Researches On The Influences Of Damper Windings On Electromagnetic Field And Rotor Temperature Field In Pumped Storage Machines

It is effective to enhance the economy and reliability of power system with pumped storage power stations for regulating power system load. Pumped storage machines are important parts of pumped storage power station. As an important component of this kind of machines, damper windings can not only inhibit the magnetic field mutation and rotor oscillation, but also provide the starting torque for asynchronous starting of a pumped storage machines in motor working conditions. The shape and distribution of damper bars influence the electromagnetic performance of the machine and the temperature rise of the rotor parts, therefore, it is significant that research on the influences of damper windings on electromagnetic parameters and temperature distribution of electrical machines.Combining the actual structure size and rated parameters of a pumped storage machine, based on the theory of electromagnetic field, the2D finite element model was built, and the reactance parameters and the eddy loss of damper windings were calculated after solving the electromagnetic field inside the motor, the additional loss inside the rotor was calculated with the analytic formula, the loss distribution on the pole surface and damper windings was obtained. Then, comparing a motor with damper windings and a motor without damper windings, discussed the effects on loss distribution inside the rotor and the reactance parameters of a-motor with damper windings, the changes of eddy loss of damper windings when the motor operating with asymmetric working conditions were obtained. Analyzed in detail the related influences of the changes of damper winding pitch and diameter. The conclusion could provide design basis of damper windings of pumped storage machines. Finally, the3D coupled temperature field and fluid field calculation model was built, the calculation and analysis of temperature distribution of the structure and fluid inside the rotor when pumped storage machines operating in generator and motor working conditions under rated load are obtained, the calculation was verified efficiency after compared with measured values. On this basis, the reactance parameters, distribution of the temperature and eddy loss inside the rotor before and after the broken fault of damper bars was analyzed and compared.