Extremum Seeking Control for Performance in Rotary Drilling

Sammanfattning

As the world increasingly turns towards greener technologies, the demand for minerals has skyrocketed. This increase in demand has led to higher demands on the mining industry, and, therefore increasing requirements on the machines. To be able to meet these requirements new control strategies are needed that can provide more optimal utilization of these machines. The goal of this thesis is to investigate the possibility of using an Extremum Seeking Controller (ESC) to improve the drilling performance of one of Epiroc’s rotary drills. Extremum Seeking Control is a model-free, real-time, adaptive algorithm that can solve static optimization problems for a given objective function. To solve the problem, a literature study was conducted, after which a case study was done in which a provided simulation of Epiroc’s Pit Viper 351 drill rig was used. Before the algorithm could be implemented, a Model Predictive Controller (MPC) had to be created with which the drill system could track a given reference signal. To evaluate the ESC, experiments were done using the provided simulation which tested the algorithm for constant and varying rock conditions. The optimization problem was set up both as a single and multiobjective optimization problem. Based on the results, it was concluded that while the extremum seeking algorithm can find optimal solutions, it suffers from slow convergence times and difficulty with tuning.