Energy awareness for supercapacitors using Kalman filter state-of-charge tracking

JOURNAL OF POWER SOURCES

卷:296

Article

Nadeau, Andrew¹  Hassanalieragh, Moeen¹  Sharma, Gaurav¹  Soyata, Tolga¹ 

[1] Univ Rochester, Dept Elect & Comp Engn, Rochester, NY 14627 USA

关键词: Supercapacitor;    Three branch model;    State of charge;    Parameter estimation;    Kalman;    Energy awareness;   

DOI  :  10.1016/j.jpowsour.2015.07.050

来源: Elsevier

【 摘 要 】

Among energy buffering alternatives, supercapacitors can provide unmatched efficiency and durability. Additionally, the direct relation between a supercapacitor's terminal voltage and stored energy can improve energy awareness. However, a simple capacitive approximation cannot adequately represent the stored energy in a supercapacitor. It is shown that the three branch equivalent circuit model provides more accurate energy awareness. This equivalent circuit uses three capacitances and associated resistances to represent the supercapacitor's internal SOC (state-of-charge). However, the SOC cannot be determined from one observation of the terminal voltage, and must be tracked over time using inexact measurements. We present; 1) a Kalman filtering solution for tracking the SOC; 2) an on-line system identification procedure to efficiently estimate the equivalent circuit's parameters; and 3) experimental validation of both parameter estimation and SOC tracking for 5 F, 10 F, 50 F, and 350 F supercapacitors. Validation is done within the operating range of a solar powered application and the associated power variability due to energy harvesting. The proposed techniques are benchmarked against the simple capacitive model and prior parameter estimation techniques, and provide a 67% reduction in root-meansquare error for predicting usable buffered energy. (C) 2015 Elsevier B.V. All rights reserved.

【 授权许可】

Free