This paper introduces scaling-factor and design guidelines for shielded-capacitive power transfer (shielded-CPT) systems, offering a simplified design process, coupling-structure optimization, and consideration of safety. A novel scaling-factor-analysis method is proposed by determining the configuration of the coupling structure that improves system safety and increases operating efficiency while minimizing the gap between the shield and the coupler plate. The inductor-series resistance is also analyzed to study the loss efficiency in the shielded-CPT system. The relationship among the shield-coupler gap, distance between the couplers, conductive-plate size, and delivered power is examined and presented. The proposed method is validated by implementing the shielded-CPT system with hardware and the result suggests that the proposed method can be used to design shielded-CPT systems with scaling-factor and safety considerations.

Due to the high electricity demand and the decreasing of fossil fuel sources, most of the countries around the world goes to renewable energy such as wind, tidal and photovoltaic (PV) for electricity generation. Among these, the study of PV as an alternative source for electricity generation has gain wide attention. One of the important aspects that should be considered in PV application is the use of grid connected multilevel inverter. This work focuses on three phase diode clamped multilevel inverter, capacitor clamped multilevel inverter and H-cascaded bridge multilevel inverter for connecting grid and PV application. These three types of multilevel inverters were simulated in Matlab-Simulink environment and a multicarrier pulse width modulation (PWM) was used for the control methods. The output waveforms of multilevel inverters are presented and comparison between these are given. The best topology for a grid connected multilevel inverter for PV application is recommended.

This paper present an approach to estimate the customer load confidence interval using statistical distribution model. Time series data of load profile in the utility of Malaysia was analyze and this data was fit with two statistical distribution models, namely the normal and log-normal distribution. Goodness of fit test was performed in the selection of best model. Result shows that the customer load consumption for each seven days can be model using both distributions. An estimated 90%, 95% and 99% customer load confidence interval was done via both distribution models.

A capacitive power transfer (CPT) system wirelessly transfers energy between coupling plates and performance issues related to CPT systems are resonance conditions, matching impedance, voltage stress, and power loss. A generalized circuit model is proposed for shielded capacitive power transfer (S-CPT) using an algebraic method. The proposed generalized S-CPT model is analyzed based on the symmetric and asymmetric configurations, and the relationship between the parameters of S-CPT is obtained with respect to the resonance condition, matching impedance, voltage stress, and efficiency. The best configuration of a symmetric S-CPT is recommended, and an asymmetric S-CPT is proposed based on the analysis results. Asymmetric-S-CPT hardware was constructed and demonstrated an operating frequency of 13.56 MHz. The hardware experimental result shows the validity and effectiveness of the proposed generalized model for designing S-CPT.

A shielded capacitive power transfer (S-CPT), a method of wireless power transmission (WPT) in which using electric field resonant (EFR) with an improved ground stability is proposed in this paper. The feature of ground stability can be succeeded simultaneously by using 1:1 Ruthroff transmission line transformer (TLT) balun. The unbalanced condition from the power source is converted to the balanced condition by the transformer. The analytical study of the shield plate voltage stability is also described both the simulation and hardware experiment. By using Spice software, with the proposed system, the simulation results show the constant zero voltage value from the shield plate to the ground. An experiment was conducted for validations of the proposed S-CPT with balun at 6.78 MHz resonant frequency. A measured shield voltage was compared under the unbalanced and balanced condition with the value of 20 V (peak to peak) and steadily of 5 V (peak to peak). An enhancement of the shield voltage ground stability is developed successfully with 75% of swing voltage reduced by the implementation of the TLT balun.

Grounding of electrical installation is primarily concern with ensuring safety. The main purpose of grounding is to channel the fault current straightly to earth. To produce a good grounding system, the value of earth resistance must be reduce as low as possible. Otherwise, current may flow through to those who touch the damage electrical equipment instead of flowing through grounding system. In this project, a variety diameter of copper rod and galvanized iron rod were installed to build grounding system. The aim of this project is to find if there exists significance difference in the value of resistance when different diameter and different type of rod were used. Single rod testing and parallel rod testing were performed with fall of potential method to measure the value of earth resistance. Result shows that different types of rod with different diameter size produce different resistivity value which also depends on installation technique and soil condition.