Abstract: Field oriented induction motor system including a field oriented induction motor having an associated torque current and an associated flux current and a predetermined current ratio, wherein the predetermined current ratio is defined as the ratio of the torque current to the flux current, and wherein the predetermined current ratio is dependent upon the saturation state of the motor. A method for selecting the ratio of torque current to flux current for a field oriented induction motor including applying an allocation factor to the torque current and flux current, wherein the allocation factor is dependent upon the saturation state of the motor. The saturation state of the motor is determined based upon motor parameters.

Abstract: Methods and related systems providing removal of heat from electric motors via fluid baths.

Abstract: A method and apparatus for improving the speed measurement quality in systems having multi-pole machines is taught. The method compensates for pole misalignment by moving average techniques.

Abstract: A device and method for detecting islanding of a grid connected inverter makes use of an injected white noise as a perturbing force on the output voltage of the inverter. The white noise is injected at least once in every cycle and can be generated at different rates in implementation. On loss of the grid, a frequency drift of the output voltage is detected and a positive feedback is activated that accelerates the drift.

Abstract: Systems and methods for controlling an induction motor including detecting a field weakening operation state of the motor, wherein the field weakening operation state is detected when a flux current, Id, in the motor is reduced to a predetermined fraction of its normal, non-voltage limited value. The systems and methods also including disabling an overmodulation operation state of the motor before said field weakening operation state is detected and enabling the overmodulation operation state of the motor after said field weakening operation state is detected.

Abstract: Fuel cell systems and control methods including a fuel cell and a second energy source, such as a battery that is adapted to supplement the fuel cell. In addition, the fuel cell system utilizes a single bipolar switching module, such as an IGBT six pack module that is configured to implement a DC/DC converter, such as a DC/DC boost converter, for both the fuel cell and the battery. The fuel cell system also makes use of a controller that is configured to control either or both of input current and output voltage of the DC/DC converter.

Abstract: A motor vehicle drive train assembly for achieving multiple effective ratios from a single ratio transaxle enables application of a fixed ratio transaxle, such as used in electric vehicle drive trains, to a multi-speed requirement, for example, in airport ground support equipment. Multiple configurations are enabled by varying the relative speed of the outputs through the differential of the transaxle, such as bringing one of the outputs to zero, or by using another motor to control the speed of one of the outputs.

Abstract: A device and method for detecting islanding operation of a static power source involves injection of a non-harmonic error on the phase angle of the static power source in regular steps to introduce a very small intentional phase shift for the output voltage of the static power source in every voltage cycle which is corrected in each cycle in synchronization with the grid voltage in normal operation of the grid. In abnormal operation of a grid loss, this intentional small phase shift or error causes an intentional small frequency drift in each voltage cycle that continues in one cycle after another cycle. When the intentional frequency drift is over a preset level, a detection circuit starts to isolate the static power source from the grid to prevent islanding operation.

Abstract: A power conversion system 10 which comprises a controller 12 and conversion assemblies 46, 48 which selectively rectify and invert an electrical signal. Conversion assemblies 46, 48 respectively comprise a plurality of integrated gate bipolar transistor assemblies. The power conversion system 10 is effective to convert DC current to AC current, convert AC current to DC current, and to control the output frequency of a received electrical signal to a conventional operating range.

Abstract: A method and system for detecting the negative sequence of three phase grid-connected inverter systems utilizes, for example, computer hardware and/or computer software to remove a direct current component from a direct-axis current feedback for a three phase current of the inverter system to yield a pure alternating current waveform signal. A first low pass filter eliminates high frequency noise from the alternating current waveform signal while passing a negative sequence signal. The filtered signal is rectified to an absolute value, and a second low pass filter flattens the rectified signal to an output signal that is indicative of the magnitude of the negative sequence current.

Abstract: A three-phase connector carries all three phases in one connector and keeps the phases properly isolated from each other and the motor case. The three-phase connector has metal connector components that are spaced from one another and supported in a nylon over molding covering each of the connector components, except for upper and lower exposed ends of the connector components, which are each drilled and tapped to receive bolts. First and second connector components extend above and below a flange of the three-phase connector with their respective exposed upper and lower ends offset in different planes than the exposed upper and lower ends of the third connector component.

Abstract: A rotor 33, 133 for use in an electrical machine 100 having permanent magnets 34, 134 included therein, each permanent magnet 34, 134 between an adjacent pair of poles 32, 132, wherein each adjacent pole 32, 132 has an opposite polarity. Each permanent magnet 34, 134 has a magnetization polarity on its radially-outward surface 38, 138, and each adjacent permanent magnet 34, 134 has the opposite polarity on its radially-outward surface 38, 138. In addition, each pair of permanent magnets 34, 134 have the same magnetic polarity on their adjacently facing surfaces. This arrangement of permanent magnets 34, 134 may be used on electrical machines 100 having either a Lundell-type rotor 33 or salient pole rotor 133. The arrangement of permanent magnets 34, 134 increases the output power and efficiency of the electrical machine 100 while decreasing magnetic noise.

Abstract: A control system for a permanent magnet motor having low-resolution speed measurement is taught. The control system is comprised of a speed regulator, voltage regulator and current regulator. The speed regulator uses a speed command and a measured speed for calculating a desired motor voltage; the voltage regulator uses a voltage command and an applied motor voltage for calculating a motor current command; and the current regulator uses a current command and a motor phase current for calculating a desired motor voltage for use by said voltage regulator; thereby providing a low resolution speed measurement to be used in a high performance application.

Abstract: A method and apparatus for controlling a permanent magnet synchronous motor (8) coupled to a turbo engine such that transient current and steady state current are minimized. The method comprises the steps of, for a given DC bus voltage, determining an acceleration profile as a function of a voltage-offset value, a low-speed rated speed value, a high-speed rated speed value, a first desired speed for warming up the turbo engine, and a second desired speed where the turbo engine has sufficient torque to accelerate to its rated speed without the aid of the permanent magnet synchronous motor (8).

Abstract: Integrated power systems and methods for use in an electric vehicle having a fuel cell and an electric motor, the integrated power systems and methods including a common casting, a traction inverter module operable for converting DC current generated by the fuel cell into AC current capable of powering the electric motor, and a DC/DC converter operable for stepping-down the voltage of the fuel cell. The traction inverter module and the DC/DC converter are disposed within the common casting.

Abstract: A method and apparatus for controlling a permanent magnet synchronous motor (8) coupled to a turbo engine such that transient current and steady state current are minimized. The method comprises the steps of, for a given DC bus voltage, determining an acceleration profile as a function of a voltage-offset value, a low-speed rated speed value, a high-speed rated speed value, a first desired speed for warming up the turbo engine, and a second desired speed where the turbo engine has sufficient torque to accelerate to its rated speed without the aid of the permanent magnet synchronous motor (8).

Abstract: A DC bus for use in a power module has a positive DC conductor bus plate parallel with a negative DC conductor bus plate. One or more positive leads are connected to the positive bus and are connectable to a positive terminal of a power source. One or more negative leads are connected to the negative bus and are connectable to a negative terminal of a power source. The DC bus has one or more positive connections fastenable from the positive bus to the high side of a power module. The DC bus also has one or more negative connections fastenable from the negative bus to the low side of the power module. The positive bus and negative bus permit counter-flow of currents, thereby canceling magnetic fields and their associated inductances, and the positive and negative bus are connectable to the center portion of a power module.

Abstract: In one embodiment, a harmonic feedback system is characterized by: a three-phase to two-phase transformer configured to convert an output fundamental frequency current from a distributed power system and to convert the output fundamental frequency current from a three-phase current to a two-phase stationary reference current; a harmonic frequency transformer configured to convert the two-phase stationary reference current to a synchronous reference current, said harmonic frequency transformer having a target synchronous reference frame frequency based upon a reference harmonic current of the output fundamental frequency current; at least one filter device configured to remove predetermined components from the synchronous reference current to output a harmonic feedback current; a summation component to compare the harmonic feedback current with the reference harmonic current and to output a harmonic error current for driving the distributed power system to produce the output current.

Abstract: This invention provides a process for determining a desired torque (load) value for a load-dependent current generating system, such as a fuel cell system, in an electric vehicle. The process calculates load based on various driver demands such as accelerator position, brake position, Key on/off, Gear selector position, and system component temperatures. Additionally, the process considers the amount of current available from the load-dependent current generating system and matches that current to the current drawn by the electric motor. The process can be applied to a direct current (DC) electric traction motor or an alternating current (AC) induction motor.