Control For Induction Motors Essay Example for Free

Control For Induction Motors Essay Project paln Soft starter and soft stopping for speed control for induction motors Introduction The project is entirely on the design and development of a soft starter converter that will satisfy and implement the soft starting and soft stopping for speed control of an induction motor. Soft starters also called solid state starter are used for gentle starting and stopping of induction motors. Pumps, centrifuges, compressors, escalators, belt conveyors, mills, fans, stone crusher and saws are typical applications. If a motor is not adequately protected the sudden change in rotation torque and speed, which occurs on starting and stopping will jolt the equipment linked to it. Over the long term this can lead to increase in mechanical wear of gearboxes, clutches, transmission and conveyor systems. Abrupt starting and stopping can also damage goods being handled by the mechanical equipment. For instance, the filling and distribution of glass bottles and containers loaded on to a conveyor holds a potential for a minor disaster. One sudden jerk during starting and stopping will surely cause the entire process line to engage in a mass of broken glasses and dripping liquids or sticky product. With pumps soft starters eliminate pressure shocks in pipes and valves when the pipe pump starts or stops. This poses a particular safety hazard when the transfer of volatile and/or inflammable liquid is involved. Background Information Soft starter controllers provide the soft starting and stopping of induction motors with no beyond high maximum currents, motor heating or mechanical shocks. However this is more vital for most of large machines because there is entirely reduced starting torque and reduced impacts on mechanical parts, however this result in an increase in the equipment lifespan. Also the soft starting and soft stopping result in mass energy saving the power supply since the starting currents and voltages are low, meaning the amount of power dissipated at the start is less as compared to a normal start without a soft start. An induction motor soft starting and soft stopping inverter is a vital aspect which serves as a premier protection to the machine itself and the entire production line. The outmost need for soft starting and soft stopping is to prescribe the inrush currents that an induction motor absorb when being started from rest. This needs attention because it eventually causes the line voltages to decline, which is nevertheless a danger to such loads sensitive to low voltages. These inrush cerrents and high starting voltages are major cause to mechanical stress; when large currents enters the motor windings a larger magnetic field is being produced which can cause some parts to attract and repel Objectives The main project aim is to design and develop a soft starter converter that implements the soft starting and soft stopping of an induction motor. Specifically, the project will focus on the following objectives 1. To design and develop the hardware components of the project that features the soft starting and soft stopping of an induction motor. 2. To design and develop the software hardware that could be integrated to the hardware 3. To demonstrate the converter responses to starting and stopping operations of an induction motor. Methodology Justification soft starter controllers ensure the soft starting and stopping of induction motors without excessive peak currents, motor heating or mechanical shocks.This has a particular importance in large machines due to the power consumption in the megawatt range. The energy adsorbed by the motor winding and the shock torque have both and important impact in the mechanical parts and consequently, influences the equipment lifetime. they allow the reduction of cable section and the energy peak power from the electricity supplier. An induction motor soft starting and soft stopping inverter is a vital aspect which serves as a premier protection to the motor lifespan and http://www.ctiautomation.net/Control-Techniques-Soft-Starters.htm https://docs.google.com/viewer?a=vq=cache:srtLMpIZcMoJ:www.eaton.com/ecm/idcplg%3FIdcService%3DGET_FILE%26dID%3D428122+soft+starter/stopping+induction+motorhl=engl=mypid=blsrcid=ADGEEShf7UdxSK-mMBvBj-zftdxPnL24HsZr2T32U2sCIlpx8wZ1tKtG_L3r51v4roi7xe-vF81v_Qmww-XYxvRGlNfR5yzJBmrupuoU0b35MJVZOBjH1byAnHUh2i8OyPBR8r9Cd-bJsig=AHIEtbS1MVgMGWzC7MHbsX548ilI1M0rEQ