I just built a solar powered R/C car as seen here and I would like to make the best of the motor and solar panel
I recently heard of Maximum Power Point Tracking devices used to keep the load seen by the solar panel at or below the "Maximum" so that the voltage will not drop and the total wattage is less.
I'll let some of the better gifted writters explain MPPT.
I do understand that if I exceed the Maximum Power Point load the total power is reduced. On my car if I give the motor hard throttle, sometimes the voltage drop is so great, the radio system and motor controller will shut down. To avoid this, I just geared the motor lower which affect top speed.
What I do not understand is do motors act differently with lower voltage and higher amps vs. higher voltage and lower amps and the total wattage is the same.
I will provide some information about my solar car:
Panel is 9.9V open circut, 3.6A dead short. My caluclated Maximum power point is 8.4V at 3amps or about 25watts. At dead short the voltage is 3V so the power is about 10W. The motor has 0.333ohm of resistance per phase and is rated for 5A continous current.
I just purchased the EasyMax for my solar car and when the device senses a higher load, it will convert my power into a lower voltage current with greater load. As the load lessens, the voltage is returned to normal. While I am waiting for the post man to come with the device I wanted to know if the device will really improve accelleration by providing more amps at a lower voltage compared to a higher voltage at lower amps. This situation really only occurs on standing starts or comming onto the throttle after a corner. If the device just prevents my motor from exceeding the MPP it is still worth it to me as I want to make the most of my panel.