Automation of eddy current dynamometer for engine testing and calibration 2022-36-0004
The digital control of a dynamometer is essential for test of internal combustion engines, because it acts in command of the testing routine. This work consists in the PID (proportional, integrative and derivative) control of the Foucault current dynamometer, from the Institute of Technological Research - IPT. During the control development was made plant differents types, and differents controllers, that was validated by form experimental and theory. Digital controls were achieved using LabVIEW® and Simulink® software, which served to compare and simulate them, thereby making possible a validation. For the system in real-time, controlled by LabVIEW®, it was necessary to identify the dynamometer model, which corresponds to an eddy current brake, model I2D. The speed control developed by means of these tools is intended to adjust the speed of the dynamometer. In order to carry out the tests, this speed parameter must follow the desired values (set point) and maintain the relationship of electric current intensity with the throttle opening of the motor. In this way, the developed project opens up a perspective of greater reliability, that is, its responses are met in relation to the stabilization and transient of controlled values in tests performed with bench dynamometers. In the academic field, it ranges from theoretical to experimental, as it applies a scientific method to practical tests carried out in a validation instrument. Therefore, this contribution developed a digital control from the physical parameters of the project using the white box identification method, made by approximating a mathematical model of a direct current motor (DC). The black box method was also implemented, made by identifying the reaction of the dynamometer to a step response, in the experimental scope. The simulated reactions were compared with the experimental ones and showed equivalence between them.