• Proceedings of the KIEE Conference
• /
• 2007.07a
• /
• pp.142-143
• /
• 2007

A 1MW class HTS(High-Temperature Superconducting) synchronous motor has been developed. This motor is aimed to be utilized for industrial application such as large motors operating in large plants. The HTS field coil of the developed motor is cooled by way of Neon thermosiphon mechanism and the stator coil is cooled by water through hollow copper conductor. This paper describes performance test results of our motor, which was conducted at steady state in generator mode and motor mode.

• Journal of the Korean Magnetics Society
• /
• v.5 no.2
• /
• pp.103-108
• /
• 1995

We propose an analyzing method of the harmonics of output voltage in salient pole syochronous generator. In simulation, 2-D finite elerrent method is used for calculating the stator coil flux linkage considering the rotor movement. As an application of the proposed method, we calculated the harrronics of output voltage in the 150 kw class syochromus generator and compared it with the experirrental result.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2005.05a
• /
• pp.668-673
• /
• 2005

This paper proposes a simple actuator with a spherical rotor for robot's eyeball, which has two degrees of freedom. It features that both permanent magnets and coils are equipped in a stator and the spherical rotor with steps on its surface is driven by reaction of Lorentz force acting on the fixed coils. Such a structure is helpful to design a simple actuator and particularly suitable for a spherical actuator. Based on the FEM analysis, design parameters such as the sizes of core and permanent magnet, the width of step, coil turns and maximum current, are determined so as to maximize the torque and rotating angle. For the experimental verification of the feasibility, a prototype is manufactured and its operating characteristicsareinvestigated.

• Proceedings of the KIEE Conference
• /
• 1991.07a
• /
• pp.286-291
• /
• 1991

Most of the failures of rotating machine are stator coil insulation failures. The insulation diagnostic testing for high voltage motors and generators are only megger test and P. I Test which is applied DC voltage until now. But it was impossible to judge insulation deterioration status of high voltage rotating machinery by above testing. In other words, even though the megger measurement values are fairly high, they used to be failed from time to time. Therefore in order to excute reliable and detailed diagnosis of insulation deterioration for rotating machinery, the tangent delta test, the alternating current test and the partial discharge test shall be applied to the insulation diagnostic testing on site.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.7 no.6
• /
• pp.537-545
• /
• 2002

This paper presents a new method of detecting rotor position in Toroidal Switched Reluctance Motor(TSRM). In this paper, low cost and robust characteristics of rotor position detection method are focused in order to compensate for disadvantage of existing sensors. Search coils wound around stator poles are used for detection of rotor position in TSRM. Rotor position detection is achieved through electromotive force patterns induced by time-varying flux linkage in the search coils and then adequate phase is excited for drive. The validity of the method is verified by experimental results.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2007.05a
• /
• pp.46-50
• /
• 2007

The nuclear power plant's turbine-generator system had been suffered form some problems, such as high shaft vibration, generator casing crack, stator coil water leakage, high $H_2$ gas consumption rate. Those kinds of problems were related to high vibration. So nuclear plant decided to replace generator in order to reduce rotor high vibration and high thermal sensitivity. A series of effort to reduce turbine-generator vibration was carried out as followings, first of all, replacement of generator, analysis of turbine-generator vibration, LP B rotor shop balancing, improvement of LP B/Gen coupling run-out, improvement of Generator basement and field balancing. Finally the nuclear turbine-generator's shaft vibration was reduced below $60{\mu}m$ from over $200{\mu}m$ which is very excellent vibration in nuclear turbine-generator in Korea.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.67 no.1
• /
• pp.52-60
• /
• 2018

The winding of the motor stator coil is broken due to external stress and various factors. If the proper current is not injected when interturn fault(ITF) occurs, the fault can easily be expanded and the motor can be finally destroyed, resulting in many problems with time costs and safety. In this paper, the power loss limit concept, which is the inherent durability of each motor, is applied to secure safety by controlling the total power loss of the motor within the limits. So, we propose an algorithm that can control maximum torque per minimum power loss based on constant torque curve and power loss limit. To verify the proposed method, the simulation and experimental results with an Interior permanent magnet synchronous motor(IPMSM) having an ITF are shown.

• Proceedings of the KIPE Conference
• /
• 2004.07b
• /
• pp.686-690
• /
• 2004

This paper describes the performance improvement of transient response and the modeling of small aircraft onboard generator. As the characteristics of the stator coil which are a major parameters of transient response were improved, the characteristics of transient response could be increased, therefore, the improved generator can be satisfied with large and fast load changes. Established the control model of the generator, it could be possible to do the analysis of generator performance, and improve the operational stability of the generator system using the control model.

• Proceedings of the KIPE Conference
• /
• 2004.07a
• /
• pp.196-200
• /
• 2004

This paper presents a new method of detecting rotor position in Toroidal Switched Reluctance Motor(TSRM). In this paper, low cost and robust characteristics of rotor position detection method are focused in order to compensate for disadvantage of general sensors. Search coils wound through the hole of the stator poles are used for detection of the rotor position in TSRM. Rotor position detection is achieved through electromotive force patterns induced by time-varying flux linkage in the search coils and then adequate phase is excited for drive. The initial rotor position estimation method is also described. The validity of the method is verified by experimental results.

• Proceedings of the KIEE Conference
• /
• 2001.07b
• /
• pp.804-806
• /
• 2001

In this paper, by designing ratio width of the permanent magnet versus the stator coil, double excitation LDM with multi-separated winding which is possible to obtain the constant thrust force is proposed. Using Empulse, this paper has explained a various excitation mode to analyze the thrust force of multi-separated winding LDM. The simulation results show single-phase excitation mode have low thrust force ripple.