Frequency Control System Design

With the continual development of power electronic technology,microelectronics, automatic control theory, computer technology andadvanced manufacturing technology, electric drive technology has alsoexperienced a historic revolution that AC speed control substituted DCspeed control and computer numerical control technique replaced analogcontrol technique. Alternating current converter has been widely used inmajor industrial countries since making its appearance from 1960s to 1980s.And it gradually became the perfect speeder gear for the technicaltransformation of enterprises and the updating of products. Frequency speedcontrol can be applied to majority situations of electric drive. For theaccurate speed control, it is convenient for controlling the positionvariation and variable speed running of mechanical drive. Frequency speedcontrol can significantly improve high efficiency of techniques and qualityof products due to the independence of speed change on mechanical part,and it also can save more energy than former constant speed running. Actingas an high and new-technology, supporting technology and energy-savingtechnique, frequency speed control has been extensively applied to fieldsof metallurgy, machinery, mine, oil, chemical engineering, water treatment,weaving, paper making, printing and dyeing, and household appliances,making great contribution to our national economy.The working unit author serving in is a research institute engaged inadvanced study and qualification tests of aero-engine, with many componenttest rigs of aero-engine. Among these test rigs, some are high-speedrotating equipments. The distinctiveness of test target requires higheraccuracy of speed control and speed stabilizing. Currently, these test rigsadjust their speed mainly relaying on frequency changer set, direct currentdynamo or complete aero-engine. Most of these devices were built in 1970sand 1080s, occupying broad area and not convenient for applying andservicing. They bear low accuracy of speed control and speed stabilizing,and consume high running cost, too. Along with the rapid development ofmachine manufacturing, automatic control engineering and computer technology, the research institute is processing the technologicaltransformation on some former test devices and adopting some advancedtechnologies to improve application field of tester and accuracy of testdata and to reduce test risk.This paper utilizes frequency speed control technology to initiallydesign the power of test rigs according to the requirement of high-speedtest rig of aero-engine components drafted by author's institute. Majorcontents include: operating principle of transducer, selection oftransducer and its control mode, whole control system design, fundamentalprinciple and solving program of electromagnetic compatibility (EMC),computer simulation of speed control system and so on. It is hoped thatthrough the design of this system, we can comprehend and grasp frequencyspeed control technology and some relevant technologies of control design,and make technical reserve for similar designs in future.