An engine system is provided, which includes a supercharger driven by a crankshaft of an engine, an electromagnetic clutch disconnectably connecting the crankshaft to the supercharger, and a controller configured to output a control signal to the electromagnetic clutch. The controller includes a processor configured to execute an uphill-angle detecting module to detect an uphill angle during traveling of a vehicle, an uphill determining module to determine whether the detected uphill angle is above a given first uphill angle, and a boost controlling module to, when the detected uphill angle is above the first uphill angle, control the electromagnetic clutch to connect the crankshaft to the supercharger even when a target torque of the engine is within a not-boosting range.

An engine system is provided, which includes a supercharger driven by a crankshaft of an engine, an electromagnetic clutch disconnectably connecting the crankshaft to the supercharger, and a controller configured to output a control signal to the electromagnetic clutch. The controller includes a processor configured to execute an uphill-angle detecting module to detect an uphill angle during traveling of a vehicle, an uphill determining module to determine whether the detected uphill angle is above a given first uphill angle, and a boost controlling module to, when the detected uphill angle is above the first uphill angle, control the electromagnetic clutch to connect the crankshaft to the supercharger even when a target torque of the engine is within a not-boosting range.

An engine system provided to a vehicle having an accelerator pedal is provided. When an engine operation range is determined to shift to a first range (where an electromagnetic clutch is disengaged) from a second range (where the clutch is engaged) after an opening of the accelerator pedal increases at a rate below a given reference rate, the clutch is switched from ON to OFF after a given basic stand-by period passes from the shift. When the engine operation range is determined to shift from the second range to the first range after the accelerator pedal opening increases at the given reference rate or above, the clutch is switched from ON to OFF after a given acceleration stand-by period (longer than the basic stand-by period by a given added period) passes from the shift.

An example engine system is disclosed. The engine system may control a turbocharger of an internal combustion engine, and more particularly control a boost pressure provided by a turbocharger to an internal combustion engine. An example method for controlling a boost pressure provided by a turbocharger may include receiving a boost pressure demand and identifying a compressor speed demand to achieve the received boost pressure demand. The method may also include converting the compressor speed demand into a kinetic energy demand of the turbocharger rotating components and controlling the kinetic energy of the turbocharger rotating components to meet the kinetic energy demand by controlling power supplied by the turbine and the electric motor assist.

An example engine system is disclosed. The engine system may control a turbocharger of an internal combustion engine, and more particularly control a boost pressure provided by a turbocharger to an internal combustion engine. An example method for controlling a boost pressure provided by a turbocharger may include receiving a boost pressure demand and identifying a compressor speed demand to achieve the received boost pressure demand. The method may also include converting the compressor speed demand into a kinetic energy demand of the turbocharger rotating components and controlling the kinetic energy of the turbocharger rotating components to meet the kinetic energy demand by controlling power supplied by the turbine and the electric motor assist.

A method and a turbine-compressor assembly of a system having an engine includes an upstream valve coupled with a compressor and a turbine-compressor device, a downstream valve coupled with a turbine and the device, and a controller to control the upstream, downstream, and a control valve. The controller selectively operates the device in a plurality of operating modes. In a turbine mode of operation, the upstream valve directs inlet air to the compressor, the turbine receives engine exhaust, the downstream valve directs first turbine exhaust from the turbine to the device, and the control valve directs second turbine exhaust from the device to an outlet. In a compressor mode of operation, the control valve directs the inlet air to the device, the upstream valve directs first compressed air from the device to the compressor, and the downstream valve directs the first turbine exhaust from the turbine to the outlet.

A method and a turbine-compressor assembly of a system having an engine includes an upstream valve coupled with a compressor and a turbine-compressor device, a downstream valve coupled with a turbine and the device, and a controller to control the upstream, downstream, and a control valve. The controller selectively operates the device in a plurality of operating modes. In a turbine mode of operation, the upstream valve directs inlet air to the compressor, the turbine receives engine exhaust, the downstream valve directs first turbine exhaust from the turbine to the device, and the control valve directs second turbine exhaust from the device to an outlet. In a compressor mode of operation, the control valve directs the inlet air to the device, the upstream valve directs first compressed air from the device to the compressor, and the downstream valve directs the first turbine exhaust from the turbine to the outlet.

A rotation adjusting device is controlled such that an engine speed rising rate at the time of acceleration request is made smaller when a turbocharging pressure is lower than the turbocharging pressure is higher. Therefore, an engine speed can be increased at such a low speed that a rising delay in the turbocharging pressure hardly occurs, in a low turbocharging pressure region. Further, when the rotation adjusting device is controlled such that the engine speed rising rate at the time of the acceleration request is set to a value corresponding to the turbocharging pressure, an MG2 torque is controlled to compensate for an insufficient drive torque of an actual engine torque for a request engine torque. Therefore, even when the engine torque is increased slowly by increasing the engine speed at a slow speed, the insufficient drive torque is compensated for by the MG2 torque.

Systems and methods are described for operating a turbocharger. A current exhaust manifold pressure is determined based on an engine operating condition. A current operating condition of the turbocharger is determined. A surge correction factor is determined based on the current operating condition of the turbocharger. The current exhaust manifold pressure is adjusted based on the surge correction factor.

Systems and methods are described for operating a turbocharger. A current exhaust manifold pressure is determined based on an engine operating condition. A current operating condition of the turbocharger is determined. A surge correction factor is determined based on the current operating condition of the turbocharger. The current exhaust manifold pressure is adjusted based on the surge correction factor.