• 전기의세계
• /
• v.42 no.7
• /
• pp.45-55
• /
• 1993

다른 차단기보다 성능이 우수하고 수명이 길며 보수점검이 용이하고 소형 경량화가 가능한 VCB의 이론을 차단원리, 구조와 기능, 소호원리, 개폐서지현상등으로 나누어 원리를 설명하였다. 또 VCB가 각 분야의 전력설비에의 차단기로서 적합함을 기술적으로 검토하였으며, 장래에 대한 전망과 우리나라의 기술수준을 밝히므로서, VCB 생산업체에서는 기술제고 노력을 촉구하였으며, 산업계에서 새로 건설하거나 기존 설비를 개조할때 VCB 채용을 위한 참고자료로 쓰이도록 노력하였다.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.22 no.4
• /
• pp.715-722
• /
• 1998

A large electric system of a vacuum circuit breaker(VCB) has been studied for the electro-thermal analysis by finite element methods. Since the heat generation in VCB causes not only energy loss but deterioration of the VCB system with oxidization of parts, the overheating of the system must be prevented. For the analysis, a finite element formulation is derived for both electric analysis and thermal analysis that are coupled together. Two sets of formulations are uncoupled after finite dimensional approximation. First, the electric potential is obtained for the entire field and scaled to the given electric current. The electric field obtained is then used to calculate the heat generation in the VCB system including contacts and connections for the calculation of the temperature distribution in the entire domain. The finite element analysis is carried out to study the effect of shapes and locations of contacts and connections. From the results, the existing VCB has been modified to enhance its capacity with reduction of heat generation and temperature elevation.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.62 no.2
• /
• pp.190-195
• /
• 2013

Vacuum circuit breaker(VCB) has been widely used for interruption of load current and fault current for high voltage motor in the industrial field. Its arc extinguishing capability is excellent compared to other breakers. But it has the potential to cause multi reignition surge by high extinguishing capability. Surge voltage is generated by the opening and closing of VCB. Multi reignition surge of VCB is steep-fronted waveform. It may have a detrimental effect on the motor winding insulation. So, most of users install a protection device to limit steep-front waveform at the motor terminal or breaker side. So, most of users install a protection device at the motor terminal or breaker side. This protective device is surge absorber(SA) such as ZnO and RC type. In this study, we analyzed whether there is any effect when two type SA is applied to the VCB multi reignition surge. We confirmed that ZnO SA is slightly more effective than RC SA for reduction of multi reignition surge.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.31 no.5
• /
• pp.578-585
• /
• 2007

A vacuum circuit breaker (VCB) with permanent magnet actuator (PMA) has been studied in this study. Electromagnetic field analysis and dynamic simulations have been carried out for optimal design of VCB by using commercial software Maxwell and ADAMS. This simulation model can be an effective method for the VCB, which has non-linear output force of PMA, friction, and impact for operations. An experiment has been conducted to evaluate correctness of the simulated model. By using this evaluated model, the displacement and velocity characteristics of the VCB have been simulated with following conditions : (1) The different output forces of PMA have been applied, (2) The friction conditions in follow lever shaft and moving part have been changed, (3) The mass conditions of moving part have been changed. The simulated results shows that the velocity characteristics are mainly determined by the output force of PMA. The effects due to the changes of friction conditions against the dynamic characteristics was small, and the mass conditions of the moving parts affect the velocity and a bouncing phenomenon of VCB. From these results, the optimal design conditions for the VCB have been derived.

• Proceedings of the KIEE Conference
• /
• 1994.07a
• /
• pp.100-102
• /
• 1994

VCB, with its big arc extinction in very short switching time, produces the high switching surge voltage which may cause the breakdown of motor insulation or acceleration of insulation deterionation. To protect motor winding insulation, we developed the computer algorithm for simulating the surge occurred in VCB by EMTP. And we established the effect of the C-R surge absorber by the surge measurement in the motor-VCB circuit.

• The Transactions of the Korean Institute of Electrical Engineers B
• /
• v.52 no.8
• /
• pp.381-389
• /
• 2003

Nowadays, Vacuum Circuit Breaker(VCB) is used in the most medium voltage level because vacuum has environment-friendly characteristics as well as excellent dielectric strength. In order to elevate the breaking performance, the improvement of vacuum interrupters and the driving mechanism should be proceeded. In this paper, the development of a Permanent Magnet Actuator could replace the mechanical spring mechanism which is the driving mechanism of existing VCB. The holding force and opening characteristics of magnetic actuator are analysed with FEM and the result is verified through experiment.

• Proceedings of the KIEE Conference
• /
• summer
• /
• pp.878-880
• /
• 2004

In this paper, a new design of permanent magnetic actuator (PMA) for vacuum circuit breaker (VCB) with one coil is proposed. Electromagnetic characteristic analysis is performed numerically using finite element method (FEM) considering the nonlinearity of magnetic core and permanent magnet. The characteristics of proposed PMA with one coil is similar with that of the conventional PMA with two coils. The proposed PMA can simplify the control circuit because of the usage of one coil. Therefore, the reliability of VCB can be improved with the proposed model.

• Transactions of the KSME C: Technology and Education
• /
• v.3 no.2
• /
• pp.141-148
• /
• 2015

In this study, the VCB(Vacuum Circuit Breaker) has been developed using the Recurdyn that is widely used on multibody dynamics analysis. The VCB consists of three main circuits with the VI(Vacuum Interrupter) and the main frame with the operating mechanism. This analytic model is validated by comparing the simulation results and the experimental results. Generally, in order to reliably cut off the breaking current, the opening speed of the VCB after contact separation has to be a 0.9~1.1m/s. Therefore, the study of the design parameters of the VCB is needed. To improve the opening velocity, Taguchi design method is applied to optimize the design parameters of a VCB with a lot of linkages. In addition, to evaluate the improvement of the operating characteristics, the simulation results are compared with the Recurdyn and experimental results with improved prototype sample.

• Electric Engineers Magazine
• /
• s.376
• /
• pp.40-41
• /
• 2013

2013. 10. 27(일) 10:46경 경북 예천군 소재 XX 음료(주) 수변전실에서 ${\bigcirc}{\bigcirc}$공사 소속 A 과장이 전기설비 사용전 검사 중 VCB(진공차단기) 1차측 단자(22.9 kV)에 접촉되어 감전 사망한 재해임.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.67 no.9
• /
• pp.1159-1164
• /
• 2018

Vacuum circuit breakers(VCB) are widely used for current interruption of high-voltage inductive loads such as induction motors. This VCB can be chopped off before the current zero due to its high arc-extinguishing capability. One of the outstanding features of VCB is that it can cut off high frequency re-ignition current more than other circuit breakers. If the transient recovery voltage generated in the arc extinguishing is higher than the dielectric strength of the circuit breaker, a re-ignition phenomenon occurs. The surge voltage of the re-ignition is very high in magnitude and the steepness of the waveform is so severe that it can act as a high electrical stress on the winding. If the high frequency current of one phase affects the other two phases when the re-ignition occurs, it may cause a high surge voltage due to the virtual current chopping. If the magnitude of the voltage allowed in the motor winding is high or the waveform level is too severe, it may lead to insulation breakdown. Therefore, it is necessary to reduce the voltage to within a certain range. In this study, we briefly explain the various phenomena at the time of interruption, analyzed the magnitude of the dielectric strength and the transient recovery voltage at the simultaneous three-phase interruption that can give the greatest influence to the inductive load, proposed a method to reduce the impact.