Name: balanced delta-delta power circuit
Uploaded: 2024-07-08T13:19:57.000Z
Duration: 1 min 17 s
Channel: JoVE

Un sistema equilibrado de delta a triángulo tiene una fuente y una carga conectadas en triángulo.
Se supone que las fuentes conectadas en triángulo están en secuencia positiva para expresar los voltajes de fase, que son idénticos a los voltajes de línea.
Suponiendo impedancias de línea cero, los voltajes de fase coinciden con el voltaje a través de las impedancias.
Las corrientes de fase son iguales a la relación entre el voltaje de fase y la impedancia de carga por fase.
Las corrientes de línea se derivan de las corrientes de fase utilizando la ley de corriente de Kirchhoff en los nodos de las cargas conectadas en delta.
Cada corriente de línea se retrasa 30 grados con respecto a su corriente de fase correspondiente, siendo su magnitud la raíz cuadrada de tres veces la corriente de fase.
Alternativamente, el circuito de delta a delta se puede analizar convirtiendo la fuente y la carga a sus equivalentes Y.
Para la fuente conectada en Y, el voltaje de fase correspondiente es igual a cada voltaje de línea de la fuente conectada en delta dividido por una raíz cuadrada de tres, y su fase se desplaza en menos 30 grados.
La impedancia de carga conectada Y es igual a la impedancia de carga conectada delta dividida por tres.
Ahora, el circuito monofásico equivalente se puede usar para determinar las tres corrientes de línea.

el circuito Δ a Δ

The Delta-to-Delta Circuit

En una configuración triángulo-triángulo, la fuente y la carga están conectadas en forma triangular, formando un circuito cerrado que divide la red en tres fases distintas. Esta configuración hace que los voltajes de fase sean idénticos a los voltajes de línea. Suponiendo que las fuentes estén en secuencia positiva, los voltajes de fase se pueden expresar directamente sin tener un cable neutro.
<img alt="Equation 1" src="/files/ftp_upload/15131/15131_Equation_1.svg" style="height: 13px;">
Las corrientes de fase en una carga conectada en triángulo se calculan dividiendo el voltaje de fase por la impedancia de carga por fase:
<img alt="Equation 2" src="/files/ftp_upload/15131/15131_Equation_2.svg" style="height: 32px;">
En esta configuración, la Ley de Corrientes de Kirchhoff (KCL) da cada corriente de línea como la suma vectorial de las corrientes de las dos fases restantes, lo que lleva al principio general de que cada corriente de línea es la raíz cuadrada de tres veces la magnitud de la corriente de fase. Tiene un retraso de 30 grados con respecto a la corriente de fase debido a las diferencias de fase creadas por la conexión en triángulo.
Los análisis de tales sistemas implican convertir la fuente y la carga en sus equivalentes en estrella. Esta conversión simplifica el sistema trifásico en un circuito equivalente monofásico. La conversión implica ajustar tanto la magnitud como la fase de los voltajes de línea de la fuente conectada en triángulo:
<img alt="Equation 3" src="/files/ftp_upload/15131/15131_Equation_3.svg" style="height: 32px;">
<img alt="Equation 4" src="/files/ftp_upload/15131/15131_Equation_4.svg" style="height: 16px;">
Además, la impedancia de cada carga conectada en estrella es un tercio de la impedancia de la carga conectada en triángulo.
Las configuraciones equilibradas triángulo a triángulo se utilizan en aplicaciones industriales para maquinaria de alta potencia, transformadores y centros de control de motores. Permiten una transmisión de energía eficiente a largas distancias, reducen la distorsión armónica y facilitan el buen funcionamiento de los motores trifásicos al mantener niveles de voltaje constantes sin necesidad de una conexión neutra.

El circuito Δ a Δ

Un sistema equilibrado de delta a triángulo tiene una fuente y una carga conectadas en triángulo.
Se supone que las fuentes conectadas en delta están en secuencia positiva para expresar el ...

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balanced delta-delta power circuit

A balanced delta-delta power circuit uses a delta-connected source and a delta-connected load. The two deltas form a closed loop that creates three separate phases. In this setup, the phase voltages are the same as the line voltages. If the source is in positive sequence, the phase voltages can be written directly, and no neutral wire is needed.

The delta-connected load current is found by dividing the phase voltage by the impedance of each phase. For line current, Kirchhoff’s Current Law (KCL) applies at each node. The line current is the vector sum of the currents from the other two phases. In a balanced delta connection, each line current has a magnitude of square root of three times the phase current. It also lags the phase current by 30 degrees because of the phase shift in the delta network.

To analyze the system more simply, the source and load can be changed into wye-equivalents. A wye connection is a star-shaped circuit that makes three-phase analysis easier. This conversion turns the three-phase network into a single-phase equivalent circuit. The delta-connected source voltages must be adjusted in both magnitude and phase during the conversion. The impedance of each wye-connected load is one-third of the delta-connected load impedance.

Balanced delta-delta systems are common in industrial settings. They are used for high-power machines, transformers, and motor control centers. They also support long-distance power transmission and can help reduce harmonic distortion. In three-phase motors, the steady voltage levels help smooth operation without the need for a neutral connection.

Balanced Delta-Delta Power Circuit

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A balanced wye source and delta load form a common three-phase circuit with no neutral line connection. The source is Y-connected, and the load is delta-connected. To analyze the circuit, the first step is to assume a positive phase sequence. These phase voltages are then used to find the line voltages that appear across the delta load impedances. In the wye source, the phase voltages are V an, V bn, and V cn. In the delta load, the line voltages are V ab, V bc, and V ca. These line voltages...

the delta-to-delta circuit

A balanced delta-delta power circuit uses a delta-connected source and a delta-connected load. The two deltas form a closed loop that creates three separate phases. In this setup, the phase voltages are the same as the line voltages. If the source is in positive sequence, the phase voltages can be written directly, and no neutral wire is needed. The delta-connected load current is found by dividing the phase voltage by the impedance of each phase. For line current, Kirchhoff’s Current Law...

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.

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key terms and concepts

Explore how balanced delta-delta power circuits work, including line and phase voltages, line current, wye-equivalent conversion, and industrial uses.

Balanced Delta-Delta Power Circuit | 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.

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Balanced Delta-Delta Power Circuit

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