Methods and systems are provided for enabling turbocharger shaft speed control without overfilling a system battery. In one example, shaft speed is reduced by applying a negative torque from an electric boost assist motor until a system battery has been sufficiently charged. Thereafter, electrical power from shaft braking is recuperated by commanding a positive torque onto a driveline of the vehicle via a BISG.

A control apparatus for a rotating electric machine is provided. The rotating electric machine includes a moving portion that applies torque to a drive shaft of an internal combustion engine. The control apparatus acquires a rotational frequency signal that is a signal that changes depending on a rotational frequency of the moving portion per unit time. The control apparatus calculates a damping torque that is applied from the moving portion to the drive shaft to suppress vibration during operation of the internal combustion engine. The control apparatus calculates the damping torque based on the rotational frequency signal acquired by the signal acquiring unit in response to the rotating electric machine performing cranking of the internal combustion engine.

A method for ascertaining an accuracy of a torque transmitted by a belt-driven starter generator of an internal combustion engine to the internal combustion engine, the method being similar to a learning operation or a calibration of the actual torque of the starter generator with respect to a setpoint torque, includes: in an idling instance of the internal combustion engine, controlling the belt-driven starter generator to transmit a specified test torque to the internal combustion engine and decreasing the torque of the internal combustion engine by the specified test torque; determining and evaluating a speed variable, which is a function of a speed of the internal combustion engine; and deducing the torque accuracy from the evaluated speed variable.

An electric starter system is usable with an engine and a power inverter module (PIM), e.g., of a powertrain. The starter system includes a polyphase/AC brushless starter motor connected to the PIM via an AC voltage bus and selectively connected to the engine during a requested engine start event. A sensor on the DC voltage bus outputs a signal indicative of a voltage level of the DC voltage bus. The controller executes a method using voltage stabilization logic having a proportional-integral (PI) torque control loop. Logic execution in response to the requested engine starting event causes the controller to control the starter motor, when the bus voltage exceeds a calibrated minimum voltage, using a starting torque determined via the control loop. The commanded starting torque limits inrush current to the starter motor such that the DC voltage bus remains above the minimum voltage.

When an engine is stopped, a rotational position at a time when a crankshaft starts rotating in a reverse direction is predicted based on a rotational position detected by a crank angle sensor. A target rotational position is set within a range of the crankshaft rotational position between a time when the exhaust valve of one of four cylinders in the expansion stroke when the crankshaft starts rotating in the reverse direction is opened and a time when the expansion stroke of the cylinder ends. When the predicted rotational position is behind the target rotational position, a torque applying device applies a positive rotational torque to the crankshaft. At the time when the exhaust valve of the cylinder in the expansion stroke when the crankshaft starts rotating in the reverse direction is opened, application of the positive rotational torque from the torque applying device to the crankshaft is stopped.

System comprising an internal combustion engine including a crankshaft, a crankshaft sprocket coupled to the crankshaft, an electric motor in mechanical communication with the crankshaft sprocket, a bidirectional engine position sensor coupled to the crankshaft sprocket, a controller in electrical communication with the bidirectional engine position sensor and a non-transitory memory having instructions that, in response to execution by a processor, cause the processor to determine a position of an engine component upon shutdown of the engine, store the position of the engine component at shutdown in the non-transitory memory, and control the electric motor at restart in response to the position of the engine component at shutdown are disclosed. Methods are also disclosed.

A method for guaranteeing starting performance of an engine for maintaining driving performance is provided. The method includes executing a quasi-failure mode in which the engine is changed to a driving state when an engine cranking apparatus state is maintained equal to or less than a threshold for a predetermined period of time. As a result, the engine is driven in the quasi-failure mode while the hybrid vehicle is driven in the EV mode to prevent the vehicle system from being aggravated and fundamentally preventing the degradation in the stability of the vehicle causing driver discomfort.

A controller is configured to respond to an engine start command, operate the engine to produce excess torque beyond a demand torque, and in response to engine speed achieving a threshold, operate the starter-generator to load the engine to consume the excess torque and drive the engine speed toward an electric machine speed, and engage a clutch to couple the engine and an electric machine.

A control apparatus for a rotating electric machine is provided. The rotating electric machine includes a moving portion that applies torque to a drive shaft of an internal combustion engine. The control apparatus acquires a rotational frequency signal that is a signal that changes depending on a rotational frequency of the moving portion per unit time. The control apparatus calculates a damping torque that is applied from the moving portion to the drive shaft to suppress vibration during operation of the internal combustion engine. The control apparatus calculates the damping torque based on the rotational frequency signal acquired by the signal acquiring unit in response to the rotating electric machine performing cranking of the internal combustion engine.

A vehicle includes a rotary electric machine, an internal combustion engine, a temperature sensor, and a limiter. The rotary electric machine generates power to move the vehicle. The internal combustion engine is started by the rotary electric machine to generate power to move the vehicle. The temperature sensor detects temperature of the rotary electric machine or of a drive circuit for the rotary electric machine. The limiter restricts the power generated by the rotary electric machine if the temperature is higher than a first threshold temperature. The start prohibitor prohibits the rotary electric machine from starting the internal combustion engine if the temperature is higher than a second threshold temperature which is higher than the first threshold temperature.