Central energy management method for photovoltaic DC micro‐grid system based on power tracking control

Abstract

To reduce the impact of high penetration of renewable energy on the utility grid and suppress the influence of microgrid power fluctuation on power quality, a power tracking control strategy for DC micro-grid has been studied. Furthermore, a central energy management method (CEMM) based on this control strategy has been designed. The DC micro-grid, which contains renewable energy and hybrid energy storage unit, is used to build a complete control system model according to the distributed power supply and its control system model. The power tracking control strategy has been analysed and designed based on frequency domain method. With the designed control strategy, the system can realise coordinated operation of the hybrid energy storage unit by absorbing the load power fluctuation within different frequency range. Furthermore, based on the CEMM, the system is controlled to absorb/deliver predefined amount of power from/to the utility grid under grid-connected mode. In this way, smooth switching between different modes and the stable operation of the micro-grid are realised. Finally, the function of the system is verified with an emulated DC micro-grid system.

Effective Management System for Solar PV Using Real-Time Data with Hybrid Energy Storage System

“…However, such collaboration raises numerous new challenges. Various power-sharing strategies in the literature, addressing the above-mentioned issues are discussed below [14][15][16][17][18][19][20][21].…”

“…In [19], an energy management system with storage describes the stored energy created by DG units or during the time where power from the network is most economical. A central EMS for DC µG was proposed in [20]. The advantage of this control is to decrease the effect of the high penetration of sustainable power source on the utility lattice and smoothen the impact of µG control change on power quality dependent on central EMS for DC µG scale framework.…”

Control strategy to improve load/power sharing, DC bus voltage restoration, and batteries SOC balancing in a DC microgrid

“…Hence, these systems are not suitable for geographically dispersed microgrids. However, their response is desire where the units' distances are low [6][7][8][9][10][11][12].…”

An Anatomization of Microgrids

“…Switching losses is reduced and parasitic parameters can also be mitigated [21] LCL inverter Less device and switching loss, high switching speed and temperature stability [22] There are three modes of operation of DC/DC converter.They are i) battery and UCif power demand is not met by UC then the remaining power is supplied by the battery. ii) At low loads the battery supplies the power to the load while the UC is getting charged.…”