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Review on Optimization Techniques Employed in Distribution Generation Journal of Critical Reviews ISSN- 2394-5125 Vol 7, Issue 2, 2020 Review Article REVIEW ON OPTIMIZATION TECHNIQUES EMPLOYED IN DISTRIBUTION GENERATION Srikanth Goud B1, B Loveswara Rao2, B Neelima Devi3, K Suresh Kumar4, N Keerthi5 1,2,5Department of Electrical and Electronics Engineering, Koneru Lakshmaiah Education Foundation, Guntur, India 522502 3 Department of Electrical and Electronics Engineering, Nalanda Institute of Engineering and Technology, Guntur, India. 522438 1,4 Department of Electrical and Electronics Engineering, Anurag College of Engineering, Ghatkesar, India 501301 Received: 15.11.2019 Revised: 20.12.2019 Accepted: 23.01.2020 Abstract Distributed Generators are playing a vital role and had achieve lot of attention due to their greater impact on various distribution systems. This approach encourages small scale technologies to produce electricity to the need at consumer end by utilizing the renewable energy sources. Power quality and reliability of distributed power can be attained by proper placing of Distributed Generators at appropriate location. Optimization tools were predominantly increasing their importance in integration of distributed generation. This paper proposes various reviews on recent optimization techniques being used over the years to the problem solving and sizing of DG units. In contrast this paper analyses the economical, technological, environmental etc., which are rapidly growing interest on integration of distributed generation by overcoming all the challenges. At last it presents several optimization techniques of the integration of distribution generation from renewable energy sources. .Keywords: DGs, RES, Optimization Techniques © 2019 by Advance Scientific Research. This is an open-access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/) DOI: http://dx.doi.org/10.31838/jcr.07.02.117 INTRODUCTION importance which helped in proper planning and decision Renewable energy sources are inexhaustible, clean and free making like plant size, location etc., To enhance the from pollution so they are considered widely rather than fossil importance and development of RES the investment cost have fuels in distribution generation. Energy sources like solar, been reduced, and Distributed Generations are developed in wind, biomass, geothermal, ocean energy etc., among all these order to encourage huge investments by creating solar and wind energies are gaining importance in very wide competiveness for the usage of renewable energy. Distributed range applications. However, there is some drawback is that generators are optimized with a greater impact in reducing the all these sources are non linear in nature due to which technical challenges which are associated with grid maximum power generation is difficult. In order to overcome integration. Proper Location of DGs not only reduces the losses from such drawback optimization techniques were developed but improves reliability and voltage which is one important to track maximum power from these sources. Several objectives for the power utilities which are planning for new optimization techniques were proposed since 1960s and installation for generating power. gained importance in various applications like distribution generation is one among them. Increasing in demand for electricity, DGs are were widely being developed because they are installed at less risk and also Optimization technique are being rapidly growing during the change in the traditional system which transforms to a past few decades. Many recent theoretical and computational decentralised system. To achieve this various optimization algorithms have been contributed for various problem solving technique were developed with good benefits with multiple in engineering. Basically they are divided into deterministic objectives. and heuristic approaches. Deterministic approach takes advantage of the analytical properties of problem solving to In this proposed paper various existing optimization produce a sequence of points that converge to a global optimal techniques which are implemented for installation and solution. Heuristic approach is flexible and efficient but the integration of distribution generation from renewable energy quality of the produced solution cannot be guaranteed. sources. A brief of all these techniques are discussed which However, the chances of getting the global solution decreases provides information about the most effective technique can when the problem size increases. be used. The main objective of the system is to create net zero REVIEW OF OPTIMIZATION TECHNIQUES Greenhouse gas emissions by using renewable energy sources. Literature survey of various optimization techniques utilized These sources faced many challenges like intermittent in in distribution generation for various applications like nature, economic and technical issues during their initial maximum power tracking from renewable energy sources as setup. They were concentrated at only some specific locations these sources are intermittent in nature. Optimal location of where the resources were available for power generation but distribution generation and various technical issues can be resolved. Table 1 gives the analysis of various optimization they face difficulty with the distribution system which are very techniques and their performances under various parameters far away from their location. In order to overcome all such are studied. constraints optimization techniques has gained a greater Journal of critical reviews 639 REVIEW ON OPTIMIZATION TECHNIQUES EMPLOYED IN DISTRIBUTION GENERATION Table 1 Analysis of various optimization techniques “in scientific literature Starting Maximu Array Detected Processing MPPT A/D Tuning Parameter Difficulty Sensitivity m Dependent Parameter Speed requirement Tracking Voc Y A/D-D/A Y V Y Moderate Low Low N Isc Y A/D-D/A Y I Y Moderate Moderate Low N Inc Y Digital N V, I Y Varies Moderate Moderate Y RCC N Analog Y V, I N Fast Low Moderate Y P &O N A/D-D/A N V N Varies Low Moderate Y PSO N Digital N V, I Y Fast Low High Y Cuckoo N Digital N V,I Y Fast High Moderate Y GA N Digital N Varies Y Fast High Moderate Y GSA N Digital N Varies Y Fast High Moderate Y BBO N Digital N Varies Y Very Fast High High Y GW N Digital N Varies Y very Fast High High Y ESA N Digital N Varies Y Fast High High Y *Y Yes *No A Analog D Digital Incremental conductance MPPT Technique converter. In order to maintain less power loss, the size of P&O is set to a very small value. The main drawback is it fails to IC is commonly used MPPT in PV system to track maximum derive maximum power under fast change atmospheric power. It frequently Compares with the particular conditions. It’s very easy and popular technique. [25-40] conductance i.e., I/V and di/dv to the solar PV array. It computes IPV and VPV until there is no change then it do not generate the duty pulses required to the converter. The Start algorithm is as shown in figure 1 Start Evaluate V(t),I(t) False True =V 0? dc P(t))= VV((tt))*II(t) True True PP = = P P( t( ) t− ) − P P( t ( −t −1) 1) IVIV//? = =I 0? IVIV//? I 0 False P 0 True True False True False Raise in Decay in Raise in operating Decay in operating operating voltage voltage operating voltage V( t )− V ( t − 1) 0 V( t )− V ( t − 1) 0 voltage False True False True Drop in Raise in Drop in Raise in Stop Voltage Voltage Voltage Voltage Fig 1. Incremental Conductance algorithm IC is commonly used MPPT in PV system to track maximum Return power. It frequently Compares with the particular conductance i.e., I/V and di/dv to the solar PV array. It Fig. 2 Perturb and Observe algorithm computes and until there is no change then it do PSO MPPT Technique not generate the duty pulses required to the converter. The algorithm is as shown in figure 1.[1-25] PSO is an intelligent technique majorly used for evaluating optimization which functions on the movement of swarms. Perturb and Observe MPPT Technique Problem solving such as social communication is applied using Generally, MPP techniques are commonly used track PSO. It utilizes number of particles which constitute swarms maximum power from sources which are intermittent in moving in a specified search space to track the best solution. nature like renewable energy sources. P&O is most commonly Each particle tries to track its neighboring particles in the used techniques which continuously compares and computes search space which is accomplished with the best solution the reference voltages until a best value is obtained to Pbest.PSO tracks another best values among the best values generate duty pulses which is required to operate the Journal of critical reviews 640 REVIEW ON OPTIMIZATION TECHNIQUES EMPLOYED IN DISTRIBUTION GENERATION obtained which is called global best Gbest. Both the Gbest and Pbest are saved and determined by the following velocity.[15-56] Start Load Cuckoo search Parameters Velocity function: Vi( k+ 1)= V i ( k ) + t 1 i( P i − X i ( k )) + t 2 i ( G − X i ( k )) Load Generation of Host nest population Start Calculate the fitness function of the Host nest population Upload the Particles Compute fitness values for each Particle Levy flight Equation to modify nest position Move cuckoos to better environmet no Condition satisfied or not ? Verify for fitness value better yes than pBe?st no yes Result Select current fitness as new Save previous pBest pBest Nominate best particles Pbest Stop value to gBest Fig.4 Flowchart for Cuckoo MPPT Compute velocity for Each Particle By computiong the array, the data among which the highest Update its data values by using power is chosen as the best sample. Thereafter the rest of the saampled datat are made to follow to the best values. The step each particles velocity sizes are calculated by performing the Levy flight as described by equations.[56-60] no Yes tt+1 Vii= V + levy() If Target reached ? S=0 ()() Vbest − V i levy End Genetic Algorithm It is a natural computational procedure which is considered to Fig.
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