| 摘要 |
PURPOSE:To effectively protect a heat damage by attaching a heat sensitive element to a base plate in which a semiconductor chip for forming a semiconductor module is mounted. CONSTITUTION:A semiconductor module 11 is used as a transistor inverter in a PWM controller of a synchronous motor. The synchronous motor M having a permanent magnet as a rotor, a PWM controlling circuit 21, a rotor position detector 22 such as a pulse encoder, etc., and a rectifier circuit 23 are provided. In this case, heat sensitive elements 14a, 14b are provided in the module 11, and the quantity of generated heat is detected in a real time. Thus, it can prevent a device from thermal damage due to an overload. |
