A stop/start hybrid vehicle includes an engine configured for stopping and restarting during travel, a multiple-ratio transmission, a brake pedal, and an electronic parking brake. The transmission can be shifted into reverse gear either when the brake pedal is applied or unapplied. At least one controller is programmed to control the vehicle under these scenarios. If the engine is off and the brake pedal is applied when the transmission is shifted into reverse, the controller restarts the engine. If the engine is off and the brake pedal is unapplied when the transmission is shifted into reverse, the controller inhibits the engine from restarting until the brake pedal is applied. The controller can also be programmed to apply the electronic parking brake while the brake pedal remains unapplied after a predetermined time from the transmission being shifted into the reverse gear.

A power system for a locomotive. The power system includes an alternator, a first inverter system, a traction motor, a second inverter system and an auxiliary power unit. The first inverter system is coupled to the alternator and receives high voltage power from the alternator. The traction motor is coupled to the first inverter system receives high voltage power from the first inverter system. The second inverter system is also coupled to the alternator. The second inverter system steps down the high voltage power from the alternator. The auxiliary power unit is coupled to the second inverter system and receives the stepped down voltage power from the second inverter system.

The purpose of the present invention is to swiftly start up an engine in a range in which electrical equipment having electric power supplied thereto by a battery is not reset, even in cases when the battery is insufficiently charged and the battery is deteriorated. An engine start-up device according to the present invention starts up an engine by transmitting, to the engine, the rotary force of a direct-current motor driven by a battery. The engine start-up device is provided with: a battery-voltage acquisition unit for acquiring the battery voltage of the battery; a target-current-value calculation unit which calculates, on the basis of the battery voltage acquired by the battery-voltage acquisition unit, a target current value for a motor current to be supplied from the battery to the direct-current motor; and a motor-current control unit for controlling a switching element which is connected to the direct-current motor, and through which the motor current flows, such that the motor-current value of the motor current approaches the target current value.

Disclosed is a method for assistance in starting a heat engine of a motor vehicle including an auxiliary network supplied by a low-voltage auxiliary battery and by a voltage-controlled DC current source. This method is launched in the first place when the electronic control system of the vehicle is woken up as a result of a specific action performed by a user, which may be followed by an action of starting the heat engine. This method also consists in controlling the current source so as to cause it to operate at its maximum power during a time interval adapted to reach a maximum positive polarization of the auxiliary battery, and then, at the end of this time interval, in the absence of an effective starting command, controlling the current source so as to cancel the current flowing in the auxiliary battery.

The electrical supply system according to the invention is of the type comprising, on the one hand, an electrical power network having a first voltage electrically connecting first items of equipment comprising an electrical motor/generator, an inverter/rectifier and a first electrical energy store, and, on the other hand, an electrical service network having a second voltage that is less than the first voltage electrically connecting second items of equipment comprising a second electrical energy store, an electronic control unit controlling the energy transfers between the power network and the service network by means of at least one reversible DC/DC converter. The electronic unit comprises a first electronic module supplied by the power network exchanging information with the first items of equipment, and a second electronic module supplied by the service network exchanging information with the second items of equipment and electrically insulated from the first module.

A system and method for controlling engine starting in a hybrid vehicle having an engine, a first electric machine selectively coupled to the engine by a first clutch, a second electric machine coupled to the engine, a step-ratio transmission selectively coupled to the electric machine by a second clutch include starting the engine using either the first electric machine or the second electric machine based on engine stop position. The first electric machine may be a low voltage starter motor or integrated starter-generator. The system and method may use the first electric machine when the engine stop position is within a specified range of positions relative to a piston top dead center position associated with higher cranking torques.

A hybrid vehicle includes: an engine; a motor; a drive system battery connected to a drive system power line; an auxiliary system battery connected to an auxiliary system power line; a bidirectional power converter configured to step down power on the drive system power line to supply the stepped-down power to the auxiliary system power line, and configured to boost power on the auxiliary system power line to supply the boosted power to the drive system power line; and a control device. The control device is configured to, upon a cold start in which the engine is started, control the engine, the motor, and the bidirectional power converter to cause the motor to crank the engine while causing the bidirectional power converter to boost the power on the auxiliary system power line to supply the boosted power to the drive system power line.

A method for operating a vehicle that includes a DC/DC converter is described. In one example, the method includes adjusting an output voltage of the DC/DC converter after the DC/DC converter is used to crank an engine. The output voltage of the DC/DC converter may be adjusted responsive to a state of charge of an ultra-capacitor.

A power supply and an automotive topology that includes the power supply, the power supply having an integrated module, which includes in a common, shared module housing, a start-stop DC/DC converter, a DC/AC converter, and an auxiliary DC/DC converter, which bypasses stop/start during non-stop/start operation. A DC input port connected to the start-stop DC/DC converter, DC/AC converter, and the auxiliary DC/DC converter. A DC output port connected to the start-stop DC/DC converter to supply DC to critical loads of a motor vehicle, even during vehicle OFF mode. An AC output port connected to the DC/AC converter to supply AC to an external component.

An energy storage system (ESS) for a vehicle propulsion system includes a first battery electrically coupled to a first voltage bus, a second battery electrically coupled to a second voltage bus, and a bidirectional DC/DC power converter electrically coupled to the voltage buses. A starter for cranking an engine is electrically coupled to the first voltage bus. A controller executes computer code stored in memory. The computer code is configured to operate the converter in a boost mode to transfer power from the second voltage bus to the first voltage bus, in response to the controller determining that: a power capability of the first battery is below a power demand on the first voltage bus; a state of charge of the first battery is below a state of charge threshold; or a temperature of the first battery is below a temperature threshold.