In exemplary embodiments, methods, systems, and vehicles are provided for controlling operation of a vehicle in a fuel economy mode. In one embodiment, a vehicle is includes a battery, a generator, and a control system for controlling operation of the vehicle in a fuel economy mode, the control system including: (i) one or more current sensors configured to measure a battery current of the battery; and (ii) a processor coupled to the one or more current sensors and configured to at least facilitate controlling operation of the battery and the generator in the fuel economy mode utilizing a dynamic voltage threshold that is adjusted based on a comparison of the battery current with a baseload current threshold.

Methods and systems are provided for controlling an engine speed in a hybrid vehicle system during steady-state conditions and in response to transient acceleration and/or deceleration requests. In one example, an engine speed is controlled to an optimal engine speed for fuel economy during steady-state conditions, and in response to an acceleration or deceleration request, a target engine speed is obtained from a rate-limited optimal engine speed to vehicle speed ratio, and the engine is controlled to the target engine speed provided the target speed is below a threshold difference from optimal engine speed. In this way, the vehicle system may simulate a fixed ratio transmission during accelerations and decelerations, while maintaining optimal engine speed for fuel economy at steady state.

The state of charge of a traction battery of a hybrid vehicle power train is managed by, during a phase of running of the vehicle to a current destination, predicting a temperature that a battery will reach, after the power train is switched off, at a time of departure to a future destination; estimating, as a function of the battery temperature previously predicted, a minimum state of charge of the battery making it possible to provide, during a phase of running to the future destination, a predefined minimum power level; and maintaining the state of charge of the battery close to the minimum state of charge.

A control device for a hybrid vehicle is provided. When a first drive mode is selected as the drive mode of the hybrid vehicle, a control section shifts the drive mode to a second drive mode when a charge amount of a battery for an electric motor becomes smaller than or equal to a determination charge amount. The first drive mode operates the electric motor while an internal combustion engine is stopped. The second drive mode permits the operation of the internal combustion engine. The control section executes a shifting process when the upper limit system output is lower than or equal to a startup determination output even though the charge amount of the battery is greater than the determination charge amount. The shifting process shifts the drive mode to the second drive mode to start the internal combustion engine.

A hybrid vehicle includes: an engine; a catalyst; a motor generator; and a drive control unit. The catalyst is provided in an exhaust path of the engine. The motor generator is coupled to the engine and capable of regenerating electric power. The drive control unit is configured to increase torque output from the engine and cause the motor generator to regenerate the electric power by using the torque output from the engine in the case where the hybrid vehicle is in a deceleration state and a temperature of the catalyst is lower than a specified catalyst activation temperature.

A temperature control apparatus of a vehicle of the invention flows a cooling medium in an engine circulation circuit and a battery circulation circuit and an activation of an engine heat exchanging system so as not to perform an engine heat exchanging when an engine temperature is lower than an engine warming end temperature and a battery temperature is lower than a predetermined battery temperature lower than a battery warming end temperature, and flows the cooling medium in the engine circulation circuit and the battery circulation circuit and the activation of the engine heat exchanging system so as to perform the engine heat exchanging when the engine temperature is lower than the engine warming end temperature, and the battery temperature is equal to or higher than the predetermined battery temperature.

A controller for the hybrid vehicle compensates for a shortage of an engine output to a vehicle demand output by discharge electric power of a battery when the vehicle demand output is higher than an upper limit output of a target operating range, and charges the battery by an excess of the engine output to the vehicle demand output when the vehicle demand output is lower than a lower limit output of the target operating range. The target operating range is set to a low load side as a SOC of the battery is higher in a predetermined SOC range. Also, the controller controls an intake air temperature during stopping of the engine to a target intake air temperature when the hybrid vehicle is traveling with the engine stopped. The target intake air temperature is increased as the SOC is lower in the predetermined SOC range.

A method for controlling starting of a mild hybrid vehicle includes receiving a starting-request signal and in response, increasing a rotation speed of the engine by driving the MHSG by electricity supplied from a battery. Status data of the mild hybrid vehicle for controlling starting of the engine is monitored to obtain an engine rotation speed from the status data and determine an injection-starting rotation speed based on the status data. When the engine rotation speed is greater than the injection-starting rotation speed, fuel injection of the engine is started.

A hybrid electric vehicle (HEV) that includes one or more controller(s) configured to manage electric only and combustion engine drive modes, and at start-up, to generate a trip distance, and to detect an electric drive range, and battery, cabin, and powertrain thermal demands, among other conditions. The controller(s) engage a combustion engine drive mode if the distance exceeds the range, and the thermal demands exceed respective thresholds. The controller(s) also engage an electric drive mode if the range exceeds the distance, and the threshold exceed the thermal demands. Further variations include the controller(s) responsive to receiving a destination, and communicating the destination to a navigation system, and detecting if a charge event is likely to occur at the destination. In other arrangements, the controller(s) also adjust the trip distance upon detecting an historical probability of a charge event at the destination and whether the destination is a final destination.

A vehicle control apparatus includes a controller that selects an electric vehicle (EV) mode where an output clutch is disengaged and a wheel is driven by a motor, or a hybrid electric vehicle (HEV) mode where the output clutch is engaged and the wheel is driven by an engine and the motor. The controller engages the output clutch during the EV mode to adjust a gear ratio of a continuously variable transmission, and switches, in accordance with a battery state, an adjustment mode for the gear ratio, during the EV mode, between a first adjustment mode that allows the gear ratio to be adjusted in accordance with a vehicle speed, and a second adjustment mode that allows the gear ratio to be adjusted to and kept at a reference gear ratio smaller than a lowest speed gear ratio regardless of the vehicle speed.