• Proceedings of the KIEE Conference
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• 2005.07b
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• pp.1038-1040
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• 2005

This paper describes the optimal design, construction and performance evaluation of voltage divider used in high power testing laboratory for voltage measuring system. These dividers, which are of R, C, R&C type voltage dividers, the voltage to be measured range from voltage to several ten kilovolts, the frequency of the signals has a bandwidth from DC to megaHertz Measuring transient voltage and currents in the high voltage power laboratory is generally accompanied by electromagnetic interface and induced noise. above all, the measuring capabilities of voltage measuring system are dependent upon short response time and it must be as free as possible of inductive effects. In this paper presents both characteristic of voltage divider and design of voltage measuring system.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.5
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• pp.502-507
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• 1999

An improved, accurate and reliable high-voltage measuring system utilizing a bushing-type capacitor is proposed in this study. This system measures voltages and phase angles of three-phase 22.9 kV power distribution lines and provides enough current to charge a battery for a motor-driven load switch and to operate the measuring and communication circuits for the distribution automation. For reliability, epoxy resin was used as the dielectric material of the bushing-type capacitor since the dielectric strength of epoxy resin is very stable over the wide range of temperature. Capacitances were investigated and found to be stable over the wide range of temperature and applied voltage, and the results indicate that the proposed measurement system is very reliable.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1571-1573
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• 1994

In order to substitute for the conventional measuring system which could bring about technical inconveiences, measuring techniques for the fast transient high voltage upto 100 kV and small signals less than 1 V are developed by use of Laser Source with Packets cell. for the former, capacitive voltage divider was specially designed for reducing the impulse voltage less than the half-wave voltage of pockets cell. For the tatter, interferometer type was employed as a mean to removing the fluctuation of Laser output intensity. And also the main beam through the Pockels cell and the reference beam from the Laser source are seperated before being detected respectively by photo diodes. And then, these two signals are amplified and compared for detecting only the small signals applied across the Pockels cell. Throughout this work, Laser-based measuring system is likely to enable us, at this moment, to detect correctly lightning impulse voltage upto 100 kV and the small signals less than 1 V upto the 2 MHz. Such a system could be employed as a possible diagnostic measuring system at the substation.

• Proceedings of the KIEE Conference
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• 1998.07b
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• pp.757-759
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• 1998

This paper proposes a new high-voltage measuring system that is able to provide current enough to charge a storage battery for a motor driving a load switch, and detect each phase voltage and phase angle in three phase distribution line accurately. In order to develop the reliable voltage measuring system we had designed and manufactured condenser-type bushing having good characteristics for temperature on account of using epoxy resin as dielectric material, and investigated the variation characteristics of capacitance via variation of applied voltage. The experiment results show that the proposed condenser has good characteristics to environmental changes.

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.566-568
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• 1993

A measuring technique for the fast transient high voltage is under development by use of laser source in order to substitute for the conventional measuring system which could bring about several technical inconveniences. At this moment, this work is aimed to construct a compact measuring system with the use of Pockels cell and specially designed voltage divider. This system is likely to enable us to measure the lightening impulse voltages at the level of 30kV, 50kV and 70kV. Throughout this work, qualified measuring devices are required to be developed for discriminating different kinds of noise from which the system should be protected.

• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1779-1781
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• 2003

For reliability of high voltage test results in test laboratory, traceability of measuring systems is to be needed. In this paper, it deals with traceability and uncertainty of AC voltage measuring system which is tested by comparison with reference divider.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.6
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• pp.699-703
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• 1999

It is known that the LDC(Line-Drop Compensator) becomes to lose the function of proper voltage regulation for its load currents due to the real and reactive power generated by DGS(Dispersed Generation System), when DGS is introduced into the power distribution system of which the voltage is controlled by LDC. Therefore, in that case, it is very difficult to regulate the distribution line voltage properly by using LDC. One possible solution for this problem is the real-time voltage regulation method which is to optimally regulate the sending-end voltage in real-time by collecting the real-time load data of each load data of each load section between measuring points and by calculating the optimal seding-end voltage value from them. For this, we must know the real-time load data of each load section. In this paper, a modeling method of representing a load section on high voltage line with DGSs as an equivalent lumped load is proposed for gaining the real-time load data. In addition a method of locating the measuring points is proposed. Then, these proposed methods are evaluated through computer simulations.

• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1674-1676
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• 2003

The factors affecting the accuracy of lightning current measuring system are figured out the materials and length of down-conductor, and impedance matching between grounding resistance and characteristic impedance of cable. The cable with the low characteristic impedance used to transfer the lightning current from the top of the tower is too long to measure the waveform of lightning current, exactly. Especially, the height of the tower can cause the change of front time and magnitude of lightning stroke current. Basically, in this experiment. It was found that the magnitude and rise time of the lightning current are extremely dependant in the length of down-conductor in lightning current measuring system.

• Proceedings of the KIEE Conference
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• 2002.07a
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• pp.348-350
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• 2002

In the high-power tests to be performed on electrical apparatus as switchgears, transformers, insulators, cable and so on the results of tests on these apparatus are extremely important to evaluate the performance of test object. The reliability of the results depends on the reliability of measuring systems used in the laboratories where tests are performed. This paper introduces factors of uncertainty and describes estimation of uncertainty in high-voltage measuring system used in high-power testing LAB. 1 in KERI.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.48 no.12
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• pp.777-784
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• 1999

Since the ultra-high voltage power apparatus are recommended to withstand switching surge generated from the electric power system, the switching impulse voltage is generally used to verify this requirement at the testing laboratories. Recently, the international standard(IEC 60060-2) related to the high voltage measurement techniques is revised requiring a traceability of measuring system for high voltage measurements. In this paper, a reference divider for switching impulse voltage is developed satisfying the revised. IEC standard and the possibility of applications has been investigated. Therefore, the characteristics of the high and low voltage side resistor and the shielding ring have been analyzed including the step response characteristics of the prototype divider. Throughout various efforts, it is confirmed that our measuring device has shown compatible characteristics as a reference divider.