Posted to YouTube today. Enjoy!
As I understood it the extra modules are to accommodate the need for less error in communication, because as horsepower increases the fluctuations in HP are more noticeable if you don’t have more processing precision. This whole video is awesome, he explains wave mechanics very well. I liked that he pointed out the same principles are used in digital audio, where you’re putting multiple rapid digital samples in sequence to replicate an analog sine wave (aka sampling rate in digital audio). The challenge to overcome here is the Nyquist limit, as you will get an alias frequency of whatever half the sampling rate is. This is not a problem in digital audio above 44.1khz as your ear can’t perceive 22khz which would be the alias frequency. However, in the extremely high frequencies of the triphasic sine wave he mentions needed to turn the permanent magnet motors, if you had an alias frequency at half of whatever the desired frequency was, you’d have some serious fluctuations in power output. I’m not a mechanical engineer so I have no idea how Lucid would compensate for this, or if it’s even necessary to, but I’d assume they’d put some sort of filter in to block anything at or below the Nyquist frequency.He mentions that the GT front inverter has 3 silicon carbide modules while the GTP has 6. Is that for increased efficiency? Fewer chips, less energy passing through?
He tells us that the stator inductance is used as a filter since inductors are very good at smoothing current. A very nice design by Lucid to tune the inverter and motor together.I’m not a mechanical engineer so I have no idea how Lucid would compensate for this, or if it’s even necessary to, but I’d assume they’d put some sort of filter in to block anything at or below the Nyquist frequency.
Ah I didn’t get that part, make sense.He tells us that the stator inductance is used as a filter since inductors are very good at smoothing current. A very nice design by Lucid to tune the inverter and motor together.
Since the GT's front motor has lower power output than the GTP's, current levels are correspondingly lower. One set of SiC switches can handle the GT motor's maximum current without overheating. Two sets of switches are needed to handle the GTP's higher motor current without overheating.He mentions that the GT front inverter has 3 silicon carbide modules while the GTP has 6. Is that for increased efficiency? Fewer chips, less energy passing through?