Vitesco Technologies, a provider of advanced drive technology and electrification solutions, has chosen GaN (Gallium Nitride) to enhance the power efficiency of its Gen5+ GaN Air DC/DC converters. The CoolGaN Transistors 650 V manufactured by Infineon Technologies AG greatly enhance the overall performance of the system, while simultaneously reducing system cost and improving user-friendliness. Vitesco has developed a new generation of DC/DC converters that have achieved exceptional power density (with an efficiency rating of over 96 percent) and have set new benchmarks for sustainability in power grids, power supply, and OBCs.
The benefits of GaN-based transistors in high-frequency switching applications are significant, but the most crucial advantage is the enhanced switching speed, which has been raised from 100 kHz to over 250 kHz. This allows for extremely low switching losses, especially in hard-switched half-bridges, while minimizing thermal and overall system losses. Furthermore, Infineon’s CoolGaN Transistors exhibit exceptional turn-on and turn-off speeds and are enclosed in a top-cooled TOLT packaging. The devices are cooled by air, which eliminates the requirement for liquid cooling and thereby decreases the overall expenses of the system.
The 650 V devices enhance power efficiency and density, allowing for an 800 V output. Furthermore, they possess a low ON-resistance (RDS(on)) of 50 mΩ, a high transient drain-to-source voltage of 850 V, a maximum drain current (IDS, max) of 30 A, and a maximum drain current (IDS, max) of 60 A.
Vitesco Technologies utilized GaN Transistors to develop their Gen5+ GaN Air DCDC converters, incorporating passive cooling to effectively lower the system’s total cost. The GaN devices facilitate streamlined converter design and mechanical integration. Consequently, the DCDC converters can be strategically placed in the vehicle, hence decreasing the burden on manufacturers. By utilizing GaN, the converters may be expanded to a power capacity of 3.6 kW and achieve a power density exceeding 4.2 kW/l.
The Gen5+ GaN Air DCDC converters provide an efficiency of over 96 percent and demonstrate enhanced thermal performance in comparison to the Gen5 Liquid-Cooled converters. Their output consists of two phases, delivering a continuous current of 248 A at a voltage of 14.5 V. The phases can be integrated to attain the utmost output power. However, it is also feasible to deactivate one phase when operating at less than full capacity and alternate the switching frequency between the two phases. Furthermore, by interchanging the input of two consecutive phases, the converters utilizing the CoolGaN power transistors with a voltage rating of 650 V can be employed to establish 800 V structures without surpassing the device’s maximum voltage blocking capacity. The converters utilize an isolated half-bridge topology including of a GaN-based half-bridge, a completely isolated transformer, and an active rectifier unit for each phase.