Analysis of Load Fluctuation Effect on the Excitation Current of the Three-Phase Synchronous Generator at the Diesel Power Plant

The excitation system is one of the components which uses a DC power supply as a reinforcement of the synchronous generator so that the generator can produce electric energy with the generator output voltage depending on the magnitude of current excitation. The stability of the voltage terminal or output voltage generator is strongly influenced by changes in current excitation. The generator is one type of electric machine which is used to convert mechanical energy into electrical energy. In a generator, mechanical energy obtained from the first mover can be turbines, propellers and diesel engines. In the large power plants, one conversion tool that is often used is a three-phase synchronous generator. The synchronous generator is a synchronous generator with specification 1,030 KVA, 420 V. Operation of the generator requires and stability so that the condition of the generator remains in optimal condition. The stability of the generator can be affected by namely loads, excitation current, power factor, and the round number generator. Change due to the voltage terminal connected to the load generator will cause instability. This study aims to look at examine changes electricity to the excitation current in the synchronous generator three-phase. From the analysis found that the increasing burden of the electromotive force (EMF) induction will also rise and the flow field where the EMF induction also increased in the can at the time of peak load power factor is lagging 481.68 Volt, excitation current 144.89 Ampere and the field current 510.52 Ampere, EMF Induction on leading power factor is 469.10 Volt, excitation current 136.65 Ampere and the field current 470.55 Ampere. The percentage value of voltage fluctuation in the synchronous generator of the diesel power plant MIGAS during the observe reached between numbers - 4.30 % up to numbers -4.70 %. In the electricity supply system, the average electrical voltage has a varying supply point, that is according to national power company standard +5% and -10% but on the standard, ANSI C 84.1 is preferred in +4% and -10%.