Estimation of Open Circuit Voltage and electrical parameters of a battery based on signal processed by Recursive Least Square method using two separate forgetting factors

摘要

Many research topics related to a battery such as fault detection and estimation have been shown for more than a decade since a battery has became one of the most important components of electrical vehicles (EVs). In this paper, estimation of open circuit voltage and electrical parameters of a battery was investigated. Two separate forgetting factors of Recursive Least Square (RLS) were used to process the data signal. One of it was used to estimate Open Circuit Voltage (OCV), while the other was used to estimate electrical parameters of the battery. The result is that OCV can be estimated with MSE 1.97×10-5. On the other hand, electrical parameters have also been successfully estimated. Since it is difficult to measure the real value of electrical parameters, the accuracy of the electrical parameters estimation is determined by MSE of terminal voltage estimation after the estimated electrical parameters' value are inserted into the circuit model. The MSE of terminal voltage estimation caused by electrical parameters estimation is 5.3×10-5.