Energy storage battery soc control

What is balancing the state-of-charge (SOC) of a battery?

Author to whom correspondence should be addressed. Battery energy storage systems are widely used in energy storage microgrids. As the index of stored energy level of a battery, balancing the State-of-Charge (SoC) can effectively restrain the circulating current between battery cells.

What is state-of-charge (SOC) in a battery energy storage system?

For a battery energy storage system (BESS), the State-of-Charge (SoC) is a key parameter. Due to the complexity of battery structure and electrochemical reaction, SoC is often difficult to obtain directly.

How does SoC affect the energy storage system?

The energy storage system is affected by SOC. The SOC of the battery and supercapacitor can be expressed in the discrete form: (4) SOC BA k + 1 = SOC BA k − T s P BA k / Q BA SOC SC k + 1 = SOC SC k − T s P SC k / Q SC In general case, the HESS is mainly composed of large-capacity batteries, so the SOC of the HESS is determined by the battery SOC.

Can a centralized SoC balancing control strategy be used for hybrid energy storage systems?

proposed a local-distributed and global-decentralized SOC balancing control strategy for hybrid series-parallel energy storage systems, which can offset the SOC of each energy storage unit (ESU) to the same value in a distributed manner. This paper also analyzes the stability of small-signal modeling, which guides parameter design.

Which SOC unit keeps a maximum charging power during SoC balancing?

More specifically, it shows that the maximum-SOC unit (i.e., unit 1) keeps a maximum discharging power during most of the SOC balancing process. At the end of the SOC balancing process, the minimum-SOC unit (i.e., unit 3) keeps a maximum charging power for a short time.

Is battery energy storage a balancing strategy?

An Improved SoC Balancing Strategy for Battery Energy Storage System in All-Electric Propulsion Ships Current Sharing Effect. J. Electr.