中文摘要：

为准确估计含三相不控整流的交–直–交变换器所产生的谐波,提出了可深入分析其谐波产生特性的新型模型。首先提出简化变换器谐波分析的三相电压源型整流（voltage source converter,VSC）等值电路,并对电路参数进行了估算。通过分析三相VSC在电容充、放电各阶段的工作原理,在频域中求解出了供电电压与其所产生的谐波电流的解析关系。建立了每个周期电容充放电的数学模型,基于此计算出三相VSC中二极管的导通和关断时刻,并估算出直流侧电压。进而将交–直–交变换器时域的谐波非线性特征转化为频域的谐波耦合导纳矩阵模型,矩阵中的元素可直观地体现出各次谐波电压和谐波电流之间的耦合关系。通过将所提出模型的编程计算结果与Simulink时域仿真结果、实验测量结果以及传统恒流源模型的计算结果进行对比,验证了谐波耦合矩阵模型可准确地表征含三相不控整流的交–直–交变换器所产生的谐波。

英文摘要：

In order to estimate the harmonic currents generated by the uncontrolled rectified AC/DC/AC converter more accurately, a new harmonic model to study its harmonic generation characteristics was proposed. First an equivalent voltage source converter circuit was proposed to simplify the harmonic analysis of the AC/DC/AC converter. Estimation formula was derived for the circuit equivalent parameters. By analyzing the principle of the circuit capacitor＇s charging mode and discharging mode, the relationship among the supply voltages and its generated harmonic currents was explored in the frequency domain with an analytical form. Based on the mathematical model, the diode＇s conduction angle and extinction angle were calculated and the DC voltage was estimated. This model transfers the AC/DC/AC converter nonlinear characteristics in the time-domain to a harmonically coupled admittance matrix model in the frequency-domain. Moreover, the matrix elements can explicitly reflect the coupled relationship between the harmonic voltages and the generated harmonic currents. The model＇s validity and accuracy have been verified by comparing the results from its calculation, the time domain simulation, lab experiment and the traditional constant current source model＇s calculation.