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If you wish to edit this spreadsheet you can make your own copy by selecting File -> Make a copy. It will then appear in your own Google Drive account.
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How to use this document:
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1. Measure the no power draw and speed of your motor. See this link as an example: https://www.radiocontrolinfo.com/brushless-motor-efficiency/brushless-motor-no-load-current/
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2. Enter the values in the grey boxes in the table below
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3. Compare the estimated switching losses and motor power draw from the fitting to the estimated values in the motor loss model described in this post https://things-in-motion.blogspot.com
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For information about how the fitting is applied in Google Sheets see this document: https://www.statology.org/linear-regression-google-sheets
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The values below are for a Turnigy Aerodrive SK3 - 5055-280KV Brushless Outrunner Motor https://hobbyking.com/en_us/turnigy-aerodrive-sk3-5055-280kv-brushless-outrunner-motor.html?___store=en_us
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Motor SpeedMeasured no-load power drawEstimated switching lossesEstimated Motor Core lossFitting parameters
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RPMWWW
Fitting function used y = (a * x^2) + (b * x) + c
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abc
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07.183986.28558454500.00000058008136360.0045936572426.285584545
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100010.688366.2855845455.173738606
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200017.171466.28558454511.50763994
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300025.056326.28558454519.001704
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400034.167716.28558454527.65593079
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500044.330416.28558454537.4703203
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600054.843556.28558454548.44487255
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700066.583236.28558454560.57958752
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800080.775976.28558454573.87446521
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900094.092626.28558454588.32950564
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100006.285584545103.9447088
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110006.285584545120.7200747
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