• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.23 no.4
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• pp.59-64
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• 2023

In this paper, It is proposed through the empirical design of a Conducted EMI filter for noise reduction of power used in electronic devices. For the proposed structure, A-type, B-type, C-type, and D-type structures were designed, and conductive noise reduction was confirmed by using an LC network with various X-capacitors, Y-capacitors, and Air-inductors. 10 [μH] was used for L1 and L2, and 4.7 [nF] was used for C1 and C2. L3 for common mode used 13[μH], and C5, C6, C7 were designed using 10[nF]. The measured insertion loss values of the designed EMI filter were -74.4[dB] at 3.2MHz, -75.4[dB] at 4MHz, and -75.3[dB] at 13.56MHz. Therefore, the proposed EMI filter will be able to reduce power supply noise used in various electronic devices.

• Journal of Power Electronics
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• v.14 no.4
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• pp.806-813
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• 2014

Planar electromagnetic interference (EMI) filters are widely used to restrain the conducted EMI of switching power supplies. Such filters are characterized by small size, low parasitic parameters, and better high-frequency performance than the passive discrete EMI filter. However, EMI filter performance cannot be exactly predicted by using existing methods. Therefore, this paper proposes a method to use scattering parameters (S-parameters) for the measurement of EMI filter performance. A planar EMI filter sample is established. From this sample, the relationship between S-parameters and insertion gain (IG) of EMI filter is derived. To determine the IG under different impedances, the EMI filter is theoretically calculated and practically measured. The differential structure of the near-field coupling model is also deduced, and the IG is calculated under standard impedance conditions. The calculated results and actual measurements are compared to verify the feasibility of the theory.

• Journal of Convergence for Information Technology
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• v.11 no.5
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• pp.57-65
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• 2021

Purpose: To analyze students' attitudes toward English-Medium Instruction (EMI) classes for nursing students. Methods: From January 23 to January 30, 2020, a survey was conducted using a web-based survey program on student attitudes, satisfaction, and improvement measures for EMI classes. 216 responded to the survey, giving a response rate of 63.7%. Results: The item with the highest score on the attitude toward EMI lectures was 'EMI classes will be of great help to student's future'. The item 'I will try to speak English with my classmates outside of the EMI class if possible' showed the lowest score. Students answered that they need an appropriate educational environment for the smooth operation of EMI classes, fewer students per class and support for group studies

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1881-1884
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• 2003

In some requirements of dc motor drive circuit applications are high quality output with generation of low internal conducted EMI. However the conventional dc motor drive circuits have been usually using unbalanced circuit which generates the high conducted EMI to the frame ground. This paper presents a balanced dc motor drive circuit which is effective way to reduce the common-mode noise. The circuit balancing is to make the noise pick up or occurring in both conductor lines, signal path and return path is equal in amplitude and opposite phase so that it will cancel out in the frame ground. The common-mode conducted noise reduction of this proposed dc motor drive is confirmed by experimental results.

• Proceedings of the KIPE Conference
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• 2002.07a
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• pp.542-545
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• 2002

This paper deals with the optimization inverter design and minimization Conduced EMI noise by customizing IPM(Intelligent Power Module). Generally, In case of IPM, we realized that the trade-off relation between switching loss and spike voltage. Higher gate resistor causes tile lower spike voltage and the higher turn-off switching loss. But we know that the life cycle of inverter and the susceptibility of noise, so we optimized the gate resistor. Proposed method is that optimized the gate resistor suitable for the inverter and motor. The simulation and experimental results show that the spike voltage and Conduced EMI noise can be reduced without the additional circuit.

• Journal of Power Electronics
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• v.18 no.3
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• pp.871-878
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• 2018

In this paper, the conducted EMI reduction performances of active feed-forward current-sensing current-actuation (CSCA) and voltage-sensing current-actuation (VSCA) filters for a three-phase induction motor drive system are evaluated by experiments. For comparison purposes, the conducted EMI (CM emission, DM emission and total emission) of a three-phase induction motor drive with a conventional CM choke, a conventional CM choke in series with an active VSCA filter, and an active CSCA filter (where the CM choke was modified and used as a sensing current transformer) were compared to the case of a system without any filter inserted. Experimental results show that the active CSCA and VSCA filters can improve the CM reduction performance of the conventional CM choke by about 5 dB especially at low-frequencies. However, for DM comparisons, it shows that there is no different between cases with and without filters inserted.

• Proceedings of the KIEE Conference
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• 1998.07f
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• pp.1876-1878
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• 1998

For an analysis and simulation of the conducted EMI of switching converters, an accurate simulation model for MOSFET is needed. This paper presents a new modeling approach, which incorporates DC output characteristics and AC dynamics especially the parasitic capacitances. It uses Pspice ABM(Analog Behavioral Model) and the MOSFET parameters can be obtained from the Data sheet in the frequency range of interest for EMI analysis. The model verified with an experimental setup and the EMI for a test converter is analyzed with respect to the MOSFET switching waveforms.

• Proceedings of the KIPE Conference
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• 2005.07a
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• pp.321-324
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• 2005

This paper describes the application of newly developed conducted EMI reduction technique of SVPWM in induction motor drive. The newly developed common mode voltage reduction SVPWM technique doesn't any zero-voltage vector states for inverter control. Hence it can restrict the common mode voltage better than conventional PWM technique. The proposed technique is verified through simulation and experimental results. And by applying vector-controled system, the proposed technique have superior ability of reducing EMI and equal control performance comparing conventional SVPWM technique.

• The Transactions of the Korean Institute of Power Electronics
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• v.4 no.6
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• pp.579-588
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• 1999

This paper presents a technique for predicting the conductLu EMI(Electro Magnetic Interference) produced b by PWM inverter-induction motor drive system. To obtain the simulation models for prediction of conduct떠 n noise, high frequency model of an inverter leg with parasitic elements and multi-coil model of stator winding M are designed. Finally, the results are confirmLu from simulation and experiments.

• Proceedings of the KIEE Conference
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• 1995.07a
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• pp.212-215
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• 1995

In this paper, The characteristic of Harmonic spectrum is studied for generally used three-phase diode rectifier. and filter design criteria is showen in the sense of THD, DPF, and PF. As the becoming of Automative and informative era, the demand of critical and stable control becomes more and more important. But much EMI emissions are generated for more critical and stable control in power electronic system these EMI emissions can be measured using LISN(Line Impedance Stabilization Network). So we are to investigate the behavior of Conducted EMI emission in Diode Rectifiers using LISN in frequency domain.