感应电机最大效率控制时损耗模型研究

针对半监督学习方法存在的学习速度缓慢、不确定性递增等问题,提出一种基于极端学习机的半监督学习方法.该方法将极端学习机从监督学习模式扩展到半监督学习模式,以输出阈值向量控制标记样本的扩充程度,利用"换位"策略评估扩充标记样本中不确定性的影响.仿真结果表明,所提方法能够显著提高半监督学习的速度并有效减小对标记样本的依赖程度.

Loss model of induction motor under efficiency maximization control

Relationship between the rotor iron loss equivalent resistor and slip can be derived through analysis of iron loss of induction motor. From the relationship between the proportion of rotor iron loss as to total iron loss and the electrical angular frequency of the flux, it is shown that the effect of rotor iron loss on the efficiency of induction motor is distinct at low speed. Taking the rotor iron loss into account, a loss model of induction motor is set up. The efficiency maximization control condition for induction motor vector control drive at steady state condition is derived using the Lagrange theorem. The experimental results show that the proposed model is accurate within the whole speed range, and the efficiency maximization control condition is valid.