Tamer M. Abdo

Using 2D finite element analysis in the calculation of current and force distributions for induction motors with broken bars

In this paper an ABC transient model of the three phase induction motor is developed that depends on self and mutual inductances calculation based on accurate finite element analysis (FEA). This model can represent both healthy and faulty motor conditions. The rotor broken bars faults are studied thoroughly including their effects on the rotor bar currents distribution, the forces exerted on the rotor bars, the motor speed and motor torque. It was observed that broken bar faults will cause fluctuations in the motor speed and torque. It was found that the non-uniform distribution of the rotor bar currents will lead to non-uniform radial forces affecting the bars. This will increase the mechanical stresses on the rotor shaft.

Regulation for wind generation system using ant system based Takagi Sugeno fuzzy PID

This paper introduces a new tuning technique for the PID control scheme that is adopted for regulating the magnitude and frequency of the wind energy conversion system (WECS) output voltage which presents interesting control demands and exhibits intrinsic non-linear characteristics. The developed technique is stem from blending the ant system optimization method with Takagi Sugeno fuzzy system approach. The optimum relationship between the PID controller gains and the parameters of fuzzy modules is explored using Ant system algorithm; hence a satisfactory dynamic performance of the WECS is obtained.

Performance analysis of coil-gun electromagnetic launcher using a finite element coupled model

In this paper the performance of a single stage capacitor driven coil gun electromagnetic launcher (EML) is investigated. The driving coil of the launcher creates a current pulse that depends on the capacitor charging circuitry specifics. The coil gun electromagnetic launcher system is analyzed using a mechanical model coupled to a magnetic finite element analysis model. The effects of changing the capacitor voltage level and the initial position of the projectile on the acceleration, speed and force are examined. The proposed analytical tool provides accurate calculations. The relations between the capacitor initial voltage, the initial projectile displacement and the final steady-state projectile velocity were examined. It was found that there is an optimum initial position for a projectile to achieve maximum launch velocity and this position depends on the projectile dimensions, mass and the value of the capacitor initial voltage.

Performance analysis of wound rotor induction motor subjected to rotor windings asymmetry

The aim of this paper is to analyze the performance of 3-phase wound rotor induction motor (WRIM) under rotor windings asymmetry. The behavior of WRIM were simulated under healthy and asymmetry conditions. With the aid of simulation results, variation of motor speed, electromagnetic torque, stator and rotor currents have been analyzed. To validate the simulation results a series of experiments were conducted for healthy and asymmetry rotor circuit. The results proved that for the asymmetry rotor windings conditions the stator and rotor current increase while the motor speed decrease and the ripples of speed and electromagnetic torque increase. The paper proved that the performance of the motor in the asymmetry rotor case is directly affected by the connection of rotor windings.

Analysis and force calculations for induction motors with broken bars using ABC frame model combined with 2D finite element method

In this paper, an ABC transient model of the three-phase induction motor is developed that depends on self and mutual inductance calculations based on accurate finite element analysis (FEA). This model can represent both healthy and faulty motor conditions. The rotor broken bars faults are studied thoroughly including their effects on the rotor bar currents distribution, the forces exerted on the rotor bars, the motor speed and motor torque. It was observed that broken bar faults will cause fluctuations in the motor speed and torque. It was found that the non-uniform distribution of the rotor bar currents will lead to non-uniform radial forces affecting the bars. This will increase the mechanical stresses on the rotor shaft.