Controle PID robusto projetado via LMI aplicado a um motor de corrente contínua

Abstract

In modern industry, the DC motor is widely used, having easy operation and control. However, in many cases, it’s parameters may suffer changes over time due to several factors, such as wear and environmental conditions, so, a previously designed control system may lose efficiency and even become unstable. Considering a PID controller (Proportional, Integral and Derivative), the most used control structure in current industry, this work presents a way to treat parameter variation in a PID control system applied to a DC motor. The controller gains, Kp, Ki and Kd are obtained through LMIs (Linear Matrix Inequalities), a technique that allows the uncertain parameters approach. The decay rate and D - stability state feedback LMIs were used, introducing performance parameters to the system by pole allocation. This work shows the process of obtaining the system transfer function, robust control system modeling and it’s implementation, validated through simulations and comparisons with performance parameters. The control system proved to be viable under different conditions, even in the case of a failed feedback operation.