Design, analysis and real time dynamic torque control of single‐rotor–single‐stator axial flux eddy current brake

This study presents design, analysis and real time dynamic torque control of a single-rotor and single-stator axial flux (AF) eddy current brake (ECB). Design of the AF-ECB is accomplished based on magnetic equivalent circuit (MEC) modelling. Influence of the key design parameters on braking torque including permeability and resistivity of the disc material is also investigated. Braking torque profile of the AF-ECB is obtained by MEC modelling and numerical analyses are carried out by three-dimensional (3D) finite element analysis (FEA) to validate the MEC modelling and to obtain the braking torque profile. 3D magneto-thermal FEA are also completed to identify working period at maximum braking torque. A prototype AF-ECB is manufactured based on the analyses, and open-loop torque profile is experimentally verified. Good agreement between the test, FEA and MEC results is achieved. A real time controller is developed and dynamic torque control of the brake for various torque and speed references is also obtained to illustrate the dynamic behaviours of the system

Modeling and Experimental Verification of an Unconventional 9-Phase Asymmetric Winding PM Motor Dedicated to Electric Traction Applications

Multi-phase permanent magnet motors are becoming popular in various applications such as high power traction which require low cogging and torque ripple, and reduced noise and vibration. This paper presents the development process of a full order detailed mathematical model for an unconventional nine-phase permanent magnet (PM) motor with asymmetric AC windings. The phase inductances are calculated based on the individual winding functions. Using these parameters, electrical equations for each phase based on the voltages and flux linkages are generated. These equations are transformed into an arbitrary reference frame and the torque equations are developed for the 9-phase motor. A Matlab-Simulink model is then developed for the proposed nine-phase PM motor based on the developed dynamic equations. Finally, the model is validated with the finite element analysis and laboratory testing of the prototype motor. It is shown that the developed mathematical model can be used for such complex asymmetric winding multi-phase PM motors

Current Statement of Intensive Care Units in Turkey: Data obtained from 67 Centers

OBJECTIVES: We aimed to obtain information about the characteristics of the ICUs in our country via a point prevalence study

Franchismo

We aimed to obtain information about the characteristics of the ICUs in our country via a point prevalence study