Reconfigurable AC induction motor drive for battery-powered vehicle
AssigneeWestinghouse Electric Corp.
InventorColin D. Schauder
Life of this patent
Estimating the term…
Abstract
A drive system for a battery-powered vehicle is selectively operable in either a drive mode or an alternative battery-charging mode. In the drive mode, vector control circuitry is used to control instantaneous stator currents in an AC induction motor. The motor is preferably constructed having a pair of separately excitable three-phase windings spatially displaced by thirty electrical degrees. In the battery-charging mode, many of the same components are used to control battery charging current obtained as AC from a typical AC mains source.
Claims15
A reconfigurable battery-powered vehicle drive control selectively operable in either a drive mode to supply an AC induction motor or an alternative battery-charging mode, said control comprising:
- switching means for providing selective electrical interconnection to operate said control in a drive mode or an alternative battery-charging mode;
- reconfigurable inverter means connectable to at least one battery for operation in said drive mode to invert direct current from said battery to a polyphase alternating current to drive said motor, said inverter means further connectable in said alternative battery-charging mode to a source of AC energy for supplying charging current to said battery;
- firing circuit means for providing switching signals to operate said reconfigurable inverter means;
- a motor torque and flux controller operable in said drive mode to produce at least one drive reference vector signal and a slip angle signal;
- a battery-charging controller operable in said alternative battery-charging mode to produce at least two charging reference vector signals;
- and
- reconfigurable compensation means for processing signals from said controllers, said compensation means including differencing means for use in said drive mode to produce at least one drive error vector signal based on a difference between said at least one drive reference vector signal and a signal representative of actual conditions in said motor, said differencing means for use in said alternative battery-charging mode to produce at least two battery charging error signals based on a difference between said charging reference signals and signals representative of actual charging conditions, said compensation means further including compensators for receiving signals from said differencing means and producing control signals to operate said firing circuit means.
A battery-powered vehicle drive using an AC induction motor, said drive comprising:
- an AC induction motor having a pair of separately excitable polyphase windings mutually displaced by a predetermined angle;
- a motor torque and flux controller operable in a rotating reference frame to produce a pair of drive reference vector signals having a phase difference generally equal to said predetermined angle, said controller further producing a slip angle signal;
- first and second differencing circuits respectively producing first and second drive error vector signals based on a difference between said drive reference vector signals and signals representative of actual respective currents in said pair of polyphase windings;
- first and second compensators respectively compensating said drive error vector signals and producing output control signals, said compensators further comprising vector operators to transform said rotating reference frame to a stationary reference frame;
- first and second firing circuits respectively receiving said output control signals and producing first and a second switching signals;
- and
- first and second inverters connectable to at least one battery, said inverters respectively receiving said switching signals from said first and second firing circuits, said inverters further inverting direct current from said battery to polyphase alternating currents to respectively excite first and second windings of said pair of polyphase windings such that generally coinciding magnomotive forces are produced by said windings.
Dependencies are inferred from the claim text.