HYBRID CONSTRUCTION MACHINE

The hybrid constructions machine has an engine rotation speed sensor A to detect a rotation speed NE of an engine an engine state determination unit B to determine the state of output torque TE of the engine a load torque estimation unit C to calculate load torque TP of a hydraulic pump and an engine assistance limiting unit E to, when the rotation speed NE detected with the engine rotation speed sensor A is equal to or greater than a rotation speed N0, and the engine state determination unit B determines that the output torque TE of the engine has not become minimum torque Tmin, or the load torque TP calculated with the load torque estimation unit C is lower than torque T limit motive-power assistance with the motor generator to the engine