Name: voltage and reactive power control
Uploaded: 2024-11-21T14:54:26.000Z
Duration: 1 min 30 s
Channel: JoVE

Controlling power flow requires managing components like generators&#39; prime mover and excitation control, shunt capacitor banks, reactors, static var systems, and regulating transformers.
A generator under steady-state conditions is represented by the Th&#233;venin equivalent, including terminal voltage, excitation voltage, power angle, and synchronous reactance.
The generator&#39;s current, real, and reactive powers are then calculated.
Increasing the power angle boosts real power but decreases reactive power, while raising excitation voltage increases reactive power and slightly decreases the power angle.
Adding a shunt capacitor bank to a bus increases its voltage, whereas a shunt reactor decreases it.
Tap-changing and voltage-regulating transformers control bus voltages and reactive power flows. Phase-angle regulating transformers control bus angles and real power flows.
Alterations in tap settings or voltage regulation alters the transformer&#39;s turns ratio computed by the power flow program.
The program also evaluates the effects of switching lines, transformers, loads, and generators. It simulates changes to meet future load growth.

controle van de energiestroom

Er zijn verschillende methoden om de energiestroom in energiesystemen te regelen:

<ul style="list-style-type: disc; padding-left: 35px; margin: 0;">
 <li>Primaire aandrijving en excitatieregeling van generatoren</li>
 <li>Schakelen van shuntcondensatorbanken, shuntreactoren en statische V-systemen</li>
 <li>Regeling van tap- en regeltransformatoren</li>
</ul>

Een eenvoudige generator in het systeem wordt weergegeven door zijn Thevenin-equivalent circuit, dat zijn model vertegenwoordigt dat werkt onder gebalanceerde stationaire omstandigheden. De belangrijkste parameters omvatten de generatorterminalspanning V_t, de excitatiespanning E_g, de vermogenshoek δ en de positieve-sequentie synchrone reactantie X_g.

<img alt="Figure1" src="/files/ftp_upload/16150/16150_PT_Image_1.svg" style="height: 36px;">

De generatorstroom is:

<img alt="Equation1" src="/files/ftp_upload/16150/16150_PT_equation_1.svg" style="height: 160px;">

en het geleverde complexe vermogen is:

<img alt="Equation2" src="/files/ftp_upload/16150/16150_PT_equation_2.svg" style="height: 36px;">

Een shuntcondensatorbank die aan een voedingssysteembus wordt toegevoegd, verhoogt de grootte van de busspanning en compenseert reactief vermogen. Deze aanpassing wordt gemodelleerd door een condensator aan te sluiten, die negatief reactief vermogen absorbeert, waardoor de totale vraag naar reactief vermogen van het systeem wordt verminderd. Daarnaast worden taptransformatoren gebruikt om busspanningen te regelen en reactieve vermogensstromen te beheren door de wikkelverhouding aan te passen, waardoor het spannings- en reactieve vermogensprofiel in het netwerk wordt beïnvloed. Deze aanpassing helpt de stabiliteit en efficiëntie van het systeem te behouden, belastingvariaties op te vangen en de vermogensafgifte te verbeteren.

Vermogensstroomstudies gebruiken vaak trial and error om generatie-niveaus en regel-instellingen aan te passen. Deze aanpassingen zorgen ervoor dat het systeem voldoet aan de gewenste apparatuurbelastingen en spanningsprofielen, en bereiden het netwerk voor op belastinggroei, nieuwe transmissies, transformatoren en generatie. De controle van de vermogensstroom is een dynamisch proces waarbij verschillende methoden en aanpassingen betrokken zijn om de stabiliteit, efficiëntie en betrouwbaarheid van het systeem te behouden.

Controle van de energiestroom

Controlling power flow requires managing components like generators&#39; prime mover and excitation control, shunt capacitor banks, reactors, static var ...

Education

JoVE Core

Electrical Engineering

Elektrotechniek

Unit 1

Steady-State Transmission Lines and Power Flows

Stationaire transmissieleidingen en vermogensstromen

steady-state-transmission-lines-and-power-flows

KEY TERMS AND CONCEPTS

BELANGRIJKE TERMEN EN BEGRIPPEN

Control of Power Flow

voltage and reactive power control

Voltage and reactive power control help keep a power system stable and efficient. In this topic, generator settings, switched equipment, and transformer taps work together to guide how power moves through the network.

A generator can be modeled with a Thevenin equivalent circuit under balanced steady-state conditions. The main terms are terminal voltage Vt, excitation voltage Eg, power angle δ, and positive-sequence synchronous reactance Xg. From this model, the generator current and the complex power delivered can be determined.

One way to adjust power flow is through generator control. The prime mover and the excitation system can be changed to influence generation and voltage behavior. Power flow studies often use trial and error to set these values and other controls.

Shunt capacitor banks, shunt reactors, and static var systems are also used to manage reactive power. A shunt capacitor bank connected to a bus raises the bus voltage magnitude. It also compensates for reactive power by absorbing negative reactive power, which lowers the system’s overall reactive power demand.

Tap-changing and regulating transformers provide another way to control bus voltage and reactive power flow. By changing the turns ratio, these transformers alter the voltage profile across the network. This helps the system handle load changes and support efficient power delivery.

These control steps are used to meet equipment loading limits and desired voltage profiles. They also prepare the network for load growth, new transmission lines, transformers, and added generation. In this way, power flow control remains a dynamic process that supports stability, efficiency, and reliability.

Voltage and Reactive Power Control

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lossless lines

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Lossless transmission lines in electrical engineering are described by a purely imaginary propagation constant and a resistive characteristic impedance. Their ABCD parameters show an equivalent pi circuit with an imaginary series impedance and a shunt admittance. When the product of beta and line length is less than pi, the line has inductive series impedance and capacitive shunt admittance, which keeps it lossless. Wavelength is the physical length over which voltage or current phase changes...

maximum power flow and line loadability

Transmission Line Power Limits and Loadability

Transmission line power limits and loadability depend on voltage, angle, and line impedance. For lossy transmission lines, ABCD parameters in phasor form are used to relate sending-end and receiving-end voltages and currents. This matrix relation makes it possible to find the receiving-end current and then calculate the complex power delivered to the load. From the complex power, the real and reactive power components can be determined. For a lossless line, the equations become simpler, and...

the power flow problem and solution

Power Flow Analysis in Electric Networks

Power flow analysis helps determine how real and reactive power move through an electric network. It uses the system’s single-line diagram, which shows the buses, transmission lines, transformers, and loads. The analysis focuses on balanced three-phase steady-state operation. Each bus in the system has four key variables: voltage magnitude V k, phase angle δ k, real power P k, and reactive power Q k. Two of these four variables are treated as inputs. The power flow program solves for the...

control of power flow

Voltage and reactive power control help keep a power system stable and efficient. In this topic, generator settings, switched equipment, and transformer taps work together to guide how power moves through the network. A generator can be modeled with a Thevenin equivalent circuit under balanced steady-state conditions. The main terms are terminal voltage Vt, excitation voltage Eg, power angle δ, and positive-sequence synchronous reactance Xg. From this model, the generator current and the...

fast decoupled and dc powerflow

Power Flow Shortcuts for Grid Contingencies

Fast decoupled power flow and DC power flow give engineers faster ways to study a power system during contingencies such as generator outages or transmission line failures. These methods help operators get quick power flow solutions, which is important for real-time system adjustments. Fast decoupled power flow simplifies the Jacobian matrix, the set of equations used in power flow calculations, by neglecting some elements. The method drops J2 and J3 and assumes voltage magnitudes stay close...

key terms and concepts

Learn how generator settings, shunt capacitors, reactors, and tap-changing transformers help control voltage, reactive power, and power flow in power systems.

Voltage and Reactive Power Control | 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 and Reactive Power Control

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