KMITL

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

Browse

Search Results

Now showing 1 - 9 of 9

Some of the metrics are blocked by your
consent settings
Development of a Rogowski Coil-Based Lightning Current Measuring System with Wide Frequency Bandwidth for Wind Turbines
(2026-01-01)
Pramualsingha, Sarawuth
;
Yamamoto, Kazuo
;
Yutthagowith, Peerawut
Accurate monitoring of lightning currents is critical for incident assessment and the implementation of protective measures in wind turbines. Owing to the complex geometry of turbines, direct measurement is impractical, making indirect approaches, such as the Rogowski coil, a promising alternative. The Rogowski coil provides galvanic isolation, fast transient response, and high current capacity; however, achieving broadband performance with a very low cut-off frequency remains a significant challenge. This article proposes a broadband Rogowski coil-based lightning current measuring system (RLMS) with an exceptionally low cut-off frequency. The system comprises a Rogowski coil, hybrid integrator, and digital filter. The coil was designed and optimized using transmission line theory and a distributed parameter model. The hybrid integrator, which combines the Sallen-Key and T-feedback topologies, ensures effective compensation, whereas the digital filter suppresses high-frequency noise. The feasibility of the RLMS was confirmed by a frequency response analysis in the frequency domain and time-domain comparison of lightning current waveform measurements against the reference system. The experimental results confirmed the effectiveness of the system for lightning current measurements. This demonstrates the strong potential for integration into wind turbines to enhance the accuracy of lightning detection and protection strategies.
Some of the metrics are blocked by your
consent settings
An improved Current Voltage Transferring Device for high current high frequency measurement
(2018-10-01)
Pattanadech, Norasage
;
Kando, Masaaki
This paper represents the characteristics of the improved Current Voltage Transferring Device (CVTD) for high current measurement including lightning impulse currents. The improved CVTD has been developed from the prototype CVTD to provide exceptional characteristics for high current with high frequency measurement. The improved CVTD in h-shaped configuration is made of copper and aluminium. The relationship between input current and output voltages of the new CVTD was investigated with short and long duration lightning impulse currents to establish the empirical formulas. The typical impulse current generator was used to generate 8/20 μs lightning impulse current with the amplitude of 940 A while the impulse generator with crowbar elements was utilized to generate 10/350 μs lightning impulse current with magnitude of 30.2 kA for the experiment. The lightning impulse current measurement characteristics of the CVTD and Rogowski coil were examined. From the experiments, the new improved CVTD shows the superior characteristics to measure the impulse currents with very fast rise time. Besides, nanosecond pulses superimposed on the lightning impulse currents were detected by only the improved CVTD. According to the experiments, there is no doubt that the new improved CVTD is a superior one for high current with high frequency measurement especially lightning impulse currents.
Some of the metrics are blocked by your
consent settings
Low voltage series arc fault detection using rogowski coil
(2018-08-13)
Sritrai, Eakburin
;
Kittiratsatcha, Supat
;
Polmai, Sompob
This paper presents series arc fault detection in low voltage ac circuit using Rogowski coil d/dt sensor. Series arc faults are simulated with various types of loads and current levels to understand the characteristic of arcing signal pattern and level. The Rogowski coil is designed to be able to detect high frequency di/dt component of the arc signal. The experimental results clearly show that by detecting the high frequency component of the di/dt, series arc fault condition can be reliably detected.
Some of the metrics are blocked by your
consent settings
Analyses of rogowski coils for partial discharge measurement
(2017-10-27)
Chonpathomphikunloed, W.
;
Paophan, B.
;
Kunakorn, A.
;
Yutthagowith, P.
;
Leelachindakrairerk, M.
This paper presents analyses of toroidal air core Rogowski coils (RCs) with self-integrator for partial discharge (PD) measurement. The RC is the electromagnetic transfer device for measuring fast current pulse. The RC has linear characteristic and no saturation due to the air core. There are four configurations of the RCs in the consideration in this paper. From each designed RC, inductance and turn of each RC was determined almost the same values but different configurations. To analyses of the developed RCs, those RCs were employed to measure partial discharge current with various artificial charge levels from 10 pC to 50 pC. Also, comparison of the PD signals measured by the developed RCs and low inductive shunt resistor was carried out. From the experimental results, the best developed RC has the highest sensitivity or lowest background noise. It composes of two copper winding wound in the different directions. The first winding is wound around the toroidal air core and the other winding is wound with the opposite direction of the first winding. The both winding are crossed at the inner of the toroidal core. This RC also has wind frequency bandwidth for PD detection. The developed RC is an attractive sensor in partial discharge measurement.
Some of the metrics are blocked by your
consent settings
Rogowski coil with a non-inverting integrator used for impulse current measurement in high-voltage tests
(2016-10-01)
Yutthagowith, Peerawut
This paper presents design and construction of an impulse current measuring system based on a Rogowski coil with a non-inverting integrator used for impulse current measurement in high-voltage tests. For convenience in current measurement in the high-voltage tests, the developed Rogowski coil is specifically designed as a clamp on device. For verification, the developed current measuring system was tested in comparison with a non-inductive shunt resistor and the same Rogowski coil with previous developed integrators. The various standard impulse currents, i.e. the steep impulse current (1/20 μs), the high impulse current (4/10 μs), the lightning impulse current (8/20 μs), the switching impulse current (30/80 μs), and the long-duration impulse currents with duration time of 1−3 ms were generated for comparative measurement in a high-voltage laboratory. From the experimental results, the developed Rogowski coil with the proposed non-inverting integrator has fairly high accuracy in wide frequency bandwidth covered the frequency bandwidth of the standard impulse currents in high-voltage tests. It can be concluded that the developed current measuring system has a promising characteristic being appropriate for measurement of impulse currents in high-voltage tests.
Some of the metrics are blocked by your
consent settings
New electrical shunt with two rectangular holes in a copper plate
(2015-11-01)
Kando, Masaaki
;
Pattanadech, Norasage
A new concept of an electrical shunt with two rectangular holes in a copper plate (ESRP) has been developed to be used for measuring a large current with a short-duration steep wave in a high-voltage field. The ratio of the input current to the output current is 10<sup>6</sup>, as obtained from a DC voltage test circuit. The electrical shunt has a special configuration. To verify the shunt current ratio of ESRP in a real application, the shunt current was connected to a sphere-to-sphere electrode breakdown test circuit with a 10 mm gap to measure the large damping current (8.4 kA) of a DC breakdown voltage. The voltage signal from the shunt was transmitted to excite two light-emitting diodes (max. 50 mA, 4 V), which were reverse-connected in series. The light-emitting diodes operated properly and were illuminated, which validated the capability of the newly designed electrical shunt.
Some of the metrics are blocked by your
consent settings
New current-voltage transferring device with different metals
(2015-09-01)
Kando, Masaaki
;
Pattanadech, Norasage
A new concept of an electrical shunt with different materials (aluminum and copper) has been developed to be used as an alternative current measurement device. The device provides better current measurement characteristics compared with the conventional current measurement devices such as a shunt resistor with an ammeter or the multiple shunts consisting of molybdenum having a low temperature coefficient and a Rogowski coil with an integrated circuit. The currents in several electrical circuits have been measured using the developed current-voltage transferring device (CVTD) as voltages between the aluminum and copper elements. The measured voltages (V<inf>m</inf>) are proportional to measuring currents (I<inf>m</inf>), which is shown as the following the experimental equation V<inf>m</inf> [mV] =kI<inf>m</inf> [A], in which k is a coefficient depending on the configuration of the CVTD.
Some of the metrics are blocked by your
consent settings
A rogowski coil with an active integrator for measurement of long duration impulse currents
(2014-12-03)
Yutthagowith, Peerawut
;
Leelachariyakul, Banyat
This paper presents design and construction of an impulse current measuring system based on a Rogowski coil with a non-inverting active integrator. The developed measuring system was designed for measurement of millisecond impulse currents. The comparative measurements of the same Rogowski coil with various integrators and of a non-inductive shunt resistor were carried out in an HV Laboratory. In this paper, the performance of the developed integrator with the same Rogowski coil was compared with that of other integrators (a conventional RC integrator, a compensated RC integrator and an inverting active integrator). From the experimental results, the proposed active integrator provides promising performance comparable to that of the non-inductive shunt resistor. This accomplishment will be useful in measurement of long duration impulse currents and also evaluation test of surge arrester.
Some of the metrics are blocked by your
consent settings
Rogowski coil with an active integrator for measurement of switching impulse current
(2013-09-02)
Limcharoen, Worrakan
;
Yutthagowith, Peerawut
This paper presents design and construction of an impulse current measuring system based on a Rogowski coil with various types of integrators, a conventional RC integrator, a compensated RC integrator, and an active integrator. The developed measuring systems were designed for measurement of switching impulse current waveform used in a residual voltage test of arresters. The comparative measurement of the Rogowski coil with those integrators and non-inductive shunt resistor were carried out in an HV Laboratory. From the experiment results measured by the same Rogowski coil with various integrators show that all current measuring systems provide accurate front time. The Rogowski coil with the conventional RC and compensated integrators provide inaccurate measurement of inverse current peak and tail time. The Rogowski coil with the active integrator provides all fairly accurate waveform parameters when it was compared to the measured results by the non-inductive shunt resistor. © 2013 IEEE.

KMITL

Browse

Filters

Settings

Sort By

Results per page

Search Results