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Introduction

This is the second test in this series. For more details, see test 1.

This time we will test the motor with aluminum wire coils. This material has a slightly different characteristic from copper, with higher electrical resistance and being lighter.

Test 2 - Circuit with a single electronic switch (MOSFET)

The circuit used is the same as in test 1.

Test environment

The test environment is composed of the motor and a 30cm diameter propeller.

Development board

The development board contains:

1. Single switch circuit.
2. DC-DC Step Up for testing at different power levels (maximum 96.5VDC).
3. Power control (voltage variation) applied to the motor.

Control circuit diagram

The figure below shows the control circuit. The switching sensor can be an optical sensor or a hall sensor. For this test, we will use an optical sensor.

The aluminum coil motor

Electrical characteristics:

• Resistance (Ohm): 158
• Inductance (mH): 130
• Amount of copper used in the motor (Kg): 0.120
• Wire gauge (AWG): 28

This motor was designed to work with voltages between 60 and 160VDC.

The motor is approximately 30% lighter than the other version with copper coils.

Results

The test was executed from start to finish, meaning the motor was running continuously for 50 minutes.

Each result row was obtained with the motor running for 10 minutes.

Power x temperature

The ambient temperature was constant, around 24.3°C.

Power x speed

The rows below show the performance of the motor with this topology.

Final considerations

As shown in test 1, this topology is reliable.

Comparing the power comsumption, aluminum was slightly superior to copper:

More tests at higher power levels and for longer periods of time should be more conclusive.

Questions?

If you have any questions, feel free to contact me.