构所确立的优点,提出基于分时双向定母线电压的运行模式,改善系统受外电网变化而带来的波动,并利用Simulink搭建仿真模型,验证该运行模式的可行性;第二,针对DC/DC功能模块电路的拓扑结构进行系统建模,利用Matlab工具平台,分析涉及具体参数设计时系统的稳定性,根据分析结果选择性的在控制环节中加入PID稳定性控制环节,通过Simulink仿真,验证基于电池充放电的恒流恒压控制;第三,根据文献检索分析现有逆变功能模块并网控制策略,阶梯式介绍电压矢量控制、功率直接控制和虚拟磁链技术的引入,详细剖析各并网控制策略原理,提出各控制策略在采样与控制环延时存在延时的共同缺点,在此基础上提出基于卡尔曼滤波的改进方案优化控制性能。最后在上述理论的基础上,设计搭建10kW混合式逆变器实验平台。通过实验与仿真平台对混合式逆变器的各项性能指标进行测试:双向DC/DC模块的充放电控制;多直流母线的电压稳定性控制;特定非计划离网工况下的稳定性控制等做了不同工况的实验研究。在非计划离网工况下,二级直流母线稳定性相对提高。分析实验所得数据,验证了本方案的可行性。
[Abstract]:Photovoltaic is the backbone of the new energy supply line. Inverter is an important link in new energy generation. Photovoltaic inverter is the key equipment of photovoltaic power supply as new energy, and it is the conversion device to realize the actual things. Photovoltaic inverter (PV) has the advantages of simple installation and convenient access to energy, which has greatly glowed in the new energy market and promoted the vigorous development of photovoltaic inverter market. A single inverter cannot overcome the limitations of intermittent energy such as wind, light, tide, and geothermal. In order to meet the changing needs of the market, overcome the shortcomings of new energy. The research of hybrid inverter has become one of the main research directions of photovoltaic inverter. Hybrid photovoltaic inverter is a new generation of energy management device, which is not only limited to converters, but also used in practice. Although new energy is pollution-free and has a large resource reserve, its unique intermittency and instability are not easy to utilize efficiently in engineering practice. This paper focuses on the analysis and design of the system structure, the analysis and optimization of the system operation mode, taking the medium and small power hybrid inverter as the research content. The introduction and improvement of control strategy and the analysis of system control stability involving circuit parameter design. Firstly, the structure principle of the inverter system mentioned in the literature is analyzed by literature retrieval and market survey, and the advantages and disadvantages of the inverter system are analyzed under the specific working conditions. An improved DC bus structure model is proposed for unplanned off-grid. Based on the analysis of the response mechanism of the structure to unplanned off-grid and the advantages established by its structure, the operation mode based on time-sharing bi-directional fixed bus voltage is put forward to improve the fluctuation of the system caused by the change of external power network, and the simulation model is built by using Simulink. The feasibility of the operation mode is verified. Secondly, the system modeling of the DC / DC functional module circuit topology is carried out, and the stability of the system is analyzed by using Matlab tool platform, which involves the design of specific parameters. According to the results of the analysis, the pid stability control link is added selectively to the control link. Through Simulink simulation, the constant current and constant voltage control based on battery charge and discharge is verified. Thirdly, according to the literature retrieval, the existing inverter function module grid-connected control strategy is analyzed. This paper introduces the introduction of voltage vector control, direct power control and virtual flux linkage technology, analyzes the principle of each grid-connected control strategy in detail, and points out the common shortcomings of each control strategy in the delay of sampling and control loop. On this basis, an improved scheme based on Kalman filter is proposed to optimize control performance. Finally, on the basis of the above theory, a 10 kW hybrid inverter experimental platform is designed and built. The performance indexes of hybrid inverter are tested by experiment and simulation platform: charge and discharge control of bi-directional DC / DC module voltage stability control of multi-DC bus; The stability control under the specific off-grid condition is studied in different working conditions. Under unplanned off-grid condition, the stability of two stage DC bus is relatively improved. The feasibility of the scheme is verified by analyzing the experimental data.
【学位授予单位】：安徽工程大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM464

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