Application Study On On-Line Monitoring Technology Of Dielectric Loss Tangent For Capacitive Equipment Based On Wavelet Transform & Virtual Instrument

The on-line insulation monitoring of power apparatus is very important to guarantee the safety of power delivery, find insulation faults in time and increase the reliability of power supply. With the development of electrical engineering and the further demand on the service reliability of power systems, the on-line insulation monitoring has been put more value on. high voltage capacitive-type equipment plays a very important role in power systems, and dielectric loss tangent (tanδ) is an important parameter to reflect its insulation condition. Therefore, the study on the on-line tanδ monitoring of high voltage capacitive-type equipment has practical values.For the problem of dielectric loss tangent on-line measurement for capacitive type equipment, a virtual instrument based on wavelet transform and correlation technique is presented in this paper. By applying the construction of virtual instrument, the instrument has high level intelligence and satisfied character. The principle of the instrument is introduced in detail and the results are given. This paper great characteristic is to introduce wavelet transform to dielectric loss tangent on-line measurement for high-pressure capacitive-type equipment, thus the noise of signal is effectively restrained, and the accuracy tested has been improved. The greatest brilliant point of this paper is to structure the corresponding oniine detection system with the technology of virtual instrument. Because regard software as the core, itneedn't receive the restriction that the production firm designs the function like traditional instrument. Thus the uses can define the strong instrument function in a flexible way that utilized computer superstrong operation , show and expansion abilities.The paper includes six chapters. The mathematical analysis means which adopted at dielectric loss tangent on-line measurement are introduced. And the paper talks about the principle of wavelet transform. The development and characteristic of virtual instrument is summarized. And the demand of the system is analyzed. At last, simulation test are given. The result of the simulation test is satisfied.