| Abstract |
A bridge converter is as reliable as his protection. Conventional methods of protection reach their limit by increasing frequency. This paper presents a practical solution for a "dynamic" protection circuit. It is an application on a threephase inverter with powermosfets (BUZ80A Siemens) for the PWM-drive of a 1kW induction motor. Our philosophy consists in watching the actual situation of the switch (on, off, short-circuited) and to use this information to control the conduction of the other mosfets. The presented principles are of course also applicable for inverters with bipolar transistors whatever the switched power. |
