| Along with developing modern city, increasing high building, the elevator is beginning to play a vital role for walking tool in everyday life, therefore the performance should be improved for both economy and efficiency. As far as the comfort sense concerned, the traditional motor uses the contactor to shift its operating state, and the double-speed asynchronous motor strings reactance together with resistance in the stator to alter its velocity modulation, which could not meet passenger's criterion. Moreover, the traditional control system is composed of the relay,contactor and control logic, which brings such defects as: excessive electrical parts, weak function, over- frequent electric failure, low reliability and short life etc. The programmable logic control (PLC) is designed specially for industry environment, which is being developed based on the requirement of sequential logic control. Herein, cause of its all merits, the elevator's relay control mode has been replaced by the PLC gradually. At the same time, as a result of the development of motor AC frequency inverter's technology, the elevator's driving mode has been replaced gradually by it from the original DC frequency control, which can not only meet the passenger's comfort criterion, guarantee steady precision, but also reduce the energy consumption, cut the operating cost. Therefore, the PLC control technology and the frequency inverter has been becoming the focus.This paper has explained: The PLC control, whose control system core is PLC, refers to be realized using PLC and its software for the elevator signal control; AC frequency inverter refers to be realized using AC transducer on the side of the motor's dragging control system. And the main content and assignments of this paper are: to establish overall frame of "PLC control exchange frequency conversion velocity modulation's elevator system"; to handle with the elevator's running mode together with some signals, which are such as security, inner-instruction, outer-call, hatchway, gate region, switch gate and limitation, using PLC; to make the elevator show its arrival floor, running direction and response of landing call, to realize its gate operator control; to realize the hoist machine's start, run, brake, stop, including counter rotating signal and multi-speed signal, using frequency inverter by PLC after operation ,judgments. The task is to finish the above tasks completely through the thorough fundamental research and the programming practice, and to realize its analog simulation.There are two core problems in this paper: One is the frequency inverter's parameter setup, to meet the criterion of its ride efficiency, comfort, landing accuracy and secure; another one is that elevator needs to be controlled by PLC signal control plus its software development. As far as the No.1 concerned, it can be dealt with by choosing appropriate frequency inverter, setting up reasonable parameter, designing and the programming. The option in this paper is frequency inverter of the VS -616G5, which is a universal one, and whose parameter setup is more complex than the specific one. As to the second one, which could be realized by... |
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