HYBRID CONSTRUCTION MACHINE

摘要

The hybrid constructions machine has an engine rotation speed sensor 11A to detect a rotation speed NE of an engine 11, an engine state determination unit 20B to determine the state of output torque TE of the engine 11, a load torque estimation unit 20C to calculate load torque TP of a hydraulic pump 13, and an engine assistance limiting unit 20E to, when the rotation speed NE detected with the engine rotation speed sensor 11A is equal to or greater than a rotation speed N0, and the engine state determination unit 20B determines that the output torque TE of the engine 11 has not become minimum torque Tmin, or the load torque TP calculated with the load torque estimation unit 20C is lower than torque T1, limit motive-power assistance with the motor generator 12 to the engine 11.

主权项

1. A hybrid construction machine comprising:
an engine; a hydraulic pump driven with the engine; a hydraulic working unit driven with pressure oil discharged from the hydraulic pump; a motor generator that transmits torque to the engine, and performs motive-power assistance to the engine and power generation; a power storage device that supplies/receives electric power to/from the motor generator; an engine rotation speed detection unit that detects a rotation speed of the engine; an engine state determination unit that determines a state of output torque of the engine; a load torque detection unit that detects load torque of the hydraulic pump; and an engine assistance limiting unit that, when the rotation speed of the engine detected with the engine rotation speed detection unit is equal to or greater than a predetermined rotation speed, and the engine state determination unit determines that the output torque of the engine has not become predetermined minimum torque, or the load torque of the hydraulic pump detected with the load torque detection unit is lower than predetermined torque, limits the motive-power assistance with the motor generator to the engine.