A locomotive, a first chopper circuit, and a second chopper circuit integrating a traction motor with an energy storage device are disclosed. The locomotive includes a prime mover, an energy management device, a DC power bus, a traction motor, an energy storage device, a resistor grid, and a chopper circuit. Each chopper circuit is controlled by the energy management device and includes a plurality of power semiconductors with variable switching frequency. The traction motor may be capable of operating in a motoring mode, where power is controllably supplied by either the prime mover and/or the energy storage device; and a dynamic braking mode, where generated power is controllably allocated to the energy storage device and/or the resistor grid.

A locomotive, a first chopper circuit, and a second chopper circuit integrating a traction motor with an energy storage device are disclosed. The locomotive includes a prime mover, an energy management device, a DC power bus, a traction motor, an energy storage device, a resistor grid, and a chopper circuit. Each chopper circuit is controlled by the energy management device and includes a plurality of power semiconductors with variable switching frequency. The traction motor may be capable of operating in a motoring mode, where power is controllably supplied by either the prime mover and/or the energy storage device; and a dynamic braking mode, where generated power is controllably allocated to the energy storage device and/or the resistor grid.

A controller is installed in a vehicle. The vehicle includes an engine, rotary electric machine for power generation, rotary electric machine for propulsion, power storage device, inverter for power generation, and inverter for propulsion. The controller includes a drive control changing unit that changes drive control of at least one of the rotary electric machine for power generation and the rotary electric machine for propulsion, for reduction of a total value of a power-generation-side ripple current generated according to an operating state of the rotary electric machine for power generation, and a drive-side ripple current generated according to the operating state of the rotary electric machine for propulsion, when the total value is equal to or larger than a preset threshold value.

A direct current traction motor control system includes plural motors of with each of the motors configured to be coupled with a different axle of a vehicle and to rotate the axle to propel the vehicle. The motors are coupled with a DC bus and configured to receive DC via the DC bus to power the motors. The system also includes plural switch assemblies with each of the switch assemblies having an H-bridge circuit coupled with a different motor of the motors to control rotation of the motor. The system includes a controller configured to communicate control signals to the switch assemblies to individually control the H-bridge circuits to control one or more of torques output by the motors or rotation directions of the motors.

A method of controlling an electric motor to optimize system efficiency of an electric motor operable in a pulsed mode and a continuous mode is disclosed herein. The method includes receiving a requested torque for the electric motor, calculating a pulsed system efficiency, calculating a continuous system efficiency, and operating the electric motor in the pulsed mode when the pulsed system efficiency is greater than the continuous system efficiency. The pulsed system efficiency is calculated for delivering the requested torque from the electric motor in a plurality of torque pulses greater than the requested torque. The continuous system efficiency is calculated for delivering the requested torque from the electric motor as a continuous torque. The system efficiency may be at least partially based on a battery efficiency and a motor efficiency.

A method of controlling an electric motor to optimize system efficiency of an electric motor operable in a pulsed mode and a continuous mode is disclosed herein. The method includes receiving a requested torque for the electric motor, calculating a pulsed system efficiency, calculating a continuous system efficiency, and operating the electric motor in the pulsed mode when the pulsed system efficiency is greater than the continuous system efficiency. The pulsed system efficiency is calculated for delivering the requested torque from the electric motor in a plurality of torque pulses greater than the requested torque. The continuous system efficiency is calculated for delivering the requested torque from the electric motor as a continuous torque. The system efficiency may be at least partially based on a battery efficiency and a motor efficiency.

An illustrative dual power inverter module includes a detection circuit configured to detect loss of low voltage DC electrical power supplied to a controller for a first power inverter and a second power inverter of a drive unit for an electric vehicle. A first backup power circuit is associated with the first power inverter and a second backup power circuit is associated with the second power inverter. Each backup power circuit is configured to convert high voltage DC electrical power to low voltage DC electrical power responsive to detection of loss of low voltage DC electrical power supplied to the controller. Three-phase short circuitry is configured to apply a same fault action to the first power inverter and the second power inverter responsive to detection of loss of low voltage DC electrical power supplied to the controller, wherein the same fault action includes applying equalized torque to each axle operatively coupled to the drive unit.

An illustrative dual power inverter module includes a detection circuit configured to detect loss of low voltage DC electrical power supplied to a controller for a first power inverter and a second power inverter of a drive unit for an electric vehicle. A first backup power circuit is associated with the first power inverter and a second backup power circuit is associated with the second power inverter. Each backup power circuit is configured to convert high voltage DC electrical power to low voltage DC electrical power responsive to detection of loss of low voltage DC electrical power supplied to the controller. Three-phase short circuitry is configured to apply a same fault action to the first power inverter and the second power inverter responsive to detection of loss of low voltage DC electrical power supplied to the controller, wherein the same fault action includes applying equalized torque to each axle operatively coupled to the drive unit.

An electric powered vehicle includes: a motor; an inverter configured to convert electric power from a battery to drive the motor; a transmission configured to shift the rotation output of the motor at a variable transmission gear ratio; and a controller configured to control the inverter to control the driving of the motor and to control a change in the shift gear stage, and to perform high surge region avoidance control for changing the gear ratio of the transmission to change a motor rotation speed while maintaining a vehicle speed and changing an operation point outside a high surge region, when the operation point of the motor enters the high surge region where the inverter is controlled by a PWM overmodulation control system, and the high surge region is defined to be equal to or higher than a predetermined rotation speed and equal to or less than predetermined torque.

A method for operating switching elements of an inverter of a vehicle that is driven by way of a three-phase synchronous machine. The inverter has a series circuit of switching elements for the phases. When the vehicle brakes, the synchronous machine is used to set a cycle rate for the operation of the switching elements depending on a frequency of AC phase currents of the synchronous machine. The electrical energy provided by the synchronous machine is fed to a DC voltage intermediate circuit. The cycle rate is set according to the frequency of the AC phase currents, such that it corresponds to the frequency of the respective AC phase currents of the synchronous machine. Zero points of the AC phase currents are determined, and the switching elements are operated to set a predefined phase difference between the respective AC phase current and a respectively associated AC phase voltage.