Multi-SPEED resolvers are desirable position sensors for high performance closed-loop control of inverter driven machines due to their high accuracy. However, developing a winding with high number of poles with limited number of slots is a main challenge in achieving multi-SPEED function. Therefore, in this paper different winding configuration are proposed to achieve 5-X performance of a disk type wound-ROTOR resolver. Then, the best winding is chosen for experimental verification. In addition to the accuracy of the sensor, the optimal winding selection index is defined considering copper usage, number of winding layers (overlapping or non-overlapping configurations), the number of turns for each coil of the winding (variable or constant turn configurations), and the amplitude of the fundamental harmonic. An objective function is defined involving all the mentioned indices with different weights determined based on the importance of each index. Finally, a prototype of the sensor with the best winding is built and tested. The experimental measurements verify the results of the simulations that are obtained using 3-D time setting finite element analysis.

Single-phase motors are among the most widely-used motors in low-power applications. These motors are omnipresent in residential applications and make up a majority of this sector. Previously these motors were specifically employed in constant velocities. Over time the need for SPEED control in these motors has brought this problem into focus of many research investigations. Sensorless control of single-phase motors is particularly appealing due to mechanical and economic considerations. In the present paper, one attempts to control motor SPEED by influencing ROTOR flux orientation through a vector control method and propose a new method of SPEED estimation based on extended Kalman filter algorithm. In order to estimate single-phase induction motor SPEED together with on-line ROTOR resistance estimation, the measurement noises have been accounted in EKF algorithm. The proposed method is validated with a simulation that includes ROTOR resistance changes and measurement noise.

The ROTOR of Enegelberg whitener was equipped with a screw conveyor to reduce broken rice percentage. According to preliminary experiments this modification could reduce broken rice percentage about 2.5%. Further experiment was performed to determine the effect of ROTOR SPEEDs and blade positions on white rice quality. To do this, five ROTOR SPEEDs, consisting 500, 600, 700, 800 and 900 r.p.m and three blade positions including, distance blade from entrance side of ROTOR was 7mm and from exit side was 9mm, distance blade from entrance side and exit side was 8mm equally, finally distance blade from entrance side of ROTOR was 9mm and from exit side was 7mm were examined using a experiment factorial randomized complete block design. The considered white rice quality measures were percentage of whole rice, broken rice, degree of milling and performance index. According to the result, ROTOR SPEED had significant effect on whole white rice and broken rice in level of 5%. Blade position and the interaction of ROTOR SPEED and blade position had significant effect on degree of milling and performance index at level of 1% and 5% respectively. Based on the results, the optimum operating conditions were 600 r.p.m and  distance blade from entrance side of ROTOR was 9mm and from exit side was 7mm. The ROTOR SPEED of 800r.p.m leads to same result.

Investigation of spike stall formation and its propagation in a low-SPEED axial-flow compressor is the main aim of this study. Experimental measurements are performed in a low SPEED axial compressor test rig. Measurement parameters include instantaneous velocity and static pressure at the stall inception process. For this purpose several hot wire probes and a high response pressure transducer are used in data acquisition procedure. Instantaneous fluctuations of velocity at upstream of the blade row show that spike stall inception is accompanied by flow separation from the leading edge of the ROTOR blade and subsequently, formation of a vortex. This vortical structure extends over the blade span. Stall cell propagates with a circumferential SPEED lower than ROTOR wheel SPEED which is equal to 66% of rotational SPEED in this compressor. Furthermore, wavelet frequency analysis is employed for detailed investigation of spike disturbances and the capability of this method in distinguishing the spike stall is presented. Wavelet analysis, by representing the temporal variation of frequency spectrum, shows dominant phenomena in the transient process from stable operation to the stall inception condition.

Coreless axial flux permanent magnet (PM) machines (AFPM) have attracted significant interest over the last decades as an ideal candidate for a wide range of applications. This is generally due to their advantages, such as the high torque density, high power density, and the light weight. This paper investigates the performance of a coreless axial flux-switching generator (AFSMG) with improved torque characteristics. The inherent feature of the axial flux-switching machines is the high cogging torque. Hence the main advantage and the novelty of this research is addressing a suitable key for its torque characteristics challenges. In this regard, a comprehensive study is done on ROTOR tooth shape. First, the geometry and the shape of the ROTOR tooth are optimized, and then the skewing technique is applied to minimize the cogging torque and improve the total harmonic distortion. Finally, the cogging torque and the THD are calculated in the primary design and the optimal design. The Taguchi method is utilized to improve the primary model. A comparative analysis of the primary and optimized model is carried out, which indicates the better performance of the optimized design. Furthermore, the 3D finite element method is applied to verify the results of the presented model.

Most of the methods that have been proposed for SPEED estimation of induction machines require the ROTOR and the Stator resistance to change in the normal operating range. On the other hand, estimation of the ROTOR resistance requires ROTOR SPEED. In this paper, after studying conditions for simultaneous estimation of ROTOR SPEED and ROTOR resistance, a method for simultaneous estimation of ROTOR SPEED, ROTOR resistance and stator resistance is proposed. In this method, an additional frequency component is injected to the reference flux and Fast Fourier Transform is used to estimate ROTOR SPEED and ROTOR resistance. Stator resistance is estimated from estimated stator flux using a fuzzy estimator. Finally, effectiveness of the sensorless SPEED controlled induction machine drive with simultaneous ROTOR and stator resistance estimation has been verified with simulation results under various operating conditions, especially at low SPEED and generating conditions.

In this paper, the authors present a novel approach to design a high-SPEED permanent magnet synchronous generator (HS-PMSG) with a retention sleeve. The importance of the retention sleeve becomes conspicuous when the ROTOR suffers from the radial and tangential stresses derived from a high SPEED say 60 krpm. With respect to the mechanical property of Titanium, this material has been demonstrated that it could be a proper material for the retention sleeve. The investigations of this paper are concentrated on the electromagnetic coupled with mechanical design of a 2-poles, 18-slots, 40 KW HS-PMSG which is carried out through FEM analysis using JMAG 17.1 and ABAQUS CAE and optimized through the well-known Taguchi optimization method. The obtained results assure the robust mechanical behaviour of the HS-PMSG at a rotational SPEED of about 60 krpm meanwhile the cogging torque, the Joule loss, and the total weight of the optimally designed HS-PMSG are reduced 44.71%, 27.87%, and 2.78%, respectively compared with the initial design.