Methods and systems are provided for enabling vehicle speed control without overfilling a system battery. In one example, braking energy is applied (or recuperated) by applying a negative torque from BISG until a system battery has been sufficiently charged. Thereafter, the electrical power generated by the BISG is used to operate an electric boost assist motor, and the energy is recuperated in the form of stored compressed air.

A control system for a hybrid vehicle configured to reduce electricity consumption by a motor in a condition where a maximum output torque of an engine is restricted. A controller is configured to: calculate a current maximum torque of the engine when increasing a speed of the engine to achieve an acceleration demand; determine whether the current maximum torque of the engine is less than an inertia torque required to increase the speed of the engine; and adjust the reaction torque of the first motor to a value less than a predetermined value, if the current maximum torque of the engine is less than the inertia torque required to increase the speed of the engine.

An exhaust brake torque system for a vehicle including an engine includes a controller configured to determine a current exhaust brake torque and a maximum exhaust brake torque. A display is configured to display at least one of the current exhaust brake torque, the maximum exhaust brake torque and a percentage corresponding to the current exhaust brake torque divided by the maximum exhaust brake torque. An engine speed sensor determines an engine speed of an engine. A pressure sensor is configured to sense turbine inlet pressure. The controller is configured to calculate the current exhaust brake torque and the maximum exhaust brake torque in response to the engine speed and the turbine inlet pressure.

An exhaust brake torque system for a vehicle including an engine includes a controller configured to determine a current exhaust brake torque and a maximum exhaust brake torque. A display is configured to display at least one of the current exhaust brake torque, the maximum exhaust brake torque and a percentage corresponding to the current exhaust brake torque divided by the maximum exhaust brake torque. An engine speed sensor determines an engine speed of an engine. A pressure sensor is configured to sense turbine inlet pressure. The controller is configured to calculate the current exhaust brake torque and the maximum exhaust brake torque in response to the engine speed and the turbine inlet pressure.

When a noise generation duration time predicted by a prediction unit is equal to or less than a predetermined time and it is predicted that generation of noise can be further curbed in comparison with a case in which the noise generation duration time in which noise is generated is relatively short and the noise generation duration time is greater than the predetermined time, an engine operating point control unit controls an engine and a differential unit such that an engine operating point reaches an engine operating point in an optimal fuel-efficiency operating line and thus it is possible to curb generation of noise and to curb a decrease in fuel efficiency.

An engine system may include an engine including a plurality of intake lines through which outside air supplied to combustion chamber flows, a first electric supercharger and a second electric supercharger disposed respectively in the plurality of intake lines, a first exhaust gas recirculation (EGR) device including a first EGR line branched from an exhaust manifold and joining an intake manifold and a first EGR valve disposed in the first EGR line, and a controller determining an engine target torque according to a driving condition of the engine, setting an engine torque within an operation region of the first EGR device when the engine target torque is in a torque dead band between the operation region of the first EGR device and a non-operation region thereof, and compensating a difference value between the engine target torque and the engine torque by a hybrid electric vehicle (HEV) motor.

A variable speed hybrid electric supercharger assembly is controlled to regulate an adaptive state of charge of an energy storage device and/or to boost an engine based on a performance mode selected by a driver. In one example, a reference state of charge is determined based upon driving characteristics of a vehicle and compared to an actual state of charge of the energy storage device. If the difference indicates a deficit, an operation mode is selected to regenerate the energy storage device. In another example, a planetary gearing arrangement between an engine and an electric motor is configured to increase or decrease power transferred to the supercharger by the engine based upon the performance mode selected by the driver.

There are provided a controller and a control method for a hybrid vehicle including an engine with a supercharger serving as a drive power source for travel, a rotary machine serving as a drive power source for travel, and a power storage device configured to transmit and receive electric power to and from the rotary machine. The controller determines whether an operation of the supercharger is limited, compensates for a torque shortage of the engine due to limitation of the operation of the supercharger by a torque of the rotary machine when it is determined that the operation of the supercharger is limited, and curbs a decrease in an amount of electric power stored in the power storage device more when it is determined that the operation of the supercharger is limited than when it is determined that the operation of the supercharger is not limited.

A control device for a hybrid vehicle includes: a drive control unit that calculates required drive power which is required for a hybrid vehicle based on an accelerator opening when an accelerator return operation is performed, calculates a target engine output which changes slowly with respect to a required engine output for realizing the required drive power through slow change processing, and controls an engine, a first rotary machine, and a second rotary machine such that an engine output reaches the target engine output; and a smoothing rate setting unit that changes a smoothing rate which is used for the slow change processing based on a supercharging pressure and sets the smoothing rate to a smaller value when the supercharging pressure is high than when the supercharging pressure is low.

When it is determined that there is a likelihood of occurrence of an abnormality in a supercharger, a maximum engine rotation speed and a maximum MG2 rotation speed are changed to a low rotation speed side and operating points of an engine and a rotary machine are controlled such that an engine rotation speed and an MG2 rotation speed are respectively within ranges which do not exceed the changed maximum rotation speeds. Accordingly, even when the supercharger does not operate normally and an abnormal increase in a supercharging pressure occurs, it is possible to curb a high-rotation state of the engine rotation speed and the MG2 rotation speed. As a result, even when an abnormal increase in the supercharging pressure occurs, it is possible to curb a decrease in durability of components.