赛能蓄电池SN-12V120CH详细/型号
赛能蓄电池作为电源系统停电时的备用电源，已广泛的应用于工业生产、交通、通信等行业。如果电池失效或容量不足，就有可能造成重大事故，所以必须对蓄电池的运行参数进行全面的在线监测。蓄电池状态的重要标志之一就是它的内阻。无论是蓄电池即将失效、容量不足或是充放电不当，都能从它的内阻变化中体现出来。因此可以通过测量蓄电池内阻，对其工作状态进行评估。目前测量蓄电池内阻的常见方法有：//www.sinonteamdc.com
Battery as a backup power source when power system is outage, has been widely used in industrial production, transportation, communications and other industries. If the battery fails or the capacity is insufficient, it is possible to cause major accidents. Therefore, the on-line monitoring of the operation parameters of the battery must be carried out. One of the important signs of the battery state is its internal resistance. Whether the battery is going to fail, the capacity is insufficient or the charge and discharge is not proper, it can be reflected from its internal resistance changes. Therefore, the working state of the battery can be evaluated by measuring the internal resistance of the battery. The common methods for measuring the internal resistance of the battery are:
赛能蓄电池SN-12V120CH详细/型号
密度法
(1) density method
密度法主要通过测量蓄电池电解液的密度来估算蓄电池的内阻，常用于开口式铅酸电池的内阻测量，不适合密封铅酸蓄电池的内阻测量。该方法的适用范围窄。
Density method is used to estimate the internal resistance of the battery by measuring the density of the battery electrolyte, which is often used to measure the internal resistance of the open lead-acid battery, which is not suitable for the internal resistance measurement of the sealed lead-acid battery. The application of this method is narrow.
赛能蓄电池SN-12V120CH详细/型号
开路电压法
(2) open circuit voltage method
开路电压法是通过测量蓄电池的端电压来估计蓄电池内阻，精度很差，甚至得出错误结论。因为即使一个容量已经变得很小的蓄电池，再浮充状态下其端电压仍可能表现得很正常。
The open circuit voltage method is used to estimate the internal resistance of the battery by measuring the terminal voltage of the battery. The accuracy is very poor, and even the wrong conclusion is obtained. Because even if a battery capacity has become very small, then the floating state of terminal voltage is still likely to be normal.
赛能蓄电池SN-12V120CH详细/型号
直流放电法
(3) direct current discharge method
直流放电法就是通过对电池进行瞬间大电流放电，测量电池上的瞬间电压降，通过欧姆定律计算出电池内阻。虽然这种方法在实践中也得到了广泛的应用，但是它也存在一些缺点。如用该方法对蓄电池内阻进行检测必须是在静态或是脱机状态下进行，无法实现在线测量。而且大电流放电会对蓄电池造成较大的损害，从而影响蓄电池的容量及寿命。
The DC discharge method is to measure the instantaneous voltage drop on the battery by discharging the battery instantaneously, and calculate the internal resistance of the battery by Ohm's law. Although this method has been widely applied in practice, it also has some shortcomings. If we use this method to detect the internal resistance of battery, it must be carried out under static or offline state, and online measurement can not be achieved. Moreover, the large current discharge will cause great damage to the battery, which will affect the capacity and life of the battery.
交流注入法
(4) AC injection method
交流法通过对蓄电池注入一个恒定的交流电流信号IS，测量出蓄电池两端的电压响应信号Vo，以及两者的相位差
In the AC method, a constant current signal IS is injected into the battery, and the voltage response signal Vo at both ends of the battery is measured, and the phase difference between them is measured.
设正弦信号为：
The sine signal is set as:
精确测量蓄电池内阻方法的研究
Study on the method of accurately measuring the internal resistance of the battery
（1）
(1)
蓄电池两端的响应电压信号为：
The response voltage signals at both ends of the battery are:
（2）
(2)
精确测量蓄电池内阻方法的研究
Study on the method of accurately measuring the internal resistance of the battery
为注入蓄电池的交流电流和其两端响应电压信号的相位差。
The phase difference between the AC current and the voltage signals at both ends of the battery is injected.
通过模拟乘法器后有：
After the analog multiplier, there are:
精确测量蓄电池内阻方法的研究
Study on the method of accurately measuring the internal resistance of the battery
K为模拟乘法器的放大系数。
K is the magnification factor of the analog multiplier.
进行低通滤波后滤掉交流成分得：
After low pass filtering, filter off the AC component:
精确测量蓄电池内阻方法的研究
Study on the method of accurately measuring the internal resistance of the battery
（3）
(3)
由交流法测内阻原理得：
The principle of measuring internal resistance by AC method is obtained.
精确测量蓄电池内阻方法的研究
Study on the method of accurately measuring the internal resistance of the battery
（5）
(5)
式中I为交流恒流源信号的最大值。比较（4）、（5）可得：
I is the maximum value of the AC constant current source signal. Comparison (4) and (5) can be obtained:
精确测量蓄电池内阻方法的研究
Study on the method of accurately measuring the internal resistance of the battery
上式中K、A、I都是已知量，而u为经过A/D采样送到单片机进行处理的采样值，所以在单片机中进行一个简单的除法运算便能得到蓄电池内阻了。
The K, A and I in the upper form are all known, while u is sampled by the A/D sample to the single chip processor, so a simple division operation in the single chip can get the internal resistance of the battery.