Speed-sensorless induction motor control system using a rotor speed compensation with the rotor flux error

This paper proposes a speed-sensorless induction motor control system using a rotor speed compensation with the rotor flux error. The rotor flux observer using the reduced-dimensional state estimator technique instead of directly measuring the rotor flux indirectly estimates the rotor flux. The estimated rotor speed is obtained directly from the electrical frequency, the slip frequency, and the rotor speed compensation with the estimated f-axis rotor flux. To precisely estimate the rotor flux, the actual value of the stator resistance, whose actual variation is reflected, is derived. An implementation of PWM pulses using the effective space vector modulation (SVM) is briefly mentioned. For fast calculation and improved performance of the proposed algorithm, all control functions are implemented in software using a digital signal processor (DSP) with its environmental circuits. It is shown through experimental results that the proposed system gives good performance for the speed-sensorless induction motor control.