A novel ADRC control structure which employs only three first-order ADRCs is presented for the speed control of induction motor drives, moreover, compared with the existing ADRC based speed control structures there is no need to estimate the rotor flux. As a result, the runtime of the proposed ADRC control algorithm is shorter than ever and the implementation of it on DSPs is easier than ever. The simulation results show that the proposed control scheme still can overcome the side-effects of internal disturbance and external disturbance, such as the load disturbances, the motor's parameter variations and the modeling error etc. as good as other robust control schemes which employ higher order ADRCs. Furthermore, a TMS320F2812 DSP based prototype using the proposed control scheme was developed. The experimental results show that the robustness of the proposed ADRC system are obviously better than the conventional PI system when various disturbances occur, and the scheme is feasible and effective.1展开▼