【作者】 贾儒彬；

【导师】 王玉斌；

【作者基本信息】 山东大学 ， 电力电子与电力传动， 2010， 硕士

【摘要】 太阳能是一种清洁高效的能源,以其无污染、可再生、不受地域限制等优点,正得到迅速的推广与应用。在世界能源危机和环境恶化日益严重的今天,更好的开发利用太阳能等可再生能源以实现可持续发展变得至关重要。随着光伏电池和电力电子技术的不断发展,太阳能光伏发电已成为新能源利用的主要形式之一。太阳能光伏发电系统主要由太阳能电池板、DC/DC变换器、逆变器等几部分组成。现在的DC/DC变换器主要以单相全桥拓扑的形式为主。虽然也有一些多相变换器,但是其主要应用于高电压小电流输入的场合,并且这些变换器的设备特性并不适合低电压大电流输入的场合,例如太阳能光伏发电。基于此本文选择分析研究了一种新颖的能应用于太阳能光伏发电的三相六桥臂DC/DC变换器。其通过多相交错并联而不是多个器件并联的方式来提高变换器的功率等级,并且其变压器为△-Y连接方式,从而能够升高输出电压,减小变压器的绕组比例。同时因为交错并联的控制方式,其经过全桥整流后的输出电压的纹波频率是开关频率的6倍,从而能够减小输出滤波器的尺寸。本文对这种DC/DC变换器进行了建模分析,并得到控制角度α到输出电压Vout之间的传递函数。本文分析了单电压环控制方式,电压外环电流内环控制方式及带电流截止负反馈电压环控制方式的参数设计。并用PSIM仿真软件对这三种控制方式下的电路进行仿真,而且仿真分析了在带逆变器负载的情况下,带电流截止负反馈电压环控制方式下,DC/DC变换器的输出电压波动情况。最后根据对系统参数的设计及仿真结果的分析,对DC/DC变换器的部分硬件电路进行了设计。更多还原

【Abstract】 Solar energy is one of clean, highly-efficient resources. It is pollution-free, renewable and not limited by regions, so it has been quickly popularized and applied. Because of the world energy crisis and environmental deterioration, it is vital to develop and utilize the renewable sources (for example:solar energy) for sustainable development. With the development of solar cell and power electronics, photovoltaic power generation has become to a main way of utilizing new energy resource. Photovoltaic system consists of solar cell, dc/dc converter and inverter.At present, the single-phase full-bridge converter is the dominant topology in high power dc/dc applications. Although multiphase converters have been proposed, most of them are used in high input-voltage, low input-current systems, which is not suitable for a low voltage, high current system such as photovoltaic system. This paper analyzes a novel three-phase six-leg dc/dc power converter used in low input-voltage, high input-current system. Power rating of the converter is increased by multiphase interleaving, not by multiple devices in parallel, and its transformer isΔ-Y connection, so it can double the output voltage and lower the turns-ratio of transformer. Because of the interleaved control, the frequency of output voltage is six times higher than the frequency of switches, so the size of output filter can be reduced.This dissertation also analyzes the model of the dc/dc converter and gets the transfer function between control degree a and output voltage Vout. This paper discusses the parameters design of single voltage loop control, inner current loop-outer voltage loop control and voltage loop with current cut-off feedback, and simulates the circuit of three control methods by PSIM software. the dc/dc converter under inverter-load condition is also simulated, through control method of voltage loop with current cut-off feedback. Finally, according to parameter design and simulation results, several parts of the hardware designs are analyzed更多还原