WetEV wrote:
The motor is 6 phase. This means there are six sets of coils that make a magnetic field to push the rotor around, connected to the 6 phases output from the inverter.
eh.... I might have to disagree on the details of this, and sometimes stray a tad off topic, sorry, and I know you're knowledgeable, so a lot of this will be "no shit sherlock" to you, but for the benefit of others, I'll try to make some clever analogies.
The motor is three phase, the inverter is 3 phase, there are three AC cables running between these two components. This is set in stone.
The motor itself is an 8 pole motor, which is related to the number of times the coils and magnets are repeated around the rotor and stator.
More poles = slower speed at any given frequency, a lot like teeth on a gear. Frequency means how many teeth you can pass per second, and phases are how many intermediate steps there are in the passing of a single tooth..more or less. More phases = smoother. Smoother is better, but once you start moving at high speed, it stops mattering and three is plenty, and as we can clearly see (by driving the car) that even at extremely slow speeds, three phase is plenty smooth because the coils aren't driven at full or zero power, but rather in a set of three, synchronized sine waves offset by 120º. Some low speed motors, like stepper motors, are usually considered 2 phase, and definitely benefit from more phases. There are plenty of 3 and 5 phase steppers out there, and they're slick and fancy and expensive and overkill for most applications. 2 is usually fine, especially when the inverters (or drives in their cases) put out cute little sine waves.
Now on to that inverter. So say the internets, the inverter has a six step control scheme, which looks like it's just a way of them diddling the current and waveform (those sine waves again) to be more efficient at different speeds. Kinda like valve / ignition timing etc. But that number isn't phases. Again, going back to stepper motors, often, at low speeds they drive them with sine waves, but as the speed increases, the drive current can morph into a square wave to give more torque at higher speeds. Here's the other thing about inverters... Adding more phases means adding more transistors (IGBTs or whatever) which are probably the most expensive single components in there, and you need six for a bare minimum 3-phase inverter. And more for more phases.