Abstract: A method of stopping an engine crankshaft includes selecting a target angular position at which the engine crankshaft is to be stopped and detecting an actual angular position of the engine crankshaft and a rotational speed of the engine crankshaft. A stopping torque in calculated based on the actual angular position of the engine crankshaft and the rotational speed of the engine crankshaft. The stopping torque is applied to the engine crankshaft via a motor/generator operably connected to the engine crankshaft. The engine crankshaft is stopped at the target angular position via the application of the stopping torque.

Abstract: An electric starter system is used with an engine. The starter system may include a solenoid device coupled to a pinion gear, a brushless starter motor connectable to the engine via the pinion gear during a requested engine start event, and a controller. In response to the start event, when the engine speed is less than a threshold speed, the controller delivers a control current to the solenoid device at a peak current level sufficient for translating the pinion gear into contact with the flywheel. The control current is reduced to a holding current level less than the peak current level after the pinion gear is engaged with the flywheel. Motor torque is commanded from the starter motor, through the pinion gear, and to the flywheel while maintaining the holding current level, and held for a duration sufficient for starting the engine.

Abstract: Presented are battery pack voltage-switching (“V-switch”) systems, methods for making/operating such systems, and multi-pack, electric-drive motor vehicles with battery pack V-switch capabilities. A method for controlling operation of a vehicle includes a vehicle controller receiving a voltage switch signal to change a voltage output of the vehicle's battery system. The vehicle controller determines if a speed of a traction motor is less than a calibrated base speed; if so, the controller transmits a pack isolation signal to a power inverter to electrically disconnect the traction battery packs from the traction motor. The vehicle controller determines if a bus current of a DC bus is less than a calibrated bus current threshold; if so, the controller transmits an open signal to open one or more pack contactor switches and a close signal to close one or more pack contactor switches thereby causing the vehicle battery system to output the second voltage.

Abstract: Systems, methods and motor-generators with preform windings and a molded core are described. The preform windings include a first end, a second end, and a plurality of in-slot portions extending from the first end to the second end. The molded core includes a plurality of slots. Each of the plurality of slots including a respective in-slot portion disposed therein. Each of the plurality of slots includes a wall conforming to an outer profile of the respective in-slot portion.

Abstract: Systems, methods, and devices including a rotor body including a curable material are described. The rotor body includes a plurality of ferromagnetic components arranged about an axis defining a circular periphery distal to the axis and a plurality of flux barriers. The plurality of ferromagnetic components define a plurality of channels arranged circumferentially about the axis. Each of the plurality of flux barriers includes a curable filler occupying a respective one of the plurality of channels. The curable filler is configured to maintain radial spacing of the plurality of ferromagnetic components and optimize mechanical stress across the rotor body.

Abstract: Methods of charging a vehicle battery pack are disclosed. Example methods may include determining a voltage imbalance between at least two parallel strings of a battery pack exceeds a threshold magnitude. Methods may further include electrically reducing the voltage imbalance between the at least two parallel strings using a series circuit including a first group of one or more of the battery cells of a first one of the parallel strings, and reconnecting the parallel strings in an electrical circuit in parallel to each other, in which configuration the strings of the battery pack may supply power to the vehicle.

Abstract: Presented are slotted permanent magnets (PM) for electric machines, motor generator units using slotted PMs, methods for making/using slotted PMs, and motor vehicles equipped with an electric traction motor using slotted PMs. An electric machine includes an annular stator with a hollow core and one or more internal stator slots. One or more electrically conductive windings is/are disposed in the stator slot(s). A cylindrical rotor is rotatably disposed inside the hollow core of the stator. One or more permanent magnets is/are mounted to the rotor. Each permanent magnet includes a rigid, single-piece PM body with opposing first and second faces. A first set of elongated grooves is recessed into the first face. An optional second set of elongated grooves is recessed into the second face. Each of the grooves has a depth that is substantially parallel to a direction of a magnetic field generated by the permanent magnet.

Abstract: Presented are slotted permanent magnets (PM) for electric machines, motor generator units using slotted PMs, methods for making/using slotted PMs, and motor vehicles equipped with an electric traction motor using slotted PMs. An electric machine includes an annular stator with a hollow core and one or more internal stator slots. One or more electrically conductive windings is/are disposed in the stator slot(s). A cylindrical rotor is rotatably disposed inside the hollow core of the stator. One or more permanent magnets is/are mounted to the rotor. Each permanent magnet includes a rigid, single-piece PM body with opposing first and second faces. A first set of elongated grooves is recessed into the first face. An optional second set of elongated grooves is recessed into the second face. Each of the grooves has a depth that is substantially parallel to a direction of a magnetic field generated by the permanent magnet.

Abstract: An apparatus for cooling an electric machine includes a plurality of fluid channels disposed in a first surface that surrounds at least part of the electric machine. Each of the plurality of fluid channels defines a circumferential path in the first surface, including a first channel section extending at least substantially parallel to first and second circumferences defined by ends of the electric machine, and including a second channel section configured to direct a cooling fluid between a central region of the first surface and an end region of the first surface. The apparatus also includes an outer shell configured to surround the first surface and define a fluid tight chamber between the first surface and the outer shell, the outer shell having at least one inlet through which the cooling fluid is introduced into the chamber and at least one outlet from which the cooling fluid exits the volume.

Abstract: An apparatus for flexible DC fast charging of an electrified vehicle includes a charge receptacle and a vehicle charging controller programmed to establish a wireless communication with a charging station. The apparatus further includes a reconfigurable energy storage system selectively and electrically connected to the charge receptacle. The reconfigurable energy storage system includes a first rechargeable energy storage device selectively and electrically connected to the charge receptacle, a second rechargeable energy storage device selectively connected to the charge receptacle, and a plurality of low-loss switching devices selectively connected to the first rechargeable energy storage device and the second rechargeable energy storage device.

Abstract: A method for operating an electromagnetic actuator includes an actuation event utilizing a current waveform for the actuator characterized by an initial peak pull-in current in a first direction of current flow when the actuator is commanded to an actuated position; and a reversed peak current in a second opposite direction of current flow applied after the actuator is commanded to a rest position. The reversed peak current has a magnitude that is greater than the magnitude of the initial peak pull-in current.

Abstract: An IPM electric machine includes a rotor, rotor shaft stator, and permanent magnets. The rotor includes rare earth permanent magnets disposed within pockets. The rotor, the pockets and the permanent magnets conform to a first set of geometric design parameters. The stator includes radially-inwardly projecting teeth that form slots between pairs of the teeth. Electrical windings are disposed within slots of the laminate stack. The teeth and slots conform to a second set of geometric design parameters. The quantity of slots is between 60 and 96, the quantity of electrical poles is between 6 and 12, the quantity of electrical phases is between 3 and 6 and the electrical windings include a quantity of turns per phase that is between 8 and 20. A ratio of an outer diameter of the stator to an active length of the rotor is between 2 and 3.5.

Abstract: A vehicle propulsion system includes an engine configured to be selectively activated to provide torque to propel the vehicle and a starter module coupled to the engine and configured to start the engine from an inactive state. The starter module includes a brushless electric machine to generate an output torque to crank start the engine. The starter motor also includes a pinion gear coupled to the electric machine, where the pinion gear is actuatable to selectively engage a cranking input of the engine. A controller assembly is programmed to cause actuation of the pinion gear to engage the cranking input of the engine and transfer a cranking torque to activate the engine.

Abstract: A starter includes a three-phase switched reluctance electric motor including a rotor and a stator, a pinion gear, a power inverter that is connected to the stator, and a rotational position sensor. The rotor includes a quantity of rotor poles that is between 6 and 16, and the stator includes a quantity of stator poles that is between 8 and 24. An outer diameter of the electric motor is less than 85 mm. An active length of the motor is less than 50 mm. An airgap distance between the rotor and the stator is between 0.1 mm and 0.5 mm. A ratio between a rotor pole arc and a stator pole arc is at least 1.0:1. A ratio between a stator diameter and a rotor diameter is at least 2.0:1, and a ratio between a stator pole height and a rotor pole height is at least 2.5:1.

Abstract: A solenoid assembly includes a solenoid actuator having a core. A coil is configured to be wound at least partially around the core such that a magnetic flux (?) is generated when an electric current flows through the coil. An armature is configured to be movable based on the magnetic flux (?). A controller has a processor and tangible, non-transitory memory on which is recorded instructions for controlling the solenoid assembly. The controller is configured to obtain a plurality of model matrices, a coil current (i1) and an eddy current (i2). The magnetic flux (?) is obtained based at least partially on a third model matrix (C0), the coil current (i1) and the eddy current (i2). Operation of the solenoid actuator is controlled based at least partially on the magnetic flux (?). In one example, the solenoid actuator is an injector.

Abstract: An interior permanent magnet electric machine includes a stator having a plurality of teeth disposed around a circumference oriented radially towards a center defining slots interposed between each of the teeth, and a conductive winding wrapped around at least one of the teeth of the stator to receive an electrical current. The electric machine also includes a rotor which is rotatable relative to the stator. The rotor defines a plurality of openings configured to hold permanent magnets near an outer portion of the rotor and a number of spokes interposed between mass reduction cutouts located closer to a center of the rotor relative to the permanent magnets. Each of the permanent magnets defines a magnetic pole and each of the spokes is circumferentially aligned with one of the magnetic poles.

Abstract: Methods of charging a vehicle battery pack are disclosed. Example methods may include determining a voltage imbalance between at least two parallel strings of a battery pack exceeds a threshold magnitude. Methods may further include electrically reducing the voltage imbalance between the at least two parallel strings using a series circuit including a first group of one or more of the battery cells of a first one of the parallel strings, and reconnecting the parallel strings in an electrical circuit in parallel to each other, in which configuration the strings of the battery pack may supply power to the vehicle.

Abstract: An apparatus for flexible DC fast charging of an electrified vehicle includes a charge receptacle and a vehicle charging controller programmed to establish a wireless communication with a charging station. The apparatus further includes a reconfigurable energy storage system selectively and electrically connected to the charge receptacle. The reconfigurable energy storage system includes a first rechargeable energy storage device selectively and electrically connected to the charge receptacle, a second rechargeable energy storage device selectively connected to the charge receptacle, and a plurality of low-loss switching devices selectively connected to the first rechargeable energy storage device and the second rechargeable energy storage device.

Abstract: A multi-phase switched reluctance motor including a rotor and a stator, an electronic commutator subassembly, and a controller. The electronic commutator subassembly includes an electronic motor control unit, a power inverter, and a rotational position sensor, with the power inverter being electrically connected to the stator of the switched reluctance motor. The controller is in communication with the electronic motor control unit, the power inverter, and the rotational position sensor. The controller includes an instruction set that is executable to characterize operation of the switched reluctance motor, dynamically determine inductance of the switched reluctance motor based upon the characterized operation, and execute a closed-loop torque control routine to control the switched reluctance motor based upon the dynamically determined inductance of the switched reluctance motor.

Abstract: A starter system includes a brushless electric starter motor and a battery power pack, the motor operatively connectable to an internal combustion engine of a powertrain. A power inverter converts direct current provided from the battery power pack to multi-phase alternating current to drive the motor. A pinion gear with one-way clutch is rotatably driven by the motor and movable between a disengaged position and an engaged position in which the pinion gear is meshingly engaged with a ring gear operatively connected to a crankshaft of the engine. A solenoid is operatively connected to the pinion gear. An electronic control system controls the motor to crank the engine using power provided from the battery power pack, and to separately command the solenoid to a disabled or an enabled state. A method of controlling the starter system controls the motor to crank the engine in a restart following an autostop.