Wind power plant grid-connected power smoothing method for optimizing charging and discharging of double-battery system

Abstract

The invention discloses a wind power plant grid-connected power smoothing method for optimizing charging and discharging of a double-battery system. According to the method, on the basis of wind powerultra-short-term prediction, an average wind power prediction value in a control period T is used as basic reference output power of a wind power plant, and the basic reference output power of the wind power plant in each control period T is dynamically corrected according to the charging and discharging energy imbalance degree of the double-battery system; when the dischargeable energy of the double-battery system is greater than the chargeable energy, the double-battery system is enabled to be charged less and discharged more by adjusting the basic reference output power of the wind power plant; on the contrary, when the rechargeable energy is greater than the dischargeable energy, the double-battery system is made to be discharged less and charged more, and therefore the difference ofthe charging and discharging energy of the double-battery system is reduced. According to the method, the output power of the wind power plant can meet the scheduling and grid connection requirements,meanwhile, the charge-discharge energy imbalance of the double-battery system is improved, the charge-discharge depth of each battery pack is optimized, the long-term stable operation of the system is ensured, and the method is simple, effective and convenient for practical engineering application.

Description

technical field [0001] The present invention relates to the technical field of wind power generation, in particular to a wind farm that can meet the power smoothing and dispatching requirements of a grid-connected wind farm, optimize the charging and discharging energy imbalance of the dual-battery system used, and is simple and reliable. Net power smoothing method. Background technique [0002] Wind power generation has become a new energy source of widespread concern due to its outstanding advantages such as large capacity, cleanness, and relatively low cost. However, wind power has strong intermittency and volatility, and direct grid connection will bring harm to the security and stability of the grid. It is a feasible way to smooth the grid-connected power combined with the battery energy storage system. [0003] In order to avoid the damage to battery life caused by frequent charge-discharge switching and shallow charge-discharge depth of the conventional single-batter...

AI Technical Summary

Problems solved by technology

However, due to the uncontrollable wind power and its prediction error, as well as the alternate operation of the battery packs in the dual-battery system, it is difficult for the two sets of batteries to reach the set optimal charge and discharge depth at the same time, resulting in a gap between the charge and discharge energies. Balance problem. Studies have shown that when the dual battery system is running, it is very easy to lose the wind power smoothing ability due to the large gap between the chargeable capacity and the dischargeable capacity, resulting in an extreme imbalance of charge and discharge energy.

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