Ferrite Core Transformer and SPWM Inverter

Hello All,


I am building a Pure sinewave Inverter.Now, when I connect my dc-dc converter to the drains of my full bridge inverter (SPWM section) my ferrite core tranformer begins to make a sound and then after a little while I see smoke coming from it. What could be the problem? I was wondering if it could be the LC filter at the output of the dc-dc converter maybe it needs to filter better to smooth the dc voltage to the inverter? not sure though.

The led that I placed across the drain of one of the low side Mosfets lights up but I hear the noise from the transformer and then I see smoke from it then I switch off the circuit otherwise when not connected to the full-bridge inverter it works fine giving 180Vdc with no sound from the Ferrite core transfromer.

Please help!!!!

Does you bridge draw an excessive current? It could be that the core has excessive losses st you PWM switching frequency. Could be there is overlap on on bridge switching devices - do they get hot. Have you tried using some other load then your transformer primary. Have you a shorted turn in the transformer (see excessive current).
Frank