Impacts of Energy Storage Capacity Configuration of HPWS to Active Power Characteristics and Its Relevant Indices

Abstract

The common characteristic of solar energy and wind power are the low energy density and strong randomness.As a new form of power generation unit,which complements the characteristics of wind power generation system with that of photovoltaic generation system and energy storage device,Hybrid photovoltaic/wind power generation system with storage bank(HPWS) can decrease active power fluctuation and improve power quality as well as mitigate the influence of active power fluctuation due to intermittent power generation of wind farms and solar PV generation sytems,thus the technica characteristics,capacity configuration and control strategy of wind power generation,solar PV generation and energy storage euqipments greatly impact the overall active power characteristics of HPWS system.On the basis of analyzing structural features,methematical model and technical features of HPWS system,an optimized charging/discharging model of energy storage unit is proposed,in which the mnimum fluctuation of active power is taken as objective function and in the constraints the initial capacity of energy storage at each step and charging/discharging control storage are taken into account.Based on the proposed model,three inices,by which the active power fluctuation is checked,are put forward,and combining with other two indices that evaluate the power supply reliability of HPWS system the characteristics of overall output active power of HPWS system is comprehensively evaluated.The checking computation of actual example is verified by the simulation software programmed by Matlab,and the varying trend of active power characteristics with the scheme of energy storage capacity configuration is analyzed.