Thesis defense of David Garrido Diez


Thesis defense of David Garrido Diez


Thesis defense of David Garrido Diez

Title of the thesis: "Impacto de los semiconductores de banda prohibida ancha en el diseño de convertidores de potencia". Obtained the SOBRESALIENTE qualification.



  • Title of the thesis: "Impacto de los semiconductores de banda prohibida ancha en el diseño de convertidores de potencia"
  • Court:
    • President: Francisco Javier Sebastián Zúñiga (Universidad de Oviedo)
    • Vocal: Silverio Álvarez Hidalgo (ABB Coorporate Research Center)
    • Vocal: Carlos Bernal Ruiz (Universidad de Zaragoza)
    • Vocal: Estanislao Oyarbide Usabiaga (Universidad de Zaragoza)
    • Secretary: Gonzalo Abad Biain (Mondragon Unibertsitatea)


Electronic power converters are based on semiconductor devices for the conversion and control of electric power. Silicon is at the present time the most widely used material for the construction of these semiconductors. The technology of the production of silicon semiconductors allow them to be made without any manufacturing fault. However, physical limits of this material are being met, that is why significant advances are not expected in terms of efficiency, capacity of blocking voltage or capacity of evacuating the heat.

In this scenario, in the last years, wide BandGap devices (WBG) have appeared, which have the capacity of operating at higher switching voltages, temperatures and frequencies than silicon devices, while they maintain efficiency levels higher than those of the silicon. This way, the use of these Wide BandGap semiconductors allows the development of electronic power converters that have less volume and weight (higher density of power), with less heat evacuation requirements and more efficiency.

In order to make the most of the of the advantages of these devices, you must operate at high frequencies, which requires to work with fast transients of power (di/dt) and tension (dv/dt) to maintain acceptable efficiency levels. This requires at the same time improvements in the physical design of the layout that make the power circuit with the objective of reducing its parasitic inductance. This is because the level of parasitic inductance valid for silicon dynamics can limit the use of silicon carbide components. These considerations can be transposed to where the high switching dynamics of the silicon are source of noise.

In this context, the main objective of this thesis is to determine the impact of Wide BandGap semiconductors in the design of power converters.

In general terms, this thesis has two main parts. On the one hand, a state of the art of Wide BandGap semiconductors is carried out, these are evaluated experimentally, and drivers are designed for their right administration. On the other hand, this knowledge is applied to the design, development and validation of a quick battery charger for electric vehicles.

Among the contributions of the thesis, the following are emphasized: the work done regarding measurement techniques of fast switching transients, the development of a driver for silicon carbide MOSFETs capable of protecting the semiconductor from short circuits of less than 2 µs, as well as the design and development of a quick battery charger for electric vehicles based on MOSFET modules of silicon carbide.