Joined
·
265 Posts
We did a “toy model” simulation for the performance of the GM Volt published earlier in this Forum under Engineering. This simulation was open ended in the sense that there is no “dynamometer” data to compare to the results. Tesla, however, has published data curves on their motor performance for the early version (Max Torque = 210 ft lbf) of their EV. (See http://www.teslamotors.com/performance/acceleration_and_torque.php)
We have attached Tesla simulation results for their Power Train 1.5 model (Max Torque = 280 ft lbf). This is for fixed gearing and not a CVT. We see excellent agreement between these simulation and data curves. The peak power occurs at 8400 RPM. (Note the Tesla site shows power in kW, we express it in the more familiar dimension of hp, i.e. hp/kW = 0.76.) The simulation shows 0-60mph in 4.9 sec, top speed of 130 mph, and single charge range @55 mph of 220 miles. That 220 mile range comes at the cost of lugging around 3.3x of both the weight (1000 lbs) and cost of the Volt’s batteries. E-REV is the way to go until weight and cost comes down.
The attachment is the Tesla simulation model and assumptions.
The primary motivation for doing this is to validate the earlier Volt simulation. Tesla data shows torque as falling off linearly. For the Volt we have no detailed Torque decay dynamometer data, therefore we just assume that torque falls off with constant power.
It's always a thrill to discover that the real world data agrees with the laws of the universe.
We have attached Tesla simulation results for their Power Train 1.5 model (Max Torque = 280 ft lbf). This is for fixed gearing and not a CVT. We see excellent agreement between these simulation and data curves. The peak power occurs at 8400 RPM. (Note the Tesla site shows power in kW, we express it in the more familiar dimension of hp, i.e. hp/kW = 0.76.) The simulation shows 0-60mph in 4.9 sec, top speed of 130 mph, and single charge range @55 mph of 220 miles. That 220 mile range comes at the cost of lugging around 3.3x of both the weight (1000 lbs) and cost of the Volt’s batteries. E-REV is the way to go until weight and cost comes down.
The attachment is the Tesla simulation model and assumptions.
The primary motivation for doing this is to validate the earlier Volt simulation. Tesla data shows torque as falling off linearly. For the Volt we have no detailed Torque decay dynamometer data, therefore we just assume that torque falls off with constant power.
It's always a thrill to discover that the real world data agrees with the laws of the universe.
