In this paper a sensorless direct torque control (DTC) scheme of permanent magnet synchronous motor (PMSM) is proposed. To improve the performance of the classical DTC a modified control scheme based on twelve sectors instead of six is presented and a comparison between the two methods is carried out. The high performance of the DTC is related to the accuracy of the flux estimation witch is aff...

In this paper, rotor bar Aluminum Loss of Squirrel Induction Motor running in steady state with full load is investigated. Multi-layered analytical model of rotor bar is employed to analyze the Aluminum loss generated by harmonic current. This model divides the rotor bar into a series of sub-layers with resistance remained constant in each sub-layer considering the skin effect. The bar loss in ...

Abstract: In this paper, an induction machine rotor speed and rotor flux control using a sensorless backstepping control scheme is discussed. The most interesting point of this technique is that it deals with the nonlinearity of a high-order system by using the virtual control variable to make this system simple, and thus the control outputs can be derived step by step through appropriate Lyapu...

In this paper, we first derive the maximum power transfer theorem for an induction motor. Then, a nonlinear indirect adaptive sensorless speed tracking controller for the motor with the maximum power transfer is proposed. In this controller, only the stator currents are assumed to be measurable. The rotor flux and speed observers are designed to relax the need of flux and speed measurement. In ...

rotor field orientation stator field orientation stator model rotor model MRAS, observers, Kalman filter parasitic properties field angle estimation Abstract — Controlled induction motor drives without mechanical speed sensors at the motor shaft have the attractions of low cost and high reliability. To replace the sensor, the information on the rotor speed is extracted from measured stator volt...

There are many sensorless schemes that have been proposed to estimate the rotor speed and position. However high frequency signal injection methods are able to detect the rotor speed and position even at zero speed whereas other schemes fail. Conventionally such methods use estimators based on the phase locked loop structure, which involves some restriction to maintain stability and track accur...

There are several non-linear and time variant effects in a rotor-bearing dynamic system. The non-linear characteristics of the rolling element bearing, internal damping, unsymmetrical stiffness of the shaft, cracks on the shaft, and the radial clearance are the typical root causes of these effects [1]. As rotating speeds increase and rotor weights decrease, these non-linear and time variant eff...

Single-phase squirrel cage and three-phase induction electromotors are the most popular electromotors used in industry from long ago. When an induction motor starts with direct connection method, it takes a lot of current from the power supply (several times the nominal current); so, several methods have been devised to start such electromotors. These methods either reduce the voltage of the st...

This paper presents a rotor position estimation technique for a 6/4 switched reluctance machine based on Adaptive Neuro fuzzy Inference System (ANFIS). This technique is applied for modelling the nonlinear rotor position of SRM using the magnetization characteristics of the machine. ANFIS has a strong nonlinear approximation ability which could be used for nonlinear modelling and its real time ...

In this paper, a fault tolerant control for induction motors based on backstepping strategy is designed. The proposed approach permits to compensate both the rotor resistance variations and the load torque disturbance. Moreover, to avoid the use of speed and flux sensors, a second order sliding mode observer is used to estimate the flux and the speed. The used observer converges in a finite tim...