摘要
针对单周控制开关功率放大器存在的输出直流偏置问题,从理论上进行了分析,结果表明输出直流偏置电压的大小与复位脉冲宽度成正比。为了消除输出直流偏置电压,提出了电压补偿的解决方案,给出了补偿电压的计算公式。对补偿前和补偿后的系统进行了仿真和实验研究。仿真和实验结果表明,电压补偿方法能有效消除输出直流偏置问题,改善放大器的THD,验证了理论分析的正确性。
This paper analyzes the output DC offset in a switching amplifier with one cycle control in theory firstly. The analysis results show that output DC offset voltage is proportional to width of reset pulse. Then according to the result, a novel voltage compensation technique is proposed to improve this DC offset voltage. The design formula for computing compensation voltage is given Furthermore, the relationship between gain and circuit parameters of the proposed switching amplifier are analyzed. The amplifiers with and without compensation are researched by simulation and experiment. The results show that the proposed compensation technique solve the output DC offset and improve total harmonic distortion effectively, which is consistent with the results of theory analysis.
出处
《电工技术学报》
EI
CSCD
北大核心
2004年第5期106-110,共5页
Transactions of China Electrotechnical Society
