Experiment - 741 OpAmp On Primary 10/25/07

Submitted proposal for wireless charger.

Boost Converter for secondary side?

DC-DC converter to increase voltage. Maybe do this instead of increasing primary side voltage.

boost converter schematic source: http://www.daycounter.com/LabBook/BoostConverter/Boost-Converter-Equations.phtml

Experiment 10/25/07 – Op Amp used on primary side.

Note: Op Amp rectification not likely since only power source on secondary is the secondary coil itself, unless secondary voltage is increased to 18V+.

Op Amp on primary side resulted in approximately 2Vp-p on secondary.

Equipment:

LM741CN
2 X 10Kohm Resistors
Diode (unknown spec)
Input for V+: 15VAC @ 10 kHz
Measured Inductance of coils: approx. 0.007mH
Theoretical Formula for this coil (flat spiral coil):



Approximate values used:

Coil mean radius (r) = .5 inch = 0.0127 meter
wire coil number of turns (N) = 10
Coil depth (d) = .1 inch = 0.00254 meter

Source: http://www.ajdesigner.com/phpinductor/inductor_equation_n.php

Did not measure voltage at primary coil, oops.

Coils: Both primary and secondary were loosely wound coils made from straight lengths of wire (approx 4 inches) wound to approx. 1 inch diameter.

Conclusion: At this secondary voltage level, a rectifier diode will operate.