Design and analysis of a magnetic levitation device for deloading the thrust-bearing of vertical hydroelectric generating set

The hydroelectric generating set (HGS) is the machine that transform the water energy to power. The vertical structure is more common which is applied in large and medium-sized system. Because of great bulk, the rotating parts including generator´s rotor, macroaxis, turbine runner and spiral case are great heavy. In addition, water flow impulsing the runner will produce a down force named axial hydro-thrust. Both gravity and hydro-thrust are beared by a thrust bearing, which make it easy to damage, difficult to maintain and heavy economic burden. Electro-Magnetic method was thought to solve the questions. Magnetic levitation is used to deloading the thrust-bearing. A magnetic suspending system is designed two parts respectively with electromagnetic attractive-force (EAF) and inductive repulsive force (EIRF). This paper mainly analyzes the EAF part. A improved structures of a magnetic levitation device (MLD) for deloading the thrust-bearing is proposed. The structure principle is stated, the design method is given and characters are analyzed.