5SHY5055L0002 3BHE019719R0101 GVC736BE101 thyristor ABB

The provided text discusses the challenges in the current path design of high-power modules, particularly focusing on the limitations and considerations for achieving an ideal high current design.

Challenges in Current Path Design:

1. Modular Design Limitations:
   • The main current path needs to be split into two due to the modular design.
   • Wire bonds connect the chips to the substrate, and main terminals connect the substrate to the busbar.
2. Thermal Expansion Mismatch:
   • Mismatch in thermal expansion between silicon and other packaging materials requires designing flexible current leads to minimize stress on solder joints.
   • Flexibility in current leads results in long leads with a small cross-sectional area.
3. Compromise for Low Resistance:
   • High electrical resistance is a challenge due to the compromise between flexibility and maintaining low resistance.
   • Long leads with a small cross-sectional area lead to high electrical resistance.
4. Limitations in High Current Operation:
   • While a single terminal contact can have a rated current of up to 1,200 A, high ohmic heating in the terminal prevents sustained operation at these high currents without sufficient busbar cooling.
   • The maximum allowable temperature difference in the terminal is restricted by the packaging materials and busbar temperature limits.
5. Geometry Factor Importance:
   • An ideal high current design is crucial to maintain low electrical resistance between the busbar and the chip.
   • The geometry factor, defined as the ratio between the length and cross-sectional area of the current path, plays a key role.
6. Temperature Difference Limitations:
   • The maximum allowable temperature difference within the terminal is limited to around 50 K.
   • High resistance in the terminal connections can severely limit the maximum DC current of the module.
7. Geometry Factor Values:
   • The current terminals used today by ABB have a geometry factor of around 4,500 m-1.
   • The newer design aims for a lower geometry factor of 3,500 m-1, allowing for higher maximum DC currents (around 650 A).

Conclusion:

The text highlights the complexities and trade-offs involved in designing the current path for high-power modules, emphasizing the importance of achieving an ideal high current design to ensure efficient and reliable operation. If you have further questions or need additional information, feel free to ask.