This paper presents the simulation and experimental result of class-E power amplifier. It is often used in designing a high frequency ac power source because its ability to perform the conversion efficiently even at high frequencies with significant reduction of switching losses. This paper aims to compare the transmission performance of electrical power between the air core transformer and iron core transformer which the identical input voltage of 50 VAC. Both transformers are designed to step voltage up (step up transformer) ratio of 1:4.5. The Arduino microcontroller Arduino was used to generate a pulse width modulation (PWM) with operating frequency of 3.74 kHz. IC gate drive TC4422 was used to drive the IRF510 MOSFET. Based on the simulation and experimental results the power loss in air core transformer is 75 percent while power loss in iron core transformer is 0.2 percent. The maximum distance that can transmit electric power of air core transformer is 9.3 centimeters.

This Research purposes assessment of lightning performance on transmission system 69 kV in Metropolitan Electricity Authority (MEA). The case studies illustrated the lightning strike to direct top pole in order to guideline considering the critical flashover voltage value of insulator is able to withstand it and improvement lighting protection in the future. This solution analyzes using the Alternative Transient Program-Electromagnetic Transient Program (ATP-EMTP). The result found that voltage across insulator before and after improvement lightning protection by external ground wire. Factor effect to voltage across the insulators is the tower footing resistance wave of lightning current and interval between towers. It depends on relation with front time of wave. The analysis economics is very important. This Research is studying interruption cost of outage since back flashover so analysis the break even point of the installation external ground. The result found upon improvement lightning protection by installed external ground. The pay back period of that is 9 years installed ago. This result can conclusion is external ground able reduction interruption costs of outage.