The Research Of Intelligentized Full Digital Low-Voltage Filter Compensation Device

Along with the development of modern industry technology and the mass application of kinds of nonlinear and time variability electronic devices such as inverters, rectifiers and various switching power supply, harmonic pollutions in the power system are becoming increasingly serious. These harmonics overlapping in public supply network will cause serious distortion of the exchange network voltage and the current waveform, and bring serious harms to kinds of power equipment and communication line of the public supply network. The decline in the quality of the power grid has a serious impact on safe economic operation of supply and demand of electrical equipment and reduces people's quality of life. Therefore, the harmonic management has already become an urgent problem in electrical engineering field.Firstly, the formation, enlargement and harm of power grid harmonic are analyzed in this paper. Related investigations on all types of harmonic sources are done. And the specific technical requirements of the international and national harmonic standards are introducedSecondly, two types of compensation devices of active filter and passive filter are introduced and their advantages and disadvantages are analyzed. In China's current conditions, the passive filter device is an acceptable and promising device.On the basis of a large number of documents of foreign and domestic passive filter compensation technology, the existing problems of these low- Voltage filter compensation device are analyzed. Through rational method, a new filter compensation controller adopting optimal control model is developed and a hardware design scheme of filter compensation controller based on the structure of dual-CPU is given. The reactive power compensation adjuster is introduced which could fleetly switch and control the filtering compensation slip. The SCR trigger drive circuit is introduced which could work with the control orders of the controller to achieve rapid, accurate filter compensation. It is proved by the running test that the operation of Intelligentized Full Digital Low-Voltage Filter Compensation Device can effectively restrain harmonic distortion, eliminate power grid pollution , improve power factor, guarantee normal operation of the production equipment, and make the power supply quality meet the national standards.