New Industry Products

Infineon Releases Power Modules Designed for HEV Motor Drive Systems

October 17, 2006 by Jeff Shepard

Infineon Technologies AG introduced the first two members of its new family of electronic power modules designed for hybrid electric vehicle (HEV) motor drive systems. Based on Infineon's power semiconductors and a system-level design approach, the new HybridPACK1 and HybridPACK2 power modules are claimed to reduce the cost and complexity of HEV inverter system design by using up to 30% less semiconductor area to achieve the required power rating, and to reduce electrical power losses by 20% – enabling simpler cooling systems.

Designed for use in "mild" HEV vehicles, the Infineon HybridPACK1 power module contains all power semiconductors for the inverter and an NTC (Negative Temperature Coefficient) resistor for temperature measurement thus resulting in 30% less semiconductor area. The module is based on the combination of Infineon's Trench FieldStop IGBT (Insulated Gate Bipolar Transistor) and Emcon diode technology. For mild hybrid inverter applications, the flat copper base-plate combined with high-performance ceramic substrate and Infineon's enhanced wire-bonding process improves lifespan related to thermal cycling by a factor of 3 and lifespan related to power cycling reliability by a factor of 2. The base-plate measures only 7cm x 13.5cm. A mild hybrid car with an integrated starter/ generator can generate energy when braking ("regenerative braking") and can provide additional power for a few seconds only, for example for driveaway or overtaking.

For applications in full hybrids, HybridPACK2 offers a small footprint of only 9.2 cm x 20.2 cm for a 800A/600V six-pack module. The pin-finned Aluminum Silicon Carbide (AlSiC) base plate in HybridPACK2 not only enhances thermal performance, but also increases reliability. The full hybrid engine provides energy for mid-distance driving, for example for city traffic.

Unlike many power electronic applications, the design of HEV modules requires tight coupling of subsystems in order to achieve optimal system performance for a given cost. While the overall power system architecture and the type of hybrid system design (micro, mild or full hybrid) determine the overall fuel savings compared to an equivalent conventional power train, the power electronics play a significant role in ensuring efficiency, reliability and cost-effectiveness. With its wide portfolio of products including microcontrollers, power devices and sensors, Infineon is well-positioned to analyze HEV inverters from system perspective and provide a cost-effective solution while optimizing the performance. Compared to a combustion engine industry experts expect a micro hybrid car to save up to 5 to 10% of fuel, a mild hybrid car with its regenerative braking and boost functionality about 15 to 35% of fuel, and a full hybrid car up to 40 to 60% of fuel.

The Infineon IGBT technology provides several advantages for applications in HEV power systems. The Trench Fieldstop process yields lower conduction losses and reduced switching losses, with the combined effect of achieving smaller size of up to 30% for equivalent output performance compared to alternatives. Infineon IGBTs can operate at temperatures of up to 175°C, which makes cooling easier.