Power Electronics is a general term that refers to the technologic control of the flow of electrical energy. If you’re not familiar with the term, you’ve still probably heard of a few products that rely on the technology such as power converters, inverters, motor drives, or motor soft starters. We live in an energy-conscious age with ever-changing digital technology. Power electronic devices have become central to enabling technology in this era, opening up a whole new world of programmable control and system functionality.
As far as engineering systems are concerned, power electronic devices are incredibly efficient. The efficiency of a power switching device, for example, can be greater than 95%. If the engine in your car was 95% efficient (instead of around 35%...) at converting fuel to mechanical energy you could drive your car clear across the U.S. on a single tank of gas. While 95% efficiency is an impressive figure, it is significantly less than 100%. Alas, like most inefficiencies, that remaining 5% of energy input is converted into heat and needs somewhere to go.
A cooling solution that needs to manage only 5% of the total energy input into a device sounds like a pretty easy task, right? Well, it depends. In larger power electronics systems like power inverters for renewable energy systems, the total amount of energy going through the system can be several megawatts of power (that’s 1,000,000 Watts). While 5% is a small number on its own, 5% of a large number is still huge (50,000 Watts in this example).
So what is to be done with all of this wasted energy? The short answer is get rid of it. Heat and sensitive electronics seldom play nicely together and so all of that heat needs to get removed from the system and dissipated to the surrounding environment. How you do that depends on how much heat you need to get rid of. The figure below provides some examples of cooling technologies that ACT has utilized and developed for the Power Electronics market. Each technology has an applicable thermal power range in which it performs best and the solutions range from basic to more complex. So, before you tell your boss in the Monday morning meeting that you can double the output of your next product, give some consideration to which technology can help you deal with that that pesky 5% inefficiency.