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Item type:Publication, Design and Construction of Tesla Transformer for testing on Suspension Type Insulator Class 52-3(2024-01-01) - Some of the metrics are blocked by yourconsent settings
Item type:Publication, A System for PD Pulse Generating, Monitoring, and System Characterization(2024-01-01); 2 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Accurate Loss Tangent Determination in Damped Alternating Voltage Tests(2024-01-01); ; Paophan, BusayapolUnderground cables are crucial for sustainable energy systems due to their minimal visual impact, reliability, and resilience against weather-related disruptions. As reliance on renewable energy sources rises, their importance grows. Regular evaluation of these cables is essential for ensuring safety, reliability, and resilience of electricity networks. By promptly identifying risks like insulation degradation, utilities can optimize maintenance, prioritize repairs, and bolster the integration of renewables, enhancing overall infrastructure performance. Loss tangent is the most significant value used for evaluation of the cable condition. This paper presents an alternative method for estimation of loss tangent in comparison with a conventional approach in damped alternating current voltage (DACV) tests. In the loss tangent estimation, the equivalent circuit of the DACV test system and a damping factor of the measured test voltage are utilized in the loss tangent estimation. From simulation experimental results, it is found that the conventional method is not accurate in loss tangent estimation in cases of low loss tangent measurement in the range of 0.1% which is a typical value of the new and used underground power cables. However, the accuracy of the proposed method is still in the acceptable range for estimation of the loss tangent in the range of 0.1%1 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Effective design of a two-stage surge protective device for AC low voltage system protection(2024-01-01); - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Partial Discharge Measurement Based on an Inductive Mode Air-Core Sensor(2020-03-01); In this paper, an alternative technique for partial discharge (PD) measurement using an air-core sensor is proposed. The air-core sensor consists of an inductive mode air-core coil and the appropriate additional resistor. The approach for inductive mode enhancement of an air-core coil is presented. In the inductive mode operation, an output voltage which is proportional to an induced voltage from the air-core coil is utilized to determine PD currents and charges by a numerical integration. In the design process of the air-core sensor, parameter estimation with a computation algorithm is employed for extracting unknown circuit parameters of the air-core coil from a unit step response. These estimated parameters are crucial in an effective design of the PD measuring system. With the design circuit parameters, experiments in PD measurement were performed. From experimental results, the developed system has promising performance, and the sensitivity is in the range of a few picocoulombs. From this achievement, the proposed technique is a choice in PD measurement for high-voltage equipment in the laboratory and in the on-site measurement.1 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Frequency response characteristics of rogowskilightningcoil withmeasurementactive integrator for(2020-02-28); ; Yamamoto, KazuoThis paper presents frequency response characteristics of a Rogowski coil which is developed with an active integrator. Experiments are performed in a laboratory with a frequency function generator as a source. The frequency responses of the Rogowski coil and the integrator are recorded with both magnitude and phase in order to verify the capability in measur-ing lightning current waveshapes. For availability in lightning current measurement in the electrical sys-tem, the developed Rogowski coil is specifically de-signed as a clamp on device. The standard lightning current waveshape of the positive first stroke impulse (10/350 µs) is simulated to investigate the measur-ing system. It is found that the frequency bandwidth of the Rogowski coil with the integrator developed in this paper is proper in lightning current measure-ment. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Applications of a high frequency current transformer and air-core inductive devices for detecting a partial discharge location in a cable(2020-01-01); This paper presents applications of partial discharge sensing devices for detecting a partial discharge location in a cable. Three devices are under investigated. The first type is a high frequency current transformer (HFCT), while other two types are air core inductive devices with different configuration. The high frequency current transformer is constructed from a ferromagnetic material core, and the winding conductor is in a single compensation form. The first air core inductive device is wound in a single compensation pattern, and uses the return winding in the form of a copper sheet. The second air core inductive device, differently, is in a counter wound compensation pattern. In experiments, a partial discharge sensing device is installed at one end of the cable. The standard pulse calibrator is employed to inject partial discharge pulses at the designated locations along the cable. The Time Domain Reflectometry technique (TDR), which is based on the travelling wave theory, is employed in calculating the partial discharge locations. It is found that these three current transducers can detect the partial discharge pulses, and with the algorithm, which is developed using the Time Domain Reflectometry, the partial discharge location along the cable can be identified accurately. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Study of a partial discharge location technique for power cables using high frequency current transducer(2018-11-01); ; Pumyoy, SuparatIn this paper, a partial discharge location technique for power cables was studied. PD signals are measured by high frequency current transducer which has been experimentally verified and installed at the end one (near end) of cable. The standard PD pulse calibrator with the charge of 200 pC was used to investigate the PD location at various position along the cable with total length is 37.925 m. The PD location method, time domain reflectometry (TDR) is used to locate the PD defect along the cable, which essentially based on the f travelling wave theory. From the experimental results of PD location, the highest error of PD location by time domain reflectometry method is 0.859 % at PD defect point (x) of 21.41 m. From this experiment, the proposed technique can be applied to further practical application and research related to PD location. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, The performance of a high frequency current transducer for partial discharge measurement under testing with a power frequency converter(2018-11-01); ; In this paper, the performance of a high-frequency current transducer (HFCT) for partial discharge measurement under testing with a power frequency converter is presented. The performances of the HFCT in comparison with the conventional partial discharge detection system (Omicron MPD600) were investigated terms of the ability to classify partial discharges and the background noises in the system from PD test cells in case of corona discharge, internal discharge and surface discharge. It's found that the presented system provides the better performances (in terms of the background noise) than conventional PD detection system and it can also be used to distinguish type of partial discharges. In addition, the presented system has been used for the real partial test on the PD test cells successfully. The HFCT for PD detection is an attractive choice in the PD tests of high-voltage equipment.