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Title: Precision electronic speed controller for an alternating-current

Abstract

A high precision controller for an alternating-current multi-phase electrical motor that is subject to a large inertial load. The controller was developed for and is particularly suitable for controlling, in a neutron chopper system, a heavy spinning rotor that must be rotated in phase-locked synchronism with a reference pulse train that is representative of an ac power supply signal having a meandering line frequency. The controller includes a shaft revolution sensor which provides a feedback pulse train representative of the actual speed of the motor. An internal digital timing signal generator provides a reference signal which is compared with the feedback signal in a computing unit to provide a motor control signal. In the preferred embodiment, the motor control signal is a weighted linear sum of a speed error voltage, a phase error voltage, and a drift error voltage, each of which is computed anew with each revolution of the motor shaft. The stator windings of the motor are driven by two amplifiers which are provided with input signals having the proper quadrature relationship by an exciter unit consisting of a voltage controlled oscillator, a binary counter, a pair of readonly memories, and a pair of digital-to-analog converters.

Inventors:
 [1]
  1. (Albuquerque, NM)
Issue Date:
Research Org.:
Los Alamos National Laboratory (LANL), Los Alamos, NM
OSTI Identifier:
866532
Patent Number(s):
4731572
Assignee:
United States of America as represented by Department of Energy (Washington, DC) LANL
DOE Contract Number:  
W-7405-ENG-36
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
precision; electronic; speed; controller; alternating-current; multi-phase; electrical; motor; subject; inertial; load; developed; particularly; suitable; controlling; neutron; chopper; heavy; spinning; rotor; rotated; phase-locked; synchronism; reference; pulse; train; representative; power; supply; signal; meandering; line; frequency; shaft; revolution; sensor; provides; feedback; internal; digital; timing; generator; compared; computing; unit; provide; control; preferred; embodiment; weighted; linear; error; voltage; phase; drift; computed; anew; stator; windings; driven; amplifiers; provided; input; signals; proper; quadrature; relationship; exciter; consisting; controlled; oscillator; binary; counter; pair; readonly; memories; digital-to-analog; converters; speed control; stator windings; feedback signal; phase error; reference pulse; pulse train; stator winding; reference signal; particularly suitable; control signal; input signals; timing signal; preferred embodiment; power supply; input signal; signal generator; voltage controlled; motor control; spinning rotor; voltage control; digital-to-analog converter; generator provides; phase electric; unit consisting; speed controller; analog converter; precision control; electrical motor; controlled oscillator; /318/

Citation Formats

Bolie, Victor W. Precision electronic speed controller for an alternating-current. United States: N. p., 1988. Web.
Bolie, Victor W. Precision electronic speed controller for an alternating-current. United States.
Bolie, Victor W. Fri . "Precision electronic speed controller for an alternating-current". United States. https://www.osti.gov/servlets/purl/866532.
@article{osti_866532,
title = {Precision electronic speed controller for an alternating-current},
author = {Bolie, Victor W.},
abstractNote = {A high precision controller for an alternating-current multi-phase electrical motor that is subject to a large inertial load. The controller was developed for and is particularly suitable for controlling, in a neutron chopper system, a heavy spinning rotor that must be rotated in phase-locked synchronism with a reference pulse train that is representative of an ac power supply signal having a meandering line frequency. The controller includes a shaft revolution sensor which provides a feedback pulse train representative of the actual speed of the motor. An internal digital timing signal generator provides a reference signal which is compared with the feedback signal in a computing unit to provide a motor control signal. In the preferred embodiment, the motor control signal is a weighted linear sum of a speed error voltage, a phase error voltage, and a drift error voltage, each of which is computed anew with each revolution of the motor shaft. The stator windings of the motor are driven by two amplifiers which are provided with input signals having the proper quadrature relationship by an exciter unit consisting of a voltage controlled oscillator, a binary counter, a pair of readonly memories, and a pair of digital-to-analog converters.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1988},
month = {1}
}

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