• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.06a
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• pp.465-466
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• 2008

• Proceedings of the KIEE Conference
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• 1989.11a
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• pp.53-57
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• 1989

Until now, method of equivalent circuit is generally used in analyzing the characteristic of the synchronous alternator. But this method can't apply when loads are connected to alternator. In this paper, we analyzed the load characteristic of the synchronous alternator with permanant magnet using 2-dimensional finite element method having voltage source. The loads of a alternator are battary and diodes which are used to rectify. also, we used half periodic boundary condition in the F.E.M calculation

• Proceedings of the KIEE Conference
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• 1999.11b
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• pp.24-26
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• 1999

In this paper, the conceptual design and FE analysis results of salient pole type alternator under no load condition are described. The designed alternator's rating is 180kW, 3-phase, 4pole, 380/220V, 0.8pf, 60Hz. The conceptual design is described by the process of designing the armature, field, and obtaining some of equivalent circuit parameters. The comparison of FE analysis to the designed results of alternator's output voltage value shows a good agreement.

• Proceedings of the KIEE Conference
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• 1993.11a
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• pp.73-75
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• 1993

In this paper, the transient shielding characteristics of slitted electrothermal shield of superconducting alternator is studied. The field current and the armature currents variations during three phase short circuit fault are calculated and compared to those of the conventional one. And the response of the armature current due to step-up of the excitation voltage showes the feasibility of the quick response excitation system available for improving the transient stability.

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.1
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• pp.9-16
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• 2011

Research on ISA(Integrated Starter/Alternator) receives wide attention as system voltage is increased to 42V Based on requirement of starter and alternator for the conventional vehicle, system requirement and specification are determined. Also to control proposed system, suitable control methods are proposed. Main control issues with ISA are whether torque assist is required and if so how much torque is needed. In this paper, vehicle performance with various control methods and capacity are simulated and simulation results are analyzed. Vehicle performance is analyzed with vehicle simulator. For the simulation, suitable ISA model is also developed.

• Proceedings of the KIEE Conference
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• 2000.11d
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• pp.669-671
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• 2000

Vehicle electric power system, which consists of two major components; an alternator and a battery, supplies electric power to vehicle electric and electronic systems. In recent years, bigger power supply is required for the rapid demand of the number of vehicle electric and electronic systems. It is important that vehicle power system should be analyzed exactly. For the simulation of vehicle electric power system, appropriate component model of vehicle electric power system should be chosen. In this paper, a simplified and accurate battery model is developed to obtain the battery parameters, and a Variable Alternator Terminal Voltage Model is introduced to described an alternator. The case study shows that simulation results using the suggested models are well agreed with the experiments.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.10
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• pp.5899-5905
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• 2014

Faults in electric power system can be a critical problem for vehicles. The system durability is determined mainly by the durability of their components and operating conditions. Monitoring the conditions of the electric power system may be necessary because it is very difficult to predict precisely when it will fail. Therefore, the aim of this study was to develop a diagnosis system for an electric power system of a vehicle. The alternator voltage, excitation voltage, lamp voltage, battery voltage, and engine rpm from a crank angle sensor are monitored continuously and the system fault can be then detected in real time. NI USB- 9201 DAQ and LabVIEW SW have been used to measure the voltages and analyze the data. Compared to conventional measurements for only each component, an integrated and portable measurement method was developed. In addition to the monitoring the electric power system in real time, the saved data from the measurement also provides valuable information to improve the durability of the components.

• The Transactions of the Korean Institute of Power Electronics
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• v.21 no.2
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• pp.182-189
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• 2016

A modeling method of electric power network inside a fishing boat less than 5 tons is proposed for its high-energy efficiency with renewable energy sources. The power network inside the fishing boat consists of a diesel engine, a starter motor, an alternator, battery packs, and electric loads, which are connected in parallel. To obtain proper power network model, the voltage -current characteristics of the electric components are considered to develop elaborate electrical models under several load conditions. Measured data of the battery and alternator current include noise. By using an average method, the AC components from the power network of the fishing boat can be reduced, which is verified by KCL rule. Using the proposed power network model, the power generation of the alternator and the reduction of diesel consumption in the boat's engine are predictable under various operating conditions. The validity of the proposed methodology is verified by comparing simulation results with experimental measurements using statistical inferences.

• Journal of the Institute of Convergence Signal Processing
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• v.16 no.4
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• pp.182-188
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• 2015

An analog AVR has an advantage of short time constant, time to revert again from the abnormal state to a stable one depending on the voltage fluctuations of the load. But the Analog AVR has a disadvantage of large voltage variation according to the load fluctuation. Voltage regulation for digital AVR is very stable, but the time constant is very long compared to that of an analog AVR. Therefore, it indicates that the digital AVR shows unstable output performance in a very large load variations. In this paper, a mixed form of an analog AVR and a digital AVR is proposed. An implemented hybrid AVR has fast time constant and stable voltage regulation capability. Hybrid AVR voltage variations in the load is stable within 1[%] and the voltage stability is also improved. It also showed fast time constant to the level of the analog AVR. Thus hybrid AVR developed in this paper can be used as a power supply for a variety of uses in industry.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.24 no.1
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• pp.124-129
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• 2015

The performance of a passenger vehicle has been greatly improved recently owing to the intensive use of electronic controllers. Many components of a vehicle, including the engine, are controlled by electronic systems installed in the vehicle. Therefore, the electrical power required for such electronics has increased significantly. However, the electrical power generated by the vehicle's alternator, operated by the engine, is limited, and when the vehicle is started, a large instantaneous current is required. The voltage of the vehicle electrical system fluctuates to a very low level, then, it is gradually recovered. This case is very severe and can even cause damage to electronic systems. In this study, a voltage-stabilizing module comprising electric double layer supercapacitors, which could alleviate the voltage variation, was developed and tested.