General Electric Company

Albert Andreas Esser

James Patrick Lyons

Lyle Thomas Keister

Gerald Burt Kliman

Paul M Espelage

Vlatko Vlatkovic

Lee Burton Silverthorn

William James Premerlani

Paul S Bixel

Paul Michael Szczesny

Steven Wade Sutherland

Rudolph A Koegl

Howard Ross Edmunds

Jeffrey Joseph Nasadoski

Peter Claudius Sanza

Paul Stephen Pate

Stephen Daniel Nash

Robert Joseph Bastian

David Jeremiah Hoeweler

Yifan Zhao

Fei Fred Wang, Sr

Conrad Angelo Pecile

Patrick Henry McGinn

Melvin La Hughes

Mark Gerald Adamiak

A method for obtaining a power system phasor includes sampling a power system signal at instants determined by a nominal power system frequency to provide a plurality of data samples; using the data samples to estimate a phasor having an elliptical trajectory; generating a deviation formula representing a frequency deviation between actual and nominal power system frequencies; and using the deviation formula to perform a coordinate transform of the estimated phasor to provide a scaled phasor having a substantially circular trajectory. If the data samples are unevenly spaced, a method in another embodiment includes minimizing squares of errors between the unevenly spaced data samples and an approximating sinusoidal function of the data samples. Power system phasors can be used to detect turn faults by providing scaled current and voltage phasors; extracting fundamental voltage and current phasors; and applying a symmetrical component transform to the fundamental voltage and current phasors to obtain symmetrical component voltage and current phasors for use in determining the existence of a turn fault. Variance calculations and/or trigonometric function fits can be used to increase sensitivity of fault detection.

Method and apparatus for compensation of phasor estimations

A fixture to evaluate stator production quality is placed about a stator core so as to introduce a test winding about the stator without need for hand winding. The fixture includes an inner annulus and an outer annulus each with axial conductors thereon, and top and bottom plates each with conductors thereon. The core is fitted between the inner and outer annuli, and between the top and bottom plates. The inner axial conductors and outer axial conductors are connected to one another at their lower ends through the bottom plate conductors and at their upper ends through the top plate conductors. Once testing is complete, the fixture is easily removed.

Method and fixture for evaluating stator core quality in production

A high power motor drive converter includes: a five level hybrid NPC output power conversion stage including three NPC phase bridges having switches and coupled in a wye configuration through a converter neutral point, each NPC phase bridge receiving power on a respective direct current bus; three isolated split series-connected DC capacitor banks each coupled in parallel to a respective one of the three NPC phase bridges; and a controller for selecting switch positions with active control of neutral voltages. The controller is adapted to select switch positions using feedforward sine-triangle modulation with third harmonic injection, zero sequence injection, and/or discontinuous modulation injection.

Five level high power motor drive converter and control system

A system for temperature control of an electronic component includes a heat plate supporting the component; a heat plate temperature sensor; a fan capable of providing air for cooling the heat plate; and a fan control for using the heat plate temperature to control the operation of the fan to provide a substantially constant heat plate temperature. The system can further include a heat pipe assembly having fins and coupled to the heat plate with the fan capable of providing air to the fins. The heat pipe assembly can include at least two heat pipes each having first ends coupled to the heat plate and second ends situated in a condensation section where at least one of the heat pipes has a different working fluid than an other. A switch temperature or load current sensor can be coupled to the heat plate and supply data to a switch controller for receiving the switch temperature, determining whether the temperature or load current has changed, and adjusting a switching frequency of the at least one electronic switch device in response to any change of the switch temperature. A bus layer can be situated adjacent the component and selectively coated with an insulating material and studs can mechanically and electrically coupling the bus layer and a printed circuit board to the component. An insulating shield can be situated between the bus layer and the printed circuit board with the studs.

Temperature control of electronic components

A high power motor drive converter includes a three level neutral point clamped (NPC) output power conversion stage including switches; a split series connected DC capacitor bank coupled in parallel with the NPC output power conversion stage; and a controller for selecting switch positions for controlling the NPC output power conversion stage and controlling a neutral voltage balance of the DC capacitor bank by using space vector modulation and predictive charge calculations.

High power motor drive converter system and modulation control

Stored rotational energy in an operating variable speed wind turbine is used to pitch blades and brake the wind turbine in the event of utility power grid failure. In one embodiment, a generator IGBT converter and the main power utility grid IGBT converter supply control and pitch servo power during turbine deceleration, and a ride-through capacitor on a DC emergency power supply bus and the main DC link capacitor provide additional energy storage. In another embodiment, a step-down DC/DC power converter adds to the intermediate DC link of the power conversion system with the secondary of the step down converter powering both the hub pitch controller and the wind turbine control system.

Method and system for wind turbine braking

A power device control system includes a power device having an input gate and first and second output terminals, a controller, and a gate driver for supplying current to the input gate of the power device, comparing a voltage difference between the first and second output terminals, and providing a comparator signal to the controller if the voltage difference is greater than or equal to a predetermined maximum voltage difference. The controller is capable of providing a command signal to the gate driver and pulse width modulating the command signal upon receiving a comparator signal from the gate driver to gradually switch off the power device. The control system can further include a current sensor coupled between one of the first and second output terminals and the controller for supplying a current signal and an integrated current signal to the controller. The control system can be capable of variably pulse width modulating the command signal, and, in one embodiment, the modulation process includes varying on/off switching of the command signal to increase a percentage of off time during subsequent periods of modulation.

Gate voltage modulation for transistor fault conditions

A bidirectional buck boost converter and method of operating the same allows regulation of power flow between first and second voltage sources in which the voltage level at each source is subject to change and power flow is independent of relative voltage levels. In one embodiment, the converter is designed for hard switching while another embodiment implements soft switching of the switching devices. In both embodiments, first and second switching devices are serially coupled between a relatively positive terminal and a relatively negative terminal of a first voltage source with third and fourth switching devices serially coupled between a relatively positive terminal and a relatively negative terminal of a second voltage source. A free-wheeling diode is coupled, respectively, in parallel opposition with respective ones of the switching devices. An inductor is coupled between a junction of the first and second switching devices and a junction of the third and fourth switching devices. Gating pulses supplied by a gating circuit selectively enable operation of the switching devices for transferring power between the voltage sources. In the second embodiment, each switching device is shunted by a capacitor and the switching devices are operated when voltage across the device is substantially zero.

Bidirectional buck boost converter

An active damping control device for an active power filter includes a filter circuit having an inductor and a capacitor for suppressing noise in the active power filter; a first current sensor for sensing a three phase capacitor current of the filter capacitor; a second current sensor for detecting a three phase load current; and an active power filter controller for extracting the fundamentals of the capacitor and load currents and calculating a reference current for the active power filter. The active power filter controller can include a phase locked loop device or a notch filter for receiving a grid voltage and providing a corresponding voltage angle; first and second discrete fourier transform devices for using the voltage angle and the capacitor and load currents for extracting the fundamentals of the capacitor and load currents, respectively, and providing respective first and second output currents; and a subtractor for subtracting the first output current from the second output current to obtain the reference current. The active power filter can further include, situated between the first discrete fourier transform device and the subtractor, a multiplier for multiplying the first output current by a predetermined factor and a high pass filter for filtering the first output current. The filter circuit can include a circuit breaker coupling the inductor, the capacitor, and the first current sensor to the load for providing overcurrent protection to the filter circuit.

Active damping control for active power filter

A filter for a pulse width modulating inverter comprises a first inductor coupled to a phase connection of the pulse width modulating inverter, a second inductor coupled between the first inductor at a first-second coupling junction and a load, and a series configuration comprising a resistor and a capacitor coupled in series. The series configuration has one end coupled to the first-second coupling junction. If desired, the first inductor can be coupled between a phase connection of the pulse width modulating inverter and directly to the load, and the series configuration can have one end coupled to the load. The series configuration can further include a third inductor. Furthermore, the series configuration can be replaced by a parallel configuration comprising a resistor and a capacitor coupled in parallel, and the parallel configuration can further include a third inductor coupled in series to the resistor and the capacitor coupled in parallel. A second end of the series configuration can be coupled to a neutral or, if the filter includes a fourth inductor coupled to a second phase connection and a fifth inductor coupled between the fourth inductor at a fourth-fifth coupling junction and the load, the second end can be coupled to the fourth-fifth coupling junction. The filter can be used in single phase or multi-phase applications.

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Niskayuna, NY, United States of America

Albert Andreas Esser