| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide hybrid construction machinery capable of enhancing working efficiency by achieving continuous running. <P>SOLUTION: In a shovel, a controller 30 performs control for decreasing an upper limit value of an electric current supplied to an AC motor such as an electric motor for slewing, when the temperature of cooling water for cooling an inverter reaches an output suppression temperature or above. Thus, a rise in the temperature of the inverter is suppressed. Since the output suppression temperature is lower than an operation stop temperature as a temperature which makes the inverter start the operation of a mechanism stopping the supply of the electric current to the AC motor, the controller performs the control for making the inverter decrease the upper limit value of the electric current supplied to the AC motor, before the AC motor is stopped. This prevents the AC motor from being stopped due to an abnormality in the temperature, and achieves the continuous running of the shovel. <P>COPYRIGHT: (C)2011,JPO&INPIT |
