Recently renewable power generation is growing rapidly, due to global warming, low cost & it is environmental friendly energy source. The generation systems are either standalone or grid connected. In present-days researches are motivated on various electrical power generation from renewable sources [121,122]. PV has MPPT corresponding to climatological conditions, PV cell area and types of load [123]. In Wind turbine (WT) when wind speed varies extensively, the variable speed generation (VSG) is perceptible than fixed speed systems.
In the proposed paper PV cell [124], wind turbine [125], and battery form a hybrid micro grid [126] system.
It requires an advance technique for management and operation of electricity grid for the proper use of power. The configuration of PV array in series or parallel and their I-V & P-V characteristics are discussed. Therefore to increase the efficiency of output energy a MPPT controller is connected. Different types of MPPT algorithm have been discussed, such that open circuit voltage (OC), Incremental conductance (INC), perturbs and observation (P&O) [127,128] etc.
Among all of these methods P&O method is most popular and widely used. In this paper MPPT [128] algorithm has been implemented by using fuzzy logic control [129] to get better performance. Low and high step DC-DC converter [130] is used to increase the output voltage of hybrid renewable energy source in steps. To protect the sensitive load from voltage disturbances such as sag, swell and flickers dynamic voltage restorer (DVR) is proposed. Different DVR [131] circuit topologies for different levels of inverters are discussed. STATCOM [132] is mainly used for improvement of reactive power in distribution system and to stabilize the transmission system.
Unified power quality controller (UPQC) [133] is used in distribution system. There are unbalanced voltage, current and distortion in distribution system. UPQC is one where series and shunt active power filter (APF) [134] operate together for compensating the power quality problem. There are various techniques of pulse width modulation such as Space vector pulse width modulation [135], single pulse width modulation, sinusoidal pulse width modulation have been explained. PSO algorithm is applicable for digital signal processing implementation switching strategy with better lower order harmonics control compare to above methods. Minimization of THD for multilevel inverter i.e. with the increase of level of inverter THD is reduced is as explained but switching loss is increased.