What is Electrical Reactor?

Encyclopedia
09/07/2024


What is Electrical Reactor?


Electrical Reactor Definition: An electrical reactor, also known as a line reactor or choke, is a coil that creates a magnetic field to limit current rise, reducing harmonics and protecting electrical drives from power surges.


Types of Electrical or Line Reactors


A reactor has many roles to play in an electrical power system. The reactors are normally classified according to their modes of application. Such as:

 


  • Shunt Reactor

  • Current Limiting and Neutral Earthing Reactor

  • Damping Reactor

  • Tuning Reactor

  • Earthing Transformer

  • Arc Suppression Reactor

  • Smoothing Reactor 


From a constructional point of view, the reactors are classified as:


  • Air Core Reactor

  • Gapped Iron Core Reactor


From an operational point of view, the reactors are classified as:

 


  • Variable Reactor

  • Fixed Reactor


In addition to this, the reactor can also be classified as:

 


  • Indoor Type 

  • Outdoor Type Reactor



0ef5591f3ba89d3f9480c06c0b85c2d1.jpeg



Shunt Reactor


A shunt reactor is connected in parallel within the system. Its main purpose is to compensate for the capacitive current component, meaning it absorbs reactive power (VAR) generated by the system’s capacitive effect.


In a substation, shunt reactors are connected normally between line and ground. The VAR absorbed by the reactor can be fixed or variable depending on the system requirement. The variation of VAR in the reactor can be achieved by using phase control thyristors or by DC magnetizing of the iron core. This variation can also be achieved by offline or online tap changer associated with the reactor.


A shunt reactor can be single-phase or three-phase, based on the power system’s configuration. It can have an air core or a gapped iron core. Some shunt reactors include magnetic shielding and additional windings to supply auxiliary power.


Series Reactor


A current limiting reactor is a type of series reactor connected in series within the system. It limits fault currents and helps in load sharing in parallel networks. When connected to an alternator, it’s called a generator line reactor, which reduces stress during three-phase short circuit faults.


The series reactor may also be connected in series in the feeder or electrical bus to minimize the effect of short circuit fault at other parts of the system. As an effect of short circuit current in that portion of the system becomes limited, the short circuit current withstand rating of the equipment and conductors of that portion of the system can be smaller. This makes the system cost-effective.


When a reactor of suitable rating is connected between neutral and earth connection of a system, to limit the line to earth current during earth fault in the system, it is called Neutral Earthing Reactor.


When a capacitor bank is a switch on in uncharged condition there may be a high inrush current flowing through it. To limit this inrush current reactor is connected in series with each phase of the capacitor bank. The reactor used for this purpose is known as damping reactor. This damps the transient condition of the capacitor. It also helps to suppress the harmonics present in the system. These reactors are typically rated with their highest inrush current in addition to its continuous current carrying capacity.


The wave trap connected in series with the feeder line is a kind of reactor. This reactor along with the Coupling Capacitor of the line creates a filter circuit to block the frequencies other than power frequency. This type of reactor is mainly used to facilitate Power Line Carrier Communication. This is called Tuning Reactor. As it is used to create a filter circuit, it is also called a filter reactor. Commonly and popularly it is known as Wave Trap.


In a delta connected power system, a star point or neutral point is created by using zigzag star connected 3 phase reactor, called an earthing transformer. This reactor may have secondary winding to obtain power for auxiliary supply to the substation. That is why this reactor is also referred to as an earthing transformer.


The reactor connected between neutral and earth to limit single phase to earth fault current is called Arc Suppression Reactor.


A reactor is also used to filter out harmonics present in DC power. A reactor used in DC power network for this purpose is called smoothing reactor.

 

Encyclopedia

The Electricity Encyclopedia is dedicated to accelerating the dissemination and application of electricity knowledge and adding impetus to the development and innovation of the electricity industry.

What is Automatic Voltage Regulator?
What is Automatic Voltage Regulator?
An automatic voltage regulator is employed to regulate voltage, converting fluctuating voltages into a constant one. Voltage fluctuations mainly stem from variations in the load on the supply system. Such voltage variations can damage the equipment within the power system. These fluctuations can be mitigated by installing voltage - control equipment at various locations, such as near transformers, generators, and feeders. Multiple voltage regulators are often placed throughout the power system t
Edwiin
05/22/2025
What is Static Voltage Regulator?
What is Static Voltage Regulator?
Types of Static Voltage RegulatorThe static voltage regulator is superior to electromechanical regulators in respect of the accuracy of control, response, reliability and maintenance. The static voltage regulator is mainly classified into two types. They are;Servo Type Voltage RegulatorMagnetic Amplifier RegulatorThe types of static voltage regulator are described below in details;Servo Type Voltage RegulatorThe main feature of the servo type voltage regulator is the use of the amplidyne. The am
Edwiin
05/21/2025
What is Arc Extinction Circuit Breaker?
What is Arc Extinction Circuit Breaker?
When the current-carrying contacts of a circuit breaker separate, an arc forms and persists briefly after contact separation. This arc is hazardous due to the heat energy it generates, which can produce explosive forces.A circuit breaker must extinguish the arc without damaging equipment or endangering personnel. The arc significantly influences the breaker’s performance. Interrupting aDC arcis inherently more challenging than anAC arc. In an AC arc, the current naturally reaches zero duri
Edwiin
05/20/2025
Air Break Circuit Breaker
Air Break Circuit Breaker
In an air break circuit breaker, the arc is initiated and extinguished in substantially static air as the arc moves. These breakers are used for low voltages, generally up to 15 kV, with rupturing capacities of 500 MVA. As an arc-quenching medium, air circuit breakers offer several advantages over oil, including:Elimination of risks and maintenance associated with oil use.Absence of mechanical stress caused by gas pressure and oil movement.Elimination of costs from regular oil replacement due to
Edwiin
05/20/2025
Inquiry
Download
IEE-Business is dedicated to serving the personnel in the global power industry.
Join IEE-Business, not only can you discover power equipment and power knowledge, but also canhnd like - minded friends!