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Hagerty video
- Thread starter TEG
- Start date
Maybe some mistakes with the prototype 2-speed transmission manufacturer history...
Otherwise a nice bit of history and keeping the Roadster excitement alive.
The title is a bit "click bait"... You can watch it to understand why that one Roadster isn't worth $35 million. (Well, maybe someday!)
Otherwise a nice bit of history and keeping the Roadster excitement alive.
The title is a bit "click bait"... You can watch it to understand why that one Roadster isn't worth $35 million. (Well, maybe someday!)
I agree….his take on this is simplistic. This is a fascinating subject to me…..I see this as an application or gear in problem…..why they started out with a two speed gearbox to complicate things is beyond me because the VFD technology to use a single speed motor and drive was quite mature at the time.
I do know the AC Propulsion drives were fairly simple thyristor freq drives but did those cars that started with two speed gearboxes have the PEM from the Taiwanese manufacturer in them or an AC Propulsion drive? The early cars must have been more than a gearbox change….the motor and VFD must have been changed out as well. Going to an IGBT drive to me would have meant realizing Vector Drive technology was key to getting the torque they needed at zero speed.
I do know the AC Propulsion drives were fairly simple thyristor freq drives but did those cars that started with two speed gearboxes have the PEM from the Taiwanese manufacturer in them or an AC Propulsion drive? The early cars must have been more than a gearbox change….the motor and VFD must have been changed out as well. Going to an IGBT drive to me would have meant realizing Vector Drive technology was key to getting the torque they needed at zero speed.
From what I recollect, Tesla started out trying to make a licensed, modified version of an ACP style analog PEM. It didn't have the amps/torque at the low end to get their advertised 0-60 without a dual speed gearbox. So that was the initial intended architecture/design. The failures of the shifting were about to ruin the company before they could even get started and JB's team started a "hail Mary" side project to see if they could make a digital PEM with new generation IGBTs (that got on the market just in time) and they were unsure if they could even make it work. From what I understand, Drew Baglino (who is now the new CTO), was instrumental in writing some of the early motor controller firmware that allowed them to create a new "Digital PEM" with enough low speed amps to get the torque they needed for 0-60 in 4 seconds without shifting.
The first dozen or so customer roadsters were delivered with the old 2-speed gearbox locked in 2nd gear, and 0-60 in maybe 6 seconds.
Tesla basically recalled all of those cars and swapped in the finalized "1.5" gearbox after customer deliveries had already started. They had run out of time and did some difficult "tapdance" to get some cars delivered before they were really ready.
One side effect of switching to "one speed gearbox" may have been a slight reduction of possible top speed to get the 0-60 they promised. But I guess customers accepted the 125MPH top speed, but were not willing to accept 0-60 > 4s.
The first dozen or so customer roadsters were delivered with the old 2-speed gearbox locked in 2nd gear, and 0-60 in maybe 6 seconds.
Tesla basically recalled all of those cars and swapped in the finalized "1.5" gearbox after customer deliveries had already started. They had run out of time and did some difficult "tapdance" to get some cars delivered before they were really ready.
One side effect of switching to "one speed gearbox" may have been a slight reduction of possible top speed to get the 0-60 they promised. But I guess customers accepted the 125MPH top speed, but were not willing to accept 0-60 > 4s.
