Compensation

Electric energy plays a major role in every aspect of modern life. However, efficient use of electric energy is not limited to the supply of active power. Another important parameter in electrical systems is reactive energy. Although reactive energy is often overlooked, it has a significant impact on energy efficiency. The management and control of reactive energy are achieved through compensation methods.

Reactive Energy

Reactive energy is a type of energy required for the operation of devices connected to the grid but is not directly consumed. In electrical systems, devices that generate magnetic fields—such as motors, generators, and transformers—require reactive energy. Reactive energy is the energy drawn by electrical loads to create magnetic fields and is returned to the grid. Although this energy does not perform direct work, it is essential for the proper functioning of electrical systems.

Reactive energy, unlike active energy (energy that performs work), is needed merely to sustain the “rotation” of the electrical system. Many devices, when connected to the grid, draw reactive energy, which then flows back to the grid. This type of energy is drawn from the grid together with active energy but is ultimately returned and not directly consumed.

What Is Compensation?

Excessive drawing of reactive energy can cause imbalances and inefficiencies in the electrical grid. This is where compensation comes into play. Compensation is a method used to balance reactive power in electrical systems. Through this method, excess reactive energy is balanced without being returned to the grid. This process is typically carried out using capacitors or shunt reactors.

To illustrate simply, reactive energy can be compared to the sediment in a cup of coffee. Coffee cannot exist without sediment. Although the sediment is never consumed, it remains in the cup and is left behind when the coffee is drunk. This sediment corresponds to reactive energy. The grid does not want this “sediment,” but devices connected to the grid produce it. Compensation is the process of balancing this sediment without harming the grid.

Purpose of Compensation

The primary purpose of compensation is to improve the power factor in electrical systems. The power factor is the ratio of active power to reactive power. A low power factor can lead to reduced energy efficiency, voltage fluctuations in the grid, and excessive heating. Compensation reduces energy losses in the grid, increases efficiency, and extends the lifespan of equipment by preventing these issues.

The main advantages of compensation are:

• Eliminates reactive energy penalties on electricity bills.
• Reduces voltage fluctuations in energy systems.
• Extends the service life of cables and equipment by preventing excessive heating in electrical installations.
• Improves energy quality by reducing the load on the grid.

Types of Compensation

Compensation can be implemented through various methods, each specifically designed for a particular electrical system. The main types of compensation are:

1. Individual Compensation: This method involves using a separate capacitor for each device. In industrial facilities and commercial buildings, capacitors are installed specifically for each electric motor or load consuming reactive power.
2. Group Compensation: Similar load groups are combined and compensated using a single capacitor. This method is used in larger facilities and systems where similar loads are located together.
3. Central Compensation: This method involves compensation at the main supply point of the facility. Here, all loads consuming reactive power are controlled from a single central location.

How Is Compensation Carried Out?

The compensation process is an adjustment made according to the reactive power demand. Reactive power control relays continuously monitor the ratio of sediment to coffee in all three phases and ensure that the required sediment is compensated by capacitors. These relays monitor the voltage level in the grid and activate the necessary capacitors to meet instantaneous reactive power demands.

During the installation of a compensation system, appropriate meters must be used. These meters measure reactive energy and prevent it from exceeding a specified limit. Additionally, regular maintenance of capacitors is essential to ensure their proper operation.

What Happens Without Compensation?

In the absence of compensation, significant efficiency losses occur in electrical systems. Reactive power consumption creates imbalances in electrical systems and causes equipment on the grid to become overloaded. As a result:

• Reactive energy penalties are applied, increasing bills.
• Energy efficiency decreases and system performance is negatively affected.
• Voltage fluctuations increase, placing additional stress on equipment.
• Excessive heating occurs in electrical installations, creating a fire risk.