Performance Analysis of Commercial Passive Balancing Battery Management System Operation Using a Hardware-in-the-Loop Testbed

Abstract

With increased usage, individual batteries within the battery pack will begin to show disparate voltage and State of Charge (SOC) profiles, which will impact the time at which batteries become balanced. Commercial battery management systems (BMSs), used in electric vehicles (EVs) and microgrids, typically send out signals suggesting removal of individual batteries or entire packs to prevent thermal runaway scenarios. To reuse these batteries, this paper presents an analysis of an off-the-shelf Orion BMS with a constrained cycling approach to assess the voltage and SOC balancing and thermal performances of such near-to-second life batteries. A scaled-down pack of series-connected batteries in 6s1p and 6s2p topologies are cycled through a combination of US06 drive and constant charge (CC) profiles using an OPAL-RT real-time Hardware-in-the-loop (HIL) simulator. These results are compared with those obtained from the Matlab/Simulink model to present the error incurred in the simulation environment. Results suggest that the close-to-second life batteries can be reused if operated in a constrained manner and that a scaled-up battery pack topology reduces incurred error.

A Joint Estimation Method Based on Kalman Filter of Battery State of Charge and State of Health

“…With the continuous improvement and development of BMS technology, common battery SOC estimation methods include the charging state of capacity (SOC_charge) and the discharging state of capacity (SOC_discharge), and their advantages and disadvantages are as follows. The traditional SOC estimation methods mainly include the open circuit voltage method, ampere hour integration method, and so on [12][13][14]. The open-circuit voltage method presented by Zheng et al [12] is simple and easy to use.…”

“…However, this method is not suitable for an online calculation of a battery's SOC, because obtaining a battery's open-circuit voltage requires the battery to remain in a standing state for a long time. In reference [13], Khalid et al proposed a performance analysis of a commercial battery using a hardware-in-the-loop test-bed; as a result, the battery's voltage can be traced within a 0.04 V error after a long tracking period, and the battery's SOC can be estimated within 6% error based on an SOC-OCV method. The ampere-hour integral method proposed by Bao et al [14] is simple in its calculation and easy to implement.…”

A Cost-Effective Passive/Active Hybrid Equalizer Circuit Design

“…will influence the voltage difference of all the seriesconnected cells of the battery pack. Therefore, a battery management system (BMS) [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21] was designed to protect, monitor, and control the state of all cells of the battery pack. A good BMS can ensure safe operation, maximize the available capacity, and provide a real-time estimate of the remaining discharge capacity of the battery pack [19].…”

“…Therefore, some research uses a hardware-in-the-loop (HIL) simulation tool to test BMS. The HIL can be used to simulate string cells of a battery pack [20] to test BMS functions for cells, e.g., test passive equalizer function [21]. Briefly, HIL is a good auxiliary tool in the development stage of a BMS, which can significantly reduce the development time and testing risk of the BMS.…”

“…uses a hardware-in-the-loop (HIL) simulation tool to test BMS. The HIL can be u simulate string cells of a battery pack [20] to test BMS functions for cells, e.g., test p equalizer function [21]. Briefly, HIL is a good auxiliary tool in the development sta BMS, which can significantly reduce the development time and testing risk of the B many practical experiences, most battery pack failures are caused by the cell volta balance issue, which means the voltage difference is enormous, drastically reduci battery pack's available power, capacity, lifespan, and safety.…”