Abstract:
A vehicle includes a propulsion system having multiple electric motors. A battery system is connected to the electric motors via a direct current to direct current (DC-DC) converter and an inverter. The battery system includes a battery assembly having a plurality of battery modules. Each of the battery modules has multiple individual battery cells arranged in battery packs, a set of sensors configured to monitor a set of parameters of each battery pack, and a plurality of battery pack mounts. Each battery pack mount includes a base plate and a top plate and an actuator configured to alter a distance between plates. A monitoring unit is configured to monitor a value representative of a battery pack pressure, determine whether the value falls within a pressure threshold window, and maintain the value within the pressure threshold window by actively altering the battery pack pressure.
Abstract:
A vehicle includes a propulsion system having multiple electric motors. A battery system is connected to the electric motors via a direct current to direct current (DC-DC) converter and an inverter. The battery system includes a battery assembly having a plurality of battery modules. Each of the battery modules has multiple individual battery cells arranged in battery packs, a set of sensors configured to monitor a set of parameters of each battery pack, and a plurality of battery pack mounts. Each battery pack mount includes a base plate and a top plate and an actuator configured to alter a distance between plates. A monitoring unit is configured to monitor a value representative of a battery pack pressure, determine whether the value falls within a pressure threshold window, and maintain the value within the pressure threshold window by actively altering the battery pack pressure.
Abstract:
Aspects of the disclosure include the detection of battery cell degradation. An exemplary battery management system can include a memory, computer readable instructions, and one or more processors that perform operations that include: responsive to determining that a charging state has completed, measuring a first cell voltage of a cell of the battery pack; responsive to the first cell voltage exceeding a reference voltage, measuring a second cell voltage of the cell of the battery pack; responsive to the second cell voltage being equal to the reference voltage, measuring a cell pressure of the cell of the battery pack at the reference voltage; determining a difference between the cell pressure and a prior cell pressure at the reference voltage; and responsive to the difference between the cell pressure and the prior cell pressure exceeding a threshold, identifying the cell of the battery pack as a degraded cell.
Abstract:
A method of transient control for enrichment operation in a low-temperature combustion engine. The method includes determining if a current mode of the low-temperature combustion (LTC) engine is a positive valve overlap (PVO) mode. Determining if a previous mode of the LTC engine was also the PVO mode when the current mode is the PVO mode, wherein the previous mode is immediately prior to the current mode. Determining if the previous mode of the LTC engine was a negative valve overlap (NVO) mode when the previous mode was not the PVO mode. Initiating a predetermined enrichment PVO mode for the LTC engine based on the previous mode of the LTC engine. The predetermined enrichment PVO mode includes initiating a deep enrichment PVO mode, when the previous mode of the LTC engine was the NVO mode, and initiating a shallow enrichment PVO mode, when the previous mode of the LTC engine was not the NVO mode.
Abstract:
A method of controlling pre-primary ignitions of an internal combustion engine includes accessing data corresponding to an exhaust gas recirculation error and data corresponding to at least one of a rotational speed of the engine, a throttle position of a throttle, and a combustion mode of the engine. A voltage of the electrical power to be applied to an ignition source and a number of pre-primary ignitions to be applied are calculated based on the data corresponding to the exhaust gas recirculation error and the data corresponding to at least one of the rotational speed of the engine, the throttle position, and the combustion mode of the engine.
Abstract:
An internal combustion engine is configured to operate in a homogeneous-charge compression-ignition combustion mode. A method for operating the internal combustion engine includes determining a desired effective charge dilution for a cylinder charge for a cylinder firing event. A desired air/fuel ratio, a desired intake air mass and a desired intake oxygen are determined to achieve the desired effective charge dilution for a combustion event. The desired air/fuel ratio is adjusted based upon a difference between the desired intake oxygen and the actual intake oxygen, and engine operation is controlled to achieve the adjusted desired air/fuel ratio.
Abstract:
The method can control a powertrain in order to maintain the charge temperature at a desired value regardless of exhaust manifold pressure or altitude. The method includes the following steps: (a) receiving a torque request; (b) determining a desired air charge based, a least in part, on the torque request; (c) determining an actual air charge based, at least in part, on input signals from a manifold absolute pressure (MAP) sensor and a mass airflow (MAF) sensor; (d) adjusting an intake valve timing of the intake valve such that the actual air charge is equal to a desired air charge, and (e) adjusting throttle position and actuator positions of boosting devices such that the actual intake manifold pressure is equal to the desired intake manifold pressure.