How to rectify my AC Voltage?

I am working on a piezoelectric generator harvestor.I have connected some stack together and the voltage comes to about 50V.However when I connect a diode rectifier both the ac input and DC output reduce to a very very small value.What could be the issue?

Answer 1

[Joel Van Sickel]

it's possible your load is too large (resistance too small) and the piezoelectric device isn't powerful enough to charge it. You are essentially shorting out the terminals. It has to be able to bias the diodes and drive current through the capacitor/load.