• Journal of Electrical Engineering and Technology
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• 제1권3호
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• pp.327-331
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• 2006

This paper presents the analysis method for the torque characteristic of the 1-phase induction motor considering space harmonics in the air gap. The equivalent circuit method is used, where the circuit constants are obtained by classic theory. In addition, the space harmonic components in air gap magneto motive force are analyzed and added to the equivalent circuit to obtain accurate torque characteristics in low speed regions. Each torque component due to the harmonics is calculated and the total torque characteristic is obtained and compared with the measurement result.

• Journal of Power Electronics
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• 제15권2호
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• pp.497-503
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• 2015

This paper analyses the harmonic pollution to power grids caused by several high-power rectifiers, summarizes the requirements for rectifiers in suppressing grid-side current harmonics and optimizes a new-type of current source PWM rectifier with a hybrid switch. The rectifier with a hybrid switch boasts significant current characteristics and cost advantages in the high-power area. To further enhance the working frequency of the current source rectifier with a hybrid switch for suppressing grid-side harmonics and reducing the inductance size, this paper proposes an optimal control strategy based on space vector. It also verifies that the optimal control strategy based on space vector can reduce the total harmonic distortion of the grid-side current of the rectifier with a hybrid switch via circuit simulation and experimental results.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1999년도 전력전자학술대회 논문집
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• pp.333-337
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• 1999

This paper presents the DQ transfomation space space vector modulation method to devel control algorithm of distribu STATCON(STATic CONdenser) for line volt regulation, dc link voltage regulation harmonics compensation. The Performance an of a PI with ramp comparision and synchro reference frame current controller is carried Based on these analysis, the control perform are desirable to compensate the harmonics a regulate dc link and line voltage of Distrib line.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.508-511
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• 1997

Recently the development of motor speed control systems with both good dynamic performance and simple implementation has been required. The vector control scheme considering flux harmonics for the permanent-magnet AC servo motor having low inertia, low weight, and high efficiency is proposed. To reduce the torque harmonics, current harmonics is employed. The vector control strategy is verified through digital simulation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 A
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• pp.133-135
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• 1997

In this paper, we propose a new type of rotor construction in the permanent magnet synchronous motor. By using plural permanent magnets for one-role of the rotor, it is possible not only to reduce space harmonics of air-gap fields but also to provide spacs for damper windings in the inter-pole space. The dimensions of the plural permanent magnets are derived by Fourier analysis. Based on the investigation by numerical analyses. we propose an optimal rotor construction in view of both the reduction of space harmonics and the damping effect.

• Journal of Astronomy and Space Sciences
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• 제41권2호
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• pp.87-106
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• 2024

The objective of this research is to address the issue of frozen orbits in charged satellites by incorporating geopotential zonal harmonics up to J6 and the initial tesseral harmonics. The employed model starts from the first normalized Hamiltonian to calculate specific sets of long-term frozen orbits for charged satellites. To explore the frozen orbits acquired, a MATHEMATICA CODE is developed. The investigation encompasses extensive variations in orbit altitudes by employing the orbital inclination and argument of periapsis as freezing parameters. The determined ranges ensuring frozen orbits are derived from the generated figures. Three-dimensional presentations illustrating the freezing inclination in relation to eccentricity, argument of periapsis, and semi-major axis parameters are presented. Additional three-dimensional representations of the phase space for the eccentricity vector and its projection onto the nonsingular plane are examined. In all investigated scenarios, the impacts of electromagnetic (EM) field perturbations on the freezing parameters of a charged satellite are demonstrated.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2000년도 추계종합학술대회
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• pp.669-672
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• 2000

This paper presents the methodology which analyze the effect of harmonics in power system. Considering the effect of less-harmonics, economic life and system loss, we have made the comprehensive countermeasure. According to the results of studying harmonics diagnosis and countermeasure, the following problems are pinpointed: protection of power system double investment space of the field. Therefore, in the initial stage, the countermeasure of harmonics trouble are set up. h a results, the following work has been done: $\circled1$ Generation source of harmonics and it's effect into en power system $\circled2$ Review of law related to harmonics, $\circled3$ Countermeasures to reduce the harmonics

• Journal of Electrical Engineering and Technology
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• 제3권3호
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• pp.373-378
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• 2008

In this paper, an Active Power Filter (APF) is implemented using a dSPACE DS1104 processor to compensate harmonics and reactive power produced by nonlinear load. The reference source current is computed based on the measurement of harmonics in the supply voltage and load current. A hysteresis based current controller has been implemented in a DSP processor for injecting the compensating current into the power system, so that APF allows suppression of the harmonics and reactive power component of load current, resulting in a supply current that is purely sinusoidal. Simulation and experimental results of the proposed APF to meet the IEEE-519 standards are presented.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 B
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• pp.1236-1238
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• 2000

This paper considers the problem of eliminating harmonics in the inverter output waveforms. The approach is based on the minimization of the current harmonics in the induction motor by space vector modulation method. Reference voltage is compensated with injection of controlled current harmonics which are calculated to reduce current harmonics through sampled current harmonic analyzing algorithm. The theoretical analysis is carried out using computer simulation. It is verified that proposed SVM technique could reduce current harmonic component and improve THD.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 A
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• pp.101-103
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• 1995

This paper describes new tecknique to obtain optimum value in calculating space harmonics in the motor design. First, develops general procedure in calculating slot harmonics, MMF harmonics, and systhesis of them. And then, trains Artificial Neural Network by classical method. Once trained ANN, it also computing different input data more quickly.