Fuji Electric Review
Vol.68-No.4,2022
Power Semiconductors Contributing to Mobility and Energy Management
Power Semiconductors Contributing to Mobility and Energy Management
As the global trend of striving to achieve carbon neutrality is accelerating, which is aimed at solving climate change, Fuji Electric has established its Environmental Vision 2050 to determine the direction of the Company’s long term environmental activities. It has set the Fiscal 2030 Goals toward reaching the Vision, one of which is the“ contributions to CO2 emissions reductions in society through our products.” Among the essential factors to achieve the goal are mobility electrification and stable, efficient use of energy through the efficiency enhancement of power electronics equipment, and semiconductors from Fuji Electric play an important role in such improvements. This special issue presents the latest technologies and products in Fuji Electrics’ power semiconductors.
LORENZ, Leo
Mobility and Energy Management Current Status and Future Outlook
ONISHI, Yasuhiko; MIYASAKA, Tadashi; IKAWA, Osamu
Decarbonization efforts are accelerating globally in order to achieve carbon neutrality, and Japan and other countries around the world have set specific targets for reductions in greenhouse gas emissions. At Fuji Electric, our management philosophy is to "contribute to prosperity," "encourage creativity," and "seek harmony with the environment," and one of our management policies is to contribute to the creation of a sustainable society through our energy and environment businesses. We have established our Environmental Vision 2050, which is aimed at achieving a "decarbonized society," "recycling-oriented society," and "society in harmony with nature" through the spread and expansion of innovative clean energy technologies and energy-saving products. Achieving a decarbonized society, in particular, is depend on progress in the electrification of automobiles and the efficient use of electric energy, for which power electronics equipment is indispensable. As key devices in power electronics equipment, power semiconductors are becoming increasingly promising. This paper describes the current status and future outlook of power semiconductors and technologies.
SATO, Yushi; ADACHI, Shinichiro; HIGASHI, Nobuhiro
In the automotive field, electrified vehicles are expected as a measure of reducing greenhouse gas emissions. Their power modules in the inverter are required to have a higher power density, that is, small, thin and high output. To meet these market demands, Fuji Electric has developed the “M677,” an industry-leading ultra-compact IGBT module for xEVs. We have improved the short-circuit capacity of this small, thin IGBT by bonding the lead frame wiring on the flat surface of the chip to reduce the stress per unit volume that has increased with the growth of the power density. In addition, the solder joints have sufficient resistance to the electromigration lifetime to meet the market needs.
TAKAKU, Taku; TAKASAKI, Aiko; OKUMURA, Keiji
Fuji Electric has developed 1,200-V All-SiC modules, which are expected to significantly reduce dissipation losses of power converters compared with silicon (Si) power semiconductors. We have newly developed an All-SiC module equipped with a 1,700-V SiC-MOSFET using the 2nd-generation trench gate structure. It is designed for high-voltage power converters used in motor drives, renewable energy and traction. The All-SiC modules reduce dissipation losses in the power converters by 68% compared with Si-IGBT modules with the same power ratings. It is expected to increase the density and miniaturization of the power conversion systems.
KUROSAWA, Eiji; JOZUKA, Naohiko; KARAMOTO, Yuki
In order to meet the demand for further miniaturization and higher reliability in power conversion systems, Fuji Electric has developed a line-up of the 7th-generation IGBT-IPMs that is equipped with RC-IGBT chips and uses the new compact “P639” package, the footprint of which is 27% smaller than that of “P629” package used for 6thgeneration IGBT-IPMs. By applying the 7th-generation chip technology and new control technology for driving the IGBT, the new compact P639 has reduced the power dissipation during continuous operation by 7%. Moreover, it applies the 7th-generation packaging technology to achieve high-temperature operation at 150°C.
IKURA, Yoshihiro; HARADA, Yuichi; SEKINO, Yusuke
The railways, including high-speed rails, use IGBT modules for drive motors. It is essential for IGBT modules to reduce power loss, as they directly contribute to CO2 reduction. To meet this demand, Fuji Electric has developed a 3.3-kV SiC hybrid module that combines the latest generation “X Series” IGBTs and SiC-SBDs. Using a finer surface structure and a thinner drift layer, the X Series IGBT chip has reduced the collector-emitter saturation voltage by 1.0 V, compared with a previous generation. In addition, by combining it with a SiC-SBD, the hybrid module has achieved significant performance improvements with a turn-on loss reduction of 51% and reverse recovery loss reduction of 98%.
MATSUMOTO, Shinji; YAMANE, Hiroki; MIYAGI, Kodai
The recent electronic equipment market has increasingly seen advances in energy. This trend has increased the demand for switching power supplies for electronic equipment with high efficiency in power conversion at light loads, high voltage AC input, and compactness. Fuji Electric has thus developed the “FA8C00 Series” 7th-generation PWM power supply control ICs. Minimum output pulse width is selectable for optimal MOSFET gate drive, improving power conversion efficiency at light loads. The maximum applied voltage at the high voltage AC input terminals has increased from 650 V to 710 V. Furthermore, clamping the IC output voltage eliminates the need for an external regulator circuit, reducing the number of components.
IWAMOTO, Motomitsu; TOYODA, Yoshiaki; KATAKURA, Hideaki
Electronic components installed in an automobile have recently increased in number and are therefore being required to be mounted with high density on the electronic control unit (ECU) board. They are also required to be miniaturized and integrated. Fuji Electric has therefore been studying the development of a next-generation intelligent power switch that integrates current drive devices, current-sensing amplifier, and a current detection shunt resistor into a single chip. Integrating a shunt resistor into the chip requires an amplifier with enhanced accuracy. We have thus developed a highly accurate auto-zero amplifier technology that automatically corrects output errors. This amplifier helps reduce the ECU board footprint while maintaining the same current detection accuracy as conventional products.
BABA, Masakazu; TAWARA, Takeshi; TAKENAKA, Kensuke
When the body diode of a SiC-MOSFET is forward biased, characteristic degradation occurs as on-voltage increases with stacking faults expanding within the drift layer. To avoid the issue, integrating a trench SBD into a conventional SiC trench gate MOSFET will suppress a body diode current under forward bias without the need for increased chip size. This structure has increased the current density at which characteristic degradation occurs by approximately four times compared with conventional SiC trench gate MOSFETs. Without using external SBDs, this technology is expected to reduce the size and weight of products and reduce characteristic degradation, improving long-term reliability.
Arm
In switching circuits such as inverters, the parts that are made up of switches and diodes are called arms. As shown in Fig. 1, the circuit that supplies the load with an electric current from the power source is the upper arm. The circuit that draws electric current from the load to the power source is the lower arm.