CAJ | 학술논문

电解电容是电源系统中最易失效的元件，其性能参数的退化直接影响系统的可靠性，因此在线监测其等效串联电阻(equivalent series resistance，ESR)和电容值(capacitance， C)的变化十分关键。该文提出了一种新的非侵入式在线监测连续导通模式(continuous conduction mode，CCM) Buck变换器输出电容ESR和C的方法。通过分析输出电压交流分量，结合连续模式下的电容电流表达式，建立ESR和C的实时在线计算模型，设计了电解电容在线监测系统。该方案无需电流传感器，仅采样脉冲宽度调制(pulse-width modulation，PWM)信号和输出电压，不改变Buck变换器的电气结构，就可监测不同工作状态下的ESR和C，完成一台监测系统原理样机并进行实验，实验结果验证了所提方法的有效性。
전해전용시전원계통중최역실효적원건，기성능삼수적퇴화직접영향계통적가고성，인차재선감측기등효천련전조(equivalent series resistance，ESR)화전용치(capacitance， C)적변화십분관건。해문제출료일충신적비침입식재선감측련속도통모식(continuous conduction mode，CCM) Buck변환기수출전용ESR화C적방법。통과분석수출전압교류분량，결합련속모식하적전용전류표체식，건립ESR화C적실시재선계산모형，설계료전해전용재선감측계통。해방안무수전류전감기，부채양맥충관도조제(pulse-width modulation，PWM)신호화수출전압，불개변Buck변환기적전기결구，취가감측불동공작상태하적ESR화C，완성일태감측계통원리양궤병진행실험，실험결과험증료소제방법적유효성。
As the electrolytic capacitor is apt to fail in power circuits and its degradation directly affects the reliability of the entire system, it is very important to monitor its electrical parameters, mainly the equivalent series resistance (ESR) and the capacitance (C). A novel online monitoring method of capacitor’s ESR and C for continuous conduction mode (CCM) Buck converters is proposed in this paper. Based on the ac component of capacitor voltages and the constitution of capacitor currents in CCM, the calculation model is founded, then the online monitoring system of electrolytic capacitors is built. The method needs no current sensors and is effective for the CCM Buck converter operating in different conditions without changing the electrical structure. Implementation of the monitoring system is presented. The experimental results validate the effectiveness of the method.