基于相移PWM调制的多电平D类功率放大器谐波分析  

Analysis of a Cascade Multilevel Class-D Power Amplifier Output Harmonic

作　　者：张缨[1] 李耀华[2] 蔡凌[1] 孟庆德[1] 

机构地区：[1]海军装备研究院,北京100073 [2]中国科学院电工研究所,北京100080

出　　处：《电工技术学报》2007年第7期103-108,共6页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金资助项目(50407006)

摘　　要：介绍了一种新颖的基于级联型多电平拓扑结构的开关型功率放大器,采用单极倍频相移PWM技术,其开关频率为单个单元开关频率的2N倍,总的输出电压波纹小。分析了级联型多电平技术的特点,重点研究了采用单极倍频相移PWM技术的多电平输出信号的谐波,最后研制了一台级联型多电平的D类功率放大器。研究结果证明了所研究的级联型多电平D类功率放大器输出电压谐波的正确性,表明该放大器具有良好的跟踪性和稳定性。A novel switch-mode power amplifier based on a cascade multicell multilevel circuit topology is introduced in the paper. By application of the concept of multicell topology operated in a unipolar phase-shifted PWM control to switch-mode amplifier system. The effective switching of output results in 2N times the switching frequency of each full-bridge. Due to the phase-shifted PWM control of the individual switching cells, the output voltage ripple of the total system is considerably small. The advanced characteristic of cascade multilevel technique are analyzed. The main subject of this paper is study of the output harmonic of class-D amplifier. Then a cascade multilevel class-D power amplifier is built in the laboratory. The results of measurements taken from a laboratory setup are presented, which prove the research about the output signal＇s harmonic is right. The proposed amplifier obvious increases the bandwidth. The system shows an excellent response and stability.

关 键 词：D类功率放大器 多电平控制 相移PWM控制 

分 类 号：TM464[电气工程—电器]