基于PWM技术2kWACDC的设计与研究.doc

摘 要 传统的二极管整流器以及由半可控的晶闸管组成的相控整流器，由于其整流环节不可控，导致网侧功率因数低，电流谐波大，能量不可逆等缺点，PWM 整流器具有输入电流正弦且实现单位功率因数、直流电压恒定且可以迅速调节控制，以及良好的动态性能且可以实现能量的双向流动等显著优点，因而得到了广泛的应用与研究。 本文首先分析了三相电压型PWM整流器的工作原理，并分析给出了其主电路开关函数的数学模型和坐标转换的dq数学模型。然后通过分析三相电压型PWM的控制方法，介绍了双闭环控制的基本原理，并分别对电压外环控制、电流内环控制等各子系统进行了详细的分析论述, 计算了交流侧电感和直流侧电容的基本参数，推导出PWM整流器双闭环控制系统的传递函数框图,最后在matlab/simulink搭建仿真模型，仿真结果验证了控制策略的可行性。 关键词：PWM整流器；双闭环控制策略；仿真分析 Abstract Traditional un-controlled diode rectifier and phase controlled rectifier consisted of half-controlled thyristor，have some drawbacks: low ac-side power factor, big current ripple and un-revisable power flow, PWM rectifier has significant advantages of sinusoidal input current and unit power factor, DC voltage constant and rapid adjustment control, good dynamic performance and bi-direction power flow and so on, thus gains extensive application and research. Firstly, the paper analyzes the working principle of three-phase voltage-source PWM rectifier, and analyzes its main circuit mathematical model which based on switch function and the mathematical models of dq coordinate transformation. Then we introduce the basic principles of double closed loop control by analyzing the three-phase voltage-source PWM control method, and outer loop control voltage, respectively, inner current loop control and other subsystems were analyzed and discussed in detail. The basic parameters of AC side inductance and DC side capacitance is calculated and the PWM rectifier dual closed loop control system transfer function block diagram is derived. Finally, in matlab/simulink environment, a simulation model is built. Simulation result shows that the validity of the control strategy. Keywords: PWM Rectifier; Dual-close-loop control strategy; Simulation analysis 2 内蒙古工业大学本科毕业设计说明书 1