Motors are electrical devices that convert mechanical power to electrical energy. The electrical energy generation is by the rotary motion of the coils around a core. The rotary motion of the motors is as a result of magnetic fields generate by two magnets. This experiments is aimed at enabling the learner to gain an in depth understanding of the working principle of the motors and generators. The learner should also be able to observe the motors and generators in action and take some experimental reading of some of the parameters (Lang & Das, 2009).

Understanding of the working mechanism of devices such as motors and generators is important for any engineering field. Motors and generators are important engineering equipment’s used in almost every field ranging from medical, construction, automobiles and even industrial processes. Experimental setups meant to foster better understanding of these motors and generators should therefore be set up in a manner that enables the learner to get the most out of it.

According to Cheng & Gu (2010), Parameters such as torque, voltage, current and motor rotation speeds are important in understanding the devices. Measurements of these parameters under various conditions with variation of current or voltage helps the learners to understand the relationship between t5hem. An understanding of the relationship between these parameters enhances effective use of the motors for a specific task. The experiment set under consideration was therefore designed to achieve this hypothesis. The experiment requires the learners to observe and record various parameters. A better understanding of the relationships of the various data observed and recorded is enhanced by using visual presentation techniques such as graphs. Various graphs are needed for the various parameter relationships under consideration.

Motors and GeneratorsResults

Motors and Generators 1
Motors and Generators 2Motors and Generators 3

Motors and Generators 5Motors and Generators 4

Motors and Generators 7Motors and Generators 6


In any motor in the arrangement as shown in the experiment 1, when the motor turns, there is an induced voltage proportional to the speed of the motor produced as shown in figure 2. The motor similarly develops a torque proportional to the armature current flowing within the motor. This, these motor behavior can be summarized by the equations shown below.

Motors and Generators 8

Motors and Generators 9

When voltage is applied to the armature of a motor that has no loading, there is no change in the current flowing in the circuit. Therefore, due to the linear relationship between the motor speed and the armature voltage, the relationship can be represented by a straight line as shown in the graph.

Similarly, as a result of the linear relationship between voltage and the motor speed, a direct current motor can be considered to be a voltage to speed converter. When a fixed voltage is a plied to a dc motor, the voltage in the motor resistor increases as a result of increase in armature current. This results in subsequent decrease in voltage. This also results in subsequent reduction in the speed of the motor.


Motor parameters have varying relationships depending on the nature and the state of the motor. Determination of these parameters and their relationship is important in selection and fitting a particular motor to a particular task. Speed, voltage and current are the most important parameters that should be understood.


Lang, J. H., & Das, S. (2009). Motors and Generators. In Multi-Wafer Rotating MEMS Machines (pp. 325-404). Springer US.

Chen, H., & Gu, J. J. (2010). Implementation of the three-phase switched reluctance machine system for motors and generators. IEEE/ASME transactions on mechatronics15(3), 421-432.

Schubert Jr, T. F., Jacobitz, F. G., & Kim, E. M. (2009). Exploring the basic principles of electric motors and generators with a low-cost sophomore-level experiment. IEEE Transactions on Education52(1), 57-65.