Experimental medium-power high-gain travelling-wave tubes of very short structure, with permanent-magnet focusing, for the 4 and 6 Gc/s bands

In this paper, a novel sensorless position control for a surface permanent magnet linear synchronous motor (SPMLSM) is presented. The position and speed of the SPMLSM drive is obtained through a closed loop observer by only measuring phase voltages and currents. Estimation of speed is done using difference between estimates of the current derivatives in the dq frame, which calculated two different ways: first using a high-gain observer, and then using the motor model. Estimation of the mover position is done through integrating the estimation of speed. The proposed scheme works in a closed loop fashion. It enhances the allowable initial position error; can be used without any physical modification; does not rely on motor saliency and requires no knowledge of the load. Results from numerical simulations and practical implementation are presented to validate the proposed schemes.

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Sensorless online measurements: application to variable speed drive systems

COMPEL The International Journal for Computation and Mathematics in Electrical and Electronic Engineering ◽

10.1108/compel-10-2016-0453 ◽

2018 ◽

Vol 37 (1) ◽

pp. 29-53

Author(s):

Ali Abdul Razzaq Al – Tahir

Keyword(s):

Permanent Magnet ◽

Control Design ◽

High Gain ◽

Synchronous Machine ◽

Design Approach ◽

Permanent Magnet Synchronous Machine ◽

Variable Speed ◽

Content Type ◽

Output State ◽

Online Measurements

Purpose Sensorless online measurements, application of variable speed drives has been given a great attention, especially over the past few years. In most of the previous literates dealing with permanent magnet synchronous motor (PMSM) drives, the combination of inter-sampled behavior with high gain design approach has not been discussed yet. This paper aims to discuss this feature in-depth. Design/methodology/approach The study contains a different approach for an observer running with surface-mounted permanent magnet synchronous machine drives to implement sensorless control. Design of sampled data observer methodology for one kind of AC machine having non-linear model and backed by an elegant formal stability convergence analysis using the tools of Lyapunov stability techniques was highly recommended in scientific contributions, and it is yet needed to be solved. Findings In this study, a solution to observation problem is covered and developed by combining ideas from the high-gain design approach and inter-sample predictor based on stator voltage measurements. The output state currents are accessible only at the sampling instant to solve the problem of states observation at continuous-time mode. This allows to reducing the usage of online appliances, improving reliability of control design and saving costs. Practical implications The proposed observer is capable of guaranteeing an acceptable closed loop dynamic response over a wide range of operation region and industrial process for random initial conditions. Originality/value The output state predictor has been interred in constructing the innovation correct term to prove the robustness of the proposed observer against attenuated sampling interval. To validate the theoretical results introduced by the main fundamental theorem and prove the observer stability convergence, the proposed observer is demonstrated through a sample study application to variable speed permanent magnet synchronous machine drive.

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High gain low reflectivity travelling wave semiconductor optical amplifiers integrated with passive waveguides operating at 1.3 μm wavelength

1993 (5th) International Conference on Indium Phosphide and Related Materials ◽

10.1109/iciprm.1993.380703 ◽

2002 ◽

Author(s):

T. Brenner ◽

R. Dall' Ara ◽

C. Holtmann ◽

P.A. Besse ◽

H. Melchior

Keyword(s):

Optical Amplifiers ◽

Semiconductor Optical Amplifiers ◽

High Gain ◽

Travelling Wave

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Dual Input Z-Source Inverter Fed PMSM Based Renewable Energy

Indonesian Journal of Electrical Engineering and Computer Science ◽

10.11591/ijeecs.v9.i2.pp257-261 ◽

2018 ◽

Vol 9 (2) ◽

pp. 257

Author(s):

V Karthikeyan

Keyword(s):

Permanent Magnet ◽

Permanent Magnet Synchronous Motor ◽

Direct Torque Control ◽

Power Production ◽

High Gain ◽

Synchronous Motor ◽

Torque Control ◽

Harmonic Content ◽

Bus Voltage ◽

Continuous Power

The proposed paper produces the high gain and low harmonic content in the permanent magnet synchronous motor fed Z-source inverter. The hybrid solar and fuel-based motor produces more power by using the direct torque control. The control based PMSM fed inverter for continuous power production. The dc bus voltage is regulated by using the DTC based PMSM. The speed of a permanent magnet synchronous motor is regulated, and the proposed DTC is minimizing the torque and flux ripple. In order to produce maximum power at the dc link and also improve the performance of PMSM in Matlab/ Simulink software.

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Unknown Disturbance Estimation for a PMSM with a Hybrid Sliding Mode Observer

Mathematical Problems in Engineering ◽

10.1155/2015/316360 ◽

2015 ◽

Vol 2015 ◽

pp. 1-7

Author(s):

Gang Chen ◽

Yong Zhou ◽

TingTing Gao ◽

Qicai Zhou

Keyword(s):

Permanent Magnet ◽

Digital Filter ◽

Sliding Mode ◽

Permanent Magnet Synchronous Motor ◽

High Gain ◽

Sliding Mode Observer ◽

Time Varying ◽

Disturbance Estimation ◽

Simulation Results ◽

Unknown Disturbance

A hybrid sliding mode observer that combines high gain feedback and a high-order sliding mode term is developed to identify the time-varying disturbance for a permanent-magnet synchronous motor (PMSM). Based on the measurable current and the position, the unknown disturbance can be identified from the sliding mode term without digital filter effect. It is then used to enhance the robustness of the speed control dynamics. For ease of implementation in real applications, such as DSP and FPGA, the proposed observer is properly designed to avoid complex mathematical operators. Simulation results are given to illustrate the performance of the proposed observer.

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