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What happen if I run a Tesla drive train at 200v? What will change? Max speed? Power output? What will happen in term of performance? What will decrease?
 

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What happen if I run a Tesla drive train at 200v? What will change? Max speed? Power output? What will happen in term of performance? What will decrease?
Nothing will change up to the speed at which more than 200 volts is required to produce full power; past that, power will be restricted. It won't be able to produce power at all at the usual maximum speed.
 

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What happen if I run a Tesla drive train at 200v? What will change? Max speed? Power output? What will happen in term of performance? What will decrease?
Nothing will change up to the speed at which more than 200 volts is required to produce full power; past that, power will be restricted. It won't be able to produce power at all at the usual maximum speed.

So basically it will have like a rpm limit? Roughly half of the speed it will give at 400v? I guess also want give the same kw? Meaning power output?

What to expect other than reduce top speed? What about torque and horsepower?

Thank you very much for the reply!!!
 

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Hi !

You will probably be able to have about half the power as you would at 400v.

You will be able to have full torque up to about 30-33mph (half of the 62mph).
After that the torque will fall.

You will be able to rev it to its top speed but not with the same torque as with 400v.

Best Regards
/Per
 

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So basically it will have like a rpm limit? Roughly half of the speed it will give at 400v? I guess also want give the same kw? Meaning power output?

What to expect other than reduce top speed? What about torque and horsepower?
Most of the voltage goes to overcoming back EMF, which is proportional to both current and motor speed. So half the voltage can maintain the same current (and so the same torque) to about half the speed.

The motor can still run faster than that, but with more limited current, and so more limited torque, and so less power (power = torque X speed).

You don't get to independently choose voltage and current. The controller applies voltage, current flows as a result, and the product of the two is power. How much voltage is required to push a specific current is dependent on motor speed, so for a given motor speed and power there is only one combination of current and voltage required.

Since performance charts are normally published only for maximum power output, many people don't seem to realize that a motor is driven with all of the available voltage very little of the time. Even when accelerating as hard as possible, voltage is limited to keep current within its limit at low speeds.
 

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It also depends on what you mean by Tesla drive train. If you mean, what happens if you give the OEM inverter 200v then NOTHING. I severely doubt that the OEM hardware will allow you to run the motor with only 200v on the HV DC bus. It would throw a fit because the voltage is so low. If you replaced the OEM inverter with something else then you might be able to set the lower voltage limit low enough to work.
 

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It also depends on what you mean by Tesla drive train. If you mean, what happens if you give the OEM inverter 200v then NOTHING. I severely doubt that the OEM hardware will allow you to run the motor with only 200v on the HV DC bus. It would throw a fit because the voltage is so low. If you replaced the OEM inverter with something else then you might be able to set the lower voltage limit low enough to work.
This is a good point. I was only considering the effect of available voltage to motor performance, but the controller/inverter does need to cooperate.
 
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