单相离网型逆变器的设计大学生.doc

摘 要 节能和环保已成为当今世界的两大主题。利用风能、太阳能发电是对两种最为理想、无污染的绿色再生资源的利用，目前已成为开发研究的重要方向。风-光互补发电系统是一种将太阳能和风能转化为电能的发电系统。逆变器是风光互补发电系统的关键设备，直接关系到供电质量和系统运行的可靠性。这样，采用什么样的方法能使逆变器发出稳定的交流电给负载供电，是要解决的首要问题。本文以理论分析为基础，通过对逆变器的控制策略的分析，设计单相离网型全桥逆变器，通过具体实验验证了设计的正确性。 首先，分析全桥逆变器的控制策略。通过对SPWM单极性和双极性两种控制方式和工作过程的分析，分别对其采样方式和输出电压谐波进行了分析计算，论证了其谐波抑制特性，最终确定采用单极性全桥SPWM控制方式。 其次，根据设计要求和控制方式，给出了单相离网型逆变器的的主电路结构。对逆变器的主功率部分进行了具体设计，设计了电路的驱动保护，通过建立了滤波器的数学模型，具体设计了低通LC滤波器，还设计了系统过流保护，过压欠压保护和过温保护。使用模拟控制的方法，设计了逆变器的控制电路，驱动电路，实现了对逆变器主功率电路的控制，并且给出了各部分的实测波形和实验结果。 最后，分别计算了电感损耗中的磁芯损耗和电感线圈损耗。功率开关器件损耗中考虑反并联二极管的影响,计算了IGBT的通态损耗，开通损耗和关断损耗。 关键词：SPWM；单极性；单相；逆变器 Abstract Energy-economizing and environmental protection have become the two major subject, nowadays. Wind and solar energy are best green non-polluting renewable resources, and related research has developed a major issue. Wind-optical hybrid generating system is a generating system that a solar and wind energy will be converted to electrical energy. Inverter is the key to wind-optical hybrid generating system, directly related to the reliability of the power quality and system operation. Then, it is the primary problem that what kind of approach will enable the inverter to the load of the AC power supply steadily. Based on a theoretical analysis and the analysis of the inverter control strategy, we design single-phase off-grid full-bridge inverter and verify the correctness of the design through specific experiments.  First of all, it is analyzed that full-bridge inverter control strategy. By the analysis of control methods and work processes of unipolar and bipolar SPWM, we analyze and calculate, respectively, their sampling methods and the output voltage harmonic waves, demonstrate that the characteristics of the harmonic suppression, and ultimately determine the use of unipolar full-bridge SPWM control. Secondly, in accordance with design requirements and control methods, it was given off-grid single-phase inverter main circuit. It was designed concretely the main