SUPERCHARGING SYSTEM, CONTROL DEVICE FOR SUPERCHARGING SYSTEM, AND METHOD FOR OPERATING SUPERCHARGING SYSTEM

摘要

A supercharging system is provided with a first supercharger that comprises a first compressor, a second supercharger that comprises a second compressor, and a control device for controlling the first and the second superchargers. The first or the second supercharger comprises an electric motor that drives the compressor. The first or the second supercharger comprises a turbine that is rotationally driven by exhaust gas from an engine and a nozzle vane that adjusts the area of a flow path for exhaust gas toward the turbine. The control device comprises: an electric motor control unit that sets the upper limit value of an output command value for the electric motor to a low value or switches the electric motor to regenerative operation when the charge amount of a battery is less than a first threshold value; and a vane control unit that controls the opening degree of the nozzle vane so as to decrease the area of the flow path together with control of the electric motor by the electric motor control unit when the charge amount of the battery is less than the first threshold value.