Abstract: How to effectively deal with the complex and changeable nonlinear characteristics of induction

motor is the key to give full play to the performance of motor and maintain the robustness of motor control system.

From the energy analysis，an induction motor speed control method based on passivity based iterative learning was

proposed. The P type iterative learning controller was designed to make the control performance expectant with its

self-learning ability，and further improve the robustness of the system. However，the overshoot is caused by the

excessive control of the system due to the system speed step setting. In order to restrain the overshoot of the

system，the given value of the speed was softened，the soften equation was designed，and the differential term was added to form the PD type iterative learning controller. The simulation results show that the system speed curve

response has no overshoot and the following performance is good.

      Key words: induction motor；speed control；iterative learning contro（l ILC）；passivity control