【作者】 唐明；

【导师】 龚淑秋；

【作者基本信息】 沈阳工业大学 ， 电工理论与新技术， 2012， 硕士

【摘要】 太阳能作为一种可再生能源,是最有潜力的替代能源之一,是人类可以直接使用的清洁能源,而我国又是世界上太阳能资源最为丰富的国家之一,因此,在能源危机日益严重的今天,研究电力电子装置效率、改善其输出特性,开发和利用太阳能具有重大的战略意义。本文设计构建了太阳能并网逆变系统,并从最大功率点跟踪和逆变器的驱动、系统参数计算与控制器设计三个方面进行了深入研究。针对传统光伏逆变器体系结构存在着成本高、可靠性差和热斑现象等不足,本文提出了一种并联多支路的光伏逆变器结构,前级采用boost电路升压,可完成光伏电池最大功率点跟踪,后级逆变环节采用全桥逆变电路,输出级采用工频隔离变压器来实现电气隔离,从而实现了光伏电能输入,标准市电输出,克服了传统光伏逆变系统的一些不足。除此之外,本文还在如下环节做了较详细的研究:(1)DC/DC电路拓扑与控制器设计。主电路采用超级电容与boost升压电路组合的形式。以多晶硅太阳能电池板输出侧的电压与电流作为控制变量,在保证boost电路直流母线电压为500V的前提下,以最大功率作为的控制目标,采用变步长扰动观测算法实现最大功率点跟踪,极大限度的提高太阳能的利用率。(2)大功率DC/AC并网逆变器主电路拓扑及其控制器设计。DC/AC主电路采用电压型全桥逆变结构,功率器件使用IGBT模块或同等功率的IGBT单管,应用SPWM控制方式。采用dsPIC30F5015作为控制器主控芯片,完成了主控制器的设计,并对主逆变缓冲电路和输出侧滤波器进行了详细的参数计算。根据简单、鲁棒的原则,采用PID算法有效地稳定了直流母线电压同时调节了并网功率因数;采用被动孤岛检测法与主动孤岛检测法结合来防止孤岛效应。本文作者设计了10kW光伏并网逆变系统,并相应制作了小容量的逆变器闭环装置和大量仿真实验。通过对整个系统的理论分析和仿真结果证明,该系统设计方案是光伏并网发电领域的高效可行的较佳方案,具有不可估量的理论意义和经济意义。更多还原

【Abstract】 Solar energy as a renewable energy is the most promising substitute energy sources. Human can use it as a clean energy directly, and China who is the one of the countries has the most abundant solar energy resources, therefore, for the growing energy crisis today, studying the efficiency of power electronic devices, improving the output characteristics, and development and utilization of solar energy have significant strategic significance. A solar grid-system was designed and built in this paper, and the in-depth study and calculation were elaborated for the maximum power point tracking and inverter drives, system parameters and controller design in this paper.There are some lacks for the traditional architecture of the PV inverter, for example the high cost, poor reliability and hot-spot phenomena. A multi-branch centralized photovoltaic inverter structure was proposed in this paper and pre-boost circuit was used to increase the voltage, which can complete maximum power point tracking of photovoltaic cell. Full-bridge inverter circuit was used in after-class inverter and isolation transformer was used in output stage to achieve electrical isolation, so the input of solar energy and output of standard electricity were achieved which overcame some shortcomings of traditional PV inverter system. In addition, more detailed studies have been done for following areas in this paper:(1) DC/DC circuit topology and controller were designed. The main circuit was combined by super capacitor with boost circuit. The voltage and current of the output side of the polycrystalline silicon solar panel as the control variable to be used, the maximum power as the control objectives, at same time ensuring the boost DC bus voltage at 500V, the technique of variable step disturbance observer is used to achieve maximum power point tracking which improved the utilization of solar energy with maximum extent.(2) High-power DC/AC main circuit topology of grid-connected inverter and its controller were designed. Voltage full-bridge inverter structure was adopted in main DC/AC circuit; the same power IGBT module or single-tube was adopted in IGBT power devices and SPWM control was applied. dsPIC30F5015 chip was adopted in the master controller to complete the design, and the parameters of buffer and filter for output side were calculated in detail. According to a simple principles and robust principles, PID algorithm was adopted to stabilize the DC bus voltage effectively, and regulating the grid power factor; the way of combining passive way with active way was adopted to prevent island effect.A 10kW photovoltaic inverter system was designed in this paper. A small-capacity inverter device was manufactured and large numbers of closed-loop simulation were made. The whole system analysis and simulation results show that the solution is effective in the field of photovoltaic grid, and have practical theory significance and economic significance.更多还原