A UK-based company Ricardo has announced to develop Aluminum winding motor for lightweight EV application. This is an interesting move as normally most electrical machines are made with copper winding. Only in the case of the Induction motor rotor, the conductive bar is made with Aluminum. So let’s try to analyze why Ricardo decided to go with Aluminum instead of Copper. There are 5 important points that may influence Ricardo (and the 5th one is my personal favorite, so please don’t skip):
Pic Credit: Ricardo
1. Aluminum is lighter than copper, whereas the conductivity of Aluminum is almost 30% lower. So basically this translates what is the objective of the design: If the mass of the motor is your headache then Aluminum, if the volume is your headache then Copper.
2. In modern drive cycle, and high power density machine, supply frequency are quite high which means that the AC loss of Copper winding is higher than Aluminum. So even the DC loss in Aluminum is higher (because of higher resistance), the total power loss stays on par with Copper as Copper has a higher skin effect.
3. The thermal capacity of Aluminum is bigger than Copper which basically means with Aluminum winding you have better overloading capacity.
4. Aluminum is widely available, unlike Copper whose mining has recently drawn a lot of criticism lately. Also, this means Aluminum is cheaper. And who can ignore cost-effectiveness in modern business?
5. The most interesting environmental aspect of the modern electric motor is the recyclability and its footprint on the circular economy. Aluminum RECYCLING with Steel is much EASIER than recycling Copper with Steel. As a matter of fact, copper severely contaminates the recycling process, and literally one needs to dismantle it with different processes which makes it a bit unsuitable for easy recycling.
Please let me know what you think. Can Aluminum come as a viable alternative to Copper with its higher SUSTAINABILITY quotient? Please give your valuable comments and discuss.
