There are differences in soc between battery energy storage units

What is a SoC balancing control strategy for energy storage units?

A SOC balancing control strategy for energy storage units with a voltage balance function is proposed. An analysis of SOC trends is carried out in response to the power changing of loads and micro-source. An adaptive virtual resistances algorithm is coordinated with the control strategy of VB to accelerate the balance process.

What is a control strategy for energy storage?

Compared with the traditional control strategy, the proposed control strategy can effectively balance the SOH and SOC of each energy storage unit and keeps the system's overall capacity for a longer period.

Does SoC affect the internal resistance of a battery?

Additionally, SOC affect the internal resistance of the battery. When SOC decrease to 70 %, the effectiveness of estimating internal resistance gradually diminishes in this study because of the reduction in the size of the covariance matrix in the algorithm, and the estimated internal resistance values only fluctuated slightly.

What is the difference between a battery and a Soh?

The voltage differences of the batteries with different SOHs are clearly distinguishable, and their degrees of difference vary. At the initial stage of the operating condition, the batteries have the same initial charge state and there is no inconsistency in the voltage between the batteries.

How does the SoH of a battery affect its internal parameters?

The SOH of a battery is closely related to the changes in its internal parameters. Through experiments on the hybrid pulse power characteristics (HPPC) of batteries at different lifetimes, the values of these parameters under the current SOH could be obtained.

What happens if energy storage system is operated according to equal sharing?

If the system is operated according to the traditional equal sharing control strategy, the simulation results are shown in Fig. 7 d, where the energy storage system has storage units whose health state drops to 80% after 3556 h of operation, which in turn reduces the capacity of the whole system.