Key Applications of Transformers in Electrical Devices
When current is transferred from one circuit to another without any physical contact between the circuits, we use a practical transformer. It also does not allow changing the phase and the frequency. Depending on the type, there are various uses of a transformer. The transfer of electricity from one circuit to another through the electromagnetic induction process is known as a practical transformer. It is used to increase and decrease the voltage in the circuit. The increase in voltage is called “step up” and a decrease in voltage is called the “step down” method. A transformer that increases the voltage between primary and secondary winding is called a step-up transformer, and that decreased voltage is called a step-down transformer.
Transformer Parts and Construction
In a transformer, various parts are used for operations, such as the core, windings, brushes, vents, and many more. These individual parts boost up and help to work the transformer overall. To quote simply, in a transformer, there are two coins that are wounded on the same iron core. The material of the core is magnetic and is usually laminated. The coils are bounded and electrically insulated, but due to the presence of iron core, they get magnetically induced. The primary coil P is where the voltage is applied and the secondary coil S is where the output is drawn out. And this entire setup is kept in an environment suitable for better insulation and cooling purposes.
The transformer has three main parts:
Transformer Primary Winding
Transformer Magnetic Core.
Transformer Secondary Winding.
Transformer Primary Winding: When it is connected to an electrical pole, it produces electric flux.
Transformer Magnetic Core: A close circuit will be formed when the reductant path will be linked with the secondary winding. The magnetic flux produced by the primary winding that will flow through this reductant path creates a magnetic circuit.
Transformer Secondary Winding: The flux passes through the core that is linked with the secondary winding. The flux is produced by the primary winding. On the core, the wind is done with the same flux and gives the output of the transformer.
(Image will be Uploaded soon)
Application and Uses of a Transformer
Power Transformers:
The transformers which are used for high voltage power transfer applications (more than 33 Kilovolt) are called Power Transformers. They are usually very big. They can occupy a wide area of space.
Distribution Transformers:
The transformers which are used to distribute the generated power to distant locations are called distribution transformers. At a low voltage, it is used for distributing electricity that is less than 33 Kilovolt in industry. It also distributes 220-440 V for household purposes.
Measurement Transformers:
The transformer which helps in measuring voltage, current, power, etc. is called a Measurement Transformer.
Transformers are classified according to the place of use, and are as follows:
Indoor Transformers:
The transformer that is covered with roofs and shelters, just like the industry types, is called an indoor transformer.
Outdoor Transformers:
The transformer that is mainly kept outside and is used as distribution type transformers is called an outdoor transformer.
Types of Transformers
There are types of transformers based on different parameters, such as the construction or usage for the input requirements.
1. Transformer based on the Phase Requirements:
Depending upon the phase, there are two types of transformers: Single-phase transformer and three-phase transformer.
2. Transformers based on the Core Design:
Based on the design of the core, there are three types of transformers: shell-type transformer, core type transformer, and berry type transformer.
3. Transformers based on the Core Type:
Based on the type of the core, there are two types of transformers: air-core transformer and ferromagnetic or iron core transformer.
Three-phase Transformer over Single-phase Transformer
Transformers are used to transfer electrical energy from one circuit to another. The mechanism behind the working of transformers is electromagnetic induction. However, depending upon the phase, there are two types of transformers: single-phase transformer and three-phase transformer.
Advantages of three-phase transformer over single-phase transformer are:
Comparatively lesser cost
Lighter in weight
Delivers more power
Is highly efficient
List space is required
Easy installation
Less maintenance required
Transportation is comparatively easy
Easy to assemble and repair
A single-phase power can be derived from a three-phase power, whereas the reverse cannot be done.
There are various advantages of using a three-phase transformer. But there are also some limitations that might be caused by using a 3 phase transformer over a single-phase transformer, which are as follows:
The costs are higher as construction is more.
Repair and maintenance take up a large amount of money.
If an emergency occurs at any particular site, then the entire area gets shut down.
If the system is shut down, then immediate maintenance cannot be done.
If there is any error, then the entire unit needs to be replaced, but in a single-phase transformer, only the particular ones can be replaced.
FAQs on Uses of Transformer in Daily Life and Technology
1. What is the main purpose of a transformer in an electrical circuit?
The main purpose of a transformer is to change the voltage and current levels of an alternating current (AC) supply without changing its frequency. It operates on the principle of mutual induction to either increase the voltage (a step-up transformer) or decrease the voltage (a step-down transformer), which in turn decreases or increases the current, respectively.
2. What are the different applications of step-up and step-down transformers?
Step-up and step-down transformers have distinct applications based on their function:
- Step-Up Transformers: These are used to increase voltage. Common applications include in power plants to transmit electricity over long distances with minimal power loss, in microwave ovens to generate the high voltage needed for the magnetron, and in X-ray machines.
- Step-Down Transformers: These are used to decrease voltage. They are widely used in power distribution networks to lower the voltage for safe use in homes and industries. You can also find them in consumer electronics like mobile phone chargers, doorbells, and laptop power adapters.
3. How are transformers used in everyday life and home appliances?
Transformers are essential in our daily lives. The power reaching our homes from the grid is stepped down by a transformer in the local substation to a safe level (e.g., 220V-240V). Inside the home, many devices use small transformers. For example, your mobile phone charger or laptop adapter uses a step-down transformer to convert the high wall-socket voltage to the low DC voltage required to charge the battery. They are also used in doorbell circuits and inside appliances like televisions and audio systems.
4. Why are transformers crucial for long-distance power transmission as per the CBSE Class 12 syllabus?
Transformers are crucial for efficient long-distance power transmission because they help minimise power loss. At power generation plants, a step-up transformer increases the voltage to a very high level (e.g., thousands of volts). According to the power formula (P = VI), this drastically reduces the current. The power lost as heat in transmission lines is given by I²R. By reducing the current (I), the power loss is significantly minimised. Before the electricity reaches consumers, a series of step-down transformers reduce the voltage back to a safe, usable level.
5. Besides power grids, where are transformers used in specific industrial or medical applications?
Beyond the power grid, transformers have specialised uses. In industrial settings, welding transformers are used to provide a very high current at a low voltage, which is necessary to generate the heat required for welding. In medical science, isolation transformers are used in equipment like ECG and EEG machines to protect the patient from electrical shock by isolating the device from the main power line. They are also used for impedance matching in signal processing and audio circuits.
6. How does the use of a laminated soft iron core in a transformer contribute to its efficiency?
The laminated soft iron core is vital for a transformer's efficiency for two main reasons. First, soft iron is a ferromagnetic material with high permeability, which confines and guides the magnetic flux from the primary to the secondary coil with minimal leakage, reducing energy loss. Second, the core is laminated, meaning it's made of thin, insulated sheets. This design significantly increases the core's resistance and breaks the path for large eddy currents, which are a major source of energy loss as heat. This directly improves the transformer's overall operational efficiency.
