The Challenges of High Power in RF Applications Webinar

Summary

This presentation will tackle the nuances of high-power applications involving coaxial cable assemblies. Different types of power and their impact on cable integrity will be discussed along with case studies that show how coaxial design can make the difference between safe operation or potentially dangerous operating conditions.

Watch the video or read the session notes below.

Session Notes

How Different Types of Power Affect Coaxial Cable Performance

When it comes to high power issues related to coaxial cable assemblies, it’s important to understand how power is classified and how it is used in real-world settings:

• High current: Found in industrial applications like semiconductors
• High voltage: Found in energy storage of high power, fractional duty cycle applications
• High power: Found in aerospace applications such as electronic warfare

High Current

Generally, current carrying capability is directly proportional to the crossed area of conductors. Therefore, the larger the conductor, the lower the resistance, the higher the current carrying capability. This drives the need for large cables and connectors.

Similar to a water pipe, more current can efficiently be produced through a larger conductor, which can be accomplished by simplifying the conductor design. A conductor with fewer piece parts and contact points provides a more robust design.

High current can also lead to sources of localized hotspots and weak spots in the design, and there are specific techniques and design features that can mitigate that issue.

High Voltage

High voltage power has arcs and flash-overs, essentially miniature versions of lightning bolts. Like lightning bolts—where huge amounts of charge are built up between the clouds and the surface of the Earth—voltage can increase between a generator and the ground to the point that it can no longer withstand the voltage and is released.

In this application, it is not so much about the size of the conductors but the capability to isolate and insulate one conductor from the other, or the cloud from the ground. This can be achieved by putting a high dielectric strength insulator between the conductors.

High Power

High power is thermal-related, continuous wave (CW) energy. The issue here isn’t voltage or current; it is the heat that is generated. When power is pumped into a cable assembly, some loss or inefficiencies occur. That lost power must be dissipated.

The issues are generally thermal and heat buildup, and the cable’s ability to transfer heat from its internal environment to the external environment. One mitigation technique is to increase the surface area of the component to radiate heat.

Conclusion

When failure modes happen, they can be dramatically catastrophic. Therefore, it is important to choose the right components, ensure that those components are designed to mate together, and that the cable and connector interface are designed to work together.

It is critical to use a connector that’s designed specifically for a cable and for a specific power application. They should also be installed and assembled by people who are experienced and understand the issues.

Q&A

Following are the questions that were asked by the audience:

• What is the most important component when selecting an assembly for high power?
• Does electrical performance change as cables get hot? What can we do to control or mitigate that?

To learn the answers and hear the full detail provided in the webinar, register now!