Computational Comparison of AC and DC Motors to Hydrodynamic Changes in Marine Fishing Vessels

Abstract

The objective of this article is to make a comparison in a computational environment between an alternating current motor and a direct current motor is made for dynamic variations in the propulsion of an artisanal fishing boat. Initially, the boat was simulated in the Maxsurf software to obtain the dynamic behaviors for pitching, rolling, yawing, and heave motions with wind and wave perturbations for a Pierson Moskowitz spectrum. Subsequently, the motors are selected and in Matlab/Simulink software and a torque behavior required by the vessel to act on the resistance presented in each dynamic motion is proposed. This allows for analyzing the required mechanical and electrical conditions, using the curves obtained in the simulation. Finally, it is concluded that taking into account the criteria of torque, power, speed, and current, the results obtained show that the DC motor is more efficient than the three-phase AC motor for artisanal fishing vessel applications. In addition, the two motors require greater effort to overcome the disturbance related to the rolling motion in the steady-state, while in the transient state the DC motor requires a higher starting torque and the AC motor presents oscillations, which are undesirable disturbances because they produce instability in the electrical system. Additionally, it is important to take into account the energy source that feeds the motors, which can be alternating current or direct current.