外文翻译--变频器使用浅谈.doc

The frequency converter is used and discussed lightly The asynchronous motor is such main power equipment of manufacturing enterprise as electricity , chemical industry ,etc.. As the high energy consumption equipment, its output power cant be up to the change pro rata of load, majority can only turn on through guard or valve degree regulate , but the energy that the motor consumes does not change much, thus cause very great energy to loss . In recent years, one that is with the maturity of the production technology of the frequency converter and range of application of frequency converter is extensive day by day, use the frequency converter to carry on technology to transform to the motor power into the energy-conserving , high-efficiency important means of every enterprise. Frequency conversion adjusts the speed principle n＝60 f(1－s)/p (1) In the type nRotational speed of the asynchronous motor; fFrequency of the asynchronous motor ; sThe motor is transfered to the difference rate ; pLogarithm very much of the motor。 Can know by type (1 ) rotational speed n in direct proportion to frequency f , only need change frequency f and change the rotational speed of the motor, motive power frequency realize that speed regulate. The frequency converter is mainly adopted and handed in- frank- hand over the side when frequency f changes in the range of 0-50Hz, the rotational speed of the motor regulates the range very widely. Frequency conversion transfer speed pass person who changes electricity , exchange frequently worker power change through the rectifier into a direct current source first just, then change the direct current source into the frequency , exchange power controllable in voltage in order to supply the motor. The frequency converter one there is generally from rectification circuit, in the middle of direct current link, go against not becoming and controlling parting of 4 pieces not to make up. Rectification part three-phase bridge controlled rectifier,