| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a controller for a motor driving system capable of suppressing the generation of a crack in solder without damaging the driving capacity of a motor. <P>SOLUTION: A PCU 10 includes a converter 12 and an inverter 14, and is configured so that a DC voltage output by a DC power supply B can be converted into the driving voltage of an AC motor MG. The PCU 10 contains switching elements Q1, Q2 and Q11 to Q16 fixed on a substrate by solder. The controller 50 controls the switching operations of the switching elements so that the AC motor MG outputs a torque according to a torque command value. The controller 50 computes a cumulative frequency by accumulating a frequency with the quantity of a temperature rise from an initial temperature as a reference value regarding the temperatures of the switching elements detected by a temperature sensor 30. The controller 50 limits the output torque of the AC motor MG when the computed cumulative frequency exceeds a predetermined allowable value in response to the stress strength of solder. <P>COPYRIGHT: (C)2011,JPO&INPIT |
