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In the last several decades, public interest for electric vehicles (EVs) and research initiatives for smart AC and DC microgrids have increased substantially. Although EVs can yield benefits to their use, they also present new demand and new business models for a changing power grid. Some of the challenges include stochastic demand profiles from EVs, unplanned load growth by rapid EV adoption, and potential frequency (harmonics) and voltage disturbances due to uncoordinated charging. In order to properly account for any of these problems, an accurate and validated model for EV distributions in a power grid must be established. This model (or several models) may then be used for economic and technical analyses. This paper supplies insight into the impact that EVs play in effecting critical loads in a system, and develops a theoretical model to further support a hardware in-the-loop (HIL) real time simulation of modelling and analysis of a distribution feeder with distributed energy resources (DERs) and EVs based on existing data compiled. 

This paper presents a cyber physical system implementation of an improved distributed secondary control (IDSC) scheme of islanded dc microgrid (DCMG). The IDSC scheme mitigates the hidden issues of primary control with included droop technique for the distributed generation unit (DGU) in a DCMG by providing the adjustable voltage compensation, improves voltage regulation and enhances the current sharing of all DGUs. The voltage compensation of IDSC is the resultant of two voltage components, i.e., average distributed integral voltage controller and average current controller. The dynamic consensus algorithm is used to obtain the global average values in the for distributed secondary controlusing relatively low bandwidth communication. The impact of communication time delay on the stability in IDSC based DCMG with two DGUs is presented. The performance of IDSC scheme is validated on a microgrid scenario, which includes parallel connection of four DGUs and common load. The real-time cyber physical system of DCMG is implemented on OP AL-RT test platform that combines the device layer on FPGA, control and cyber layers on CPU of OP5700 by using eFPGASim and RT-LAB. 

This paper proposes a combination of cell-level energy processing and a Cascaded H-Bridge Multilevel Inverter (CHBMLI) for medium voltage, grid connected, battery energy storage systems. One isolated converter (Dual Active Bridge DC-DC Converter) manages each cell in the Battery Module, and the combination of Battery module and converter modules are cascaded to get the multi-level ac output voltage. The operating principle and control design of cell level isolated converter with double frequency ripple power, and the control strategy of the CHBMLI are presented. The performance of the battery cell level CHBMLI system with a 9-level inverter at small scale power level is validated through the simulations in MATLAB ® /SIMULINK ® software. The configuration holds promise for improving the performance and reliability of the battery modules at the cell level while also providing cell level galvanic isolation and high ac voltage.