Abstract：The accurate calculation of electromagnetic torque is very important for stability analysis of generator and power system. In order to compare the calculation precision and applicability of different methods, the calculation formulas based on the Maxwell stress method are deduced on three kinds of traditional integral paths. Then, taking 300MW turbo-generator as example, the relative errors by means of seven electromagnetic torque calculation methods including the traditional Maxwell stress method, the improved Maxwell stress method, the local Jacobin derivative method and so on are studied and compared under different air gap mesh strategies and load conditions. The study shows that the shape of integration path have little effect on the calculation results of the traditional Maxwell stress method while the integration path is located on the same air gap layer. The methods based on virtual work principle are more easily affected by the gap mesh strategy under light loads. Accordingly, the Maxwell stress method should be taken under light load conditions.
康锦萍李志强刘晓芳王靖. 汽轮发电机电磁转矩计算方法的对比[J]. 电工技术学报, 2009, 24(9): 38-43.
Kang Jinping Li Zhiqiang Liu Xiaofang Wang Jing. Comparison of Calculation Methods of Electromagnetic Torque for Turbo-Generators. Transactions of China Electrotechnical Society, 2009, 24(9): 38-43.
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