基于铝电解电容器放电规律的ESR和电容监测方法

铝电解电容器是电力电子系统中的核心组件,也是最容易失效的电力电子元器件之一,其运行状态直接影响电力电子系统的稳定性。为了及时发现并更换存在问题的铝电解电容器,提出了一种基于铝电解电容器放电规律的等效串联电阻(ESR)和电容的监测方法。通过对铝电解电容器放电过程中的电压曲线实时采样,并结合其放电过程中电压和电流之间的关系式,建立ESR和电容的计算模型。最后,设计一套可以监测铝电解电容器ESR值和电容值变化的系统,并进行实验验证。实验结果表明,该方法可以准确测量铝电解电容器的ESR值和电容值,从而验证了所提方法的可行性。

Method for monitoring ESR and capacitance based on discharge rule of aluminum electrolytic capacitors

Aluminum electrolytic capacitor is the core component of power electronic system, and it is also one of the most easily failed power electronic components. Its operation status directly affects the stability of power electronic system. In order to find and replace the problematic aluminum electrolytic capacitor in time, a monitoring method of ESR(Equivalent Series Resistance) and capacitance based on the discharge rule of aluminum electrolytic capacitors is proposed. The calculation model of ESR and capacitance is estab-lished by sampling the voltage curve in the discharge process of aluminum electrolytic capacitors in real time and combining the relationship between voltage and current in the discharge process. Finally, a system is designed to monitor the changes of the ESR and capacitance values of aluminum electrolytic capacitor, and experimental verification is conducted. Experimental results show that this method can accurately measure the ESR and capacitance values of aluminum electrolytic capacitors, thus verifying the feasibility of the proposed method.