Low Speed Estimation of Sensorless DTC Induction Motor Drive Using MRAS with Neuro Fuzzy Adaptive Controller

Abstract

<p>This paper presents a closed loop Model Reference Adaptive system (MRAS) observer with artificial intelligent Nuero fuzzy controller (NFC) as the adaptation technique to mitigate the low speed estimation issues and to improvise the performance of the Sensorless Direct Torque Controlled (DTC) Induction Motor Drives (IMD). Rotor flux MRAS and reactive power MRAS with NFC is explored and detailed analysis is carried out for low speed estimation. Comparative analysis between rotor flux MRAS and reactive power MRAS with PI as well as NFC as adaptive controller is performed and results are presented in this paper. The comparative analysis among these four speed estimation methods shows that reactive power MRAS with NFC as adaptation mechanism shows reduced speed estimation error and actual speed error at steady state operating conditions when the drive is subjected to low speed operation. Simulation carried out using MATLAB-Simulink software to validate the performance of the drive especially at low speeds with rated and variable load conditions.</p>

Squirrel cage induction motor predictive direct torque control based on multi-step delay compensation

“…It can be seen from ( 9) and ( 11) that the predicted values of flux linkage and current are predicted by the current ( ) and voltage ( ) measured at the current moment and the observed flux linkage ̂( ) Yes, but due to the one-beat delay in the digital control system [9], [10], the selected voltage vector will not be updated until the next moment. Therefore, the current stator current and stator flux linkage have become ( + 1) and ̂( + 1) respectively.…”

“…In particular, literature [7] and [8] proposed a new type of control technology-model predictive direct torque control (MPDTC) technology, which is simple in principle and easy to handle nonlinear constraints, but there are a lot of online calculations in the MPDTC control process, which may cause the delay problem of the control system [4]. However, in practical applications, the rotor inductance will change with the degree of magnetic saturation of the motor, and the rotor resistance will be affected by changes in the internal temperature of the motor [9]- [13]. The deviation of the rotor time constant will lead to wrong field orientation, which will deteriorate the system control performance [14], [15].…”

“…Squirrel cage induction motor predictive direct torque control based on multi-step … (Najimaldin M. Abbas)247The torque can quickly track the reference value while keeping the stator flux amplitude constant, so the objective function is constructed[9] = | * − ( + 1)| + || * | − | ( + 1)||(13) …”

Reducing torque ripple of induction motor control via direct torque control

“…Induction motor (IM) is very commonly utilized in residential and industrial plants. As a result of its properties such as simpler construction, unexpansive, high efficiency, and low maintenance [1]- [4]. Therefore, IM has been controlled (torque or speed) and experimented in early time, in competing with DC spritely excited motor [1].…”