Control system for hybrid construction machine
A control system for a hybrid construction machine includes: a turning motor provided in a turning circuit; a pressure detector for detecting a turning pressure of the turning motor; a variable displacement type of fluid pressure motor for regeneration which is rotated by means of pressurized fluid guided from the turning motor; a motor generator adapted to be rotated integrally with the fluid pressure motor; and a controller adapted to predict a turning regeneration flow from the turning motor on the basis of the turning pressure detected by pressure detector to control a tilt angle of the fluid pressure motor on the basis of the predicted turning regeneration flow.
1. A control system for a hybrid construction machine, comprising:
a turning motor provided in a turning circuit;
a pressure detector for detecting a turning pressure of the turning motor;
a variable displacement type of fluid pressure motor for regeneration, the fluid pressure motor being rotated by means of pressurized fluid guided from the turning motor;
a motor generator adapted to be rotated integrally with the fluid pressure motor;
a controller adapted to read out, from a table that stores a plurality of reference pressures, and a plurality of reference turning regeneration flows each of which corresponds to a respective one of the plurality of reference pressures, one of the plurality of reference turning generation flows that corresponds to the turning pressure detected by the pressure detector to predict a turning regeneration flow from the turning motor, and control a tilt angle of the fluid pressure motor on the basis of the predicted turning regeneration flow.
2. The control system for a hybrid construction machine according to claim 1 , further comprising:
an on-off valve provided on the downstream side of the pressure detector in a passage by which the turning circuit is connected to the fluid pressure motor;
wherein the controller opens the on-off valve to guide a turning regeneration flow to the fluid pressure motor in a case where the turning pressure detected by the pressure detector reaches a threshold value set up in advance.
3. The control system for a hybrid construction machine according to claim 1 , further comprising:
a boom cylinder,
wherein the controller controls the tilt angle of the fluid pressure motor on the basis of a total flow of a regeneration flow of the boom cylinder and the predicted turning regeneration flow.
4. A method for a control system for a hybrid construction machine, the control system including a turning motor provided in a turning circuit, a pressure detector for detecting a turning pressure of the turning motor, a variable displacement type of fluid pressure motor for regeneration rotated by means of pressurized fluid guided from the turning motor, and a motor generator adapted to be rotated integrally with the fluid pressure motor, the method comprising:
detecting a turning pressure of the turning motor by the pressure detector;
predicting a turning regeneration flow from the turning motor on the basis of the turning pressure detected by the pressure detector; and
performing an open-loop control for controlling a tilt angle of the fluid pressure motor on the basis of the predicted turning regeneration flow.
5. A control system for a hybrid construction machine, comprising:
a turning motor provided in a turning circuit;
a pressure detector for detecting a turning pressure of the turning motor;
a variable displacement type of fluid pressure motor for regeneration, the fluid pressure motor being rotated by means of pressurized fluid guided from the turning motor;
a motor generator adapted to be rotated integrally with the fluid pressure motor; and
a non-feedback controller adapted to predict a turning regeneration flow from the turning motor on the basis of the turning pressure detected by the pressure detector and perform an open-loop control for controlling a tilt angle of the fluid pressure motor on the basis of the predicted turning regeneration flow without using feedback control.
6. The control system for a hybrid construction machine according to claim 5 , further comprising:
an on-off valve provided on the downstream side of the pressure detector in a passage by which the turning circuit is connected to the fluid pressure motor;
wherein the non-feedback controller opens the on-off valve to guide a turning regeneration flow to the fluid pressure motor in a case where the turning pressure detected by the pressure detector reaches a threshold value set up in advance.
7. The control system for a hybrid construction machine according to claim 5 , further comprising:
a boom cylinder,
wherein the non-feedback controller controls the tilt angle of the fluid pressure motor on the basis of a total flow of a regeneration flow of the boom cylinder and the predicted turning regeneration flow.