| 摘要 |
PROBLEM TO BE SOLVED: To solve the problem in which calculation of the voltage generated by current is not accurate because a change by current is large in q-axis inductance.SOLUTION: A temperature estimating device of a synchronous motor comprises: a voltage command generation unit which controls d-phase current by increasing or decreasing d-phase voltage and q-phase voltage by a command; a voltage acquiring unit which acquires d-phase voltage and q-phase voltage when the d-phase current is changed; a rotational speed detecting unit which detects a rotational speed of the synchronous motor; a current detecting unit which detects d-phase current and q-phase current; a winding temperature acquiring unit; a winding resistance converting unit which calculates winding resistance from a winding temperature; an inductance calculating unit which calculates d-axis inductance on the basis of a changed portion of the d-phase current, a changed portion of the q-phase voltage, and the rotational speed; a counter-electromotive voltage constant calculating unit which calculates a counter-electromotive voltage constant from the q-phase voltage, post-change d-phase current, the rotational speed, the q-phase current, and the winding resistance; and a magnet temperature estimating unit which estimates a magnet temperature on the basis of the counter-electromotive voltage constant.SELECTED DRAWING: Figure 1 |
