When an external stator field opposes the magnet’s field (e.g., during a short-circuit fault or at high load with advanced current angle), the operating point moves down the curve. If it crosses below the knee at the operating temperature, the magnet loses flux permanently.
In Ansys Maxwell, demagnetization analysis is essential for evaluating the risk of permanent magnets losing their strength due to high temperatures, short circuits, or heavy loading. Irreversible demagnetization occurs when the operating point of a magnet falls below the "knee point" of its Demagnetization Analysis Procedure ansys maxwell demagnetization