This study proposes a flexible, compact, efficient, and cost effective electric vehicle-to-electric vehicle charge sharing solution that will lead to faster and wider customer adoption of electric vehicles (EVs) as an alternative to current grid-to-vehicle charging methodologies. The energy will be transferred between EVs using a bidirectional dc-dc converter in a conductive way, which can take place at parking lots of workplaces, campuses, or residential premises and highways. The proposed design provides compact infrastructure, wide input and output voltage ranges with bidirectional buck-boost operation, and fast power transfer compared to Level 2 charging stations. A complete design comparison between Si and SiC based converters has been carried out based on the available power modules and magnetic cores. The comparison demonstrates the effect of switching frequency and switch selection on the size of passive components, the converter efficiency, and the power density of the converter. The developed study evaluated three different bidirectional dc-dc converter topologies and validated the developed prototype with experimental results.

The tradeoff between the operating cost and the reliability of microgrids imposes challenges of having cost-effective power dispatch and reliable operations. The work presented in this paper optimally solves this issue in a microgrid that contains PV, dispatchable generator, and storage battery. Flexible control algorithms are developed to enable high penetration of PV power in islanded microgrids such that the challenge of having a cost-effective and reliable operation can be mitigated. This is achieved by creating a power flow optimization framework that considers all variables associated with the system operation. Particle swarm optimization (PSO) is utilized to effectively optimize the power flow among the integrated sources and to dynamically schedule the battery state of charge (SOC). The proposed controller of each source works to fulfill the requirements of the optimization. The energy index of reliability (EIR) is employed as a direct measure to quantify the reliability level of the microgrid. The effectiveness of the proposed approach is demonstrated by simulations and validated by experimental studies.

The objective of this paper is to determine the location and size of the renewable energy sources (RESs) to be installed in microgrid networks having multiple distributed generators (DGs). Since RESs have faster dynamics and low inertia, microgrid sources could encounter large disturbances in their power productions when RES is deployed. As the magnitude of the disturbances exceeds a certain limit, the stable operation of the microgrid can be comprimised. In this study, the impact of installing a certain capacity of RES at specific nodes on the microgrid is numerically evaluated. A novel methodology is developed to accurately determine the location and size of a newly installed RES in a microgrid. The proposed methodology considers the complete system dynamics in the process of locating and sizing the installed RES. The stability of the microgrid is examined using a modified microgrid load flow model. The proposed method automatically checks for the optimum RES placement to ensure minimal effect on microgrid stability. The effectiveness of the proposed methodology is verified experimentally on a microgrid testbed.

Interfacing a weak grid imposes challenges on distributed generators (DGs). These challenges include transient frequency and voltage dynamics that can destabilize the system. Accordingly, this paper investigates the grid stiffness based on different scenarios and the dynamics of a grid feeding DG connected to a weak grid. Moreover, the dynamic effects of the physical and control parameters on the system’s stability are deeply analyzed and evaluated. Specifically, complete mathematical models and graphical representation are carried out to precisely examine the impact of the system parameters on the stability and performance of the DG. Therefore, stable deployment of renewable energy resources into power networks can be achieved as well as an efficient and robust performance of DGs can be ensured when connected to weak grids. The obtained results show the importance of the performed study in optimal sizing and designing the output filter of the inverter and the impact of tuning the control parameters on the system dynamics. As a result, a proper design of system physical and control parameters can be accurately achieved considering all factors affect the system performance. The paper also conducts detailed and elaborated analyses and simulations to evaluate the performance of a PI-controlled RC damped inverter connected to a weak grid. The proposed filter design of the interfacing inverter can significantly extend the integration of DGs into microgrids without requiring complex control schemes or oversized components.