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Presently, induction motor adjustable speed drives are being popular in the industrial applications replacing existing techniques such as Direct Current (DC) motors and Silicon Controlled Rectifier (SCR) bridges. In this paper, the induction motor's stator inter-turn fault has been diagnosed by advanced Digital Signal Processing (DSP) technique. The Wavelet Transform (WT) algorithm is applied for stator winding fault diagnosis purpose in the transitory period. The wavelet transform's approximation signal is chosen for stator inter-turn fault diagnosis purpose for variable load effectively. The obtained results by WT technique demonstrated that the early fault detection is possible and it is prevented before the machine reaches the disastrous conditions. Therefore, millions of dollars may be saved for industries during unexpected shutdown. [ABSTRACT FROM AUTHOR]

Induction motors are the one of the most important production machines of any industry around the world. Therefore, the condition monitoring of induction motors is very important for successful and profitable running of an industry. Broken rotor bars are one of the critical health problems of any induction motor. To tackle this, application of Stockwell-Transform (ST) is presented in this paper. ST has been applied on the simulated signal of rotor broken bar and the results are compared with the Fast Fourier Transform method, which is a frequency domain analysis method. Normally, frequency domain analysis fails to detect the broken bar of the rotor if the severity of damage is low. The results obtained by applying ST confirms that the ST transform is able to detect the breakage of rotor bar better if the damage level is small. [ABSTRACT FROM AUTHOR]

Nowadays, permanent magnet machines are being popular in the industries due to its higher efficiency compared to conventional electric motors. This paper presents the modeling and simulation of three and five phase permanent magnet synchronous motor machine for healthy as well as open phase fault condition. In this paper, the crucial performance of the system has been analyzed before failure and after failure. The after effect of failures might result in costly damage and lead to another fault, if nothing is planned earlier for this fault protection. This undesirable situation ought to be averted, or at least there may be a fault tolerant function to deal with such failures. Therefore, a control scheme under an open or multiple phase fault has been discussed in this paper for multi-phase PMSM drive with sinusoidal back EMFs. In the three phase system, one phase has been kept open, whereas for five phase system, two phases kept open one by one for analysis purpose. The fault has been created only for some instant of time, after occurring fault, the PI controller compensated phase faults. Finally, it has been observed that the multi-phase machines have higher fault tolerant capability. [ABSTRACT FROM AUTHOR]

In the present time, the multilevel inverters gained a large interest by the researchers due to proficient power conversion with multiple voltage steps and consequently improved power quality, higher electromagnetic compatibility, reduced switching losses, and better voltage capability. Generally, the multilevel inverters are widely used in the industries for high power and high voltage applications. The multilevel inverter topology synthesizes a sinusoidal voltage from several levels of voltages obtained from capacitor voltage sources. This paper presents a three phase five level diode clamped inverter fed induction motor drive. The simulation of the model has been done in the latest Matlab/Simulink environment. The proposed simulation model gives efficient results with reduced harmonics in the stator current of the motor. Further, the harmonic analysis of the inverter voltages has also been done. Furthermore, for reduction of significant harmonics, active filter has also been used. This proposed simulation model may be used in many power electronics and drive applications. [ABSTRACT FROM AUTHOR]

These days, the induction motor driven by inverter, drives are being popular and used in the industries for variable speed applications with very competitive pricing. In this paper, a new dynamic pulse width modulated inverter fed squirrel cage induction motor simulation model is used for the stator inter-turn winding fault detection purpose. Through the proposed model, the transient behavior of the induction motor has been analyzed for healthy as well as for stator interturn faulty conditions by time domain approach. Therefore, early, stator inter-turn fault diagnosis is possible and may avoid the motor to reach in the catastrophic conditions. Therefore, may save large revenues for industries. [ABSTRACT FROM AUTHOR]

Bearings are one of the critical components in rotating machines and the majority of failure arises from the defective bearings. Bearing failure leads to failure of a machine and unpredicted productivity loss for production facilities. Hence, bearing fault detection and diagnosis is an integral part of the preventive maintenance procedures. In this paper, vibration signals for four conditions of a deep groove ball bearing Normal (N), fault on Inner Race (IR), fault on ball and fault on Outer Race (OR) were acquired from a customized bearing test rig, under no load and full load condition and each load condition with two fault size 0.007 inch and 0.021 inch has been taken. Statistical parameter from the time domain has been used as a feature of vibration signal for the classification purpose. Sensitivity analysis is performed to understand the significance of each input feature on the ANN (Artificial Neural Network) output. The ANN performance has been found to be comparatively higher to those feature which are highly sensitive. [ABSTRACT FROM AUTHOR]

This paper traces the basic concepts behind the predictive control strategy used in power converters and drives. Wide research on predictive control has been increasing day-by-day. With the availability of new digital control techniques, various schemes has been proposed. Predictive control scheme presents several advantages over other control schemes that makes it capable for various applications in the field of power electronics and drives i.e. inclusion of constraints and nonlinearities. A classification of predictive control scheme is presented and each scheme is described along with its application. This paper reflects the robustness as well as flexibility of predictive control scheme. Predictive control scheme has the capability to advance the performance of future energy processing and control systems. Keywords: Deadbeat Control, Model Predictive Control, Power Electronics, Predictive Control. [ABSTRACT FROM AUTHOR]

Nowadays, the Squirrel Cage Induction Motor(SCIM) fed with PWM (Pulse Width Modulated) inverter is being extensively used in the industries to achieve variable speed for many applications. It provides greater advantages on cost and energy efficiency for varying speed applications as compared to other available industrial solutions. These kinds of drives are recently gathering enormous interest in the multi-megawatt industrial drive applications. In this paper, the bearing fault of the SCIM has been diagnosed in the transient condition as well as steady state conditions by advanced Digital Signal Processing(DSP) transformative techniques. The bearing fault has been diagnosed in the steady state condition by Fast Fourier Transform (FFT) algorithm and in the transient condition by time domain as well as wavelet transform. The results obtained by all three transformative techniques has been compared and it has been concluded that the wavelet transform is most suitable technique for early fault detection purpose. As a result, an early diagnosis of bearing fault is possible by wavelet transform and damage can be averted. Thus, industries can save money using this approach. [ABSTRACT FROM AUTHOR]

The Pulse Width Modulation (PWM) inverter fed Induction (IM) is widely used in the variable speed drives applications these days with more efficient performance. In the present time, the developments in power electronics and semiconductor technology have led to prevalent use of power electronic converters in the electric drive systems. Many PWM techniques are being used to obtain variable voltage and frequency supply from a three-phase voltage source inverter. The sinusoidal PWM technique has been widely accepted by the researchers, academicians and in the industries. But in the present time, space vector PWM (SVPWM) trend is increasing because of their easy digital realization, low switching losses, reduced harmonics with better dc bus utilization. The main advantage of SVPWM is that it reduces harmonic content in the line to line voltage and increases fundamental output voltage by approximately 15% with smooth control of induction motor. In the present paper, the authors have proposed and developed open and closed loop SVPWM inverter fed Induction motor model in the latest MATLAB/Simulink environment. It has also been observed that the closed loop model gives better results as compared to open loop model. Further, the V/f control and Total Harmonic Distortion (THD) analysis has been carried out. [ABSTRACT FROM AUTHOR]

Induction Motor (IM) with electronic inverters presents greater advantages on cost and energy efficiency as compared with other industrial solutions for varying speed applications. These inverter fed-motors are recently gathering great recognition for Multi-Megawatt industrial drive applications. In this paper, a dynamic simulation model of PWM inverter fed IM has been presented and analyzed. The model has been developed in the recent MATLAB/Simulink environment to analyze the transient behaviour of IM in healthy and faulty condition of bearing. The dynamic simulation of IM is one of the key steps in the validation of the design process of the motor-drive system. It is extremely needed with the priority for eliminating the probable faults beforehand due to inadvertent design mistakes and changes during the operation. The model gives encouraging results with reduced harmonics[1]. In the present work, a successful diagnosis of bearing faults of an IM in transient condition has been carried out. Therefore, an early detection of bearing fault is possible by this model and may avoid the motor to reach in the catastrophic conditions. Consequently, this technique may save millions of dollars for industries. Further, the time domain analysis has been carried out for bearing fault detection purpose. [ABSTRACT FROM AUTHOR]