CONTROL DEVICE AND CONTROL METHOD

摘要

In a conventional control device, there has been the problem of low induced voltage estimation accuracy due to a q-axis current flow at low rotational speed in magnet temperature estimation during three-phase short-circuit operation. The purpose of this invention is to more accurately estimate magnet flux or magnet temperature during three-phase short-circuit operation than the case using only d-axis current. A control device (1) is equipped with a phase short-circuit unit (50) for short-circuiting the three-phase terminals (51-1) to (51-3) of a permanent magnet synchronous machine (10) having a permanent magnet, and estimates the magnet state of the permanent magnet on the basis of the d-axis characteristics and q-axis characteristics during three-phase short-circuit operation in which the permanent magnet synchronous machine (10) is operated while the three-phase terminals (51-1 to 51-3) are short-circuited by the phase short-circuit unit (50).