Suppressing Electromagnetic Interference in Switching Converters by Chaotic Duty Modulation

2017 ◽  
Author(s):  
Yuhong Song
Keyword(s):  
Frequency Band ◽  
Frequency Modulation ◽  
Electromagnetic Interference ◽  
Chaotic Signal ◽  
Industrial Applications ◽  
Switching Frequency ◽  
Switching Converters ◽  
Wide Frequency Band ◽  
Switching Converter ◽  
Driving Pulse

The switching converter generates serious electromagnetic interference (EMI), which impairs other devices‘ performance and harms human being’s health. As a way of chaos technique, chaotic modulation has been developed to suppress EMI of the switching converter by dispersing the energy into a wide frequency band and smoothing the peaks of the EMI spectrum. Unlike the well-studied chaotic frequency modulation, the chaotic duty modulation is concerned in this dissertation, which is just to change the duty of the transistor driving-pulse while maintains the fixed switching frequency. Chaotic duty modulation is realized by appending an external chaotic signal to the existing PWM module of the switching converter, which is practicable without the loss of the generality. It is thus verified that this proposal of using chaotic duty modulation in switching converters for EMI suppression is feasible and lays a foundation for industrial applications. ...

scholarly journals Electromagnetic interference of switching mode power regulator with chaotic frequency modulation

2002 ◽  
Vol 15 (1) ◽  
pp. 111-122
Author(s):  
Hei Wong ◽  
Yan Chan ◽  
Sui Wah
Keyword(s):  
Frequency Modulation ◽  
Electromagnetic Interference ◽  
Noise Level ◽  
Pulse Width Modulation ◽  
Chaotic Signal ◽  
Switching Frequency ◽  
Noise Power ◽  
Frequency Range ◽  
Switched Mode Power Supplies ◽  
Switching Mode

In this work, we propose an improved switching scheme (called chaotic frequency modulation (CFM)) for switched-mode power supplies to suppress the electromagnetic interference (EMI) noise source. The basic principle of CFM is to use a chaotic signal to modulate the switching signal so that the harmonics of noise power is distributed evenly over the whole spectrum instead of concentrated at the switching frequency. When compared with the conventional pulse width modulation (PWM) scheme, significant improvements in both conducted and radiated EMI noise levels were found with the proposed CFM method. For conducted EMI, the peak noise level was reduced by 25 dB_V. For radiated EMI, we found that the noise was found mainly in the frequency range of 30 MHz to 230 MHz and the CFM scheme would help to reduce the peak noise level in this frequency range by 22 dB_V.

Effects of Switching Frequency Modulation on Input Power Quality of Boost Power Factor Correction Converter

2017 ◽  
Vol 8 (2) ◽  
pp. 882 ◽  
Author(s):  
Deniss Stepins ◽  
Jin Huang
Keyword(s):  
Power Quality ◽  
Power Factor ◽  
Frequency Modulation ◽  
Spread Spectrum ◽  
Electromagnetic Interference ◽  
Power Factor Correction ◽  
Harmonic Distortion ◽  
Input Power ◽  
Switching Frequency

Switching frequency modulation (SFM) as spread-spectrum technique has been used for electromagnetic interference reduction in switching power converters. In this paper, a switching-frequency-modulated boost power factor correction (PFC) converter operating in continuous conduction mode is analysed in detail in terms of its input power quality. Initially, the effect of SFM on the input current total harmonic distortion, power factor and low-frequency harmonics of the PFC converter are studied by using computer simulations. Some advices on choosing parameters of SFM are given. Then the theoretical results are verified experimentally. It is shown that, from a power quality point of view, SFM can be harmful (it can significantly worsen the power quality of the PFC converter) or almost harmless. The results depend on how properly the modulation parameters are selected.

scholarly journals Conducted EMI of Switching Frequency Modulated Boost Converter

2013 ◽  
Vol 3 (1) ◽  
pp. 12-18 ◽  
Author(s):  
Deniss Stepins
Keyword(s):  
Frequency Modulation ◽  
Experimental Verification ◽  
Electromagnetic Interference ◽  
Modulation Frequency ◽  
Boost Converter ◽  
Switching Frequency ◽  
Research Papers ◽  
Theoretical Results ◽  
Analysis Line ◽  
Conducted Emi

Abstract In this paper conducted electromagnetic interference (EMI) of boost converter with switching frequency modulation (SFM) is theoretically analyzed in details. In the analysis line impedance stabilization network parameters, power inductor and input filtering capacitor parameters are taken into account. The analysis shows that the conducted EMI attenuation due to the use of SFM depends not only on modulation index as it is assumed in numerous research papers, but also on central switching frequency. Useful expressions to numerically calculate SFM boost converter conducted EMI spectrum and attenuation due to the use of triangular and sawtooth modulation waveforms are derived. Additionally experimental verification of the theoretical results is performed using a superheterodyne spectrum analyzer. Moreover a procedure for the choice of optimum SFM parameters (modulation waveform, frequency deviation and modulation frequency) to get maximum conducted EMI attenuation is proposed.

scholarly journals A Wideband Low-Pass Filter for Differential Mode Distortion

10.14311/1424 ◽  
2011 ◽  
Vol 51 (5) ◽  
Author(s):  
M. Brejcha
Keyword(s):  
Frequency Band ◽  
Switching Frequency ◽  
Switching Converters ◽  
Differential Mode ◽  
Pass Filter ◽  
Low Pass Filter ◽  
Pwm Converters ◽  
Low Pass ◽  
Specific Part

This paper deals with the solution for a wideband low-pass filter that can be used for filtering the input currents of switching converters, which are distorted by the switching frequency of PWM. Initially, the filter was proposed for the special type of AC converter, which is described in the paper. However, these solutions can also be used in the inputs of active PFC converters and in the outputs of PWM converters, where there are similar problems with switching frequency.The frequency band of the filter is given by the switching frequency of the filtered device and by the demands of EMC standards. This makes the filter able to work in the frequency band from 10 kHz to 30 MHz. To ensure such a frequency band, the filter should be proposed with two sections, each for a specific part of the band.

scholarly journals A Systematic Study on the Harmonic Overlap Effects for DC/AC Converters under Low Switching Frequency Modulation

Energies ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2811
Author(s):  
Ze Wang ◽  
Zhen He ◽  
Chao Gao
Keyword(s):  
High Power ◽  
Frequency Modulation ◽  
Heat Dissipation ◽  
Pulse Width Modulation ◽  
Low Frequency ◽  
Industrial Applications ◽  
Voltage Source ◽  
Switching Frequency ◽  
Ac Converters ◽  
Power Capability

In most high power industrial applications, the low switching frequency modulations (LSFM) are usually implemented to reduce power loss and heat dissipation pressure. However, there are some unexpected influences caused by the low order harmonic sinusoidal pulse width modulation (SPWM), such as the imbalanced submodule power in cascaded half-bridge inverter (CHB) and limited output power capability in H-bridge neutral-point-clamped (HNPC) converter. This paper starts by generalizing the basic characteristic of two-level SPWM, then deeply investigates the influences of low-frequency modulation on the operation of the circuits. They are classified into three mechanisms and generally named as harmonic overlap effect (HOE). The corresponding solutions to copy with the mechanisms are proposed and verified in some topologies through high-power simulations in simulations. In addition, a comprehensive summary of the influences and solutions of these effects on typical high power converters is drawn. The design rules of the modulation schemes for multilevel voltage source converters (VSCs) at low switching frequency are also proposed.

Nanoelectromagnetic of the N-doped single wall carbon nanotube in the extremely high frequency band

Nanoscale ◽  
2017 ◽  
Vol 9 (37) ◽  
pp. 14192-14200 ◽  
Author(s):  
B. Aïssa ◽  
M. Nedil ◽  
J. Kroeger ◽  
M. I. Hossain ◽  
K. Mahmoud ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Carbon Nanotube ◽  
Frequency Band ◽  
Electromagnetic Interference ◽  
High Frequency ◽  
High Electrical Conductivity ◽  
High Frequency Band ◽  
High Demand ◽  
Extremely High Frequency ◽  
Minimal Thickness

Materials offering excellent mechanical flexibility, high electrical conductivity and electromagnetic interference (EMI) attenuation with minimal thickness are in high demand, particularly if they can be easily processed into films.

Switching frequency modulation for GaN-based power converters

2015 ◽  
Author(s):  
B. Weiss ◽  
R. Reiner ◽  
R. Quay ◽  
P. Waltereit ◽  
F. Benkhelifa ◽  
...  
Keyword(s):  
Frequency Modulation ◽  
Power Converters ◽  
Switching Frequency

scholarly journals Physical Principles of a Piezo Accelerometer Sensitive to a Nearly Constant Signal

Sensors ◽  
2018 ◽  
Vol 18 (10) ◽  
pp. 3258 ◽  
Author(s):  
Valery Gupalov ◽  
Alexander Kukaev ◽  
Sergey Shevchenko ◽  
Egor Shalymov ◽  
Vladimir Venediktov
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Frequency Band ◽  
Linear Acceleration ◽  
High Sensitivity ◽  
Element Model ◽  
Wide Frequency Band ◽  
Piezoelectric Accelerometer ◽  
The Finite Element Model ◽  
Physical Principles

The paper considers the construction of a piezoelectric accelerometer capable of measuring constant linear acceleration. A number of designs are proposed that make it possible to achieve high sensitivity with small dimensions and a wide frequency band (from 10−5 Hz). The finite element model of the proposed design was investigated, and its output characteristic and scale factor (36 mV/g) were obtained.

Sign in / Sign up

Export Citation Format

Share Document