• Proceedings of the KIEE Conference
• /
• 1999.07a
• /
• pp.369-371
• /
• 1999

The post-arc current in VCB(Vacuum Circuit Breaker) was calculated from the transient recovery voltage. A differential equation for the post-arc current was derived from the equivalent circuit of the test circuit. And it's results were showed.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.38 no.1
• /
• pp.44-54
• /
• 2001

In this paper, a novel test method is proposed to detect the hard and soft fault in analog circuits. The proposed test method makes use of the offset voltage, which is one of the op-amps characteristics. During the test mode, CUT is modified to unit gain op-amps with feedback loop. When the input of the op-amp is grounded, a good circuit has a small offset voltage, but a faulty circuit has a large offset voltage. Faults in the op-amp which cause the offset voltage exceeding predefined range of tolerance can be detected. In the proposed method, no test vector is required to be applied. Therefore the test vector generation problem is eliminated and the test time and cost is reduced. In this note, the validity of the proposed test method has been verified through the example of the dual slope A/D converter. The HSPICE simulations results affirm that the presented method assures a high fault coverage.

• Transactions on Electrical and Electronic Materials
• /
• v.5 no.1
• /
• pp.19-23
• /
• 2004

A novel method of high speed, accurate circuit simulation in 3-dimensional (3-D) parallel-plate capacitors is investigated. The basic concept of the circuit simulation methods is partial element equivalent circuit model. The three test structures of 3-D parallel-plate capacitors are fabricated by using multi-layer low-temperature co-fired ceramic (LTCC) process and their S-parameters are measured between 50 MHz and 5 GHz. S-parameters are converted to Y-parameters, for comparing measured data with simulated data. The circuit model parameters of the each building block are optimized and extracted using HSPICE circuit simulator. This method is convenient and accurate so that circuit design applications can be easily manipulated.

• Journal of the Korean Society of Safety
• /
• v.22 no.6
• /
• pp.41-45
• /
• 2007

Short circuit and ground fault account for the primary causes of electrical fires. In this research, real-scale experiments were conducted to assess the possibility of electrical fires due to these causes. The experiment conditions were identical with an actual fire accident, in which the power cable was supported by an iron fence. The purposes of this research are to investigate the short circuit caused by wire cutting, the conductivity of the iron fence depending on its coating conditions, and the ground fault of one wire or two wires in an effort to reconstruct the fire accident. The test results show that, owing to the instant operation of circuit breaker in the moment of short circuit or ground fault, the generated ignition energy is far less than necessary to start an ignition. Therefore it is concluded that electrical fire is highly unlikely if the electric system is protected by a circuit breaker with normal functions.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2003.11a
• /
• pp.624-629
• /
• 2003

In this paper, broadband shunt technique for increasing transmission loss is experimentally investigated. Piezoelectric shunt damping is studied using resonant shunt circuit and negative capacitor shunt circuit. A resonant shunt circuit is implemented by using a resistor and inductor. Negative Capacitor shunt damping is similar in nature to resonant shunt damping techniques, as a single piezoelectric material is used to dampen multi-mode. Performance of both methods is experimentally studied for noise reduction. This is based upon SAE J1400 test method and a transmission loss measurement system is provided for it. This paper will present the test setup fer transmission loss measurement and the tuning procedure of shunt circuits. Finally the results of sound transmission tests will be shown.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2014.10a
• /
• pp.612-617
• /
• 2014

It is generally known that the automotive road wheel involves the non-proportional multiaxial loading condition, therefore the measuring dynamic stress and strain in driving state is very important to predict an endurance characteristic of the automotive road wheel. In this study, the ultimate driving test using F1 circuit with respect to 2 kinds of velocity conditions have been carried out in order to measure dynamic stress, strain of the wheel and acceleration of a vehicle. Based on the measured results, the characteristics of dynamic stress generation have been analyzed, and factors which have effect on the dynamic stress generation have been studied.

• Transactions on Electrical and Electronic Materials
• /
• v.10 no.1
• /
• pp.9-15
• /
• 2009

There is a growing demand for a high voltage silicone rubber composite with high mechanical property and high electrical property. The effect of modified cross-linking agent on the mechanical, electrical properties, and short-circuit test performance of silicone rubber insulators have been investigated. To use base polymer, the various silicone polymers were prepared by the equilibrium polymerization. Aluminum trihydrate surface was treated by vinyl silane. Liquid silicone rubber nanocomposite was prepared from the compounding of VPMPS, HPDMS, catalyst, and alumina trihydrate modified with 1,3,5-trivinyl-l,3,5-trimethylcyclotrisiloxane. The mechanical property and electrical property for insulation materials were measured, indicating the high tensile strength and the good short-circuit property.

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.24 no.3
• /
• pp.527-534
• /
• 1987

This paper proposes a new syndrome-testable design method for large MOSPLA's. In the conventional syndrome test method, the testing array circuit for testability is added but it has the defect that the circuit gives effect on the normal operation of the basic PLA circuit. Therefore, by adding the shift registers to the product lines of the basic MOSPLA's this defect is eliminated and the number of test patterns is decreased. In order to reduce the number of fault free syndromes to be predetermined, also, one output line, which is connected to all product lines is added. Therefore the number of output lines be observed is decreased. And the analytical method to compute fault free syndromes is presented. By unsing this method, the time and the effort to compute the syndromes are decreased.

• Journal of Applied Reliability
• /
• v.11 no.3
• /
• pp.245-249
• /
• 2011

Through the test of ESD(Electro Static Discharge) for PCB circuit, we are able to research on the ESD effect. This paper also studys on the ESD test method for measurement. In the measurement of the discharge current, we used current probe(TC-1). The applied voltage to the PCB metal is -3 kV HBM mode. In conclusion ESD influences exponentially greater impact in nearer PCB circuit.

• Proceedings of the KIEE Conference
• /
• 2007.07a
• /
• pp.913-914
• /
• 2007

Power transformer shall be designed and constructed to withstand the mechanical and thermal stresses produced by external short circuits which include three-phase, single line to ground, double line-to-ground, and line-to-line faults on any one set terminals at a time. This paper presents the method of short-circuit test and means of evaluation during and after each test to judge the results of short-circuit tests.