Name: voltage regulation in generators and wind turbines
Uploaded: 2024-11-21T14:54:38.000Z
Duration: 1 min 21 s
Channel: JoVE

Em geradores síncronos, o excitador fornece energia CC para o enrolamento de campo do rotor.
Os modelos mais antigos usam um gerador DC acionado por rotor como excitador, enquanto os modernos usam excitadores estáticos ou sem escovas.
Os excitadores estáticos retificam a energia CA dos terminais do gerador ou do barramento e a fornecem ao rotor.
Os excitadores sem escova usam um gerador síncrono invertido, retificando a energia CA dos enrolamentos da armadura para o enrolamento de campo.
Os excitadores tipo 1 têm um gerador CC acionado por eixo e um regulador de tensão que ajusta a corrente de campo com base na tensão terminal.
Em turbinas eólicas, o controle de tensão varia de acordo com o tipo de excitador. O Tipo 1 não possui controle direto, enquanto o Tipo 2 usa controle de resistência para manter a potência constante durante as rajadas de vento.
Os excitadores tipo 3 controlam a potência reativa, mantendo-a constante ou variando com a potência real.
Os diagramas de blocos visualizam o controle de tensão do gerador em programas de estabilidade transitória.
Os excitadores de alto ganho e resposta rápida aumentam a tensão de campo durante curtos-circuitos, melhorando a estabilidade transitória.
As equações do diagrama de blocos calculam a resposta transitória.

estabilidade transitória e controles do sistema

Generator Voltage Control

O controle da tensão do gerador é crucial para manter a operação estável de geradores síncronos e turbinas eólicas. Em modelos mais antigos, um gerador CC acionado pelo rotor fornece energia CC ao enrolamento de campo do rotor, e a energia é transferida por meio de anéis coletores e escovas. Nos modelos mais recentes, são usados ​​excitadores estáticos ou sem escovas. Os excitadores estáticos retificam a energia CA dos terminais do gerador e, em seguida, transferem a energia CC diretamente para o rotor. Os excitadores sem escovas, por outro lado, usam um gerador síncrono invertido no qual a energia CA é obtida de enrolamentos de armadura e retificada por meio de diodos montados no rotor, eliminando a necessidade de anéis coletores e escovas.


 O diagrama de blocos fornece um método padronizado para visualizar sistemas de controle de tensão do gerador. O excitador IEEE Tipo 1 usa um gerador CC acionado por eixo para criar a corrente de campo, com um regulador de tensão que ajusta a corrente de campo com base nas medições de tensão do terminal.

<img alt="Figure1" src="/files/ftp_upload/16172/16172_PT_figure_001.svg" style="height: 150px;">

 No diagrama de blocos, a tensão terminal, V_t é medida e comparada com uma tensão de referência V_ref. A diferença entre essas duas é usada para ajustar a tensão de campo. O regulador de tensão processa o erro de tensão com um ganho (K_a) e constante de tempo (T_a). A saída do regulador de tensão é a tensão de campo aplicada ao enrolamento de campo do gerador, que ajusta a tensão terminal. Esses modelos representam a dinâmica do excitador e do gerador, fornecendo um método claro para analisar e melhorar a estabilidade.


 As turbinas eólicas do tipo 1 empregam máquinas de indução de gaiola de esquilo sem regulação direta de tensão. Os sistemas do tipo 2 utilizam máquinas por indução de rotor enrolado com resistência externa ajustável, modeladas como um excitador, para manter uma saída de energia consistente, apesar das variações de velocidade do vento. As configurações do tipo 3 e do tipo 4 gerenciam a energia real e reativa. O controle de tensão do gerador envolve metodologias para garantir a operação estável e confiável de geradores síncronos e turbinas eólicas modernas.

Estabilidade transitória e controles do sistema

Em geradores síncronos, o excitador fornece energia CC para o enrolamento de campo do rotor.
Os modelos mais antigos usam um gerador DC acionado por rotor como excitador, ...

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Electrical Engineering

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Transient Stability and System Controls

Estabilidade Transitória e Controles do Sistema

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voltage regulation in generators and wind turbines

Generator voltage regulation helps keep synchronous generators and wind turbines working stably. Older systems use a DC generator driven by the rotor to supply DC power to the rotor field winding. That power is passed through slip rings and brushes.

Newer systems use static exciters or brushless exciters. A static exciter rectifies AC power from the generator terminals and sends DC power directly to the rotor. A brushless exciter uses an inverted synchronous generator, takes AC power from armature windings, and rectifies it with diodes mounted on the rotor. This design removes the need for slip rings and brushes.

A block diagram is often used to show how generator voltage control works in a standard way. The IEEE Type 1 exciter uses a shaft-driven DC generator to produce field current. A voltage regulator then adjusts that current based on the measured terminal voltage. In the diagram, terminal voltage, Vt, is compared with a reference voltage, Vref, and the difference is used to adjust field voltage.

The voltage regulator processes the voltage error with a gain, Ka, and a time constant, Ta. Its output is the field voltage applied to the generator field winding, which changes the terminal voltage. These models describe exciter and generator dynamics and help engineers analyze and improve stability.

Wind turbines use related control ideas in different machine types. Type 1 turbines use squirrel cage induction machines and do not have direct voltage regulation. Type 2 systems use wound rotor induction machines with adjustable external resistance, modeled as an exciter, to help keep power output steady when wind speed changes. Type 3 and Type 4 configurations manage both real and reactive power.

Voltage Regulation in Generators and Wind Turbines

voltage-regulation-in-generators-and-wind-turbines

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Wind Turbine Types and Generator Control

Wind turbine machine models are used to study how wind turbines behave in transient stability analysis. In this setting, induction machines and synchronous machines are the main model types. Induction machines are common because they are simple and reliable. Induction machines work through the rotating magnetic field made by the stator and rotor. A key term is slip, which is the difference between synchronous speed and rotor speed relative to synchronous speed. Slip is zero at synchronous...

generator voltage control

Generator voltage regulation helps keep synchronous generators and wind turbines working stably. Older systems use a DC generator driven by the rotor to supply DC power to the rotor field winding. That power is passed through slip rings and brushes. Newer systems use static exciters or brushless exciters. A static exciter rectifies AC power from the generator terminals and sends DC power directly to the rotor. A brushless exciter uses an inverted synchronous generator, takes AC power from...

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How Turbine Governors Stabilize Power Output

Turbine-governor control helps keep generator frequency and rotor speed stable when electrical load changes. It does this by matching turbine mechanical power with the power demand on the system. In a power grid, that balance is important for steady operation. Turbine-generator units also store kinetic energy because their parts are rotating. When load increases, that stored energy is released to help meet the demand. At first, electrical torque rises while mechanical torque stays nearly...

load-frequency control

Load-frequency control in power grids

Load-frequency control keeps a power grid stable when electrical demand changes. It helps keep system frequency and power flow within acceptable limits. Turbine-governor control reduces rotor speed changes after a load shift, but a steady-state frequency error can still remain when the turbine-governor reference setting does not change. In an interconnected power system, each area agrees to export or import a scheduled amount of power through tie-lines, which are the transmission lines that...

key terms and concepts

Learn how generator voltage regulation works with static, brushless, and IEEE Type 1 exciters, plus how wind turbine types manage stable power output.

Voltage Regulation in Generators and Wind Turbines | 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

Voltage Regulation in Generators and Wind Turbines

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