DC-DC power converter controller for SOC balancing of paralleled battery system

This paper presents a DC-DC power converter control scheme and system architecture for batteries which are connected in parallel in order to maintain State-Of-Charge (SOC) balancing between batteries without the need for additional circuitries and their associated controllers. When the battery cells or battery packs are connected in parallel, it is desired to maintain SOC balancing during both charging mode and discharging mode. Using conventional balancing circuits is energy inefficient and/or might be complicated/not suitable. This paper addresses this by presenting a controller that is able to maintain a real-time natural charge balance between the in parallel connected batteries while maintaining output voltage regulation at the same time.