Analysis of Power Factor Compensation Characteristics According to Load Changes of Induction Motors in Conveyor Systems

Induction motors are often used in conveyor systems of logistics facilities because they are most efficient when operating at constant speed. Since the torque of an induction motor changes depending on the size of the load, it has the characteristic that the power factor also changes with changes in the power.<br/>Induction motors are typical inductive loads, and because they have a power factor lower than that required by power companies, they almost always require the installation of compensation devices such as capacitors. Since the load to be transported by the conveyor system varies in size and weight, the torque of the induction motor that operates it also varies from moment to moment. When the torque of an induction motor changes, the amount of reactive power required for magnetization changes little, but the change in active power changes greatly, so the change in power factor increases. Since the power factor correction of an inductive load calculates the capacitor capacity based on the rated output, it is necessary to check how the power factor changes along with whether self-excitation occurs with the originally designed capacitor when the torque changes.<br/>In this study, we determined the capacity of the electric motor that can obtain the required torque in the conveyor system using formulas such as the moment of inertia, and then determined the capacity of the electric motor that can obtain the required torque in the conveyor system and each characteristic before and after the installation of capacitor was compared and analyzed.