基于H桥级联的电压暂降补偿研究.doc

摘要 关键词： Abstract With modern technology and national economic development, power quality problems by the electricity sector and the users attention. Among them, system failures caused by the voltage sag, leading to sensitive device is not working the main reason, causing serious economic losses. Voltage dips and short interruption is a growing concern in recent years, the dynamic power quality problem is that users complain about the electricity sector and the cause of most complaints. Voltage dips and short interruption can cause users to sensitive equipment or automatic production line does not work even work interruption caused considerable economic losses. For the high-tech modern industrial and commercial financial system load, resulting in economic losses is particularly prominent. This paper presents a dynamic voltage restorer (DVR) device, with the minimum voltage method to compensate for voltage sag. The device topology, device selection is analyzed and calculated, and PSCAD / EMTDC simulation software to do the simulation, a cascade using multi-level H bridge topology control scheme can effectively suppress high-precision system a variety of voltage sags, the voltage fluctuation amplitude reaches the standard +5% -5% to ensure normal operation of equipment. Simulation and experimental results show that the device can effectively simulate a variety of current disturbances occur. The simulation can be developed 400V/100kVA prototype for the future lay a theoretical foundation Key words：Harmonic Dynamic Voltage Restorer pwm H bridge 目 录 摘 要 I 绪论 3 1.1 课题背景 3 1.2 电压暂降的产生及治理 5 1.3 电压暂降补偿的发展 8 1.4 短路电流限制 12 1.5 小结 13 2 控制策略 14 2.1 现有电压暂降的检测方法 14 2.2 瞬时无功功率理论 16 2.3 对补偿策略的研究 18 2.4 最小能量法 19 2.5 最小电压法 20 2.6 控制原理图 21 2.7 PQ变换法 22 2.8 PI调节法 23 2.9 PWM控制技术 24 2.10 小结 25 3参数设计 26 3.1 主电路拓扑 26 3.2 系统电抗及负荷参数设计 27 3.3 IGBT 28 3.4 PWM整流IGBT参数设计 30 3.5 级联H桥IGBT参数设计 31 3.6 限流电抗参数设计 31 3.7 LC低通滤波器的参数设计 32 3.9 本章总结 35 4电压暂降补偿软件仿真 36 4.1 仿真软件的选用 36 4.2 主电路拓扑 36 4.3 仿真