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Title: Variable speed wind turbine generator with zero-sequence filter

Abstract

A variable speed wind turbine generator system to convert mechanical power into electrical power or energy and to recover the electrical power or energy in the form of three phase alternating current and return the power or energy to a utility or other load with single phase sinusoidal waveform at sixty (60) hertz and unity power factor includes an excitation controller for generating three phase commanded current, a generator, and a zero sequence filter. Each commanded current signal includes two components: a positive sequence variable frequency current signal to provide the balanced three phase excitation currents required in the stator windings of the generator to generate the rotating magnetic field needed to recover an optimum level of real power from the generator; and a zero frequency sixty (60) hertz current signal to allow the real power generated by the generator to be supplied to the utility. The positive sequence current signals are balanced three phase signals and are prevented from entering the utility by the zero sequence filter. The zero sequence current signals have zero phase displacement from each other and are prevented from entering the generator by the star connected stator windings. The zero sequence filter allows the zeromore » sequence current signals to pass through to deliver power to the utility.

Inventors:
 [1]
  1. Golden, CO
Issue Date:
Research Org.:
National Renewable Energy Laboratory (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
871802
Patent Number(s):
5798632
Assignee:
Midwest Research Institute (Kansas City, MO)
DOE Contract Number:  
AC36-83CH10093
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
variable; speed; wind; turbine; generator; zero-sequence; filter; convert; mechanical; power; electrical; energy; recover; form; phase; alternating; current; return; utility; load; single; sinusoidal; waveform; sixty; 60; hertz; unity; factor; excitation; controller; generating; commanded; zero; sequence; signal; components; positive; frequency; provide; balanced; currents; required; stator; windings; generate; rotating; magnetic; field; optimum; level; allow; generated; supplied; signals; prevented; entering; displacement; star; connected; allows; pass; deliver; rotating magnetic; power generated; stator windings; current signals; stator winding; wind turbine; variable frequency; electrical power; magnetic field; alternating current; single phase; current signal; mechanical power; turbine generator; variable speed; zero frequency; speed wind; phase displacement; phase alternating; power factor; optimum level; frequency current; /322/290/

Citation Formats

Muljadi, Eduard. Variable speed wind turbine generator with zero-sequence filter. United States: N. p., 1998. Web.
Muljadi, Eduard. Variable speed wind turbine generator with zero-sequence filter. United States.
Muljadi, Eduard. Thu . "Variable speed wind turbine generator with zero-sequence filter". United States. https://www.osti.gov/servlets/purl/871802.
@article{osti_871802,
title = {Variable speed wind turbine generator with zero-sequence filter},
author = {Muljadi, Eduard},
abstractNote = {A variable speed wind turbine generator system to convert mechanical power into electrical power or energy and to recover the electrical power or energy in the form of three phase alternating current and return the power or energy to a utility or other load with single phase sinusoidal waveform at sixty (60) hertz and unity power factor includes an excitation controller for generating three phase commanded current, a generator, and a zero sequence filter. Each commanded current signal includes two components: a positive sequence variable frequency current signal to provide the balanced three phase excitation currents required in the stator windings of the generator to generate the rotating magnetic field needed to recover an optimum level of real power from the generator; and a zero frequency sixty (60) hertz current signal to allow the real power generated by the generator to be supplied to the utility. The positive sequence current signals are balanced three phase signals and are prevented from entering the utility by the zero sequence filter. The zero sequence current signals have zero phase displacement from each other and are prevented from entering the generator by the star connected stator windings. The zero sequence filter allows the zero sequence current signals to pass through to deliver power to the utility.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Jan 01 00:00:00 EST 1998},
month = {Thu Jan 01 00:00:00 EST 1998}
}