Voltage regulator for automobile alternator

Abstract

The main task of the project is to analyze the application of a voltage regulator for automobile alternator specified to car. The electrical system of car consists of the battery; starter motor and the charging system were also studied. A voltage regulator is an electrical regulator designed to automatically maintain a constant voltage level. An alternator is an electromechanical device that converts mechanical energy to alternating current electrical energy. A prototype of voltage regulator circuit is inspired from Jorg’s Motorcycle Pages: Voltage Regulator was constructed and tested to assure it is functional as stated in the journal. Experiments of measuring alternator output voltages and output currents filtered by the voltage regulator was ideally to compare the results gained with theory and Jorg’s experiment results were done. This project experiment consists of six parts; maximum speed measurement of the three phase induction motor and alternator, measurement of output voltage with no regulator, three phase induction motor speed and alternator speed, measurement of regulated output voltage and field current, measurement of regulated output voltage connected to one load (12V/10W lamp) and the measurement of field current, measurement of regulated output voltage connected to two loads (12V/10W lamp) and the measurement of field current, and a measurement of the actual car battery. As a result, it is found that the output voltage of alternator is related to its speed. Faster spins of rotor produces higher voltage level. A car voltage regulator regulates output voltage from alternator to a value needed and remain constant. The alternator produces more current to keep the voltage up if the voltage starts to fall below the target voltage. Transistor (T2) used for experiment circuit is a different model to the transistor (T2) used by Jorg [3]. This gives a different value to the experiment results with both expected results but does not differ a lot. The prototype voltage regulator is a successful in its operation.