Research On Bearing Temperature Field Of Wind Power Generator

Temperature rise is the primary factor affecting the normal operation of the wind generator set.In order to ensure the smooth operation,it is required to clarify the temperature rise internal,and take it under the control to a reasonable range,while among which the bearing working condition is the key factors that affect the temperature changes.Therefore,it is extremely significant to analyze the bearing temperature field of wind generator.In this paper,double-fed wind generator bearing is the main research object,while equivalent thermal grid method network and finite element are used to analyze temperature field of the bearing and the generator,as well as the rule of generator heat to the bearing’s temperature changes.Firstly,the equivalent thermal grid method is used to study the temperature field of the wind generator and its bearing.On the basis of complicated working conditions of wind generator and heat dissipation mechanism,the paper establishes the three-dimensional model of internal heat dissipation performance and that of generator bearing,also the equivalent thermal grid model of bearing temperature rise is established and the corresponding numeric value of points is calculated.At the same time,the paper combines bearing thermal grid model with generator thermal grid model,writes the calculation program on generator temperature field,deduces the heat balance equations through the model and calculates the temperature on the various points in the generator as well as the effect of heating the generator to the bearing temperature rise.Secondly,according to the Hertz Contact Theory,the paper studies the friction heat of the bearing and analyzes the temperature field by finite element method.The contact mechanics model of generator bearing is established to analyze the relation between the bearing friction torque,load,velocity of movement with the heat generated by bearing,on the basis of that,the internal heat calculation model of generator bearing is established to study steady temperature distribution in the generator bearing,and then,there will be a comparison between the simulation results with the equivalent thermal network so as to analyze the variation tendency.Finally,the paper studies the coupling characteristics of generator internal heat flow and the influence of generator heat on bearing temperature rise.It looks at the basic theory of computational fluid mechanics and heat transfer,establishes the physical model of generator fluid and heat transfer coupling and divides the solving domain.Additionally,the paper establishes the internal discrete control equations based on the average temperature of the stator and rotator winding from practical data and adopts caluation method to acquire the heat as heat source,further determines the assumptions and boundary conditions of finite element simulation.After the simulation analysis and calculation to the generator at rated speed coupling,we can obtain the flow field distribution chart of fan rotation,and a generator casing,fan and other parts’ distribution in temperature field.Conducting the analysis of the bearing’s temperature rise changes under thermal coupling,we can compare the calculated results with the analysis results of thermal grid network method,.In this paper,the equivalent thermal grid method and the finite element method are used to analyze the effective of the wind generator bearing temperature field.The research results provide a calculation foundation for the research of the temperature rise of the bearing,optimization of motor bring’s temperature,the heat dissipation of the motor and the calculation of the temperature field and flow field of the same type.