相敏检波器（PSD）在电池内阻测试中的运用

Application of Phase Sensitive Detector (PSD) in Battery Internal Resistance Test

电池内阻的测试,主要是利用一组交流信号通过待测电池,提取出电池两端的交流信号幅值,利用电子开关鉴相器对测试信号进行矢量分离,最终得出所测的电阻值。很多场合对于电池内阻的测试有较高的精度要求。不同的电池,其内部的阻值也不一样,有几mΩ至十几kΩ的跨度,所以在这个范围内,均要实现电池内阻的有效测试。利用PSD技术高信噪比的测试特点,能很好地实现微弱信号的检测,因而能很好地实现电池内阻的测试。

The test of battery internal resistance is mainly to use a group of ac signals through the battery to be tested,take out the AC signal amplitude at both ends of the battery,use electronic switch phase detector to conduct vector separation of the test signal,and finally get the measured resistance value. In many cases,high accuracy is required for the measurement of battery internal resistance. Different battery,its internal resistance is also different,spans ranging from several mΩ to more than ten kΩ,so in this range,to achieve the effective test battery internal resistance. Using PSD technology,its high signal-to-noise ratio test characteristics,can well achieve weak signal detection,so it can well achieve the battery resistance test.