An Investigation into operating characteristics of DC-AC Three-Phase Essay

An Investigation into operating characteristics of DC-AC Three-Phase Generators and Motors - Essay Example In such condition the machine is called a Motor. Similarly if the field flux is present and the rotor conductors are moved inside that field an induced voltage is produced in them which produce terminal voltage i.e. electric power is generated. In such situation machine is called a Generator. In this assignment first DC series generator is examined. Then Series motor characteristics are studied. Then two types of induction motors i.e. capacitor start and cage rotor motors are studied and we find that the difference in the two motors is that of the capacitor which helps to rotate the motor shaft in the beginning when there is not enough torque to start the Motor. In all these experiments relating to motors we have considered the effects of changing load torque on speed, output power, power factor and efficiency. Objective of this assignment is to enable students to understand the basic concepts underlying the effect of increasing load on electric machines. Series Generators and different types of Motors are studied with the effects of changing loads on their characteristics. All these machines show change in their behavior when load is increased. Studying that behavior is the main Aim of this assignment. After wiring the circuit as shown in the circuit schematic, I set up DC series generator. I measured the output current using Ammeter which was connected at the output in series and voltage was measured by connecting voltmeter in parallel with the output load (R1). I varied the load R1 in small steps to obtain the given values of current which I recorded on the Ammeter. The output voltage values were recorded using voltmeter. These are given in the table below. As the field windings are in series with armature windings an increase in armature current (as load increases armature current increases) will also increase the field current which in turn will produce more induced voltage and output voltage will increase as a