Highlights A nature-inspired driven approach is proposed to optimally design off-grid microgrid. Development of a rule-based energy management scheme based on queuing theory. The optimization problem minimizes energy cost and maximizes system reliability. The proposed grasshopper optimization algorithm is compared with PSO and CSA. The performance of the microgrid has been analysed against future uncertainties.

<p>This paper reviews the improvement of grounding impedance in grounding system by means of enhancement materials. Various enhancement materials for the past 20 years will be reviewed according to their advantages and disadvantages, followed by a focus on the technique for proper measurement set up based on the standard. In addition to that, the condition of enhancement materials under high voltage exposure is reviewed. Many researchers claim that soil resistivity, moisture content, and surrounding environment are the most contributed to the grounding system specifically on the grounding impedance. Hence, the utilization of enhancement materials is essential in order to maintain the grounding system performance.</p>

This paper deals with the development of a remote operation system for residential AC power supply using medium radio frequency transmission. Application of this system is to disconnect and reconnect the electricity supply which is operated by power utility company. Radio frequency (RF) remote control consists of a transmitter and receiver, which is the main module of the developed system. The transmitter will send a control signal through the module equipment transmitting antenna and the signal will be received by the antenna radio frequency transceiver module. Then, the recipient will control the electrical signals through the contactor as an interface with all electrical equipment. The operation of this system is at a fixed frequency of 315 MHz and distance control of electrical equipment is up to 10m at open space and subject to any restriction, antenna and supply of power. The results of this system are successfully demonstrated in the prototype of the remote control system for residential AC power supply. Some modifications have been proposed to improve the function of remote control system.

A photovoltaic (PV) emulator (PVE) is essential equipment for the research and diagnostic of PV generation. It is a convenient, highly efficient, and low-cost approach when compared to controllable light sources. Nonetheless, the implementation of the partial shading capability in a PVE is highly limited in terms of efficiency, computation burned, number of power converters, and flexibility to change in the ambient condition. This paper proposes a partial shading adjuster for a PVE that can overcome the aforementioned limitations. The adjuster is applicable to the conventional PVE since it is based on an algorithm that can be added to the controller of the PVE. By adding the adjuster, the conventional PVE can emulate partial shading. The partial shading adjuster is added into a PVE that uses the direct referencing control strategy with the buck controller regulated by the proportional-integral controller. The results show that the PVE maintains its accuracy and produces a stable output voltage and current during the load changes when the adjuster is added. In conclusion, the proposed partial shading adjuster able to improve th