Why Are Reactors Used in Substations?

a blue light in a dark room

Reactors and other electrical components are critical for the proper function of a substation. However, while a reactor is an important asset for any given substation, it’s important to understand how different reactors function as well as their utilities.

Between line reactors, shunt reactors, and transmission lines, it’s clear that different electrical distribution systems and power systems have diverse needs that require specific components to properly address. To understand more about reactive power and how it can impact a given power factor, here’s what you need to know.

What is a reactor?

In short, a substation reactor is essentially a coil that has several turns and fairly high resistance values. Electrical reactors are typically used on a transmission line when it’s necessary to limit currents that could damage a power transformer or other power system. This type of current-limiting reactor often relies on inductive reactance. The additional inductance and reactance are then added to the series which is key to the function of an electrical reactor or series reactor.

Luckily, it’s easier to determine faults in a series reactor since it doesn’t require you to shut down your transformers or generators in the event of a short circuit or other electrical problem. It’s simpler to spot the fault current in your reactor and asses a neutral point for an inductor without having to dismantle an entire power system. This level of reliability makes reactors critical components of many substation electrical systems.

How are reactors used in substations?

Typically, a reactor is applied in two key ways when it’s used in a substation. First, there are common scenarios where a given substation is more lightly loaded. If the substation is lightly loaded but is still at the end of several high-voltage lines, you may wind up with unnecessarily high voltage which can negatively impact the current flow. By using a shunt reactor, you can reappropriate the produced power and then bring down the voltage levels so they remain at tolerable levels which won’t disturb the overall system functionality.

In the second scenario, some substations rely on solid or stiff systems where generated fault currents can overrun circuit breakers and capacitor banks. In this case, a series reactor provides the most reliable as it can offer additional inductive reactance that decreases the fault current to the point that the substation’s circuit breakers can effectively handle it. Without this reactor present, the circuit breakers and other cables could be damaged.

Electrical reactors are also commonly used to lessen circuit flows and restrict them so the flows don’t overshoot the capacity of your circuit breakers. This is useful for saving both time and money as you don’t need to continually replace or repair circuit breakers and cables as long as you have the appropriate line reactor and an electrical switch. However, without a line reactor, you’re liable to spend much more money.

How do you find a reliable manufacturer?

If you’re in an electricity-heavy industry that relies on transformers, magnetic fields, substations, and reactors, it’s important to look for reliability when you’re purchasing components. A good start is to find manufacturers that are IEEE certified. The IEEE is the world’s largest technical professional organization and has high standards for all members. The IEEE is also a not-for-profit organization that is dedicated to ongoing education and the advancement of numerous technical professions. Finding a certified manufacturer is one of the best ways to ensure that you’re purchasing components and materials that are of the highest possible quality.

The value of a reactor in a substation goes beyond both time and money. It can prevent technical complications and streamline operations, too. To keep all your power systems operating within the correct capacity, make sure you’re using top-tier components in your setups.