Abstract: A method is disclosed for estimating engine power output for an engine in a hybrid electric vehicle powertrain that includes an electric motor and an electric generator. Selected powertrain variables, including electric motor torque and electric generator torque, are used in determining desired vehicle traction wheel torque and an estimated engine power. A calibrated delay in calculating estimated engine power following a time sampling of the values for motor torque and generator torque avoid inertial effects.

Abstract: A parallel hybrid electric vehicle powertrain and control method wherein an internal combustion engine and an electric motor system define a split power operating mode, a generator drive mode and a parallel power mode. Provision is made, when the motor is inoperable, for preventing discharge of a battery in the electric motor system when the battery state-of-charge is low and for delivering power from the battery when the battery state-of-charge is greater than a predetermined value.

Abstract: A vehicle and method for controlling an engine in a vehicle are provided. A temperature of a lubricating fluid in the engine is determined, as are first and second engine speed limits. Operation of the engine at the first engine speed limit is limited to a predetermined time period when the lubricating fluid temperature is between first and second predetermined temperatures. The engine speed is at least temporarily limited to the second engine speed limit after the engine has been operated at the first engine speed limit for the predetermined time period and the lubricating fluid temperature is between the first and second predetermined temperatures.

Abstract: A method for estimating traction wheel torque in a hybrid electric vehicle powertrain that does not require a torque sensor. The method relies upon variables including speed, torque, moments of inertia and angular acceleration of powertrain components. Separate strategy routines are used for a parallel operating mode and for a non-parallel operating mode.

Abstract: An energy producing and storage system for a vehicle includes a compressed gas storage tank having a generally cylindrical outer wall and a generally cylindrical battery having a partially triangular section defined in part by a concave surface extending along and nested with at least a portion of the cylindrical outer wall of the gas storage tank. The energy producing and storage system also includes a fuel cell disposed in a concavity formed in the vehicle body, thereby further minimizing the passenger and/or trunk space required to accommodate the system.

Abstract: A method and system for controllably transferring energy from a high voltage bus to a low voltage bus in a hybrid electric vehicle. A vehicle system controller controls a DC/DC converter coupled between the high voltage bus and the low voltage bus to control the transfer of energy therebetween.

Abstract: A method for controlling engine idle in a vehicle having a motor connected to the engine through a power transfer unit is provide. Upon receiving a neutral command, the engine torque is commanded to approximately zero. The motor torque is adjusted to maintain an approximately constant engine speed as the engine torque is reduced. The torque from the engine transferred to the vehicle wheels is at or near zero. When the torque at the vehicle wheels is non-zero, a second motor is used to cancel the torque output from the engine so the torque at vehicle wheels is zero. When the engine torque has reached approximately zero, or when a predetermined amount of time has past, both motors are shutdown, and all of the remaining engine torque is transferred to the first motor through the power transfer unit.

Abstract: A method and system of engine state determination includes a plurality of requestors each of which compares vehicle or environmental conditions to a requirement and outputs a request state variable. The requestors are grouped according to function or component and the request state variables are combined and simplified at the output of each group. A state machine receives the final combined and simplified request state, and evaluates it according to the active or inactive status of the requests. The state machine carries out the proper state transition and outputs the desired engine state to engine control algorithms that start or stop the engine as necessary.

Abstract: A controller and a control method for modifying battery discharge and charge power limits in a vehicle powertrain that includes an electric battery as a power source. The modification compensates for inaccurate estimates of battery discharge and charge power limits by using a closed loop feedback control based on error between a battery voltage set point and commanded battery voltage.

Abstract: A method and system for controlling a solenoid-operated pressure regulator valve to achieve high compliance with respect to a commanded current in accordance with a precalibrated transfer function. A dither frequency imposed on applied current is changed at precalibrated regulated pressure values to avoid dynamic instability.

Abstract: A method for selectively adjusting an amount of fuel to an engine in a vehicle is provided. The vehicle includes an electric machine operatively connected to the engine and capable of controlling a speed of the engine. The method includes providing an amount of fuel to the engine based at least in part on a desired output of the engine, which is based at least in part on a driver input. The electric machine is commanded to control the engine speed based at least in part on the driver input. An output error of the engine is determined based at least in part on the command to the electric machine. The amount of fuel provided to the engine is adjusted when at least one predetermined condition is met, including the output error of the engine being greater than a predetermined amount.

Abstract: A method for inhibiting stalling of an engine of a hybrid electric vehicle. The method includes determining whether the engine is running, determining whether a gear ratio of a power transfer unit is selected, starting a timer, and implementing a stall mitigation strategy. The stall mitigation strategy is terminated when a predetermined period of time has elapsed.

Abstract: A system for heating a vehicle battery and a method for using the same. The system and method enable energy flow from the battery to a heater to heat the battery after determining a shut-down condition.

Abstract: A method for operating a hybrid vehicle when starting a power source. The method includes initiating a start sequence that includes driving the power source at a target speed, determining a speed adjustment value based on an amount of vehicle acceleration requested by the driver, adjusting the target speed, and modifying output of the electrical machine to maintain the target speed.

Abstract: The present invention provides an electronic module assembly with reduced EMI noise emission. The electronic module assembly of the invention includes an electronic module component that emits EMI noise. The electronic module assembly has a first electric reference region and a second electric reference region that is in communication with electronic module component. An impedance component is positioned in series with the first reference region and the second reference region such that impedance component attenuates the first electromagnetic noise signal. The electronic module assembly further includes low pass filter component that is in electrical communication with electronic module component. The present invention also provides a method of reducing EMI noise emission.

Abstract: A geared, power transmission mechanism for a hybrid electric vehicle wherein multiple power flow paths are established between an engine and vehicle traction wheels and between an electric motor and the vehicle traction wheels. At least one of the power flow paths is characterized by at least two ratios.

Abstract: A control system for a hybrid powertrain for a hybrid electric vehicle with an internal combustion engine and an electric drive system including an electric motor, a battery and a generator. The control system includes a system controller that monitors actual battery power in a closed-loop fashion and detects an error between actual battery power and a request for battery power. The engine power is corrected so that the battery is used at its intended level, thereby avoiding unnecessary charging and discharging.

Abstract: A method for controlling a wheel drive system of a hybrid electric vehicle when starting a power source. The hybrid electric vehicle includes first and second power sources, a motor, and a power transfer unit adapted to drive a vehicle wheel. The method includes determining whether the first power source is to be started, determining whether a level of torque requested by a vehicle operator is greater than a threshold value, maintaining a current gear ratio if the threshold value is exceeded, and providing a target level of torque to the power transfer unit.

Abstract: A system and method for diagnosing a potential electrical operating discrepancy in a polyphase electric motor by generating two independent torque estimates using a plurality of current sensors and, optionally, a shaft position sensor. Differences between the independent torque estimates are used to indicate potential discrepancies in electrical operating characteristics of the motor.

Abstract: The present invention can diagnose a potential discrepancy in electrical operating characteristics of a three phase electric motor by generating two independent torque estimates using a plurality of current sensors and a shaft position sensor. The invention provides a strategy to generate two independent torque estimates of a three phase electric motor comprising first and second systems to determine currents in two motor phases, first and second systems to generate a first and second estimate of motor shaft position, and first and second systems to generate first and second estimates of motor torque using the first and second systems to determine current in each motor phase and the first and second values of motor shaft position. The present invention detects also an electrical operating characteristic discrepancy in an electric motor-propelled vehicle's electrical components and subsystems, including single subsystem discrepancies between the two independent torque estimates.