Gm Global Technolgoy Operations, Inc.

Abb Inc.

Other

Abb Oy

Abb Schweiz Ag

Itt Automotive Electrical Systems, Inc.

Kalyan P Gokhale

Douglas W Karraker

Nicklas Jan Anders Sodo

Thaddeus Schroeder

Samuli J Heikkil&auml;

Alpo K Vallinmäki

Chandra S Namuduri

Sam Raghuma Reddy

Donald J Truettner

Matti T Jussila

Dennis Tyczkowski

Ilkka T Pajari

Alpo K Vallinm&auml;ki

Jeffrey A Brunner

Dennis L Mueller

A detection circuit including a converter configured to convert a multiphase alternating current (AC) input into a direct current (DC) output, a plurality of sensing diodes, each sensing diode being separately electrically connected to one phase of the multiphase AC input, at least one node arranged downstream from the plurality of sensing diodes relative to the multiphase AC input, a power source configured to output a power source voltage to the at least one node and plurality of sensing diodes, and a mask time generator configured to determine a node voltage at the at least one node and determine whether the node voltage persists for a predetermined mask time period.

Detection of ac input disconnection in an AC-DC converter section of a power converter

A system for the detection of welded contacts in a circuit of a line converter system has a plurality of inverter switches, a plurality of utility switches in which a pair of utility switches is connected in series through a line to a utility, a voltage detector, an electronic controller, and a DC input source. The line converter system converts incoming DC power into AC output power that is delivered to the utility grid. The voltage detector measures the voltage across a first node and a second node of the circuit and provides an output that is interpreted by an electronic controller for each step performed during a method of detection of welded contacts. The detection method has a sequence of test steps in which at least one switch is opened and/or closed, a DC bus of the inverter or the utility grid is used as a stimulus voltage, and the voltage is measured. If a voltage is not detected across the first and second nodes, the test sequence is continued until a welded contact is detected or the electronic controller determines that none of the contacts are welded. If the controller determines that none of the contacts are welded, the line converter system is permitted to connect and supply AC power to the utility.

Detection of welded switch contacts in a line converter system

A motor bypass is controlled by a digital signal processor (DSP) with embedded control software that allows fault detection and annunciation, serial communications between both a variable frequency drive (VFD) and a bypass controller and the bypass controller and a host computer. The use of the DSP and embedded control software further allows for contactor coil control to provide fault tolerant operation as well as fault condition detection and annunciation to the user.

AC motor bypass with fault annunciation, serial communication and fault tolerant coil control

Non-linear inductor(s) are used to reduce the percent total harmonic distortion of the harmonics in the line currents in the input side rectifier system of an ac drive system. Several constructions for the non-linear inductor(s) are described. The non-linear inductor(s) may be constructed from E and I laminations. The gap depends on the construction of the middle leg of the E laminations and may have a step with a constant spacing or a variable spacing which depends on the stacking of the laminations. Alternatively the non-linear inductor(s) may be constructed from a toriodal core that either has a step gap or a variable type gap.

Low harmonic rectifier circuit

Method for making a non-linear inductor

The direct torque control (DTC) principle is used to control the torque of a wound ring rotor slip induction machine, also known as a doubly fed or cascade machine, by utilizing a solid state inverter on the rotor side. In addition, the DTC principle is used to control the power factor at the stator terminals of the doubly fed machine to a desired level and also to perform the task of synchronization of stator voltage to the grid voltage. An integrated controller is used to implement these three functions.

Controller for a wound rotor slip ring induction machine

A method for minimizing torque ripple in a permanent magnet brushless DC motor includes the steps of energizing a first winding of the motor to generate a first current, energizing a second winding of the motor to generate a second current, and overlapping the first and second currents in time by a preselected time to reduce torque ripple. The structure for performing the method includes conventional brushless DC motor drive circuitry responsive to a motor rotor position signal, and a speed control signal, to sequentially generate a gate drive signal for driving a respective semiconductor switch to energize each winding of the motor. The structure further includes a phase overlapping circuit interposed between the conventional brushless DC motor control circuitry output and the semiconductor switches used to energize each winding of the motor. The phase current overlap circuit includes a monostable multi-vibrator for generating a 'one-shot.' The pulse width or duration of the 'one-shot' determines the extent of the phase current overlap. The overlapping circuit detects transitions on the gate drive signal lines, and in response generates a trigger signal. The trigger signal triggers generation of the 'one-shot.' The overlapping circuit maintains two of its gate drive signals for the duration of the 'one-shot.'

Method and apparatus for minimizing torque ripple in a DC brushless

An apparatus for use in diagnosing an evaporative emission canister collection and purge system. An EVAP system of a vehicle is diagnosed through the use of a mechanism wherein a change in conductivity occurs in response to a change in concentration of fuel vapor in the variably conductive mechanism. By sensing the change in conductivity, a diagnostic mechanism determines whether the vapor collection and purge systems are operating correctly.

Conductive foam vapor sensing

A method and apparatus for electrically exciting a magneto-resistor (MR) device that is adapted to sense variations in a magnetic field. Electric current is delivered to flow through the MR device and produce a voltage drop across the resistance the MR device, where the voltage drop varies in accordance with changes in the flux density of the sensed magnetic field. The current flowing through the MR device is limited to a predetermined maximum current value to prevent damage to the MR device due to self heating at elevated operating temperatures. When the delivered current is less than the predetermined maximum current value, the current flowing through the MR device is controlled to maintain a measured characteristic of the voltage drop appearing across the MR device at a desired value. This increases the sensitivity of the MR device over its operating temperature range to variations in the sensed magnetic field. In one embodiment, the delivered current is controlled to maintain the peak voltage appearing across the resistance of the MR device at a desired peak value. In another embodiment, the delivered current is controlled to maintain the average voltage appearing across the MR device at a desired average value.

Method and apparatus for electrically exciting a magneto-resistor device

A signal conditioning circuit which converts multiple analog signals received from an encoder into a multi-bit digital signal, corresponding to the angular position of a rotary object, which is independent of any common mode disturbances such as temperature, humidity, ambient light and aging. At any given time, at least one of the analog signals is at a maximum voltage and at least one of the analog signals is at a minimum voltage. At no time are all of the analog signals simultaneously at a maximum or simultaneously at a minimum. The signal conditioning circuit continuously detects the maximum and minimum values of the analog signals. A midpoint of the maximum and minimum values is determined and compared with the original analog signals. For all values of the analog signals greater than the midpoint value, a binary logic level of 1 is outputted. For all values of the analog signals less than the midpoint value, a binary logic level of 0 is outputted. There is one comparator and corresponding binary output for each analog signal. In combination, the comparators form the necessary multi-bit digital signal.

Multi-bit encoder signal conditioning circuit having common mode

A controller for a multi-phase brushless DC motor which pulse width modulates the switching devices of a bridge controller, thereby energizing the phase windings of the motor in such a manner as to eliminate current flow in the inactive phase windings. The bridge switching devices are modulated over distinct segments of the total conduction time. A pattern of modulation, constant conduction, and modulation is established which allows circulating current to flow only through active phase windings, effectively eliminating any undesirable braking torque resulting from current flow through inactive phase windings which lowers the overall motor efficiency.

Pulse width modulation control apparatus and method

An ignition system for a spark ignited internal combustion engine has a plurality of high voltage switches connected respectively between a source of spark plug firing voltage and the spark plugs of the engine. Each high voltage switch includes a plurality of series connected light sensitive controlled rectifiers. The controlled rectifiers are associated with light emitting diodes which are positioned to apply light energy to the controlled rectifiers. When light energy is applied to a controlled rectifier, it is biased or gated conductive. The system is arranged such that all of the controlled rectifiers are biased conductive before the spark plug firing voltage is developed. A high voltage switch can be formed by mounting the controlled rectifiers on a substrate. The light emitting diodes are positioned such that the light emitted from one diode is applied to a plurality of controlled rectifiers.

Ignition system having an electronic distributor

An ignition system for a spark ignited internal combustion engine. The system can apply alternating current to the electrodes of a spark plug to maintain an arc at the electrodes for the desired length of time. The amplitude of the arc current can be varied. The alternating current is developed by a DC to AC inverter that is comprised of a transformer that has a center tapped primary and a secondary that is connected to the spark plug. An arc is initiated at the spark plug by discharging a capacitor through one of the winding portions of the center-tapped primary. Alternatively, the energy stored in an inductor can be supplied to a primary winding portion to initiate an arc. The ignition system is powered by a controlled current source that receives input power from a source of direct voltage such as a battery on a motor vehicle.

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New Berlin, WI, United States of America

Kalyan P Gokhale