A line reactor is an electromagnetic device specifically designed to limit the rate of current rise. Reactors are generally divided into line reactors and load reactors. Line reactors are input reactors, and load reactors are output reactors.
When you are responsible for selecting and installing line reactors, you need to fully consider the pros and cons of installing this hardware, and you need some professional guidance. This article can provide you with some guidance on the selection and installation of line reactors.
1.What Is A Line Reactor?
2.What Is Impedance?
3.What Are The Benefits Of Line Reactor?
4.What Are The Types Of Line Reactors?
5.What Are The Applications Of Line Reactor?
6.How Line Reactor Works?
7.What Are The Line Reactor Impedance Ratings?
8.What Are The Considerations Before Selecting The Right Line Reactor?
9.What Are The Load Reactors?
10.What Are The Benefits Of Load Reactors?
What Is A Line Reactor-sourced: LTEC
A line reactor is also called a line inductor. It is an electromagnetic device consisting of a steel core wrapped with a copper coil. The coil creates a magnetic field that, when current flows through it, limits the rate of current rise, reduces harmonics, and protects electrical equipment.
Two types of line reactors are commonly used with frequency converters: AC reactors and DC reactors.
When the reactor is installed between the power system and the frequency converter, it is called an AC line reactor. When a DC reactor is inserted into the DC link of the drive, it is called a DC reactor.
Both AC and DC reactors act as harmonic current limiters. When an AC reactor is installed between the frequency converter and the power supply, it can limit the impact of power system surges and fluctuations on equipment, protect more equipment, prevent overvoltage tripping, improve the reliability and service life of the frequency converter, improve the overall power factor, and reduce false tripping.
What Is Impedance-sourced: electrical4u
Resistance refers to the combination of the voltage in the system and the line current flowing through the reactor. It is primarily measured in ohms and is usually expressed as a percentage. The impedance level for each line reactor rating is usually expressed as a percentage. The higher the current flowing through the reactor, the greater the percentage impedance imposed by the system. If a reactor has an impedance rating of 3% or 5%, this means that when current passes through the reactor, the reactor imposes an impedance of 3% or 5%.
Using line reactors can improve the power quality of the power system and protect electrical equipment at the same time. It is widely used in various inverters and motor control systems. Its main advantages are as follows:
Extend equipment life
Line reactors can protect the inverter from harmonics and harmful surges, while absorbing voltage spikes and surge currents. This prevents the inverter from being disturbed and extends the service life of the inverter.
Reduce harmonic distortion
Reduce harmonic distortion-sourced: hioki
Line reactors can filter out harmonics, thereby improving the power quality of the overall power system. This can prevent some sensitive equipment from accidentally tripping after high heat or high voltage.
Prevent false tripping
Prevent false tripping-sourced: researchgate
When the voltage in the power system is unbalanced or transient, it will cause false tripping, and the line reactor can stabilize the voltage level, helping the entire system run smoothly and avoid false tripping.
Improve power factor and efficiency
Improve power factor and efficiency-sourced: googleusercontent
By reducing the peak current of the drive, the line reactor can improve the power factor of the circuit system, thereby improving energy utilization efficiency and reducing electricity costs.
Protecting motors in long-distance cables
Protecting motors in long-distance cables-sourced: mb-drive-services
When the drive is far away from the motor, voltage spikes and reflected waves will appear in the entire system. Line reactors can minimize this risk, thereby ensuring the stability of long-distance motor use.
Line reactors play an important role in power systems in all industries. Line reactors can be divided into two types according to the connection method:
Shunt reactors
Shunt reactors-sourced: hilkar
Shunt reactors refer to reactors connected in parallel with other equipment in the system. The reactive power variation of the reactor can be achieved by phase-controlled thyristors or by DC magnetization of the core. Its main purpose is to compensate for the capacitive current component and absorb the reactive power generated by the system. In power station systems, shunt reactors are usually connected between the line and the ground, so the reactive power they absorb is fixed and variable. Depending on the configuration of the power system, it can be single-phase or three-phase.
Series reactors
Series reactors-sourced: hitachienergy
Series reactors refer to reactors connected in series with other equipment in the entire system. This connection method can reduce the stress during a three-phase short-circuit fault and minimize the impact of the short-circuit fault on other parts of the system. Series reactors are generally connected between the neutral point and the ground. Therefore, it is also called a neutral-grounded reactor. This installation method can minimize the impact of short-circuit current on the system.
From the perspective of current limiting and neutral point grounding, reactors can be divided into: damping reactors, tuned reactors, grounding transformers, arc extinguishing reactors, and smoothing reactors etc.
From the perspective of equipment structure, line reactors can be divided into:
Air-core reactors
Air-core reactors-sourced: trench-group
Air-core reactors refer to reactors with gap cores.
Based on the installation method, line reactors can be divided into indoor reactors and outdoor reactors etc.
Line reactors can be used in several power systems:
Inverter
Inverter-sourced: prismic
The most common application of line reactors is the inverter. By installing it in the inverter, it can protect the inverter from interference in the current line and prevent the motor from being affected by high-frequency voltage spikes, which can cause the inverter to trip or the motor to overheat. Widespread systems of inverters include air conditioning systems, conveyors, pumps, and compressors.
Long cables between the inverter and motor
Long cables between inverter and motor-sourced: usfull
If the distance between the inverter and the motor exceeds 30m, the output voltage reflection and waveform distortion can damage the motor. In order to reduce these reflected wave lines, reactors can ensure the smooth operation of the motor.
Harmonically sensitive environment
Harmonic sensitive environment-sourced: monolithicpower
Harmonic sensitive environment includes drives, sensitive electronic equipment. Harmonics can cause the entire power system to overheat, cause signal interference, and even cause equipment failure. Therefore, line reactors help to reduce total harmonic distortion, thereby improving the overall power quality.
Renewable Energy Systems
Renewable Energy Systems-sourced: impactclimate
Various renewable energy systems, including solar inverters, wind turbines, and other battery energy storage systems, can use line reactors to help smooth the power output, stabilize DC and AC conversion, and protect various power electronic devices from grid noise.
Industrial Control Panels and OEM Equipment
Industrial Control Panels and OEM Equipment-sourced: ul
Line reactors are now included in many power and control systems to meet EMC compliance and protect the switches of various equipment.
Line reactors can also be used in other industries, including motor drives, power quality, automotive, industrial automation, construction, and infrastructure, etc. These can be designed and manufactured according to your specific requirements.
Line reactor is a general term for inductors and reactors. Its main working mode is:
How Line Reactor Works-sourced: galcoTV
- When the conductor in the power system is energized, it will generate a magnetic field in a certain space. Therefore, all current-carrying conductors are inductive.
- However, the inductance generated by a long straight conductor is small, so the magnetic field generated is not strong.
- The line reactor is a hollow line reactor made of a wound solenoid. This can produce a larger inductance. Such a coil is also called an iron core line reactor. And impedance and reactance.
- When the current passes through, the reactor can compensate for the influence of the distributed capacitance of the long line, thereby limiting the output harmonic current and increasing the output high-frequency impedance, thereby protecting the power equipment.
Line reactors are generally available in two impedance ratings, 3% or 5%:
What Are The Line Reactor Impedance Ratings-sourced: eecoonline
3% impedance means it can absorb power line spikes and motor current abuse and prevent nuisance tripping of drives or circuit breakers.
5% impedance means it is suitable for reducing harmonic currents and frequencies, thereby reducing motor operating temperature and noise.
To ensure safe and efficient operation of your circuit system, you need to consider the following factors to select the line reactor that is suitable for you:
Confirm the voltage and rated current of your circuit system
Confirm the voltage and rated current of your circuit system-sourced: samtec
The line reactor must reach the rated value of 480V, 30A to operate safely under load, and needs to have stronger filtering and voltage smoothing functions in a high-harmonic environment. After confirming the voltage and rated current of your system, the higher the impedance, the better the protection effect of the reactor.
Choose the input reactor or the output reactor
Choose input reactor or output reactor-sourced: emheater
The installation location and functions provided by the input reactor and output reactor are different. The input reactor is generally installed before the inverter. Its main function is to protect the inverter from the influence of grid voltage spikes and harmonic distortion. The output reactor is installed between the inverter and the motor. Its main function is to protect the motor from the influence of long cables.
Verify the installation environment
Verify the installation environment-sourced: hitachienergy
You need to thoroughly check and evaluate whether your installation environment is suitable for installing line reactors. This includes the installation method, the type of cabinet, and the cooling method. Does your dustproof or moisture-proof cabinet meet the standards? Does the installation environment have sufficient airflow or forced air cooling?
Check the compliance of the line reactor and whether it has compliance certification
Generally, high-quality reactors have CE standards and RoHS standards.
Custom requirements
If your system is non-standard and the cabinet space is small, you need to consider special customization requirements. These include customized voltage and current ratings and compact footprint design, as well as integrated thermal sensors and protection functions.
What Are The Load Reactors-sourced: strikinglycdn
The load reactor is also called the output reactor. It is mainly installed between the inverter and the motor to protect the motor. It increases the inductance of the load and reduces the impact of reflected waves.
The main benefits of load reactors include:
Reduce the effects of reflected waves
Reduce the effects of reflected waves-sourced: encrypted
Long wires are needed between the drive and the motor to protect the motor. Load reactors are more useful when your motor wiring is longer than 100 feet.
Increase load inductance
Increase load inductance-sourced: theengineeringmindset
Load reactors help restore the load inductance to a level that the drive can handle.
Choosing a line reactor that is compatible with your power system can provide healthier protection for your line and extend the service life of the equipment. After learning about line reactors through this article, you can better understand the requirements of voltage, current, impedance and circuit system layout. If you need more equipment and knowledge about reactors in the future, you are welcome to consult us.
