Challenges of Monitoring High-voltage Battery Packs in Hybrid and Electric Vehicles W.Guo, C.DominguesJune 2011 GSA Forum
June 20, 2011
Worldwide concerns of climate change and oil supply have triggered great interest in the electric vehicle (EV) and hybrid EV (HEV) segment of the automotive market. This rapid growth segment is also stimulated by the development of rechargeable batteries. As these “green” vehicles are powered by high-voltage (HV) battery packs consisting of hundreds of series-connected cells, the complexity of such packs has dramatically grown. Thus, the safety, reliability and efficiency of these packs are inherently dependent upon a sophisticated battery management system (BMS).
A primary task of the BMS is to monitor the battery state- of-charge (SOC) by collecting run-time information of pack current, cell voltage and temperature. This creates challenges for intellectual property (IP)-focused fabless companies to provide high- performance, cost-effective and flexible analog front ends (AFEs) to be integrated into competitive battery monitoring-specific ICs to meet various automotive market needs.
This article presents a brief overview of the underlying issues of such monitoring ICs, explains the two dedicated data acquisition AFEs required for individual cell characteristic monitoring and pack current measurement, and introduces the need for application-level simulation to guarantee AFE performance at the system level...