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One of the the inverter’s applications is in Variable Speed Drive (VSD) to control the speed of an induction motor by varying the voltage or the output frequency of the inverter. Induction motor reliability driven by using inverter is often affected by harmonics components of the current and voltage generated by the inverter. This phenomenon brings harmonic losses in the industry process applying VSD and induction motors, because not all inverters produce a pure sinusoidal wave. Thi paper presents the effect of harmonics on the performance of squirrel cage induction motor type i.e. the speed, torque and efficiency by conducting computer simulation and experimental test in laboratory. The increase in the value of harmonics resulting an increase in the value of speed 1.41%, an increase in the value of torque 1.81 Nm, and decreased of efficiency 1to5%, the harmonics also resulted torque ripple 2 to5 times resulting in unstable speed of motor, arising engine vibration and causing motor heating

One of hydro power plant operational problem is how to maximize available water resouces to gather optimal electric power generation. Water availability which is limited and can be stored in a reservoir will influence electrical energy generated by the plant. This paper present a new approach of short term optimization of hydro power plant operation. The objective function is to maximize energy which is produced by power plant on scheduling operation period, with consider water resource availability in reservoir as operational constraint. The optimization problem is formulated in Linear Programming Method, in which this method is a commonly used to solve optimization problem in hydro power plant. Based on simulation results on Ketenger Hydro Power Plant using water flow data on June 1st 2013 shows that this method can be used to solve hydro power plant operation optimization problem well. Electrical energy as main objective function is maximized and all prevailing constrain is satisfied. On this short term operation (24 hour) simulation, total energy can be produced is 96121,55 kWh, or 1427 kWh (1,51%) greater comparing with real generation condition with 96694 kWh.

The application of shunt capacitor is an alternative solution in improving power factor on electrical installations, so the use of electric energy become more efficient. Here we hope that capacitor will give both technical and economical benefit from decreasing power consumption and electric bill. Contributions of installing shunt capacitor to active power consumption on residential installation, which one of electrical bill has been studied.Based on experimental using 2-14 F capacitors on installation model with inductive load show that shunt capacitors decrease total apparent power (VA) up to 58% dependent of its original power factor, but increase active power consumption (up to10 W). From this, installing shunt capacitors will increase cost of kWh that consumer must paid. Application of shunt capacitors will give any benefits to residential consumer in case releasing power capacity installed.Key word: capacitor, shunt, active power, consumption