Application Study Of The Aggregated EVs For Primary Frequency Control In Microgrid

After nearly a century with internal combustion engines dominating the transportation sector,it now appears that electric vehicles(EVs)are on the brink of enjoying rapid development due to numerous useful features they possess,such as less operational cost and reduced carbon emissions.EVs can act as load as well as source,by utilizing the technique known as Vehicle-to-Grid or V2G.V2G technique adds key features to industrial microgrid in the form of peak shaving,voltage control and congestion management.Another feature that can be employed through V2G technique is frequency support to an industrial microgrid.The V2G control of the EVs will reduce primary frequency deviations by responding to the frequency deviation signal,i.e.the charging and discharging capacity of the EVs can be controlled in accordance with the frequency deviation signal for the generation-load mismatch control.In this context,the V2G control of EVs is similar to the frequency droop control of conventional power systems.Moreover,EVs,being a modern form of transport tools,will accommodate the travel use of EV users,which is distinct from the conventional frequency droop control that is only used for primary frequency control(PFC).The primary frequency control of an industrial microgrid and the charging for transport uses are therefore two important aspects,which need to be addressed simultaneously in the V2G control strategy.The PFC introduced by the V2G strategy,for EVs,is to improve the quality of frequency by controlling EVs' charging or discharging.For instance,when the system frequency goes downwards,increasing the power injection of EVs into the microgrid,or decreasing the power consumption of EVs from the microgrid,can prevent from a further drop of frequency.In this research,grid regulation controller and charge controller are proposed by considering different charging profiles for EVs,that are,'state of charge(SOC)of the EVs batteries'and‘varying number of electric vehicles in an EVs fleet'.These controllers provide bidirectional power flow that can ensure primary frequency control during different contingencies,which an industrial microgrid may face during a 24-hours period.And,this has been proved by the simulation results.Furthermore,simulation results also depict that by adding more EVs in fleet during V2G mode,primary frequency of an industrial microgrid can be improved up to a greater extent.Case study in this research constitutes of an industrial microgrid with different distributed energy resources,diesel generator,EVs fleet,and industrial and residential load.Test case is simulated and results are analyzed by using MATLAB/SIMULINK software.EVs have been receiving greater attention as a tool for frequency control due to their fast regulation capability.The proliferation of EVs for primary frequency regulation is hampered by the need to simultaneously maintain their state of charge levels and industrial microgrids' dispatch.The current research aims to examine the operative and dominating role of the charging station operator(CSO),along with a vehicle to grid strategy;where,indeterminate tasks are executed in the industrial microgrid without the EVs charging/discharging statistics.Role of CSO in regulation is the assignment of job inside the primary frequency control capacity of electric vehicles.Real-time rectification of programmed vehicle to grid(V2G)power ensures electric vehicles'state of charge at the desired levels.The proposed V2G strategy for primary frequency control is validated through the application of a two-area interconnected industrial micro-grid with renewable resources.Regulation specifications are communicated to EVs and CSOs through an electric vehicle aggregator in the proposed strategy.At the CSO,certain time instance is utilized for frequency regulation capacity calculation.Subsequently,the V2G power is dispatched in light of the charging demand and the frequency regulation.In the section,the research presents a novel primary frequency control through V2G strategy in an industrial microgrid,involving effective coordination of the CSO,EVs aggregator,and EVs operator.