In this paper, a new approach is proposed to detect broken rotor bars in induction motors. The motor is disconnected from the supply, and the induced voltage in the stator due to only rotor flux is utilized to detect the fault. If there is any broken bar, it will directly affect the induced voltages in the stator windings. Using this approach, the effects of source nonidealities (such as unbalance, presence of time harmonics, etc.) and nonlinearity of machine magnetizing characteristics due to saturation can be avoided.

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In the BLDC motor-drive system, the leakage current from a motor to a ground network and existence of high-frequency components of the DC link current are the most important factors that cause conducting interference. The leakage currents of the motors, flow through common ground, will interfere with other equipment because of the high density of electrical and electronic systems in the spacecraft and aircrafts. Moreover, generally there are common DC buses in the mentioned systems, which aggravate the problem. Function of the electric motor causes appearance of the high-frequency components in the DC link current, which can interfere with other subsystems. In this paper, the analysis of electromagnetic noise and presentation of the proposed method based on the frequency spectrum of the DC link current and the leakage current from the motor to the ground network are done. The proposed method presents a new process based on the filtering method to overcome EMI. To cover the requirement analysis, the Maxwell software is used.

In this article, comprehensive analytical equations are developed to compute time-varying inductances of salient pole machines with any eccentricity type and degree in a unified technique. For this purpose, the inverse air-gap function of the eccentric salient pole machine has been defined, and its indefinite integral has then been determined. The derived analytical expressions, unlike the previous proposals, take into account all the harmonics of the inverse of the air-gap function without any development in Fourier series. The presented method eliminates the need for inexact analytical equations, numerical differentiations, and huge lookup tables, which are common in the modified winding function approach. Theoretical fundamentals and experimental results that validate the proposed technique are presented.

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In this paper, the control signal of the series-resonant converter is considered as a slope of a switching surface. The output characteristic of the converter, for an ideal case and above the resonant frequency, is achieved based on the slope of the switching surface. This output characteristic leads us to find the related slope for a specific converter gain. Nonlinear state equations of the series-resonant converter with new control input are represented in widely used class of hybrid systems that have been called piecewise affine systems. Considering the effects of the slope variations in the switching surface, a simple and efficient control law is achieved. The main advantage of the proposed method is the absence of microcontroller and frequency modulator integrated circuits in hardware implementation. This property makes the proposed method more beneficial in high-frequency applications. Experimental results confirm our theoretical investigations.