Thermal Behavior of Paralleling IGBTS

Using multiple smaller chips instead of one larger chip improves the thermal behavior, as they doesn`t heat as quickly as a larger one, they tend to devides the heating properties well, This is due to the fact that not only the chip itself, but also a certain area around the chip, will participate in the transfer of heat from the chip to the heatsink. Parallelling systems have improved thermal spreading when using two small chips instead of one large, with in equal total area in both cases.

This case can also be seen when comparing the thermal resistance of the 100 A IGBT in the P569-F module with the 35 A IGBT in the P700-F module. The thermal resistance junction to heatsink for the 100 A the device is 0,57 K/W. The resistance for the single 35 A IGBT is 1,29 K/W, resulting in an  resistance of 0,43 K/W, when 3 of them are used in parallel. This provides an improvement of about 25 % in thermal performance,one point for these kind of system, that left behind the more traditional one-module igbt old system, this also compensates for some if not all of the de-rating required due to the non-ideal current sharing.

Paralleling Systems for IGBTs and their Improvement

Widespread application of IGBTs in the past two decades has resulted in dramatic improvement in performance of power electronic converters, the efficiency of these devices has made its mark, reducing the cost of power electronic systems and  improving their own reliability, making them the first option of the manufacturing industry, Paralleling systems for IGBTS and diodes is one of the best alternatives to achieve a best performance.

The conclusion is that paralleling systems for igbts provides an advantage due to the improved thermal behavior of several small chips rather than fewer big ones. The breakthrough in performance is seen when real life data of parameter variations within one power module are considered, instead of the datasheet values, which suggest a much higher spread than actually seen in real life.

ON-STATE BEHAVIOR FOR PARALLELING IGBTS

The on-state behavior is something more critical when it comes about paralleling igbts. Some devices such as the P700 sixpack suggests a relatively variation in IGBT collector-emitter and diode forward voltage. For the IGBT, the collector-emitter saturation voltage at 25 °C is given as 1.7 V typical and 2.25 V maximum. No value is provided for the minimum voltage. Keeping this in mind, the paralleling of chips cannot be recommended, since the current sharing among the individual IGBTs cannot be ensured. The situation is even worse for the diodes in parallel systems but it can be avoided depending it its final use.

However based in the present times, the actual spread of the devices within one power module is lower than the parallel system users. This is due to the fact that they are picked from locations either exactly next or very close to each other on the same wafer, and will as is stated, feature similar electrical characteristics.

LASTEST DUAL HIGH VOLTAGE IGBT MODULES TARGETS THE HEAVY INDUSTRIES

Mitsubishi  developed the X series of dual IGBT modules, samples of a  3.3. kv ( LV100 with 6KV isolation taking up to a  450A) will be available for shipping from March next year (2017), then 1.7 kb, 3.3 kv, 4.5 and 6.5kv versions in that order, they will be all available from 2019 onwards (with a  10kv isolation)

This device will satisfy demand for efficient and high power density semiconductors, they will be contributing to higher power outputs and efficiency by adopting the lastest diodes for IGBTs and RFCs, standardized 100x140x40 package dimensions will allow the manufacturing industry to simplify the design and secure multiple sources for inverters.

Mitsubishi Electric Improves Speed of World's Fastest Elevators

Mitsubishi made one of its greatest announcements for this year; the development of an elevator technology that achieved an speed of 1,230 meters per minute or 20,5 per second, the fastest elevator speed in the world as it`s known!, this technology will be installed to one of three elevators at the Shanghai Tower, China`s tallest building.

This was achieved through the creation of new equipment, that includes a  control panel tant can maximize the traction`s machine`s performance , and great improvements of safety devices, once the elevator is equipped with this technology it can travel from second level basement to the tower`s 119^th floor in just 53 seconds! Impressive!

About Shanghai Tower

Shanghai Tower is located in the Lujiazui Finance and Trade District of Pudong, Shanghai. It houses offices, a hotel, conference and exhibition halls, restaurants and facilities for commerce, culture and sightseeing.

Infineon Raises SIC Mosfet to a Whole New Era of Improved Technology

Devices that raise the technology to a  whole new level, using SIC MOSFETS allows conversion to operate at triple or more the switching frequency leading to benefits, something  that was impossible until now, Dr Helmut Gassel, president of infineon`s Industrial Power control said these devices reached a  whole new level which has never before been possible, they are smaller and contain a lighter system for less transportation and easier installation.

As we arrive to a new era filled with new possibilities technology keeps changing, the SiC MOSFETs is a prove of this, it has been optimized to combine reliability with performance. They operate in a magnitude lower than 1200 V, this reduces the dynamic losses and also supports system improvements in applications such as photovoltaic inverters and charger/storage systems among others, this also extend the support to industrial drives and the durable life of the devices.

These  MOSFETS are fully compatible  with +15 V/-5V voltage typically used to drive IGBTs, their structure combines a benchmark  threshold voltage rating (V th) of  4V with a  short circuit robustness which is required by the target applications  and fully controllable dv/dt characteristics, This initially supports system improvements in applications such as photovoltaic inverters, uninterruptible power supplies (UPS) or charger/storage systems, while later configurations will also extend support to industrial drives.

The latest evolution of Infineon`s comprehensive family of cool SiC technologies includes schottky diodes , 1200 V J- FET devices and a  range of hybrid solution that integrates a better battery charging, energy storage and the integration of a  commutation  robust  body diode operating with nearly zero  reverse recovery losses.

For Infineon this is the culmination of years  of experience and improvements, truly something to keep an eye on.

El MOSFET un recuerdo vago para el IGBT

En los tiempos actuales, donde es reinventarse o morir hay algo que puede ser acuñado a  todo, inclusive, la tecnología, y es aprender de las fallas de nuestros predecesores, en este caso el IGBT siempre presenta mejoras de los aparatos que vinieron antes que el.

La estructura recuerda mucho la de un transistor MOSFET de potencia donde se utilizan obleas dopadas de Tipo N sobre las que se deposita una fina capa epitaxial. El IGBT está construido de forma casi idéntica. La capa epitaxial presenta el mismo espesor y se dopa igual que en un FET. Sin embargo, existe una importante diferencia: el material de partida es una oblea dopada Tipo P en lugar de Tipo N. La unión PN adicional, así creada, inyecta portadores (huecos) en la región epitaxial Tipo N reduciendo su resistividad y rebajando la caída de tensión en conducción

El techo de frecuencia se sitúa alrededor de los 75kHz, debido a que la corriente principal se controla con un transistor bipolar. En estos dispositivos sin embargo, se han conseguido tiempos de conmutación de 0,2 ms con muy bajas caídas de tensión, lo que les hace muy útiles en conmutaciones rápidas.

La facilidad de control, similar a la de un MOSFET, unida a sus pérdidas relativamente bajas, les convierten en la elección idónea para aplicaciones de control de motores conectados directamente a la red (hasta 480 V). Para tensiones de 400 a 1200 V, los IGBT ofrecen ventajas sustanciales frente a los transistores bipolares de potencia, por lo que están sustituyendo a éstos en un amplio campo de aplicaciones.

Actualmente, con la aparición de la 2ª generación de IGBTs, los fabricantes ofrecen una amplia gama de estos dispositivos, y se pueden elegir bien por su rapidez o bien por su caída de tensión en conducción; esto es muy interesante ya que permite optimizar la utilización de éstos dispositivos en función de las distintas aplicaciones. Se encuentran ya dispositivos capaces de soportar 1200 V y 400 A.