Apr 15, 2015 #1 F franticEB Full Member level 3 Joined May 10, 2010 Messages 152 Helped 1 Reputation 2 Reaction score 2 Trophy points 1,298 Activity points 2,540 Hi, i've found an old inverter schematic with an inductor and resistor on high mosfets' drain as figure below I try to reproduce it without RL circuit and mosfets become hot (80° over ambient) for conduction and switching losses as in my calculations. Then i tried to mount the RL circuit and temperature rise on mosfets was very low (30° over ambient). I did not understand how this circuit (RL red circle in figure) acts and how you can calculate component values. Could you help me? I don't found anything (tutorial or application note on this subject). This RL also allow me to increase switching frequency... Parameters: Fswitching=50Khz Pout=150Wrms
Hi, i've found an old inverter schematic with an inductor and resistor on high mosfets' drain as figure below I try to reproduce it without RL circuit and mosfets become hot (80° over ambient) for conduction and switching losses as in my calculations. Then i tried to mount the RL circuit and temperature rise on mosfets was very low (30° over ambient). I did not understand how this circuit (RL red circle in figure) acts and how you can calculate component values. Could you help me? I don't found anything (tutorial or application note on this subject). This RL also allow me to increase switching frequency... Parameters: Fswitching=50Khz Pout=150Wrms
Apr 15, 2015 #2 KlausST Advanced Member level 7 Joined Apr 17, 2014 Messages 25,947 Helped 4,910 Reputation 9,843 Reaction score 5,726 Trophy points 1,393 Activity points 174,110 Hi, Maybe the RL prevents from high current during cross conducting of two fets. But i don't know... Klaus
Hi, Maybe the RL prevents from high current during cross conducting of two fets. But i don't know... Klaus
Apr 16, 2015 #3 I ishtifar Newbie level 1 Joined Apr 16, 2015 Messages 1 Helped 0 Reputation 0 Reaction score 0 Trophy points 1 Activity points 5 Hello franticEB, Z(L) = jwL For DC circuit, w=0 and so the resistor at the drain is actually shorted. Which is why the there is no power dissipation through the resistor and it stays cooler. Thanks.
Hello franticEB, Z(L) = jwL For DC circuit, w=0 and so the resistor at the drain is actually shorted. Which is why the there is no power dissipation through the resistor and it stays cooler. Thanks.