【摘要】：由于三相電壓型PWM整流器具有輸入單位功率因數(shù)、高質(zhì)量的直流電壓和低失真輸入電流等優(yōu)越的性能，，其應(yīng)用日益廣泛。而在三相電壓型PWM整流器的實際運行中，會出現(xiàn)電壓突然崩潰、控制系統(tǒng)間歇振蕩、不明電磁噪聲等非正常工作現(xiàn)象，因此，從三相電壓型PWM整流器屬于非線性系統(tǒng)這一本質(zhì)出發(fā)，利用非線性動力學研究三相電壓型PWM整流器的不規(guī)則現(xiàn)象，有助于深入了解三相電壓型PWM整流器的運行規(guī)律，對三相電壓型PWM整流器的推廣應(yīng)用具有實際意義。 為了闡述三相電壓型PWM整流器發(fā)生直流側(cè)電壓崩潰現(xiàn)象的機理，本文基于電壓與電流的雙閉環(huán)控制策略建立了三相電壓型PWM整流器的閉環(huán)模型，然后針對不同類型的負載，運用非線性動力學理論分析了負載參數(shù)大小對電壓崩潰現(xiàn)象的影響，最后進行了仿真和實驗驗證。 本文做的主要工作包括以下幾個方面： 1.對采用電壓外環(huán)和電流內(nèi)環(huán)雙環(huán)控制的三相電壓型PWM整流器建立了閉環(huán)模型，然后分別從系統(tǒng)能量守恒和PWM過調(diào)制兩個不同角度分析了三相電壓型PWM整流器發(fā)生直流側(cè)電壓崩潰現(xiàn)象的機理。 2.對帶純電阻負載的三相電壓型PWM整流器，利用雅克比矩陣法推導雅克比矩陣特征根與負載電阻R和直流側(cè)濾波電容C之間的關(guān)系，得到直流側(cè)電壓崩潰時R和C的臨界值。 3.對帶阻感負載的三相電壓型PWM整流器建立閉環(huán)模型，通過計算不同負載電阻R對應(yīng)的雅克比矩陣特征根，得到帶阻感負載的三相電壓型PWM整流器的穩(wěn)定工作區(qū)域；進而基于所建立的閉環(huán)模型，畫出負載電阻R突變時各個狀態(tài)變量的變化軌跡圖，得到直流側(cè)電壓崩潰時的臨界電阻值。 4.與帶阻感負載的三相電壓型PWM整流器的分析類似，對帶反電動勢負載的三相電壓型PWM整流器進行分析，得到直流側(cè)電壓崩潰時的臨界電阻值和臨界反電動勢值。 5.上述分析結(jié)果均用Matlab/Simulink進行了仿真驗證，此外還基于RT-LAB半實物仿真平臺搭建三相電壓型PWM整流器的實驗電路，進行相關(guān)的實驗，驗證電壓崩潰現(xiàn)象。
[Abstract]:The three-phase voltage-source PWM rectifier is widely used because of its excellent performance such as input unit power factor, high quality DC voltage and low distortion input current. But in the actual operation of three-phase voltage-source PWM rectifier, there will be sudden voltage collapse, intermittent oscillation of control system, unknown electromagnetic noise and other abnormal working phenomena. Starting from the fact that three-phase voltage-source PWM rectifier belongs to nonlinear system, the irregular phenomenon of three-phase voltage-source PWM rectifier is studied by nonlinear dynamics, which is helpful to understand the running rule of three-phase voltage-source PWM rectifier. It is of practical significance for the popularization and application of three-phase voltage source PWM rectifier. In order to explain the mechanism of DC side voltage collapse in three-phase voltage-source PWM rectifier, the closed-loop model of three-phase voltage-source PWM rectifier is established based on the double-closed-loop control strategy of voltage and current. The influence of load parameters on voltage collapse is analyzed by using nonlinear dynamics theory. Finally, the simulation and experimental results are carried out. The main work of this paper includes the following aspects: 1. The closed-loop model of three-phase voltage-source PWM rectifier controlled by voltage outer loop and current inner loop is established. Then the mechanism of DC side voltage collapse of three-phase voltage-source PWM rectifier is analyzed from two different angles of energy conservation and PWM overmodulation. 2. For a three-phase voltage-source PWM rectifier with pure resistor load, the relationship between the characteristic root of Jacobian matrix and the load resistance R and the DC side filter capacitance C is derived by using the Jacobian matrix method, and the critical values of R and C when the DC side voltage collapses are obtained. 3. The closed-loop model of three-phase voltage-source PWM rectifier with resistive load is established. The stable working area of three-phase voltage-source PWM rectifier with resistive load is obtained by calculating the characteristic roots of Jacobis matrix corresponding to different load resistors. Then, based on the closed-loop model established, the trajectory diagram of each state variable when the load resistance R changes is drawn, and the critical resistance value when the DC side voltage collapses is obtained. 4. Similar to the analysis of three-phase voltage-source PWM rectifier with resistive load, the three-phase voltage-source PWM rectifier with backEMF load is analyzed, and the critical resistance and critical back-EMF value of DC side voltage collapse are obtained. 5. In addition, the experimental circuit of three-phase voltage-source PWM rectifier is built based on RT-LAB hardware-in-the-loop simulation platform, and the related experiments are carried out to verify the phenomenon of voltage collapse.
【學位授予單位】：華南理工大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：TM46

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相關(guān)期刊論文 前1條

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