ANALYSIS OF THE OPERATING MODES OF THE SUSPENDED CABLE CAR ELECTRIC DRIVE USING THE VECTOR CONTROL SYSTEM

Continuous transport systems, including rope conveyors designed to move people and goods, are subject to very strict safety and energy efficiency requirements. As a rule, suspended cableways in operation have an unregulated electric drive with a smooth start system. Among the ways to meet these requirements is the use of modern regulated electric drives. The electromechanical system with a vector-controlled asynchronous electric motor is considered in the work. Based on the obtained model, within the framework of the MATLAB / Simulink application package, an investigation of the dynamic characteristics of the cableway electric drive was carried out. An analysis of the nature of the distribution of dynamic error in terms of speed and energy losses depending on the load and speed of movement of the rope traction element of the transport system is given. The results presented in the article make it possible to choose rational electric drives for continuous transport systems with rope traction elements. References 5, figures 5, table.

The Potential of DAS on Underwater Fiber Optic Cables for Deep-Sea Current Monitoring

<p><span>Distributed Acoustic Sensing (DAS) </span>enables<span> the </span>use of <span>existing </span>underwater <span>telecommunication </span>cables <span>as multi-sensor arrays</span>, allowing for detailed<span> study of the seismic wavefield. </span>Since <span>underwater </span>telecommunication <span>cables </span>were not deployed for seismological investigations, <span>the coupling between the </span>cable and the seafloor varies<span>, dramatically reducing the usefulness of </span>poorly coupled<span> cable segments</span> for<span> seismological research. In particular, underwater cables include segments that are suspended </span>in the water column across seafloor valleys or other bathymetry irregularities. Here, we propose that <span>ocean bottom currents may be studied by monitor</span>ing the vibrations of suspended cable <span>segments</span>. We analyze <span>DAS-strain recordings</span> on <span>three dark fibers deployed in the Mediterranean </span>S<span>ea. </span>Several cable segments, presumably suspended, feature h<span>igh-amplitude signals with harmonic spectra</span> as expected from<span> a </span>theoretical <span>model of in-plane vibration of hanging cables. The spatial shape of the vibration modes are determined by filtering and stacking. Their comparison to theory allows constraining the attenuation of longitudinal waves propagating along the cable in the non-suspended sections. The vibration frequencies change over time scales of tens of minutes. </span>Assuming that<span> oscillations of </span>suspended<span> sections are driven by deep sea currents, the temporal fluctuations of the vibration frequencies</span> <span>are related to changes of the cable</span>s<span> tension which, in turn, are related to the drag force induced on the suspended cable by </span><span>the shedding of </span><span>Karman </span><span>vortex</span>.<span> On this basis, we propose a method to infer changes of deep sea current speeds from the changes of fundamental frequency of cable vibrations</span>. Submarine optical reconnaissance campaigns and controlled smaller-scale experiments are planned to validate the approach. <span>The work aims at </span>demonstrating the potential of using suspended telecommunication <span>cable</span>s<span> to </span>monitor and investigate <span>marine currents in </span>deep <span>ocean environments. </span></p>