【摘要】 双轴励磁同步电机(双励机)的高稳定性对建设高可靠性电网及保障要害区域的供电具有重要意义。而双励机转子上具有一套两相励磁绕组使得其磁路结构及同步电抗与普通同步电机存在差异。该文建立双励机的时步有限元模型,对比分析双励机与普通同步电机在饱和特性、磁场分布等方面的差异。采用两种方法计算双励机的同步电抗,研究了双励机单轴励磁和双轴励磁时,不同运行工况下同步电抗的差异;重点分析双励机双轴励磁时,分别选取励磁绕组轴线和励磁合成磁动势位置作为直轴时,同步电抗随功角的变化规律。最后,通过双励机模型机实验验证了计算结果的正确性。研究表明:双励机的同步电抗明显小于普通同步电机;双轴励磁时,选取不同直轴会导致同步电抗随功角的变化规律不同。更多还原

【Abstract】 The high stability of dual excited synchronous generator(DESG) is of great importance for building high reliability of power grid and guaranteeing the power supply of crucial region. However, DESG with a set of two-phase field windings is different from the traditional synchronous generator(TSG) on the magnetic circuit structure and synchronous reactance. In this paper, the time-stepping finite element model of DESG is established. The saturation characteristics and magnetic distributions of DESG are compared with those of TSG. Then, the synchronous reactance of DESG is calculated by two methods. The differences of synchronous reactance of DESG with single and dual-excitation mode are studied under different operating conditions. The variation law of synchronous reactance along with the power angle is studied by taking the axis of field winding and the position of the synthetic excitation magnetomotive force(MMF) as the direct axis. The simulation results are verified by the experiments of model machine. It is shown that the synchronous reactance of DESG is smaller than that of TSG. The different direct axis positions will result in different variation law of synchronous reactance along with the power angle.更多还原