Allen-bradley Company, LLC

Rockwell Automation Technologies Incorporated

Other

Eaton Corporation

National Research Development Corporation

Reliance Electric Technologies, LLC

University of Sussex Intellectual Property Limited

Peter J Unsworth

Frederick Michael Discenzo

James J Kinsella

Vetcha Sarat Babu

Li Chen

Timothy M Rowan

Kenneth Alan Loparo

John C Merrison

Dragica Kostic Perovic

Muslum Arkan

Sarat Babu Vetcha

Xin Zhou

Yuan Wang

Christopher John Wieloch

Lei Zhang

Michael Thomas Little

Jan Bezdicek

Carl J Dister

Bohumir Sladek

Dukki Chung

Fred M Discenzo

Charles T Younger

Ondrej Flek

Jinghan Tao

Joseph K Zevchek

Guy A Moore

Gerald W Davis

Jiri Ryba

Shiping Huang

Edward J Tomkin

Petr Tusla

Srdjan Perovic

Edward Hall Higham

Mongkol Pusayatanont

James J Kinsella Kinsella

Christopher J Wieloch Wieloch

A method and apparatus using electromagnetic switching in a two-step connection process is provided to minimize surge currents and torque oscillations in three-phase motors during starts.

Two-step connection of electric motors by means of electromagnetic switches

A method of starting and apparatus for starting a multiphase electrical machine is disclosed. The aim is to reduce oscillatory pulsation in torque generated by the motor and inrush current that occurs shortly after start-up. The starting method comprises the steps of first connecting at least one, but less than all, of a plurality of windings to a respective phase-shifted supply voltage at a controlled point in the supply phase. Then, after a controlled delay following the first connection, connecting the or each remaining winding of the machine a respective phase-shifted supply voltage. The invention has particular application to multiphase (most usually, 3-phase) motors. However, it can also be applied to other electrical machines, such as generators and transformers. The method can be performed at initial start-up or, in the case of application to a motor, at Y-delta switchover.

Motor starting and switching

In a method of monitoring two-phase fluid flow a vortex flowmeter is used to generate a signal indicative of the flow regime using the signal components and its fluctuations to determine the phase status of the fluid flow.

Monitoring of two-phased fluid flow

Systems and methods are disclosed for controlling and diagnosing the health of a motorized system. The systems may comprise a diagnostics system and a controller, wherein the diagnostics system employs a neural network, an expert system, and/or a data fusion component in order to assess the health of the motorized system according to one or more attributes associated therewith. The controller may operate the motorized system in accordance with a setpoint and/or a diagnostics signal from the diagnostics system. Also disclosed are methodologies for controlling and diagnosing the health of a motorized system, comprising operating a motor in the motorized system in a controlled fashion, and diagnosing the health of the motorized system according to a measured attribute associated with the motorized system, wherein the motor may be operated according to a setpoint and/or the diagnostics signal.

Motorized system integrated control and diagnostics using vibration, pressure, temperature, speed, and/or current analysis

A system and method is provided for monitoring the operating condition of a pump by evaluating fault data encoded in the instantaneous current of the motor driving the pump. The data is converted to a frequency spectrum which is analyzed to create a fault signature having fault attributes relating to various fault conditions associated with the pump. The fault signature is then input to a neural network that operates in conjunction with a preprocessing and post processing module to perform decisions and output those decisions to a user interface. A stand alone module is also provided that includes an adaptive preprocessing module, a one-shot unsupervised neural network and a fuzzy based expert system to provide a decision making module that operates with limited human supervision.

Detection of pump cavitation/blockage and seal failure via current signature analysis

Systems and methods are disclosed for controlling, diagnosing and prognosing the health of a motorized system. The systems may comprise a diagnostics system, a prognostic system and a controller, wherein the diagnostics system and/or prognostic system employs a neural network, an expert system, and/or a data fusion component in order to assess and/or prognose the health of the motorized system according to one or more attributes associated therewith. The controller may operate the motorized system in accordance with a setpoint and/or a diagnostics signal from the diagnostics system and/or prognostic information. Also disclosed are methodologies for controlling, diagnosing and prognosing the health of a motorized system, comprising operating a motor in the motorized system in a controlled fashion, diagnosing and/or prognosing the health of the motorized system according to a measured attribute associated with the motorized system, wherein the motor may be operated according to a setpoint and/or the diagnostics signal and/or prognosis.

Control of an induction motor is carried out to limit damaging arcing stress and mechanical stresses placed on the control contactor assembly and the induction motor resulting from the simultaneous or synchronous breaking and making of contactors employed to connect the windings of the motor to a power supply. Asynchronously connecting the windings to the power supply via the asynchronous or non-simultaneous closing of the contactors of a modular contactor assembly reduces the potentially damaging transient current, the associated torque oscillations, and mechanical stresses. The present invention is particularly applicable to delta motors that are started with its windings in a star or wye configuration followed by the reconnection of the windings in a delta configuration when the motor is at normal running speed.

Method and system of controlling asynchronous contactors for a multi-phase electric load

Systems and methodologies are disclosed for detecting faults and adverse conditions associated with electric motors. The method comprises obtaining a current signal associated with the motor, calculating a space vector from the current signal, determining a space vector angular fluctuation from the space vector, and analyzing the space vector angular fluctuation in order to detect at least one fault associated with the motor. Systems are disclosed having a diagnostics component adapted to obtain a space vector angular fluctuation from a current signal relating to operation of the motor, and to analyze the space vector angular fluctuation in order to detect at least one fault in the motor.

System and method for motor fault detection by space vector angular fluctuation

A method and apparatus for detecting a stator winding fault in an induction motor includes sampling instantaneous signals from the motor and then deriving sequence components of at least some of the instantaneous signals using a power decomposition technique (PDT), one of the sequence components being a total negative sequence current component. In addition, the method includes calculating an expected negative sequence current based on at least some of the sequence components. Thereafter, the method subtracts the expected negative sequence current from the total negative sequence current to determine a fault negative sequence current, wherein the fault negative sequence current is indicative of the fault. More preferably, the method additionally includes calculating an intrinsic motor negative sequence current based on at least some of the sequence components, and subtracting the intrinsic motor negative sequence current from the fault negative sequence current generated as described above to determine a modified fault negative sequence current. Notably, the method and apparatus are capable of detecting faults that cause a modified fault negative sequence current as low as approximately 0.2% of the full load current.

Method and apparatus for motor fault diagnosis

A method for controlling the starting, stopping and operation of an AC motor is provided. Each winding of the AC motor is interconnected to an AC source by a thyristor switch and a bypass contactor for providing voltage and current to the AC motor. The method includes a steps of sequently firing a pair of tyristor switches to bring the AC motor to full operating speed. Once at operating speed, the bypass contactors are closed. Upon detection of a voltage drop across a thyristor switch, the thyristor switch is fired immediately to transfer motor current from the bypass contactor to the thyristor switch in order to maintain voltage and current to the AC motor.

Method of controlling the starting, stopping and speed of an AC

A method and apparatus to be used with a motor controller for determining RMS line current during a start-up period or a stalled period using electrical values known to the controller. Various equations relate RMS line current to monitored thyristor and source voltages as well as the duration of non-conducting periods in line voltages to determine the RMS line current.

Method and apparatus for RMS current measurement in induction motors

A method and apparatus to be used with an inverter based motor controller for determining current phase angles for the current on a single phase of a three phase AC motor from an inverter generated high frequency phase voltage sequence. The invention detects turn on delay periods and compares phase voltages during consecutive turn on delay periods to determine phase current zero crossing times which can be used along with phase voltage zero crossing times to derive current phase angle information.

Method and apparatus for detecting current delay angle from motor

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East Sussex, United Kingdom

Peter J Unsworth