In looking for a good motor I was pointed to this 3KW BLDC. I'm confident the motor will have more than enough power. I'm going to be very technical in my methods so I hope this thread will be helpful to those interested in utilizing this motor.
I estimate the cost of this project at approximately $2000
It is my opinion that the motor will need geared down quite a bit so I will be utilizing a custom built drive.
The Motor is Model# HPM3000
It is rated at 2/3 KW Continous and 6KW Peak.
The operating RPM is listed as 3000 to 5000 RPM.
You can find the complete specification online.
The first question to answer is how should the drive be configured.
Direct : Jackshaft or other means out using sprockets.
Geared: Using a configuration of gears and sprockets.
I have attached the datasheet for this motor to this post. It is like a dyno sheet for a gas engine.
After reviewing the data for the motor the question at hand can be answered mathematically.
If you find any errors in my calculations please advise so they can be corrected.
________________________________________________________
#1 Conversion of the tire rotations into MPH.
I'm going to skip through the math here but if you would like to know how this is calculated I will go through it.
Just ask.
The baseline I'm going to use is:
12.68 RPM of the tire = 1 Mph.
This is specifically for a 26" by 2.5" tire.
________________________________________________________
Calculation #2 " gear ratios "
This would be for example a 10 tooth sprocket on the motor and a 60 tooth sprocket on the wheel.
I know....we wouldn't do that, we would use a jackshaft and a smaller sprocket on the wheel.
I choose that example for simplicity of demonstrating drive ratio.
60 tooth sprocket divided by 10 tooth sprocket.
This is a 6:1 ratio.
The 10 tooth has to make 6 revolutions for the 60 tooth to make 1 revolution.
Ok that's the easy basics.
You should be able to calculate ratio and were using 12.68 wheel revs = 1Mph.
We also have the datasheet to use as a guideline for our design parameters.
I estimate the cost of this project at approximately $2000
It is my opinion that the motor will need geared down quite a bit so I will be utilizing a custom built drive.
The Motor is Model# HPM3000
It is rated at 2/3 KW Continous and 6KW Peak.
The operating RPM is listed as 3000 to 5000 RPM.
You can find the complete specification online.
The first question to answer is how should the drive be configured.
Direct : Jackshaft or other means out using sprockets.
Geared: Using a configuration of gears and sprockets.
I have attached the datasheet for this motor to this post. It is like a dyno sheet for a gas engine.
After reviewing the data for the motor the question at hand can be answered mathematically.
If you find any errors in my calculations please advise so they can be corrected.
________________________________________________________
#1 Conversion of the tire rotations into MPH.
I'm going to skip through the math here but if you would like to know how this is calculated I will go through it.
Just ask.
The baseline I'm going to use is:
12.68 RPM of the tire = 1 Mph.
This is specifically for a 26" by 2.5" tire.
________________________________________________________
Calculation #2 " gear ratios "
This would be for example a 10 tooth sprocket on the motor and a 60 tooth sprocket on the wheel.
I know....we wouldn't do that, we would use a jackshaft and a smaller sprocket on the wheel.
I choose that example for simplicity of demonstrating drive ratio.
60 tooth sprocket divided by 10 tooth sprocket.
This is a 6:1 ratio.
The 10 tooth has to make 6 revolutions for the 60 tooth to make 1 revolution.
Ok that's the easy basics.
You should be able to calculate ratio and were using 12.68 wheel revs = 1Mph.
We also have the datasheet to use as a guideline for our design parameters.
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