# Initial Calculations - Strange figures

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Hi Team

Done some preliminary calculations to find values for PMAC Electric motor which can go with Curtis 1234SE 5471.

I am going with two independent rear wheel motor setup, for a small 1500Kg Hatchback, doe values like 15KW. [email protected] per motor make any sense?

I am finding hard to find a motor for this setup

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#### brian_

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Done some preliminary calculations to find values for PMAC Electric motor which can go with Curtis 1234SE 5471.

I am going with two independent rear wheel motor setup, for a small 1500Kg Hatchback, doe values like 15KW. [email protected] per motor make any sense?
The values in the spreadsheet look generally reasonable, except for the completely nonsensical torque value. I can only guess that the cell in the spreadsheet which calculates torque has been accidentally modified.

torque = power / rotational speed
torque [Nm] = power [W] / (speed [rev/second] * 2 * pi)
For 15 kW @ 1500 RPM, torque is about 100 Nm, not 2 Nm.

I'll also note that the spreadsheet calculates how much power is required to keep the vehicle moving at 120 km/h... but allows no extra to accelerate so it can get there.

#### Vinz

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The values in the spreadsheet look generally reasonable, except for the completely nonsensical torque value. I can only guess that the cell in the spreadsheet which calculates torque has been accidentally modified.

torque = power / rotational speed
torque [Nm] = power [W] / (speed [rev/second] * 2 * pi)
For 15 kW @ 1500 RPM, torque is about 100 Nm, not 2 Nm.

I'll also note that the spreadsheet calculates how much power is required to keep the vehicle moving at 120 km/h... but allows no extra to accelerate so it can get there.
Thanks Brian, I have corrected the mistake and have modified it accordingly

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