Research About The Loss And Heat Of The Damper System In Tubular Hydrogenerator Based On The Calculation Of Electromagnetic Field And Temperature Field

The damper winding is one of the key components of hydrogenerator. It plays an important role for the safety and stability of generator and power system. The tubular hydrogenerator is a good type of generators which is suitable for exploiting and utilizing the hydraulic resource with low water head and large flowrate. It has been replacing the traditional axial flowing hydrogenerator in the power station whose water head is lower than 20m, and it has achieved great progress in our country in recent years. However, the electromagnetic design and cool design of the tubular hydrogenerator are difficult because of its limited inner space. With the increase of demand and unit capacity of the tubular hydrogenerator in operation, the damper bars of some large tubular hydrogenerators happened heavy brokendown failures by high temperature, and the characters of these failures were similar. It leads to the importance and exigence for the research of loss and heat of the damper system in tubular hydrogenerator.By the method of numerical computation and simulation, according to the theories of electromagnetic field and temperature field, combining with the practicality of engineering, a 2D nonlinear transient electromagnetic field finite element model of tubular hydrogenerator is established, an improved thermal-path model of rotor system is proposed, and a 3D temperature field finite element model, considering the rotor's anisotropy of heat conduction, is built up in this dissertation. Furthermore, aiming at the different operating conditions, structure and materials, a large quantity of calculation, comparison and analysis about the current, electromagnetic force and temperature of damper winding are carried out with the commercial software FLUX and ANSYS. The results indicate that the eddy currents in each damper bar are unequal, the load conditions and the structure parameters are the main factors to influence the loss and the heat of damper system, and the highest temperature of the damper bar occurs at the lee side of the rotor. The calculation results accord with the actual condition of the failure generators.The research of the dissertation provides abundant date for the optimization design of the tubular hydrogenerator damper system and has important reference value for the design of the pole shoes and damper winding.