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General high-speed discussion / Re: driving low pressure sodium lamp without 60Hz flicker
« on: February 09, 2018, 01:51:10 AM »
The ballast seems to use a valley-fill rectifier to improve the power factor without using an active pfc circuit:
https://en.wikipedia.org/wiki/Valley-fill_circuit
You could modify the circuit by replacing both capacitors with ones having a higher voltage rating (200V), short out D1+D2 and remove D3+D1.
This should reduce the ripple and thus the flicker significantly.
But this will also increase the average dc voltage and therefore the output power slightly.
https://en.wikipedia.org/wiki/Valley-fill_circuit
You could modify the circuit by replacing both capacitors with ones having a higher voltage rating (200V), short out D1+D2 and remove D3+D1.
This should reduce the ripple and thus the flicker significantly.
But this will also increase the average dc voltage and therefore the output power slightly.