The Explioture And Study Of Intelligent AC Motor Energy-saving Starter

The reduce of energy loss and the starting quality of asynchronous electromotor is an important matter in the modern industry control. In the process of study about asynchronous electromotor, a blue print-energy-saving softstarter was put forward by peoples of scien and technology in order to reduce the wastage and realize smoothly starting. Although it can solve the aforementioned matter of asynchronous electromotor to a certain extent, it itself also has some limitation such as the low efficiency of energy saving and the vibrate of the controlling loop and so on. In this paper, a kind of intelligent energy-saving softstarter is introduced, which not only improve the energy saving effect but also avoid the vibrate of the controlling loop.In the paper, five jobs are done as following:Form the view of safety, the first part discusses influences of the voltage changing on stable running of a motor :1. analyzes a influence of the voltage changing on electromagnetic torque.2. studies the allowing scope of regulating voltages with changes of loads.3. probes into influences of the voltage changing on the power > efficiency and power factor. In the end, a conclusion is arrived at : when the dropping of loads makes performances of a motor bad, the means of reducing the armature voltage can improve performances of a motor and makes the motor economic runningThe second part makes use of theories and formulations of Television and Power Electronic Conversion Technology to calculate and testify the energy-saving theory of the intelligent energy-saving softstarter. Basing on general instances, the paper analyses changes of the power factor angle of a electromotor and the triggering angle of a thyristor by using a practical case. Results of calculating very accord with theoretic analyses, which illuminates that the intelligent energy-saving soft-starter has a better energy-saving effect.The third part analyses me working principle of me main circuit the triggering circuit ^ the protection circuit and the converting circuit of a intelligent energy-saving softstarter , specially traverses the triggering circuit, which realizes adaptive triggering by utilizing the adaptive principiumD梐utomatically regulating triggering pluses by surveying the change of load, load increasing , the triggering pluses is brought forward and the armature voltage is rising ; load decreasing ,the triggering pluses is lagged and the armature voltage is dropping; though the control of the armature voltage, improvement of capabilities of energy-saving and starting are realized.In the fourth part the performance and some using precautions are introduced , which mainly includes :1. technological performance characteristics 2. using directions 3. operation directions 4. protection directions.The fifth part of jobs is to present outcomes of electronic performance tests and protection performance tests of the intelligent energy-saving softstarter. Electronic performance testsInvolve: 1.starting characteristic experimentations 2.converting characteristic experimentations 3. tests of capabilities of turn-on ^ disjunction and over-loading 4.the highest energy-saving ratio experimentations; Protection performance tests includes : 1 .over-loading protection 2.1osting-phase protection 3.missing-voltage protection. According the results , the conclusion can arrived at that all properties and performances of the intelligent energy-saving softstarter completely reach the designing demand and are credible .