• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1
  • Tagged with
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Integrated Current Sensor using Giant Magneto Resistive (GMR) Field Detector for Planar Power Module

Kim, Woochan 19 December 2012 (has links)
Conventional wire bond power modules have limited application for high-current operation, mainly because of their poor thermal management capability. Planar power modules have excellent thermal management capability and lower parasitic inductance, which means that the planar packaging method is desirable for high-power applications. For these reasons, a planar power module for an automotive motor drive system was developed, and a gate-driver circuit with an over-current protection was planned to integrate into the module. This thesis discusses a current-sensing method for the planar module, and the integrated gate driver circuit with an over-current protection. After reviewing several current-sensing methods, it becomes clear that most popular current-sensing methods, such as the Hall-Effect sensor, the current transformer, the Shunt resistor, and Rogowski coils, exhibit limitations for the planar module integration. For these reasons, a giant magneto resistive (GMR) magnetic-field detector was chosen as a current-sensing method. The GMR sensor utilizes the characteristics of the giant magneto resistive (GMR) effect in that it changes its resistance when it is exposed to the magnetic-flux. Because the GMR resistor can be fabricated at the wafer level, a packaged GMR sensor is very compact when compared with conventional current sensors. In addition, the sensor detects magnetic-fields, which does not require direct contact to the current-carrying conductor, and the bandwidth of the sensor can be up to 1 MHz, which is wide enough for the switching frequencies of most of motor drive applications. However, there are some limiting factors that need to be considered for accurate current measurement: • Operating temperature • Magnetic-flux density seen by a GMR resistor • Measurement noise If the GMR sensor is integrated into the power module, the ambient temperature of the sensor will be highly influenced by the junction temperature of the power devices. Having a consistent measurement for varying temperature is important for module-integrated current sensors. An experiment was performed to see the temperature characteristics of a GMR sensor. The measurement error caused by temperature variation was quantified by measurement conditions. This thesis also proposes an active temperature error compensation method for the best use of the GMR sensor. The wide current trace of the planar power module helps to reduce the electrical/thermal resistance, but it hinders having a strong and constant magnetic-field-density seen by the GMR sensor. In addition, the eddy-current effect will change the distribution of the current density and the magnetic-flux-density. These changes directly influence the accurate measurement of the GMR sensor. Therefore, analyzing the magnetic-flux distribution in the planar power module is critical for integrating the GMR sensor. A GMR sensor is very sensitive to noise, especially when it is sensing current flowing in a wide trace and exposed to external fields, neither of which can be avoided for the operation of power modules. Post-signal processing is required, and the signal-conditioning circuit was designed to attenuate noise. The signal-conditioning circuit was designed using an instrumentation amplifier, and the circuit attenuated most of the noise that hindered accurate measurement. The over-current protection circuit along with the gate driver circuit was designed, and the concept was verified by experiments. The main achievements of this study can be summarized as: • Characterization of conventional current-sensing methods • Temperature characterization of the GMR resistor • Magnetic-flux distribution of the planar power module • Design of the signal-conditioning circuit and over-current protection circuit / Master of Science
2

Conception caractérisation et mise en oeuvre d'un circuit intégré type driver en CMOS pour composants GaN / Design characterization and implementation of an integrated CMOS driver circuit for GaN components

Nguyen, Van-Sang 08 December 2016 (has links)
Le projet de thèse s'inscrit dans le consortium industriel académique MEGAN (More Electric Gallium Nitride) réunissant de nombreux industriels français, grands groupes et PME (Renault, Schneider Electric, Safran, IDMOS, Valeo...) et académiques (G2Elab, Ampère, SATIE...) et le CEA. Le projet consiste à introduire de nouvelles technologies de composants de puissance à base de matériaux en GaN afin d'augmenter les performances des convertisseurs statiques pour divers types d'applications. La thèse est intégralement focalisée sur la partie Driver intégré de composants GaN à base d'une technologie CMOS SOI XFAB XT018 pour favoriser l'utilisation des systèmes à haute fréquence et haute température. La thèse consiste à étudier des architectures des drivers et des fonctionnalités innovantes permettant de limiter les problèmes inhérents à la haute fréquence et la haute température (Compatibilité ÉlectroMagnétique- CEM, pertes de commande par courant de fuites, limites fonctionnelles...). Suite à l'étude des architectures à l'échelle du bras d'onduleur à base de composants discrets, un circuit intégré est conçu en collaboration avec les partenaires du projet. Le circuit intégré est alors réalisé avant d'être caractérisé puis mis en œuvre dans des démonstrateurs dans le cadre du projet. En particulier, des caractéristiques de réponses en fréquence et de tenue en température seront proposées. La mise en œuvre est conduite au sein même du module de puissance intégrant les composants de puissance en GaN, au plus près de ceux-ci pour favoriser les fonctionnements à haute fréquence. Le démonstrateur final peut servir plusieurs types d'applications de part sa versatilité. Le travail de thèse est alors plus spécifiquement orienté sur l'étude du comportement haute fréquence du driver et de l'ensemble interrupteurs avec fortes vitesses de commutation / drivers d’un bras d'onduleur. / This Ph.D work is part of the industrial academic project MEGaN (More Electric Gallium Nitride) involving many French companies (Renault, Schneider Electric, Safran, ID MOS, Valeo, ...), academic institutions (G2Elab, Ampere, SATIE ...) and CEA. MEGaN project aims are to introduce a new technology of the power components based on GaN materials, to increase the performance of the static converters for various applications.This research is highly focused on the integrated driver and other power device peripheral units for GaN-based components. This is done in SOI CMOS XFAB XT018 technology to promote performing in high-frequency and high temperature applications. It involves examining driver's architectures and features, innovative methods to limit problems inherent in high frequency and high temperature (conducted EMI perturbation, delay mismatch, functional limitations ...). After studying the architecture at the scale of the discrete circuits, the integrated circuits are designed in collaboration with the project partners. The integrated circuit is manufactured by foundry XFAB before being characterized and implemented.In particular, the characteristics at high frequency response and high temperature compliance are proposed. The final implementation is conducted in the hybrid power module power with the power components GaN, as close as possible to those for operation at high frequency which is presented in the end of this thesis. The final demonstrator serves several kinds of applications because of its versatility. The thesis is specifically focused on the study of high frequency behavior of the driver and power switches with high switching speed / the driver’s components of an inverter leg.

Page generated in 0.06 seconds