• Proceedings of the Korean Nuclear Society Conference
• /
• 2005.10a
• /
• pp.975-976
• /
• 2005

• Journal of Electrical Engineering and Technology
• /
• v.13 no.6
• /
• pp.2262-2267
• /
• 2018

In electric machine design, there is a large computation cost for finite element analyses (FEA) when analyzing nonlinear characteristics in the machine Therefore, for the optimal design of an electric machine, designers commonly use an optimization algorithm capable of excellent convergence performance. However, robustness consideration, as this factor can guarantee machine performances capabilities within design uncertainties such as the manufacturing tolerance or external perturbations, is essential during the machine design process. Moreover, additional FEA is required to search robust optimum. To address this issue, this paper proposes a computationally efficient robust optimization algorithm. To reduce the computational burden of the FEA, the proposed algorithm employs a useful technique which termed static analysis assisted technique (SAAT). The proposed method is verified via the effective robust optimal design of electric machine to reduce cogging torque at a reasonable computational cost.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.18 no.2
• /
• pp.192-198
• /
• 2013

The rapidly growing demand for electric power systems in electric vehicles (EVs) and hybrid electric vehicles (HEVs) require simpler, cost-effective, and higher performance components. In this paper, a novel power conversion system for hybrid electric vehicles is proposed for these needs. The proposed power conversion system reduces the conversion system cost while preserving same functionality. The proposed power conversion system can boost multi-sources to drive a traction motor and to store energy at the same time reducing number of switching components. In this paper, all operational modes of the proposed converter are explained in detail and verified by a computer simulation first. Then, the topology and operational modes are experimentally verified. Based on the results, the feasibility of the proposed multi-mode single leg power conversion system for EV and HEV applications is discussed.

• Proceedings of the KIPE Conference
• /
• 1998.10a
• /
• pp.851-854
• /
• 1998

In recent years, a cost-effective voltage-source type single-ended resonant-load inverter using MOS gate power switching devices and its related resonant inverter topologies have been commonly used for induction-heated cooking appliances because of relatively-lowered switching losses, simple circuit topology, low cost, compactness and low harmonic current in utility AC side. This paper present some comparative performance evaluations of IGBTs as sample devices in each generation and MOS controlled Thyristor(MCT) incorporated into the voltage-source type single-ended load resonant inverter for induction-heating rice cookers used for consumer power electronic applications, in which the output power can be regulated on the basis of Frequency Modulation Scheme.

• Proceedings of the KIEE Conference
• /
• 2002.11b
• /
• pp.15-19
• /
• 2002

To provide a specified power quality under electric market system is becoming an important issue for customers and utility company. However, there is no realistic infra-structure to design a power system for the specified power quality. Present electric market is operating under the economic point of view. The low price could be attractive. but the effect of low price and low power quality for the long time should be considered for the system safety. This paper presents a model which conceptualize the dynamic power quality control mechanism to minimize total cost of a society which is affected electric power quality. This model aims to produce a basic infra-structure to balance cost and quality under the electric market system.

• Proceedings of the KIEE Conference
• /
• 2000.07a
• /
• pp.142-146
• /
• 2000

This paper Presents a heuristic algorithm based on branch exchange method to solve ORP (Optimal Routing Problem) for distribution system planning. The ORP is a complex task which is generally formulated as a combinatorial optimization problem with various constraints. The cost function of ORP is consisted of the investment cost and the system operation cost that is generally expressed with system power loss. This paper also adopt an specialy designed selection method of maximum loss reduction loop and branch to reduce optimization time. The effectiveness of the proposed algorithm was shown with 32, 69 bus example system.

• Journal of international Conference on Electrical Machines and Systems
• /
• v.1 no.2
• /
• pp.105-110
• /
• 2012

This paper designs the high-efficiency and the low-cost drive system of the smallsize electric vehicles (EVs). The power circuit for driving the dc motor is designed by considering both the cost and efficiency. In order to reduce the conduction loss of MOTFET and diode for controlling an armature voltage, some MOSFETs and diodes at the armature are in parallel connection. An operating sequence for both the field current and the armature voltage according to the accelerator pedal angle is suggested for changing smoothly the rotating direction of dc motor. Through the simulation studies, the performances of the proposed methods are verified.

• Proceedings of the KIEE Conference
• /
• 1990.07a
• /
• pp.96-99
• /
• 1990

Recently, electric energy consumption pattern shows very high peak load with low load factor. This Load pattern have made electric utilities be interested in Load Management, many studies are reported. But most of these studies are concerned with Rate - Load shape relation, a few of these are concerned with generating cost reduction. In this study, the effect of Load Management is incorporated to establish optimal Generation Expansion Planning. Using avoided cost, optimal generation expansion planning is achieved to make maximum avoided cost of Electric utility. Dynamic programming technique is used to solve this algorithm.

• Proceedings of the KIEE Conference
• /
• 1999.07c
• /
• pp.1270-1272
• /
• 1999

The generator cost function is one of the basic data for the generation scheduling. Generally the cost functions are obtained form design calculations or from heat rate tests. The real operating condition may be different from the condition of design or the tests. Some of the conditions may not be tested during the periodical maintenance. In order to improve the calculation of the generator cost function, this paper presents a new calculation method of the generator cost functions using the utilization factors of generators and the mixed fuel burning ratio of the generators.

• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.54 no.10
• /
• pp.496-499
• /
• 2005

In many parts of the world, the electric power industry is undergoing unprecedented changes. Therefore, in order to reform the electric power industry efficiently and minimize the confusion of this restructuring, the systematic studies related to transmission pricing and transmission cost allocation issues are required essentially. However, even now, the basis of transmission cost allocation rate is not equipped so that the regulation body has determined the allocating rate under the common practice. In this paper, we demonstrate that the decision of transmission cost allocation rate is the regulation body's own right. For this analysis, we apply game theory to the procedure determining this rate and the competition to determine this rate between gencos and distcos is modeled as the arbitration game.