Control method for island parallel operation based on large-capacity energy storage system

Abstract

The present invention discloses an island parallel operation control method based on a high-capacity energy storage system. the improved droop control at the operation of the energy storage system considering the storage battery charge state is employed. the control method divides the system into three operation states according to the different charge states, a hysteresis controller is employed to obtain the changing droop factor to regulate the power state of the storage battery in real time to allow the storage battery to perform charging and discharging in advance according to the state of the storage battery so as to ensure that the storage battery is located at the safe operation range and allow the charge state of the storage battery to have the effect of equal distribution of the power. The defects are overcome that the safety operation range of the charge state of a traditional battery is small, the storage battery is easy to generate the overcharge and over-discharging phenomenon and the service life of the storage battery is low.

Description

technical field [0001] The invention relates to the technical field of optimal control of energy storage systems, in particular to a control method for island parallel operation based on large-capacity energy storage systems. Background technique [0002] The depletion of fossil energy and the increasingly serious problem of global temperature change have promoted the rapid development of renewable energy grid-connected power generation technology. In recent years, the grid-connected penetration of renewable energy such as photovoltaics and wind power has been continuously enhanced. Due to the random and intermittent characteristics of the output power of distributed power generation units, in order to improve the power quality and stability of the system, it is usually configured in wind power generation systems. The high-power energy storage system constitutes a small independent autonomous microgrid. [0003] The microgrid can operate in grid-connected and islanded modes...

AI Technical Summary

Problems solved by technology

Compared with the grid-connected operation, the parallel island operation conditions of high-power battery energy storage systems are more complicated, and how to realize the power sharing control of multiple battery energy storage systems is the main key difficulty

In the traditional droop control, the system does not consider the actual state of charge of the battery, nor does it consider the safe operating range of the state of charge of the battery, which is not conducive to the equal sharing control of multiple battery energy storage systems

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