In this thesis we describe the concept of protection circuit, that safely isolates inverter from the machine.
The purpose was simulation of such circuit, design of a prototype and test measurements.
The idea is to safely disconnect all motor phases from inverter, and also make a three phase short circuit to
stop the machine rotation. We confirm this with simulations in LTspice, where we also test the limits of the
concept. After designing the prototype we confirm the importance of the delay between the moment of breaking the
phase connection and performing short circuit, on the over-voltage generated by breaking current connection.
In the end we confirm the operation of the circuit with measurement results and suggest possible corrections and
improvements of the concept or prototype.
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