Battery technology is undergoing significant advancements due to the urgent need to combat climate change. To fully utilize batteries, monitoring and controlling their parameters, such as temperature, state-of-charge (SOC) and state-of-health (SOH), is crucial. A battery management system (BMS) with distributed sensors is used for this task but requires efficient data communication between the main controller and the subsystems.
In the realm of battery systems, Powerline Communication (PLC) is emerging as a viable alternative to traditional data cable communication and wireless technologies. PLC modulates a data signal onto existing power cables, eliminating the need for additional data cables. This approach provides flexibility, reduces space, weight, points of failure and cost by utilizing the existing battery power line. The potential for PLC specifically exists in the battery application, however, for it to become a reliable and affordable alternative, further research is needed.
This study aimed to develop a hardware system for evaluating PLC using battery applications. Prior to this, the high-frequency performance of an individual lithium-ion cell was examined. Different tests were performed to look at the influence of cell parameters such as temperature, SOC, and SOH on the high-frequency (HF) characteristics of the battery cell. With that information, a demonstrator battery network was built.
The intended PLC hardware solution was supposed to be a laboratory setup, in which flexibility and the possibility to change and analyze every part of the communication chain were more important than power consumption and a small form factor. After an initial screening of the market, no existing solution could be found that met the planned requirements. As a result, it was decided to try to design our own hardware system.
Ultimately an I/Q modulator chip was selected, because it can generate different modulation schemes over a range of frequencies. This modulator was combined with a Nucleo microcontroller board and a differential DAC to generate various PLC signals. It was assembled using prototype boards and the communication was tested. The hardware setup showed high flexibility and data rate transmission of up to 10MHz, with different modulation schemes.