基于DDS技术的蓄电池内阻测量方法的研究

Method of Testing Battery Internal Resistance Based on DDS

针对交流法测量蓄电池内阻受诸多因素的影响,准确度难以提高的问题,提出了基于直接数字合成技术和锁相放大器相结合测量内阻的新方法。详细阐述了用相位累加器精确地获取锁相放大器同步信号的工作原理、用相位累加移相技术精确测量电池内阻两端电压和电流相位差的方法,设计了采用锁相放大器实现蓄电池内阻测量的电路。实验结果表明:该方法具有可靠性高,测量数据准确等优点。

It is difficult to improve the accuracy of testing internal resistance with AC inserting because of effect from many factors. A novel method of testing internal resistance based on lock-in amplifier and DDS was put forward. The principle of acquiring synchronous signal of lock-in amplifier with DDS technology, and the method of measuring phase accurately between voltage across battery internal resistance and current passing it using technology of moving phase by phase accumulator was introduced. The circuit to achieve testing battery internal resistance with lock-in amplifier was designed. It is proved by experiment that the new method has high reliability and accuracy.