Name: delta-wye source and load connections
Uploaded: 2024-07-08T13:19:57.000Z
Duration: 1 min 16 s
Channel: JoVE

Um sistema delta para Y balanceado apresenta uma fonte conectada ao delta balanceada alimentando uma carga conectada ao Y balanceada.
Neste circuito delta-Y, uma sequência abc positiva é assumida para expressar as tensões de fase, que também servem como tensões de linha da fonte conectada ao delta.
A lei de tensão de Kirchhoff pode ser aplicada a um loop no circuito para derivar uma relação entre duas das correntes de linha.
Como uma sequência positiva é assumida, essas correntes de linha têm uma diferença de fase de 120 graus, que é usada para determinar uma delas.
As outras duas correntes de linha são obtidas usando a sequência de fase positiva.
As correntes de fase do circuito delta-Y são aproximadamente iguais às correntes de linha.
Como alternativa, a fonte conectada ao delta pode ser substituída por sua fonte conectada ao Y equivalente.
O circuito Y-Y obtido é analisado considerando um circuito monofásico equivalente e determinando as correntes de três linhas.
Este circuito também pode ser transformado em um sistema delta-delta para fins de análise, pois a carga conectada ao delta é frequentemente preferida devido à facilidade de alterar cargas individuais.

o circuito delta-to-y

No circuito delta-estrela, a fonte está conectada em delta, enquanto a carga está na configuração estrela. Isso significa que a tensão de fase da fonte conectada em delta é igual à tensão de linha da carga conectada em estrela. A conexão entre as correntes de duas linhas origina-se da fonte conectada em delta. A diferença de fase no sistema balanceado permite calcular uma corrente de linha em função da outra, utilizando a sequência positiva de fases. No sistema delta-estrela, as correntes de fase na carga conectada em estrela são diretamente iguais às correntes de linha da fonte delta, devido à configuração estrela da carga que simplifica o fluxo da fonte delta. A relação entre as correntes de linha e de fase em uma configuração estrela mostra que a corrente de fase na carga conectada em estrela é igual à corrente de linha da fonte conectada em delta.
Outra maneira de obter as correntes de linha é substituir a fonte conectada em delta pela sua fonte equivalente conectada em estrela. As tensões linha a linha de uma fonte conectada em estrela estão adiantadas em 30 graus em relação às tensões de fase correspondentes. Isso significa que cada tensão de fase da fonte equivalente conectada em estrela é obtida dividindo a tensão de linha correspondente da fonte conectada em delta pela raiz quadrada de três e mudando sua fase em -30 graus. Como resultado, a fonte equivalente conectada em estrela tem tensões de fase deslocadas em 120 graus de acordo.
Ao converter uma configuração delta em estrela, o sistema pode obter uma melhor regulação de tensão e permitir o uso de um fio neutro. Este fio neutro permite o aterramento do sistema, aumentando a segurança e a estabilidade.
A configuração delta-a-delta balanceada é usada para transmitir eletricidade por longas distâncias, onde os níveis de alta tensão precisam ser reduzidos para níveis utilizáveis ​​para uso industrial, comercial e residencial.

O Circuito Delta-To-Y

Um sistema delta para Y balanceado apresenta uma fonte conectada ao delta balanceada alimentando uma carga conectada ao Y balanceada.
Neste circuito delta-Y, um abc positivo ...

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The Delta-to-Y Circuit

delta-wye source and load connections

A balanced delta-wye circuit connects a delta-connected source to a wye-connected load. In this setup, the phase voltage of the delta source equals the line voltage of the wye load. The source also sets the line currents that flow into the load.

For a balanced system, the phase difference between currents makes it possible to find one line current from the other by using the positive sequence of phases. In the wye-connected load, each phase current equals the line current from the delta source. That relationship makes current analysis simpler in the load section.

The line currents can also be found by replacing the delta source with an equivalent wye source. In that conversion, each phase voltage is the matching line voltage divided by the square root of three and shifted by -30 degrees. The line-to-line voltages of a wye source lead the phase voltages by 30 degrees, so the equivalent wye source keeps the phases spaced 120 degrees apart.

Changing a delta connection to a star, or wye, connection can improve voltage regulation. It also allows the use of a neutral wire. That neutral wire supports grounding, which improves safety and stability. Balanced delta systems are also used for long-distance power transmission, where high voltage must later be stepped down for industrial, commercial, and residential use.

Delta-Wye Source and Load Connections

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Wye Source and Delta Load Currents

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the delta-to-y circuit

A balanced delta-wye circuit connects a delta-connected source to a wye-connected load. In this setup, the phase voltage of the delta source equals the line voltage of the wye load. The source also sets the line currents that flow into the load. For a balanced system, the phase difference between currents makes it possible to find one line current from the other by using the positive sequence of phases. In the wye-connected load, each phase current equals the line current from the delta source.

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key terms and concepts

Learn how a balanced delta source powers a wye load, how line and phase currents relate, and how a delta source can be converted to an equivalent wye source.

Delta-Wye Source and Load Connections | JoVE K12

JoVE Core Electrical Engineering offers easy-to-understand animated videos that cover fundamental concepts of electric circuits along with circuit analysis techniques. It incorporates first-order and second-order circuits using operational amplifiers and circuit transformation concepts. The inclusion of practical design examples and real-world applications through scientist-in-action videos adds significant educational value, making complex concepts accessible.

electrical engineering

Delta-Wye Source and Load Connections

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