The renewable energy-based distributed generation (DG) implementation in power systems has been an active research area during the last few decades due to several environmental, economic and political factors. Although the integration of DG offers many advantages, several concerns, including protection schemes in systems with the possibility of bi-directional power flow, are raised. Thus, new protection schemes are strongly required in power systems with a significant presence of DG. In this study, an adaptive protection strategy for a distribution system with DG integration is proposed. The proposed strategy considers both grid-connected and islanded operating modes, while the adaptive operation of the protection is dynamically realized considering the availability of DG power production (related to faults or meteorological conditions) in each time step. Besides, the modular structure and fast response of the proposed strategy is validated via simulations conducted on the IEEE 13-node test system.

Laser power transfer (LPT) is one of the leading technologies in long-distance power transmission with its advantages such as enabling high power transmission and suitability for mobile applications. The transmitter part, which includes the laser diode (LD) and the driving circuit, directly affects system efficiency. Continuous wave (CW) lasers are used in studies due to their high power and continuous radiation. However, one of the main disadvantage of the mentioned system is the high cost of LD. In this study, the use of pulsed LDs in LPT applications is proposed because of their small size and low cost. On the other hand, appropriate operating point of pulsed LD is a missing information in literature. In order to contribute literature with this information, the pulsed LD is used for LPT and the effect of driving voltage amplitudes, frequencies, and duty cycles are analyzed to demonstrate the importance of determining the appropriate operating point of the pulsed LD and that pulsed LDs can be used in LPT.

Grid-enabled vehicles (GEVs) such as plug-in electric vehicles present environmental and energy sustainability advantages compared to conventional vehicles. GEV runs solely on power generated by its own battery group, which supplies power to its electric motor. This battery group can be charged from external electric sources. Nowadays, the interaction of GEV with the power grid is unidirectional by the charging process. However, GEV can be operated bi-directionally by modifying its power unit. In such operating conditions, GEV can operate as an uninterruptible power supply (UPS) and satisfy a portion or the total energy demand of the consumption center independent from utility grid, which is known as vehicle-to-home (V2H). In this paper, a power unit is developed for GEVs in the laboratory to conduct simulation and experimental studies to test the performance of GEVs as a UPS unit in V2H mode at the time of need. The activation and deactivation of the power unit and islanding protection unit are examined when energy is interrupted.