Analysis of the influence of drydock main pumps drive on electric network
Journal Title: Восточно-Европейский журнал передовых технологий - Year 2019, Vol 5, Issue 8
Abstract
<p>The influence of unadjustable-speed AC drive and adjustable-speed DC drive of the drydock main pumps on the network of the Okean shipyard (Ukraine) is investigated in MatLab SimPowerSystems.</p><p>To accurately simulate deep-bar induction motors, the own method of determining the parameters of the T-shaped equivalent circuit and viscous friction coefficient of a virtual motor according to catalog data is used. This method is based on formulas that correspond to the T-shaped and refined L-shaped equivalent circuit. It is proposed to introduce the corrected values of the initial starting and critical torque ratio into the calculation. The rated power factor is determined indirectly and compared with the catalog value. The dependences of rotor resistance are approximated by elementary functions, which provide almost constant values of these parameters at subcritical slip values.</p><p>As a result of the simulation, it became clear that even with the alternate starting of unregulated electric pump units, there is a significant voltage drop in the network.</p><p>The mathematical model of DC drives was built with a common dual-circuit automatic speed control system. A resonance filter is included at the input of each synchronized 6-pulse generator, thereby eliminating possible errors in operation.</p><p>The simulation results prove that during the operation of DC drives, there are switching voltage variations in the network, substantially non-sinusoidal current consumption and reactive power consumption. Given the stray capacitance of the cable line, high-frequency voltage fluctuations occur, which are dangerous for electric equipment.</p>Through the use of the harmonic filtering and reactive power control device, these negative phenomena can be eliminated, thus, the DC drive will surpass unadjustable-speed induction motor drive in many respects. To minimize reactive power consumption, an automatic control system with an integrated variable gain reactor power controller can be used
Authors and Affiliations
Pavel Khristo
Investigation of the combination of ITO/CdS/CdTe/Cu/Au solar cells in microassembly for electrical supply of field cables
<p>Studies aimed at optimizing the design of micromodules based on ITO/CdS/CdTe/Cu/Au photoelectric converters, which are used in autonomous power plants for field camps, have been carried out. To use photoelectric conve...
Development of a method for optimizing operation of centrifugal gas superchargers under conditions of uncertainty
<p>A problem of development of a method of optimal control of operation of natural gas superchargers by a criterion which both minimizes fuel gas consumption and takes into account power of nitrogen oxide emissions into...
Elucidation of the mechanism that forms breadbaking properties of the spelt grain
<p class="a">The technology of making dough from spelt flour differs from that known for flour of soft wheat in which starch grains are firmly bound to the protein matrix. It has been established that the content of prot...
Development of procedures for determining the parameters of an aircraft servo actuator
<span lang="EN-US">Main trends in the use of electro-hydraulic actuators and requirements to parameters were discussed. Necessity of using automatic methods for testing an electro-hydraulic actuator together with the sta...
Synthesis of magnetite nanoparticles stabilized by polyvinylpyrrolidone and analysis of their absorption bands
<p>We report results of studying the synthesis of magnetite nanoparticles. The formed dispersions were explored with the use of the spectrophotometric method. The spectra of optical absorption of nanomagnetite dispersion...