A survey on power management strategies of hybrid energy systems in microgrid

Abstract

The power generation through renewable energy resources is increasing vastly, Solar energy and Wind Energy are the most abundantly available renewable energy resources. The growth of small scale distributed grid networks increasing rapidly in the modern power systems and Distributed Generation (DG) plays a predominant role. Microgrid is one among the emerging techniques in power systems. Power Management is mainly required to have control over the real and reactive power of individual DG and for smooth operation, maintaining stability and reliability. This paper presents a survey of the research works already reported focusing on power management of hybrid energy systems such as mainly solar and wind systems in microgrid. Six different approaches have been studied in detail for AC,DC and hybrid AC/DC microgrid.

Modelling, Design and Control of a Standalone Hybrid PV-Wind Micro-Grid System

“…It can be observed from Figure 5 that λ needs to be maintained at an optimal value for all wind speeds-to run the WECS with maximum C p value [34][35][36][37][38][39][40]. This can be done only using variable speed operation with DFIG or PMSG where the rotor speed of the turbine can be adjusted at variable wind speed [9,[41][42][43][44][45]. Pitch angle control is usually used in large scale wind systems to fix the output power of the wind turbines at a specific limit, especially at high wind speed [28,46].…”

“…Different topologies and configurations of grid-connected PV system inverters are discussed in detail in [9]. The authors in [10] use a two-level Neutral Point Coupling (NPC) inverter for a hybrid PV/battery system.…”

“…Additional articles in the literature are mainly focused on integration between renewable and traditional resources, performance assessment, and converter design of a specific HES [6][7][8][9][10]. The Smart Hybrid Energy System (SHES) is an alternate option proposed by the authors of [6], which attempts to replace the present diesel generator with an integrated diesel-solar power generation system.…”

“…Droop control can be used for both DC and AC sub-grids or both [11][12][13][14][15]. If the latter approach is used, an interlinking between the two sub-grids is mainly used to handle the case when any sub-grid failure occurs due to over-stress, keeping individual source variations as small as possible [9].…”

Total power deficiency estimation of isolated power system network using full-state observer method

“…The same situation also applied to the network with local generator that has disconnected from the utility supply due to some contingencies problem. This situation is considerable as islandic condition and the network is very sensitive towards any disturbance due to the mixed energy demand and sources [1]- [3]. The stability condition is achieved when the dynamical behavior in the generation side is able to sustain for any level of demand and ensured the dynamical frequency network within the permissible level.…”