KMITL

Permanent URI for this communityhttps://dspace.kmitl.ac.th/handle/123456789/1

Browse

Settings

Subject: search.filters.subject.PD measurement

Search Results

Now showing 1 - 2 of 2
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    The Bandwidth Verification of VHF Antenna and Apply for Partial Discharge Measurement
    (2022-01-01)
    Thungsook, Kittisak
    ;
    Pattanadech, Norasage
    ;
    Nimsanong, Phethai
    ;
    Srinangyam, Chissanupong
    This research explains the bandwidth verification and application of the VHF antenna for partial discharge measurement. Three different VHF antennas were used for the experiment. In the research, the measuring bandwidth of such antennas was evaluated using a network analyzer. The antenna properties such as return loss and voltage standing wave ratio were analyzed. Then, the partial discharge in the air was simulated using the surface discharge model. The physical phenomena of PD occur like pulse current transients and electromagnetic waves. The pulse current transients were detected using a coupling capacitor and HFCT sensor, while the electromagnetic wave was detected using a VHF antenna. five test positions of the VHF antenna were designated for partial discharge measurements namely 1, 2, 3, 4, and 5 meters away from the partial discharge source. The PRPD pattern, PD magnitude, and waveform obtained from the VHF antenna were compared with coupling capacitors and HFCT sensors and presented in this paper. It is found that the VHF antenna, which has higher return loss and lower voltage standing wave ratio, provides high performance to detect the electromagnetic wave of partial discharge.
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    Experience of a partial discharge problem of electrical cables in power plant
    (2018-07-02)
    Kongdang, P.
    ;
    Nganpitak, T.
    ;
    Sontayananon, N.
    ;
    Chamnong, C.
    ;
    Chuayin, C.
    This paper represents a Partial Discharge ("PD") problem occurred in 6.6 kV electrical cable systems in a power plant. During annual switch gear and cable termination box inspection, some parts of electrical cables were identified as burned. Using electromagnetic and PD theory, the burned electrical cables were caused by the touching and pressing of different phase cables with inadequate clearance space. The initial solutions were rearranging the cables, using heat shrink tube for jacketing to improve the cable insulation. Inspection window was installed for PD measurement with Transient earth voltage method. Periodical PD monitoring has been performed to follow up whether new cable rearrangement can reduce the problem. The core of this problem could be better and deeper understood by Root Cause Analysis (RCA). Extension of busbar, enlargement of the cable box for better arrangement and addition of environmental control was later applied with a satisfactory outcome.