Compared to state of the art solutions, the proposed series LC resonant circuit eliminates the complexity of multi-winding transformers and it can balance series connected energy storage devices in a short time by transporting energy successively between the cells having highest voltage difference.
The resonant tank stores the excess energy from the strong cell and releases this energy to the weak cell to the battery cell string. Thus, all switches are turned ON/OFF in ZCS condition for this balancing circuit to have less power loss and take less balancing time. Fig. 1. schematic diagram proposes a cell balancing circuit. 2.2.
Theoretically, our circuit equalizes the cell voltage in 11.357 V but it was equalizing in 11.35 V. Yu et al. proposed single resonant converter based equalization circuit. They used 300F SC. The initial voltage of these SC are 2.5 V, 2.3 V and 2.0 V. After 15 min this equalization does not equalize the SC voltage.
Yu et al. proposed single resonant converter based equalization circuit. They used 300F SC. The initial voltage of these SC are 2.5 V, 2.3 V and 2.0 V. After 15 min this equalization does not equalize the SC voltage. Theoretically, this circuit equalizes the cell voltage in 2.267 V but it has 10 mV gaps.
Here, the resonant frequency ω r = 1 LC and α = R 2 L is the damping factor of the resonant frequency, and z 1 & z 2 are natural frequencies. From series RLC circuit, Eq.
For the series resonant circuit, C and L were determined as 200 μF and 100 μH. For the experimental setup commercially available SMD capacitor, C (KTJ250B107M76BFT00), and a small parasitic resistance-formed inductor, L (SDR0403-BOURNS), were used.