Abstract: A system for controlling a brushless motor includes drive circuitry in communication with the brushless motor and a primary control device in communication with the drive circuitry. The system also includes a secondary control device in communication with the drive circuitry and a multiplexer for selectively providing an output of the primary control device or an output of the secondary control device to the drive circuitry, wherein the output of the primary control device is provided to the drive circuitry when the primary control device is operating normally.

Abstract: An induction motor control device includes an inverter circuit for driving an induction motor by outputting a command voltage, a current detector for detecting an output current, a magnetic flux estimation observer for generating an estimated magnetic flux, an estimated current, and a phase command for the motor using the command voltage and the output current, a primary angular speed estimator for estimating a primary angular speed using the estimated magnetic flux, a slip compensator for calculating a slip angular frequency using the output current, a first angular speed estimator for estimating a first angular speed using the primary angular speed and the output current, a second angular speed estimator for estimating a second angular speed using the output current, the estimated magnetic flux, and the estimated current, and a resistance estimator for estimating a secondary resistance value of the motor using the first and second angular speeds.

Abstract: An inverter apparatus for converting a DC power converted from an input AC power to an output AC power of a variable frequency and a variable electric power to drive an induction motor at a variable speed. The inverter apparatus includes a rectifying unit, a filter capacitor, an inverter unit having an input connected across the filter capacitor, an input current detector and a gate circuitry for driving the inverter unit. An excitation current detection unit detects an excitation current of the induction motor from an output signal of the input current detector, a gate signal for driving the gate circuitry and a reference phase command. A setting unit sets a limitation level of the excitation current, a torque boost voltage command unit produces a torque boost voltage command, and a torque boost voltage compensation unit changes the torque boost voltage command so that the detected excitation current value is smaller than or equal to the limitation level.

Abstract: An exemplary embodiment of the invention is a method for detecting a potentially locked axle on a vehicle propelled by an AC motor. The method includes conducting a speed test by estimating axle speed and comparing estimated axle speed to measured vehicle speed. The existence of a potential locked axle condition is determined based on the comparing of estimated axle speed to measured vehicle speed. Additional tests are disclosed for determining a potential locked axle condition and a sensor fault condition.

Abstract: A device for high efficiency motor control includes an induction motor and a controller. The induction motor generates a motor torque and has a given rotor resistance and magnetizing inductance at a specific temperature. The controller is coupled to and controls the induction motor. The controller includes control logic operative to maximize the motor torque using a flux current and a torque current. The controller determines the flux current and torque current based upon a requested torque, a requested speed, the magnetizing inductance, the temperature and the rotor resistance.

Abstract: An electrical system that receives power from an external power source that includes an inverter (U1). The inverter (U1) receives DC power and generates a variable voltage output. First and second current collectors (30, 32) connected to the inverter (U1) and receive the DC input through contact with positive and negative poles of the external power source. A motor (M1) and an internal DC bus (+,-) are connected to the current collectors (30,32). A protection circuit is connected across the internal DC bus (+,-), and protects the inverter (U1) from connection to an input of improper polarity. The protection circuit permits the inverter (U1) to deliver a DC output to the power source during a regenerative braking operation.