Research on temperature rise algorithm of stator winding with transposed conductors for steam turbine generators based on nonlinear thermal network coupling model

Aiming at the problem of temperature rise calculation of stator winding with transposed conductors of turbo-generator based on thermal network method, this paper takes a 5.1 MW large turbo-generator as the research object, and establishes a thermal network method of nonlinear coupling model to calculate the temperature rise of stator winding with transposed conductors. Firstly, the heat conduction path of the stator winding with transposed conductors and the core is characterized by the node thermal conductivity matrix. Secondly, the winding resistivity coefficient is introduced to construct the loss feedback function, and the transient loss of the generator stator winding with transposed conductors is calculated by numerical method. The transient loss is applied to the thermal network of the stator winding with transposed conductors temperature rise calculation to calculate the transient temperature rise of the conductor. Finally, an iterative method is proposed to solve the temperature-loss coupling equation, which improves the speed of thermal network calculation and reduces the configuration requirements of server for high-power motor thermal network calculation. Based on the comparison of simulation results and experimental results with numerical results, the accuracy and effectiveness of the nonlinear thermal network method are verified.