Traction integrated onboard dc charger

Abstract

An onboard DC charger for an electric vehicle, wherein the electric vehicle includes an electric machine and a power conversion device that is a drive circuit for the electric machine and a charging circuit for the on-board battery. The one or more electric machines of the vehicle are mounted to the body for providing locomotive energy, wherein the or each machine has a stator, a rotor mounted to the stator for rotation, and one or more windings; and a controller for operating in a first state and a second state wherein, in the first state, the controller allows current to be drawn from the DC energy source for energising at least one of the one or more windings such that the electric machine provides the locomotive energy and, in the second state, the controller controls the position of the rotor relative to the stator and allows at least one of the one or more windings to be energised to provide a charging current to the DC energy source.

1 . A vehicle, the vehicle comprising:
 a body;   a DC energy source mounted to the body;   a connector mounted to the body;   an electric machine mounted to the body, wherein the electric machine has a stator, a rotor mounted to the stator for rotation, and one or more windings;   a set of wheels;   a locking unit, wherein the locking unit restrains at least one of the rotor against rotation relative to the stator or the rotation of at least one wheel of the set of wheels of the vehicle; and   wherein, in a first state, a controller sends command signals to allow current to be drawn from the DC energy source for energising at least one of the one or more windings, and, in a second state, the controller sends command signals to position the rotor relative to the stator, engage the locking unit, and allow at least one of the one or more windings to be energised to provide a charging current to the DC energy source.   
     
     
         2 . The vehicle of  claim 1 , wherein the locking unit comprises a park brake, and wherein, in the second state, the controller sends command signals to actuate the locking unit to restrain the rotation of at least one wheel of the set of wheels. 
     
     
         3 . The vehicle of  claim 1 , wherein the locking unit includes at least one of the one or more windings. 
     
     
         4 . The vehicle of  claim 1 , wherein the vehicle includes a further electric machine having one or more windings, wherein the locking unit includes at least one of the one or more windings of the further electric machine. 
     
     
         5 . The vehicle of  claim 1 , wherein the locking unit includes a parking pawl, and in the second state, the controller actuates the locking unit to restrain the rotor against rotation relative to the stator. 
     
     
         6 . The vehicle of  claim 5 , wherein the electric machine includes a plurality of magnetic poles and when engaged, the parking pawl locks the rotor in alignment with at least one of the plurality of magnetic poles. 
     
     
         7 . The vehicle of  claim 2 , wherein the vehicle includes a decoupling unit for selectively decoupling the electric machine from the locking unit. 
     
     
         8 . The vehicle of  claim 7  wherein the set of wheels includes at least one wheel that is driven when the electric machine provides locomotive energy to the vehicle, and wherein the decoupling unit selectively decouples the electric machine from the at least one wheel. 
     
     
         9 . The vehicle of  claim 8 , wherein the decoupling unit includes a clutch. 
     
     
         10 . The vehicle of  claim 1 , wherein, in the second state, the locking unit locks the rotation of at least one wheel of the set of wheels, and the controller sends command signals to control the position of the rotor relative to a locked state of the at least one wheel. 
     
     
         11 . The vehicle of  claim 1 , wherein the vehicle includes a driveline which allows some torsional angular compliance or slip between the rotor and at least one wheel of the set of wheels. 
     
     
         12 . The vehicle of  claim 1 , wherein the vehicle includes a driveline which allows torsional angular compliance or slip between the rotor and the locking unit. 
     
     
         13 . The vehicle of  claim 1 , wherein the electric machine includes a plurality of magnetic poles and the controller, in the second state, sends command signals to position the rotor to align with at least one of the magnetic poles. 
     
     
         14 . The vehicle of  claim 1 , wherein the controller sends command signals to progress between the first and second state to control the position of the rotor relative to the stator. 
     
     
         15 . The vehicle of  claim 1 , wherein the electric machine includes a plurality of magnetic poles and the controller, when transitioning from the first state to the second state, sends command signals to align the rotor with at least one of the plurality of magnetic poles before engaging the locking unit. 
     
     
         16 . The vehicle of  claim 1 , wherein the controller, during the second state, sends commands to continuously control the position of the rotor relative to the stator. 
     
     
         17 . The vehicle of  claim 1 , wherein the controller uses the first state to stop the rotor in a beneficial alignment, such that when the controller sends command signals to the electric machine to transition to the second state, the rotor will be locked in the beneficial alignment by the locking unit. 
     
     
         18 . The vehicle of  claim 17 , wherein the electrical machine includes a rotor position sensor, and wherein the rotor position sensor is used to determine the alignment of the rotor. 
     
     
         19 . The vehicle of  claim 1 , wherein the electric machine has two or more sets of windings and the controller, in the second state, energises at least one of the two or more sets of the windings selectively to substantially or wholly counteract torque generated by the other of the two or more sets of windings. 
     
     
         20 . The vehicle of  claim 1 , wherein the vehicle includes at least two electric machines and wherein the controller sends command signals to control, during the second state, one of the at least two electric machines to substantially or wholly counteract a torque of the other of the at least two electric machines.