开关电源中高带宽线性调整支路的应用

Application of high-bandwidth linear adjustment branch in switching power supply

在中国散裂中子源中,快循环同步加速器射频系统要求偏流源电源的输出带宽大于10 kHz,而开关电源样机的输出带宽最大输出只有3 kHz,无法满足带宽设计要求。因此在偏流源开关电源正式工程机中,加入了线性调整支路,以提高整个系统的输出带宽。开关电源中加入线性调整支路的方法有多种,本文介绍了开关电源并联线性调整支路方法的选取原则,分析了不同方法的优缺点,并对加入线性调整支路前后开关电源的带宽测试结果进行了对比。测试结果表明,线性调整支路可以弥补开关电源带宽的不足,加并联线性支路后的开关电源输出带宽大于10 kHz。

Background： China Spallation Neutron Source （CSNS） is a medium-sized high-flux spallation neutron source under construction with Rapid Cycling Synchrotron （RCS） of 25 Hz as the main accelerator. The RF cavity of RCS requires that the output bandwidth of bias current source is greater than 10 kHz, while the maximum output bandwidth of switching power supply prototype is only 3 kHz, which can＇t meet the design requirements. Purpose： In order to improve the output bandwidth of the entire system, the linear adjustment branch is added to the switching power supply in a formal bias current source. Methods： This paper introduced the principle of selecting the linear adjustment branch, analyzed the advantages and disadvantages of the different methods and showed the test results of output bandwidth after adding linear adjustment branch. Results： The output bandwidth of the system after adding linear adjustment branch is greater than 10 kHz. Conclusion： Linear adjustment branch can compensate for the output bandwidth of the switching power supply.