Control method of three-level neutral-point-clamped inverter based on voltage vector diagram partition

A new modulation approach was presented for the control of neutral-point (NP) voltage variation in the three-level NP-clamped voltage source inverter, and the average NP current model was established based on vector diagram partition. Thus, theory base was built for balancing control of NP potential. Theoretical analysis and experimental results indicate that the proposed method for NP balancing control vector synthesizing concept based can make the average NP current zero, and do not influence NP potential within every sample period. The effectiveness of proposed research approach was verified by simulative and experimental results.     

一种变压器耦合串联型三相二重化电压源逆变器的谐波特性分析

多重化电力变换器具有良好的输出特性,其有效开关频率高、波形质量好、动态响应快、冗余度高,在大容量电力变换器中占有优势.文章深入分析了一种变压器耦合串联型三相二重化电压源逆变器及其谐波特性,阐述了其物理意义,揭示了多重化后逆变器输出谐波的相位关系和对消规律.物理意义明确,易于理解.分析方法具有普遍性,可以应用于任意重化逆变器的谐波分析.     

具有滤波与能量回馈双功能的电力变换器研究

研究一种具有滤波与能量回馈双功能的电梯能量回馈器,当电梯处于能量再生状态运行时,回馈器将能量回馈到电网;当电梯处于非能量再生状态运行时,即回馈器处于闲置状态时,为了提高设备利用率,使回馈器运行在有源电力滤波状态。以并联型有源电力滤波器为研究对象,对其拓扑结构、补偿分量的检测算法、控制策略等问题作了较系统研究。实验结果表明,该回馈器工作稳定可靠,具有良好的动、静态性能。并在MATLAB环境下进行了相应仿真,仿真结果表明,该滤波器（回馈器）能够准确地补偿谐波电流和无功功率,动态响应速度也很快。