Hamilton Sundstrand Corporation

Charles J Romenesko

Albert L Markunas

Vijay K Maddali

David G Halsey

Michael C Harke

Daniel M Saban

John F Defenbaugh

Jun Hu

William J Peterson

A controller continually updates rotor time constant estimation of an induction machine by interrogating the induction machine with a small signal oscillation and monitoring the response. The small signal oscillation is injected onto the d-axis current command signal, and is generated at a frequency that represents the most recent estimate of the rotor time constant (i.e., rotor time constant equal the inverse of the frequency). The controller monitors rotor flux generated in response to the small signal oscillation, and updates the most recent estimate of the rotor time constant based on the monitored rotor flux. This process is repeated continuously to allow for the continuous updating of the rotor time constant.

On-line measurement of an induction machine's rotor time constant by small signal d-axis current injection

A power turbine speed control system for a turbo-shaft type gas turbine engine that has a gas generator compressor spool and a power turbine spool and drives an electrical generator that powers at least one electrical load by way of at least one electrical bus, comprises a power turbine controller that senses the rotary speed of the power turbine spool and generates at least one signal that changes the torque of the electrical generator in response to the sensed change in the rotary speed of the power turbine spool.

Power turbine speed control using electrical load following

A controller estimates a motor position. The controller includes a driver and an injector. The driver generates a fundamental control signal. The injector generates a position carrier voltage that superimposed on the fundamental control signal. The injector alters the magnitude of the carrier voltage signal in response to the corresponding amplitude of the fundamental control signal. In a disclosed example, the injector increases the carrier voltage signal magnitude as the fundamental control current signal approaches a zero crossing. The injector then gradually decreases the carrier voltage signal magnitude as the fundamental control current signal magnitude increases from zero.

Signal control for motor position determination

A controller applies a pattern of pulses to switching elements within a multi-level controller to effectuate control of the fundamental voltage magnitude and phase associated with the converter, as well as providing harmonic minimization of the 5and 7level harmonics. The controller combines a first pattern of pulses with a second pattern of pulses phase shifted by an amount based on the desired fundamental voltage magnitude to create a third pattern of pulses. The controller applies a phase shift to the third pattern of pulses based on the desired fundamental voltage phase. The controller supplies switching control waveforms to active components within the multi-level controller based on the phase shifted third pattern of pulses such that the desired fundamental voltage magnitude and phase is generated and selected harmonics are minimized.

Voltage control and harmonic minimization of multi-level converter

A field oriented control system for a brushless wound field synchronous machine that determines positioning of a rotor for the machine from exciter stator electrical potentials and current harmonics.

Brushless wound field synchronous machine rotor position tracking with exciter stator current harmonic tracking

A shaft sensorless rotor angular position and velocity sensing system for a ynamoelectric machine that includes: a reference frame transformation function for transforming measured currents and potentials applied to a stator of the dynamoelectric machine to a two-phase &#x3b1;-&#x3b2; stationary frame to produce transformed currents I,Iand transformed potentials V,V; first and second multipliers to produce signals I*R,I*R; first and second summers to produce signals V,&#x2212;I*R,V&#x2212;I*R; first and second lag functions to produce signals third and fourth multipliers to produce signals I*L,I*L; third and fourth summers to produce signals that correspond to extended rotor flux values &#x3bb;,&#x3bb;; and a phase lock loop (PLL) to derive estimated rotor angular position and velocity values {circumflex over (&#x3b8;)}, {circumflex over (&#x3c9;)} for the dynamoelectric machine from the extended rotor flux values &#x3bb;,&#x3bb;.

Shaft sensorless angular position and velocity estimation for a dynamoelectric machine based on extended rotor flux

A carrier injection sensorless (CIS) starting control system that is capable of determining the angular position and velocity of a rotor for a wound field synchronous machine at or near rest and comprises north-south pole determination and a variable or dual frequency carrier signal for improved performance throughout the start sequence for the machine.

Carrier injection sensorless control of aircraft variable frequency wound field synchronous starter/generators

A system for enhancing the performance of a carrier insertion sensorless (CIS) position sensing system for a wound field synchronous machine that utilises the positively rotating components (+2&#x3c9;t) of the carrier second harmonic currents that contain rotor position information before field excitation to serve as a north-south pole indicator that determines if the CIS system has locked onto the north or south pole of the rotor.

Growing community of inventors

Roscoe, IL, United States of America

Charles J Romenesko