Second-Order Discrete-Time Sliding Mode Observer for State of Charge Determination Based on a Dynamic Resistance Li-Ion Battery Model

Energies

Daehyun Kim¹  Keunhwi Koo¹  Jae Jin Jeong¹  Taedong Goh¹ 

[1] Department of Electrical Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang 790-784, Korea; E-Mails:

关键词: Li-ion battery;    second-order discrete sliding mode observer;    dynamic resistance;    state of charge;   

DOI  :  10.3390/en6105538

来源: mdpi

【 摘 要 】

A second-order discrete-time sliding mode observer (DSMO)-based method is proposed to estimate the state of charge (SOC) of a Li-ion battery. Unlike the first-order sliding mode approach, the proposed method eliminates the chattering phenomenon in SOC estimation. Further, a battery model with a dynamic resistance is also proposed to improve the accuracy of the battery model. Similar to actual battery behavior, the resistance parameters in this model are changed by both the magnitude of the discharge current and the SOC level. Validation of the dynamic resistance model is performed through pulse current discharge tests at two different SOC levels. Our experimental results show that the proposed estimation method not only enhances the estimation accuracy but also eliminates the chattering phenomenon. The SOC estimation performance of the second-order DSMO is compared with that of the first-order DSMO.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.