To Observe Stability in the Operation of the DC Motor by Incorporating Uncertainity through Fuzzy Logic

Abstract

Growing need of industry for higher productivity is placing new demands on mechanisms connected with electrical motors. They lead to different problems in work operation due to fast dynamics and instability. The stability of the system is essential to work at desired set targets. The non-linear effects caused by a motor frequently reduce stability, which reduces the controller’s ability to maintain speed at set points. Hence the flexibility of a mechanism and its control is very important. The very basic approach in control system engineering is to assume that the mechanism connected to motor is rigid. Hence the variations in set speed targets or any other apparatus connected to the motor are taken into account. This may reduce the ability of a dc machine system to carry out its assignment at set speed. It is more important to know how the mechanism, or in other words the load on the motor behaves. Anon-linear load control method for dc motor is developed and implemented in the thesis. The theoretical results obtained from the control design are validated with the PID model for dc speed control. Generalization of the system allows the methods derived here to be widely implemented in machine automation. The control algorithms are first designed in a specially introduced linear simulation model using simulink and fuzzy controller and then implemented. The results proved that both the controllers are capable of achieving the set speed stable targets but the technology of fuzzy logic provides better controllability at any set speed in lesser time as well as lesser spikes and fluctuations in the entire operation. The superiority of response using fuzzy logic controller over conventional as well as PID based controllers has been proved. The dc motor is such a drive which is perhaps more often used in all industrial processes including electrical, mechanical, construction, petroleum industry, power sectors, development sites, etc. so the controlled stable operation of this drive attracts the researchers always, still keeping more and more future scope in it.