Energy management and control optimization method based on composite energy storage

Abstract

The invention provides a composite energy storage system, which consists of a supercapacitor and a storage battery, wherein the composite energy storage formed by the supercapacitor and the storage battery has both power type and energy type characteristics; through the combined use, the charging and discharging times of the storage battery can be effectively reduced; in addition, the utilization rate of the energy storage system can be improved. According to an energy management and control optimization method matched with the composite energy storage, the total power of the composite energy storage is distributed through a low-pass filter, so that the supercapacitor and the storage battery respectively share a high-frequency component and a low-frequency component in the fluctuating power; through the two-way DC / DC1 converter constant-power control on the storage battery, the two-way DC / DC2 converter constant bus voltage control on the supercapacitor, and control strategies of the two-way DC / AC converter, the network loss of a power distribution network is reduced; the utilization efficiency of new energy sources is improved; the power fluctuation during micro power grid interconnection is effectively inhibited; the electric energy quality of a region electric network is improved; in an offline state, the stability of the voltage and the frequency of a micro power grid system can be ensured; the power balance generated during grid connection / off-grid switching is fast compensated.

Description

technical field [0001] The invention belongs to the field of new energy sources in power systems, and is an application of energy storage technology in new energy sources in power systems, specifically an energy management and control optimization method based on composite energy storage. Background technique [0002] Under the dual pressure of environmental pollution and fossil energy crisis, distributed power generation technologies such as wind power and photovoltaics have developed rapidly, and their role in power supply and low-carbon life is becoming more and more obvious. However, wind power and photovoltaic power generation are affected by the external environment, and have random and intermittent characteristics. If they are directly connected to the grid, they will seriously affect the power quality and reliability of the grid. Therefore, energy storage is needed as an energy buffer to ensure the safety and stability of the system. run. [0003] Distributed power ...

AI Technical Summary

Problems solved by technology

However, judging from the current development of energy storage technology, there is no single energy storage with the characteristics of high power density, high energy density, fast response speed, and long cycle life, so it is urgent to explore a functionally complementary energy storage system. composite energy storage

[0005] Considering the characteristics, battery energy storage has high energy density, low self-loss, and long energy storage time, but its power density is low, its cycle life is short, and its response speed is slow; supercapacitors, superconducting magnets, and flywheels have high energy storage power density, Fast response, long cycle life, and high output power, but its energy density is low, and self-loss is large during the energy storage process, so it is not suitable for long-term energy storage

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