To electrify vehicles and help achieve the decarbonization of society, it is necessary to continue to develop more efficient, compact and lightweight electric powertrains. Although silicon carbide (SiC) power devices have received much attention as mission-critical components, achieving low losses in small sizes has proven challenging.
ROHM solves these problems in powertrains with the TRCDRIVE package. Supporting power up to 300 kW, the TRCDRIVE kit features high power density and unique terminal configurations, helping to solve key traction inverter challenges related to miniaturization, higher efficiency and less labor required for design.
The TRCDRIVE kit reduces switching losses by optimizing the internal layout to achieve a low inductance of 5.7 nH. Additionally, the fourth generation low on-resistance SiC MOSFETs provide a current density of 19.1 A rms/cm2 (BST780D12P4A163) and an output current of over 600 A rms for 750 V ratings (e.g. BST740D08P4A154) and 1200 V. B (for example, BST780D12P4A163). )model.
The TRCDRIVE package will include 12 models with different body sizes (small/large) and mounting methods (TIM: radiator/silver sinter). In addition, ROHM is developing a 6-in-1 product with a built-in heatsink, which is expected to facilitate the rapid design of traction inverters and the release of models tailored to different design characteristics.
The company has launched four new models as part of the TRCDRIVE Pack series, focused on electric vehicle traction inverters using two-in-one molded SiC modules (two BSTxxxD08P4A1x4 for 750 V and two BSTxxxD12P4A1x1 for 1200 V). The electric vehicle’s traction motor is driven by three-phase alternating current with a phase shift of 120 degrees.
The traction inverter converts the DC power provided by the battery into three-phase AC power. To convert DC power to three-phase AC power, one high-side MOSFET and one low-side MOSFET are required to switch each phase. The 2-in-1 configuration combines these two MOSFETs into one module (note that the x-in-1 drive configuration in the xEV package is different from the x-in-1 configuration in the traction inverter).
Molded SiC modules are a trademark of ROHM and are specially designed for traction inverter drives. The TRCDRIVE package uses a unique design to maximize heat dissipation area and thereby reduce size. The battery pack is said to have a smaller one-way heat dissipation design through a proprietary molded module design, resulting in heat dissipation efficiency comparable to competing products.
In addition, a 4th generation ROHM SiC MOSFET is integrated. The power density is said to be 1.5 times higher than conventional molded SiC modules, and this also makes a huge contribution to the miniaturization of xEV inverters.
The module features press-fit control terminals that can be easily connected by simply pressing the top of the gate driver board, significantly reducing installation time. Additionally, by maximizing the current path and using a dual-layer busbar structure, the main wiring achieves low inductance (5.7 nH), which helps reduce switching losses.
While the modules are being developed, Rohm has created a mass production system similar to discrete products that can increase production capacity by 30 times over traditional packaged SiC modules, according to the company.
ROHM is committed to providing application-level support, including the use of proprietary engine testing equipment. Various support materials, such as simulation and thermal design, are also available to quickly evaluate and implement TRCDRIVE products.
Two evaluation kits (EVKs) are available: one for two-pulse testing and the other for three-phase full bridge testing, allowing evaluation under conditions similar to those of real inverter circuits. For example, EVK’s dual-pulse testing features pre-wired external screw terminals, eliminating the need for additional terminal soldering. No special capacitor is required and the evaluation can be performed under a variety of standard conditions.
ROHM develops SiC technology in-house, from wafer fabrication and fabrication processes to packaging and quality control methods. At the same time, to strengthen its position as a SiC supplier, ROHM noted that it has created an integrated production system throughout the entire production process.
Post time: Jul-08-2024