Current sensorless method based on field-oriented control in induction motor drive

Abstract

This paper describes an improving field- oriented control (FOC) in the induction motor drive (IMD) without using current sensors. The proposed current sensorless (CSL) method has achieved high performance for the speed control by the FOC technique in the IMD system. The differential equations based on state variables of stator and rotor current are used to calculate the estimated current for the FOC loop. The control voltage in the FOC loop is proposed to replace the measured voltage signal in estimation algorithms. This method can be used for non-current sensor applications to reduce the manufacturing cost or for the reconfiguration phase of the fault- tolerant control (FTC) technique. MATLAB/Simulink software is used to implement the simulations in many different operating conditions at the low- speed range. The digital signal processing (DSP) eZdsp TMS320F28335 is used to do the experiments. The simulation results and experimental results have demonstrated the possibility of using the proposed method to control the IMD without current sensors.