Dynamic and Steady Behavior of Harmonic Filter for Compensating Resonance in Mining Systems

Process integration and automation in mining facilities require systems engineering involving electronics, information technologies, telecommunication, computer-based devices and power electronics control for a broad range of functions. Electronics controllability has evolved with power converter-based systems for material handling and mineral ore processing. However, power converters introduce harmonics and EMC/EMI emissions, affecting the reliability of sensitive and important electronic systems, stating a current challenge for a proper design of electrical systems in mining facilities, because increasing complexity due to combination and interaction of weak networks, high-power equipment, variable structure and non-linear loads with harmonic current injections. Harmonic filters are commonly used to provide power factor correction and limiting the harmonic distortions. This paper highlight the capability of harmonic filters to give a stationary and dynamic behavior that can be employed for compensating resonances of electrical systems in order to avoid unwanted transient phenomena like overvoltages. Modeling and simulation results obtained for a typical system with switching operations depict the good correlation between steady and transient behavior, supporting the results given by tools intended for stationary analysis of harmonics performance. Different operating conditions of an industrial power system given by variable topology, multiple harmonic injections and loading factor should be taken into account for the proper design of harmonic filters systems. This work presents a methodology for supporting the risk assessment and decision making process at the design stage of power systems, in order to avoid failures, improving design and reliability.