Common-mode Noise Generation Research Articles

Analysis of the bi-bridge topology and power device circuit of the TPS booster dipole power supply

This study primarily discusses a unique topology for constructing a double full bridge circuit. The study establishes a push-pull inverter model and analyses the balance circuit in its architecture. This allows the power supply to initiate the balance circuit and ensures the TPS (Taiwan Photon Source) booster magnet power supply operates smoothly in a safe and balanced voltage region when magnet energy is recovered. We employ the approach of adding Y circuits to mitigate the impact of common mode (CM) noise. Adding a Y circuit effectively suppresses the common-mode noise generation, improving the quality of the output current of the TPS dipole magnet power supply at low currents state and ramping the beam current energy from 150 MeV to 3 GeV. Furthermore, the reproducibility and stability of the injection point can enhance the injection efficiency of the TPS booster magnet power supply. This study presents the results obtained from these efforts.

Modeling of Conducted Emission for a Three-Phase Motor Control Inverter

This article presents modeling of the conducted emission of a motor control inverter using a lumped parameter circuit and finite-element (FE)-based three-dimensional (3-D) electromagnetic simulation. The objective of the modeling is to validate the circuit design and component selection as well as predict the conducted emission at the early design stage of the motor drive system. This model is useful to save time and cost of design iteration for any power electronic converter used in industrial applications. In this study, the main sources of conducted emissions of a power inverter along with a layout of complex geometry are identified. Then, analytical study along with circuit and FE-based electromagnetic simulation is used to implement the model of the motor inverter pair. The simulation model considers the board and component parasitic responsible for the common-mode current generation due to pulsewidth modulation switching. The effect of motor housing, harnesses, and chassis structure on common-mode noise generation is presented by the 3-D simulation model that cannot be realized in circuit simulation. The simulation model is validated with the experimental results that showed good correlation.

Mechanism of Common-mode Noise Generation in Multi-conductor Transmission Lines

The mechanism of common-mode noise generation in multi-conductor transmission lines is presented. Telegraphic equations, wave equations, and reflection coefficients in the normal and common modes are derived, which provide the mechanism of common-mode noise generation. In addition to coupling among transmission lines, the origin of the common-mode noise generation is elucidated by deriving the reflection coefficients in the normal and common modes.

Comparison Study of Common-Mode Noise and Thermal Performance for Lateral Wire-Bonded and Vertically Integrated High Power Diode Modules

This paper investigates the power module design for better common-mode (CM) noise and thermal performance. A high-frequency full-bridge diode rectifier is selected as a case study. The most influential factors in CM noise generation and mitigation are first identified with a simplified CM equivalent model and a comprehensive parametric study. Studies show proper parasitic value and parasitics symmetry can improve CM noise performance. The analysis of packaging structures indicates the vertical module has better CM noise and thermal performance than the traditional lateral wire-bonded module. To validate this, both modules are designed and prototyped for verification. The thermal simulation shows the vertical module exhibits a 25.5% lower thermal resistance from junction to case and a 51% increase of power density in a force-air-cooled condition. Experiments also reveal 15 dB of CM noise reduction from 150 kHz to 6 MHz and a 32% improvement of power density in a force-air-cooling condition. Finally, a case study demonstrates the vertical power module CM noise performance in a typical unsymmetrical topology. This results in a 30 dB CM noise reduction up to 6 MHz.

A Case Study on Common Mode Electromagnetic Interference Characteristics of GaN HEMT and Si MOSFET Power Converters for EV/HEVs

Wide bandgap semiconductors, such as gallium nitride (GaN)-based power devices have become increasingly popular in the automotive industry due to their low on-state resistance and fast switching capabilities. These devices are sought to replace silicon (Si) devices in power electronics converters for vehicular applications. GaN devices dissipate less energy during each switching event, thus, GaN converter designers can significantly increase the switching frequency without increasing switching losses, relative to Si converters. However, one item of concern is that the high $dv/dt$ of GaN devices, due to the increased switching speed, has the potential to deteriorate the electromagnetic interference (EMI) emission of power converters, and thus may fail the corresponding regulations for vehicles. To understand these effects, this paper presents an experimental case study on the switching characteristics and common mode (CM) noise generation of a GaN-based half-bridge configuration operating in the synchronous boost mode. A comprehensive comparison has been made between the chosen GaN high electron mobility transistors (HEMTs) and Si MOSFET in terms of switching voltage waveforms, ground leakage currents, and CM noise spectrum. By parametrically increasing the gate resistance of GaN HEMT and Si MOSFET, the tradeoff between converter efficiency and CM noise generation is also quantified.

A 5.8-Gbps low-noise scalable low-voltage signaling serial link transmitter for MIPI M-PHY in 40-nm CMOS

A scalable low-voltage signaling (SLVS) serial link transmitter for MIPI M-PHY is presented in this paper. It delivers 200---400 mV pp signals at date rates of 1.25---5.8 Gbps. The integrated circuit entity consists of the actual SLVS driver, an ADPLL-based clock synthesizer with a frequency multiplier, and an internal test signal generator with pseudo-random binary sequences. The circuit has been fabricated in a 40-nm CMOS process. The overall active die area is 0.2 mm2, while the actual driver occupies only 190 μm2. In this work it was confirmed that a low-power SLVS driver meets the stringent common-mode noise generation limits set for serial interfaces used in mobile devices. Noise power density remains below ?138 dBm/Hz at all data rates. Total power consumption of the transmitter is kept low by utilizing dynamic CMOS pre-drivers and a low drop-out voltage regulator. It achieves power efficiency of 0.44---1.4 mW/Gbps with external clock and 2.6---4.7 mW/Gbps with clock synthesizer.

Common Mode EMI Noise Characteristics of Low-Power AC–DC Converters

Low-power (below several hundred watts) ac-dc converters have unique common mode (CM) noise characteristics compared to higher power converters. A detailed CM noise model is derived in this paper to predict the original CM noise of such converters and to provide insight into CM noise generation and propagation. Further analysis on the model yields some general converter design rules for engineers to follow at the design stage in order to minimize the converter CM noise emission. The proposed model and design rules have been verified and demonstrated on a critical mode boost power factor corrector and a single-stage PFC converter.

Common-Mode Noise Generation in a DC-to-DC Converter

Analytical and experimental considerations of the common-mode noise in a dc-to-dc connverterare discussed. Analyzing the mechanism of the common-mode noise generation by means of a high-frequency equivalent circuit, we estimate the output noise voltage generated during the transistor's turn-on time. This commonmode noise consists mainly of two frequency components distributed in several megahertz. The effects of parasitic parameters on the noise voltage and frequencies are clarified. In addition, the effect of a common-mode choke on the noise suppression is discussed experimentally.