I need some help:
A friend has a Meanwell switch-moded power supply (type is actually unknown to me). It is a Meanwell 24V 250W.
Connected is a H-Bridge driving a 24V brushed motor with 13A current at full load (though starting current will be probably much higher).
Problem: The H-Bridge is ramping the motor up to speed by PWM (probably some khz, though I do not know yet). This is working fine with no load, with load two of the Mosfets (40V, 18A / 150A pulse) are burning through (=shortage) immediately. Interestingly these were two Mosfests not driven simultaniously (=of the two Mosfets switchend on to drive the motor, only one Mosfet did burn through).
Btw: the motor output of the bridge / mosfets are protected by a bidirectional TVS diode against inductive peaks from the motor. But there is no such protection (yet) at the supply input from the power supply.
The friend is abroad, thus I currently cannot go there and measure what is happening.
My guess is: the switch mode power supply does not like the PWM load and then outputs peaks of a too high voltage which is killing the Mosfets. However I never had experience with a pulsed load at a switch mode power supply and are seeking some advise if the above would be the most logical reason. Maybe somebody has some experience with these supplies.
Any other ideas?
[Ignore the H-bridge, this is proven to work fine and is well designed.]