【作者】 王光旭；

【导师】 沈运先；

【作者基本信息】 中国舰船研究院 ， 通信与信息系统， 2011， 硕士

【摘要】 太阳能作为一种清洁、高效和可持续发展的新能源,日益引起了各国的广泛重视。光伏并网发电技术代表了太阳能发电技术的发展方向。本文重点研究了太阳能发电系统中的关键部件:光伏并网逆变器,其作用:一是使光伏阵列工作在最大功率输出状态;二是将光伏阵列产生的直流电能转换为交流电能,并且使逆变输出电流与电网电压保吃同步。本文首先介绍了太阳能电池的电气特性及最大功率输出点的跟踪方法,接着重点介绍了三电平逆变电路的结构,比较了逆变电路两种调制方法,重点分析了空间矢量调制的原理与实现步骤。本文紧接着介绍了基于瞬时无功功率理论的三相电网的锁相方法,针对三相电网不平衡情况下,传统软件锁相算法的不足,介绍了两种改进措施。建立了光伏并网逆变器在不同坐标系下的数学模型,重点研究了电压外环电流内环的双闭环矢量控制策略,以典型控制系统设计与工程经验整定相结合的办法解决比例与积分系数(PI)的整定问题。以TMS320F2812芯片为控制器设计了光伏逆变系统的软件部分,给出了系统软件算法的流程。利用MATLAB对空间矢量的调制算法、软件锁相算法和并网运行控制策略进行了仿真,总结了PI调节器的整定规律。仿真结果表明了并网控制策略的正确性:由太阳能电池板发出的能量能够以较高的功率因素反馈至电网。更多还原

【Abstract】 The solar energy, because of cleanliness, high efficiency and continuable development, attracts more and more attention by many countries. Grid-connected photovoltaic (PV) system is the trend of photovoltaic system’s development.This thesis mainly researches the PV grid-connected inverter, which is the most important device in Grid-connected PV system. It’s function includes two sides: the first is that it makes the inverter work in Maximum power point state, the second is that it converts the DC generated by PV to AC ,it also makes it sure that the current which is the output of the Inverter is synchronous with grid voltage. The thesis firstly introduces the circuit structure of three-level inverter, compares two modulation arithmetic of the inverter, mainly analyses the principle and realization steps of Space Vector Pulse Width Modulation (SVPWM). Next, the thesis introduces the method of three-phase grid’s Phase Lock based on instantaneous reactive power。Traditional PLL is not satisfactory in the unbalanced AC power system condition, For this reason, the thesis gives the improved method. Then, the thesis establishes the mathematical mode of Grid-connected PV system in three kinds of coordinate system, the voltage and current pairs of two closed-loops vector control strategy is importantly studied,uses the methods of typical control system designation and experimentation to solve the factors of PI controller.The thesis gives the inverter’s soft system designation based on the DSP chip of TMS320F2812, also gives the flow chart of soft arithmetic. The simulation of SVPWM, SPLL,PV grid-connected control strategy is researched by MATLAB, and the rule of PI controller is also summarized. The result shows the exactness of PV grid-connected control strategy, the energy generated by PV can be feed back to AC power system with high power-factor.更多还原