An anomaly detector of a permanent magnet synchronous electric motor (1, 2), comprising: a plurality of permanent magnet synchronous electric motors (1, 2); a current command value calculator configured to calculate current command values relative to the plurality of the permanent magnet synchronous electric motors: and q-axis voltage command value calculators (18, 28) configured to calculate each of q-axis voltage command values relative to the plurality of the permanent magnet synchronous electric motors (1, 2) based on the current command values each calculated by the current command value calculator; characterized by a magnet temperature anomaly determiner configured to determine whether or not an anomaly of a magnet temperature is caused to at least any one of the permanent magnet synchronous electric motors (1, 2), and configured to use a difference between: a q-axis voltage command value (Vqr*) which is calculated by one of the q-axis voltage command value calculators (18, 28) and is relative to one permanent magnet synchronous electric motor (1, 2) of the plurality of the permanent magnet synchronous electric motors (1, 2), and a q-axis voltage command value (Vql*) which is calculated by another of the q-axis voltage command value calculators (28, 18) and is relative to another permanent magnet synchronous electric motor (2, 1) of the plurality of the permanent magnet synchronous electric motors (1, 2). a plurality of permanent magnet synchronous electric motors (1, 2); a current command value calculator configured to calculate current command values relative to the plurality of the permanent magnet synchronous electric motors: and q-axis voltage command value calculators (18, 28) configured to calculate each of q-axis voltage command values relative to the plurality of the permanent magnet synchronous electric motors (1, 2) based on the current command values each calculated by the current command value calculator; characterized by a magnet temperature anomaly determiner configured to determine whether or not an anomaly of a magnet temperature is caused to at least any one of the permanent magnet synchronous electric motors (1, 2), and configured to use a difference between: a q-axis voltage command value (Vqr*) which is calculated by one of the q-axis voltage command value calculators (18, 28) and is relative to one permanent magnet synchronous electric motor (1, 2) of the plurality of the permanent magnet synchronous electric motors (1, 2), and a q-axis voltage command value (Vql*) which is calculated by another of the q-axis voltage command value calculators (28, 18) and is relative to another permanent magnet synchronous electric motor (2, 1) of the plurality of the permanent magnet synchronous electric motors (1, 2). a q-axis voltage command value (Vqr*) which is calculated by one of the q-axis voltage command value calculators (18, 28) and is relative to one permanent magnet synchronous electric motor (1, 2) of the plurality of the permanent magnet synchronous electric motors (1, 2), and a q-axis voltage command value (Vql*) which is calculated by another of the q-axis voltage command value calculators (28, 18) and is relative to another permanent magnet synchronous electric motor (2, 1) of the plurality of the permanent magnet synchronous electric motors (1, 2).