<p>On the basis of analysis of dq model of permanent magnet synchronous motor (PMSM) and principle of field oriented control (FOC), detail modelling of PMSM drive system and simulation results presented in this paper. The PMSM model is based on electronic components rather than mathematical blocks, this enabled us to achieve simulation results more realistic.  Moreover all the modules of this simulation, such as inverter and pwm generator are made from scratch instead of using premade Simulink blocks.  Simulation was carried on the basis of step change in speed and torque then made performance comparison of several parameters such as abc current, dq current, speed and torque.</p>

Transverse flux permanent magnet (TFPM) machines are a potential candidate for directdrive wind power application due to high torque and power densities. The operating principle of TFPM machines is firstly described with various topologies available in literature, with the placement of magnets as a criterion for the classification of TFPM machine topologies. This review includes characteristics, power factor improvement, cogging torque minimization, material consideration, modelling techniques, and scalability. Different wind turbine concepts with direct-drive machines, control techniques and power converter topologies are also considered in this paper. INDEX Permanent magnet, topologies, transverse flux, and wind power.

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Abstract-With decreasing feature sizes, lowered supply voltages and increasing operating frequencies, the radiation tolerance of digital circuits is becoming an increasingly important problem. Many radiation hardening techniques have been presented in the literature for combinational as well as sequential logic. However, the radiation tolerance of clock generation circuitry has received scant attention to date. Recently, it has been shown that in the deep submicron regime, the clock network contributes significantly to the chip level Soft Error Rate (SER). The on-chip Phase Locked Loop (PLL) is particularly vulnerable to radiation strikes. In this paper, we present a radiation hardened PLL design. Each of the components of this design -the voltage controlled oscillator (VCO), the phase frequency detector (PFD) and the loop filter are designed in a radiation tolerant manner. Whenever possible, the circuit elements used in our PLL exploit the fact that if a gate is implemented using only PMOS (NMOS) transistors then a radiation particle strike can result only in a logic 0 to 1 (1 to 0) flip. By separating the PMOS and NMOS devices, and splitting the gate output into two signals, extreme high levels of radiation tolerance are obtained. Our PLL is tested for radiation immunity for critical charge values up to 250fC. Our results demonstrate that over a large number of radiation strikes on a number of sensitive nodes in our design, the worst case jitter is just 18%. In the worst case, our PLL returns to the locked state in 16 cycles of the VCO clock, after a radiation strike.

Abstract. Permanent magnet type motors (PMs) especially permanent magnet synchronous motor (PMSM) are expanding its limbs in industrial application system and widely used in various applications. The key features of this machine include high power and torque density, extending speed range, high efficiency, better dynamic performance and good flux-weakening capability. Nevertheless, high in cogging torque, which may cause noise and vibration, is one of the threat of the machine performance. Therefore, with the aid of 3-D finite element analysis (FEA) and simulation using JMAG Designer, this paper proposed new method for cogging torque reduction. Based on the simulation, methods of combining the skewing with radial pole pairing method and skewing with axial pole pairing method reduces the cogging torque effect up to 71.86% and 65.69% simultaneously. IntroductionFor the last decade, the demand of permanent magnet motors (PMs) with wide application prospect are receiving spotlight due to the advance development of high performance permanent magnet materials and manufacturing technology. In various PM motors, an interior-type permanent magnet motor (IPM) which magnet are inserted inside the rotor rather than bounding the surface shows better performances in flux weakening operation and achieve higher flux density due to the small air gap that allows to impose a magnetizing current effectively [1]. IPM motors are commonly used for industrial drives, electrical vehicle applications and generation systems as it has high element execution, and vitality change efficiency. However, due to PM air gap length, IPM create an extensive cogging torque issues.The cogging torque or also known as detent torque and 'no-current' is a famous issue, which happened in PM motors. The components of cogging torque are produce by the interaction PM and slotted iron structure, and shows itself by the propensity of a rotor to adjust in various stable positions even when a motor is not energized. This deteriorates the machine operation, performance of position control system, generating acoustic noises and vibrations, speed pulsations, harmonics distortion, and premature wear of the bearings during low speed [2]. The communications between PMs mounted on the rotor and anisotropy began by stator windings slots raised the cogging torque and variations of the magnetic field energy during the rotation, as indicated by [3]: