Abstract: A torque limit section that applies limit to a torque instruction value of an electric motor such that a switching elements temperature is restricted to no more than an element upper limiting temperature includes a torque restriction section that finds a torque restriction value for restricting the torque of the electric motor in accordance with the said switching elements temperature; a torque restriction mitigation section that finds a torque restriction mitigation value for mitigating the torque limit value in accordance with the integrated value of the deviation of the element upper limiting temperature and the switching elements temperature; a first subtractor that finds a torque restriction value by subtracting the torque restriction mitigation value from the torque limit value; and a second subtractor that finds a limited torque instruction value obtained by subtracting the torque limit value from the torque instruction value and outputs this to the gate generating section.

Abstract: A torque limit section that applies limit to a torque instruction value of an electric motor such that a switching elements temperature is restricted to no more than an element upper limiting temperature includes a torque restriction section that finds a torque restriction value for restricting the torque of the electric motor in accordance with the said switching elements temperature; a torque restriction mitigation section that finds a torque restriction mitigation value for mitigating the torque limit value in accordance with the integrated value of the deviation of the element upper limiting temperature and the switching elements temperature; a first subtractor that finds a torque restriction value by subtracting the torque restriction mitigation value from the torque limit value; and a second subtractor that finds a limited torque instruction value obtained by subtracting the torque limit value from the torque instruction value and outputs this to the gate generating section.

Abstract: A semiconductor device includes: a semiconductor element (106) having a surface on a positive electrode side and a surface on a negative electrode side; multiple conductors (13 to 15) bonded respectively to the surface on the positive electrode side and to the surface on the negative electrode side of the semiconductor element; a heat sink plate (11) disposed as intersecting a junction interface between the semiconductor element and each of the multiple conductors and configured to discharge heat of the semiconductor element; and an insulator (12) bonding the heat sink plate to the multiple conductors. The insulator includes a heat conductive insulator (16) disposed inside a portion facing all of the multiple conductors and a flexible insulator (17) disposed at a portion other than the heat conductive insulator.