Practical Transformer: Modelling the Real World - 3 | Module 3: Introduction to Magnetism and Transformers | Basics of Electrical Engineering
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3 - Practical Transformer: Modelling the Real World

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Construction Details of Transformers

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0:00
Teacher
Teacher

Let’s discuss the construction of transformers. Can anyone tell me what the core does?

Student 1
Student 1

The core provides a path for magnetic flux, right?

Teacher
Teacher

Exactly! It enhances coupling between the windings. What materials do you think are used for the core?

Student 2
Student 2

I read they often use silicon steel to reduce losses.

Teacher
Teacher

Great point! Silicon is indeed added to increase resistivity, lowering eddy current losses. Why do we use lamination in transformer cores?

Student 3
Student 3

To minimize the eddy currents as well, right?

Teacher
Teacher

Correct! Laminations interrupt the flow of eddy currents. This helps in improving efficiency. So, what do we use for windings?

Student 4
Student 4

Copper, because it's a good conductor.

Teacher
Teacher

Yes! And sometimes aluminum is used for cost savings. Remember, with great conductors come considerations for insulation. What do you think insulation is used for?

Student 1
Student 1

To prevent electrical shorts and ensure safety?

Teacher
Teacher

Exactly! We must insulate separate windings and the core. In summary, the core, winding materials, and insulation are critical for transformer performance. Let’s move to how we model transformers using equivalent circuits.

Introduction & Overview

Read a summary of the section's main ideas. Choose from Basic, Medium, or Detailed.

Quick Overview

This section explores the practical aspects of transformers, emphasizing their real-world applications and deviations from ideal behavior due to material properties.

Standard

The section delves into practical transformer construction, analyzing the core, windings, insulation, thermal management, and the importance of equivalent circuits in modeling transformer performance. It underscores how these factors influence efficiency, voltage regulation, and the overall reliability of transformers in electrical systems.

Detailed

Practical Transformer: Modelling the Real World

This section focuses on the practical implications of transformer design and operation, recognizing that real-world transformers deviate from ideal models due to physical characteristics, construction materials, and operational environments. Key details covered include:

  1. Construction Details: This subsection highlights the core's role in efficient magnetic flux management, with materials like silicon steel. The importance of lamination to minimize eddy current losses is emphasized, alongside the organization of windings and the insulation system, which ensures reliability and safety.
  2. Equivalent Circuit: Practical transformers can be modeled using equivalent circuits that include parameters for winding resistance and reactance. This modeling allows for meaningful predictions of performance under various operating conditions.
  3. Open-Circuit and Short-Circuit Tests: These tests are essential for assessing transformer performance. The open-circuit test determines core losses while the short-circuit test assesses copper losses, enabling a clearer understanding of efficiency; these components feed into calculations about voltage regulation and overall efficiency.
  4. Performance Metrics: This covers the importance of understanding transformer losses (copper and core), voltage regulation ratios under different load conditions, and efficiencies that track operational effectiveness. Real-world transformers are evaluated not only on their design but also in their response to varying loads and environmental factors.

Overall, this section equips students to understand the practical design considerations engineers must tackle in transformer applications, laying the groundwork for optimizing performance.

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Construction Details: The Physical Components

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3.1. Construction Details (Core, Windings, Insulation, Cooling): The Physical Components

3.1.1. Core:

  1. Function: To provide a highly permeable, low-reluctance path for the mutual magnetic flux, ensuring efficient coupling between windings.
  2. Material: Constructed from thin sheets (laminations) of high-grade silicon steel. Silicon is added to steel (typically 0.5% to 4.5%) because it significantly increases the electrical resistivity of the core material. This increased resistivity is crucial for reducing eddy current losses.
  3. Lamination: The core is not a single solid block of steel. Instead, it's built up from thin sheets (typically 0.35 mm to 0.5 mm thick for 50/60 Hz transformers) that are individually insulated from each other (e.g., by a thin layer of varnish, lacquer, or oxide). This lamination strategy effectively breaks up the paths for eddy currents. Without laminations, the core would act like a single large conductor, and the induced eddy currents would be enormous, leading to excessive heating and inefficiency.
  4. Grain Orientation (CRGO Steel): For high-performance transformers, Cold-Rolled Grain-Oriented (CRGO) steel is often used. This steel is processed to align its crystal grains in the direction of magnetic flux, leading to much higher permeability and lower core losses in that specific direction.
  5. Core Configurations:
  6. Core Type (or Column Type): Characterized by having the windings wound around the central limbs of the laminated core. For single-phase transformers, the limbs are vertical, and windings are placed on two limbs. For three-phase, there are three limbs. Both primary and secondary windings are often split and interleaved on each limb to minimize leakage flux. Offers good natural cooling due to exposed coil surfaces. Favored for high-voltage power transformers.
  7. Shell Type: The core completely surrounds the windings, forming a protective shell. The windings are positioned within a central window of the core. This construction provides superior mechanical protection for the windings and excellent containment of the magnetic flux, naturally reducing leakage flux. Typically used for distribution transformers and smaller units.

Detailed Explanation

This chunk discusses the construction details of practical transformers, focusing on the core, windings, insulation, and cooling systems. The core of a transformer is crucial as it forms a pathway for magnetic flux, made of laminated high-grade silicon steel to enhance efficiency by reducing eddy currents, which are currents induced in the core that can cause heat loss. Laminations, or thin sheets of steel, are used to minimize these losses. Additionally, Grain-Oriented steel is used for better performance by aligning its grain structure for higher permeability. Transformer cores can be column types or shell types, with different configurations impacting cooling and efficiency.

Examples & Analogies

Think of the transformer core like a highway for magnetic flux. Just as a well-constructed road allows cars to travel smoothly without any detours or traffic jams, a well-designed transformer core allows magnetic flux to flow efficiently without energy losses. If the road (core) is wide and straight (laminated and made of high-grade steel), cars (magnetic flux) can travel quickly without stopping to gather excess heat from traffic (eddy currents).

Windings: The Conductors Inside the Transformer

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3.1.2. Windings:

  1. Function: These are the coiled conductors that carry the alternating current and interact with the magnetic flux.
  2. Material: Primarily high-conductivity copper due to its excellent electrical conductivity, ductility, and relatively low resistivity. For very large power transformers, sometimes aluminum is used for its lower cost and lighter weight, although it requires larger cross-sectional areas to achieve comparable resistance to copper.
  3. Primary Winding: The winding connected to the input AC power source (e.g., the utility grid).
  4. Secondary Winding: The winding from which the transformed voltage and current are drawn and supplied to the load.
  5. Arrangement: Windings can be arranged in various ways (e.g., concentric, interleaved, pancake coils) to optimize voltage stress distribution, minimize leakage reactance, and facilitate cooling.

Detailed Explanation

This chunk elaborates on the windings of a transformer. The windings play a key role as they are responsible for converting power from one voltage level to another. Mainly made of copper for its excellent conductive properties, these windings can also utilize aluminum for larger transformers. The primary winding connects to the power source, while the secondary winding supplies the output. Different winding arrangements help manage voltage stress and ensure effective heat dissipation.

Examples & Analogies

You can think of the transformer windings as water pipes in a plumbing system. Just as pipes carry water from one place to another while also being built to withstand pressure, the windings carry electric current at different voltage levels while ensuring minimal energy loss. The arrangement of the pipes (or windings) can affect how efficiently the water (or electricity) can flow and how well the system can handle pressure (voltage).

Insulation and Cooling: Safety and Effectiveness

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3.1.3. Insulation System:

  1. Function: Absolutely critical for safety and reliable operation. It electrically isolates:
  2. Individual turns of a winding from each other.
  3. Layers of windings from each other.
  4. The primary winding from the secondary winding.
  5. All windings from the laminated steel core.
  6. Materials: A combination of materials is used:
  7. Solid Insulation: Pressboard, Kraft paper, wood, mica, ceramics, synthetic polymers. These are used as barriers, spacers, and wrapping materials for conductors.
  8. Liquid Insulation: Transformer oil (mineral oil) is the most common. It serves a dual purpose: it acts as a dielectric (excellent insulator) and also as a highly effective coolant by convection. Synthetic fluids (e.g., silicone oils) are used in fire-sensitive environments.
  9. Gaseous Insulation: Air is a basic insulator. For high-voltage dry-type transformers, gases like SF6 (sulfur hexafluoride) are sometimes used.

Detailed Explanation

In this section, the importance of insulation and cooling systems in transformers is discussed. Insulation is crucial to prevent electrical failures and ensure safety by isolating different parts of the transformer from one another. Various materials are utilized, including solid insulators like pressboard and liquid insulators such as transformer oil, which not only insulates but also cools the device. This ensures that high temperatures from electrical currents do not damage the transformer, keeping it running efficiently and safely.

Examples & Analogies

Imagine insulation like the protective casing around electrical wires in your home. Just as this casing prevents unwanted electrical contact and potential shocks, the transformer’s insulation keeps electrical components separate, ensuring safe operations. The cooling system can be viewed like a fan or air conditioning in a house, keeping the rooms (or in this case, the components) from overheating and functioning effectively.

Cooling Systems: Maintaining Thermodynamic Balance

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3.1.4. Cooling System:

  1. Function: To dissipate the heat generated within the transformer due to its losses (copper losses and core losses). Effective cooling is essential to maintain the operating temperature of the insulation below its thermal limits, preventing degradation and extending the transformer's lifespan. Overheating can lead to insulation breakdown and catastrophic failure.
  2. Common Cooling Methods (specified by standards like IEC/IEEE):
  3. Oil Natural Air Natural (ONAN): The most common method for medium-sized transformers. Heat from the windings and core is transferred to the insulating oil by natural convection. The heated oil rises, flows through cooling radiators (fins) where it dissipates heat to the ambient air by natural convection, then cools and sinks, creating a continuous circulation loop.
  4. Oil Natural Air Forced (ONAF): Similar to ONAN, but fans are used to force air over the cooling radiators, significantly increasing the rate of heat dissipation. This allows for higher loading or smaller radiator size for a given rating.
  5. Oil Forced Air Forced (OFAF): Both the oil and the air are circulated by pumps and fans, respectively. This highly effective method is used for very large power transformers where natural convection is insufficient.
  6. Oil Forced Water Forced (OFWF): Oil is circulated by a pump through an external heat exchanger, where it is cooled by forced circulation of water. This is typically used for extremely large transformers in power plants, where a readily available water source is present.

Detailed Explanation

Cooling systems are discussed as integral to a transformer’s operation, aiming to remove heat generated from copper and core losses to protect the equipment from overheating. Various methods are employed, with Oil Natural Air Natural (ONAN) being the most common; it uses the transformer oil to absorb heat and circulate it through a radiator for cooling. For larger transformers, additional methods like forced air or water cooling offer more effective heat dispersion to handle higher operational loads.

Examples & Analogies

Think of a transformer’s cooling system like the radiator in a car. Just like a radiator helps dissipate engine heat to keep the vehicle running smoothly, the transformer cooling system ensures that the device operates within safe temperature limits. If the radiator fails, the car overheats; similarly, if a transformer’s cooling system is inadequate, it could fail due to excessive heat.

Equivalent Circuit: Modelling Imperfections

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3.2. Equivalent Circuit (Referenced to Primary/Secondary): Modelling Imperfections

Concept:

The equivalent circuit of a practical transformer is a simplified electrical circuit that models all the non-ideal characteristics and losses of the transformer using discrete circuit components (resistances, reactances). This allows engineers to analyze and predict the transformer's behavior under various operating conditions.

Components and Their Representation:

  1. Primary Winding Resistance (R1): Represents the ohmic resistance of the copper (or aluminum) wire used in the primary winding. It accounts for the I2R copper losses in the primary.
  2. Primary Leakage Reactance (X1): Represents the inductive reactance due to the "leakage flux" that links only the primary winding but does not pass through the core to link with the secondary winding. This leakage flux does not contribute to mutual induction and causes a voltage drop in the primary circuit.
  3. Core Loss Resistance (Rc or Rfe): This resistance, placed in parallel with the magnetizing reactance, models the power dissipated as heat in the magnetic core due to hysteresis and eddy current losses. It carries the active component of the no-load current.
  4. Magnetizing Reactance (Xm): This reactance, placed in parallel with the core loss resistance, models the reactive power (and thus the magnetizing current, Im) required to establish and maintain the main alternating magnetic flux in the transformer core. It carries the reactive component of the no-load current.

Detailed Explanation

This section introduces the equivalent circuit of transformers to represent their non-ideal characteristics. It includes circuit components like primary winding resistance, which accounts for losses in the primary winding; primary leakage reactance, which accounts for flux that does not link the secondary winding; core loss resistance to model losses in the core, and magnetizing reactance which maintains the required magnetic field. Understanding these components allows engineers to effectively analyze a transformer’s performance and identify areas for improvement.

Examples & Analogies

Consider the equivalent circuit like the blueprint of a building. Just as a blueprint outlines all the essential structural elements and shows how they relate, the equivalent circuit represents the various electrical parameters and losses of a transformer, enabling engineers to ensure that everything functions as intended. If changes are needed, a detailed blueprint allows for careful planning and inspection, just as understanding the equivalent circuit helps make transformer adjustments for optimal performance.

Open-Circuit and Short-Circuit Tests: Evaluating Transformer Performance

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3.3. Open-Circuit Test (No-Load Test): Unveiling Core Losses and Excitation Parameters

Purpose:

This test is designed to accurately determine the core losses (Pc or Piron) of the transformer and to derive the parameters of the excitation branch (Rc and Xm) of its equivalent circuit. Core losses are considered relatively constant regardless of the transformer's load.

Principle:

When a transformer is open-circuited on the secondary side, the primary current drawn is only the small no-load current (IOC). This current is primarily used to establish the magnetic flux in the core and to supply the core losses. Because the no-load current is very small (typically 2% to 5% of rated current), the copper losses (I2R) occurring in the windings are negligible compared to the core losses. Therefore, the power measured during this test is almost entirely the core loss.

Procedure:

  1. Connection: The transformer is connected such that one winding (typically the low-voltage (LV) side) is connected to a variable AC voltage supply (at rated frequency), and the other winding (the high-voltage (HV) side) is left open-circuited (no load connected, open terminals).
  2. Measurements: As the voltage of the variable AC supply is gradually increased to the transformer's rated voltage for the LV side, simultaneous readings are taken from:
  3. A voltmeter (VOC): Measures the applied no-load voltage (equal to the rated LV voltage).
  4. An ammeter (IOC): Measures the no-load current drawn by the primary (LV) winding.
  5. A wattmeter (POC): Measures the total real power consumed during the test.

Detailed Explanation

This section explains the open-circuit test, which measures core losses and evaluates the excitation parameters of a transformer when the secondary side is disconnected. During this test, the primary windings only draw a small no-load current to maintain magnetic flux in the core. The test measures voltage, current, and power consumption to derive core loss resistance and magnetizing reactance, aiding engineers in assessing the transformer’s performance under no-load conditions.

Examples & Analogies

Think of an open-circuit test like testing a light bulb without turning it on while checking how much current it uses to stay ready. You can see how much power it consumes even when it’s not illuminating anything. In a transformer, the open-circuit test reveals how much energy is lost in core losses, preparing engineers to understand the device's efficiency, much like knowing how much standby power a device consumes.

Short-Circuit Test: Understanding Copper Losses

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3.4. Short-Circuit Test: Quantifying Copper Losses and Equivalent Impedance

Purpose:

This test is performed to determine the full-load copper losses (Pcu) and the combined equivalent series resistance (Req) and equivalent series reactance (Xeq) of the transformer windings, referred to the side where the test is conducted. Copper losses are variable losses, dependent on the square of the load current.

Principle:

When the secondary winding is short-circuited, a very small voltage applied to the primary side is sufficient to circulate full-load currents. At this very low applied voltage, the magnetic flux in the core is negligible. Consequently, the core losses (which are voltage-dependent) become extremely small and can be effectively ignored. Therefore, the power measured during this test is almost entirely due to the I2R losses (copper losses) in the primary and secondary windings.

Procedure:

  1. Connection: The transformer's LV winding is short-circuited using a thick conductor (zero impedance connection). The HV winding is connected to a variable AC voltage supply (at rated frequency).
  2. Measurements: The voltage of the variable AC supply is gradually increased from zero until the ammeter connected in the HV circuit reads the rated full-load current of the HV side. Simultaneous readings are taken from:
  3. A voltmeter (VSC): Measures the small applied short-circuit voltage. This voltage is typically a small percentage (e.g., 5-10%) of the transformer's rated voltage.
  4. An ammeter (ISC): Measures the short-circuit current, which is intentionally adjusted to be the rated full-load current of the test-side winding.
  5. A wattmeter (PSC): Measures the total real power consumed during the test.

Detailed Explanation

The short-circuit test is described as a method for measuring full-load copper losses and determining the equivalent impedance of transformer windings when the secondary is bypassed. By applying a small voltage to the primary side while short-circuiting the secondary, engineers only measure copper losses since the magnetic flux in the core is minimal. This is essential for evaluating how the transformer performs under heavy load conditions.

Examples & Analogies

Consider when you need to gauge the maximum load capacity of a power cable by placing a temporary short-circuit on it. Doing this gives you insight into how much current the cable can handle before overheating due to resistance. Similarly, the short-circuit test helps engineers identify copper losses and how efficiently the transformer can run at maximum current, ensuring it remains within safe operating conditions.

3.1.1. Core

  1. Function: To provide a highly permeable, low-reluctance path for the mutual magnetic flux, ensuring efficient coupling between windings.
  2. Material: Constructed from thin sheets (laminations) of high-grade silicon steel. Silicon is added to steel (typically 0.5% to 4.5%) because it significantly increases the electrical resistivity of the core material. This increased resistivity is crucial for reducing eddy current losses.
  3. Lamination: The core is not a single solid block of steel. Instead, it's built up from thin sheets (typically 0.35 mm to 0.5 mm thick for 50/60 Hz transformers) that are individually insulated from each other (e.g., by a thin layer of varnish, lacquer, or oxide). This lamination strategy effectively breaks up the paths for eddy currents. Without laminations, the core would act like a single large conductor, and the induced eddy currents would be enormous, leading to excessive heating and inefficiency.
  4. Grain Orientation (CRGO Steel): For high-performance transformers, Cold-Rolled Grain-Oriented (CRGO) steel is often used. This steel is processed to align its crystal grains in the direction of magnetic flux, leading to much higher permeability and lower core losses in that specific direction.
  5. Core Configurations:
  6. Core Type (or Column Type): Characterized by having the windings wound around the central limbs of the laminated core. For single-phase transformers, the limbs are vertical, and windings are placed on two limbs. For three-phase, there are three limbs. Both primary and secondary windings are often split and interleaved on each limb to minimize leakage flux. Offers good natural cooling due to exposed coil surfaces. Favored for high-voltage power transformers.
  7. Shell Type: The core completely surrounds the windings, forming a protective shell. The windings are positioned within a central window of the core. This construction provides superior mechanical protection for the windings and excellent containment of the magnetic flux, naturally reducing leakage flux. Typically used for distribution transformers and smaller units.
  8. Detailed Explanation: This chunk discusses the construction details of practical transformers, focusing on the core, windings, insulation, and cooling systems. The core of a transformer is crucial as it forms a pathway for magnetic flux, made of laminated high-grade silicon steel to enhance efficiency by reducing eddy currents, which are currents induced in the core that can cause heat loss. Laminations, or thin sheets of steel, are used to minimize these losses. Additionally, Grain-Oriented steel is used for better performance by aligning its grain structure for higher permeability. Transformer cores can be column types or shell types, with different configurations impacting cooling and efficiency.
  9. Real-Life Example or Analogy: Think of the transformer core like a highway for magnetic flux. Just as a well-constructed road allows cars to travel smoothly without any detours or traffic jams, a well-designed transformer core allows magnetic flux to flow efficiently without energy losses. If the road (core) is wide and straight (laminated and made of high-grade steel), cars (magnetic flux) can travel quickly without stopping to gather excess heat from traffic (eddy currents).

--

  • Chunk Title: Windings: The Conductors Inside the Transformer
  • Chunk Text: #### 3.1.2. Windings:
  • Function: These are the coiled conductors that carry the alternating current and interact with the magnetic flux.
  • Material: Primarily high-conductivity copper due to its excellent electrical conductivity, ductility, and relatively low resistivity. For very large power transformers, sometimes aluminum is used for its lower cost and lighter weight, although it requires larger cross-sectional areas to achieve comparable resistance to copper.
  • Primary Winding: The winding connected to the input AC power source (e.g., the utility grid).
  • Secondary Winding: The winding from which the transformed voltage and current are drawn and supplied to the load.
  • Arrangement: Windings can be arranged in various ways (e.g., concentric, interleaved, pancake coils) to optimize voltage stress distribution, minimize leakage reactance, and facilitate cooling.
  • Detailed Explanation: This chunk elaborates on the windings of a transformer. The windings play a key role as they are responsible for converting power from one voltage level to another. Mainly made of copper for its excellent conductive properties, these windings can also utilize aluminum for larger transformers. The primary winding connects to the power source, while the secondary winding supplies the output. Different winding arrangements help manage voltage stress and ensure effective heat dissipation.
  • Real-Life Example or Analogy: You can think of the transformer windings as water pipes in a plumbing system. Just as pipes carry water from one place to another while also being built to withstand pressure, the windings carry electric current at different voltage levels while ensuring minimal energy loss. The arrangement of the pipes (or windings) can affect how efficiently the water (or electricity) can flow and how well the system can handle pressure (voltage).

--

  • Chunk Title: Insulation and Cooling: Safety and Effectiveness
  • Chunk Text: #### 3.1.3. Insulation System:
  • Function: Absolutely critical for safety and reliable operation. It electrically isolates:
  • Individual turns of a winding from each other.
  • Layers of windings from each other.
  • The primary winding from the secondary winding.
  • All windings from the laminated steel core.
  • Materials: A combination of materials is used:
  • Solid Insulation: Pressboard, Kraft paper, wood, mica, ceramics, synthetic polymers. These are used as barriers, spacers, and wrapping materials for conductors.
  • Liquid Insulation: Transformer oil (mineral oil) is the most common. It serves a dual purpose: it acts as a dielectric (excellent insulator) and also as a highly effective coolant by convection. Synthetic fluids (e.g., silicone oils) are used in fire-sensitive environments.
  • Gaseous Insulation: Air is a basic insulator. For high-voltage dry-type transformers, gases like SF6 (sulfur hexafluoride) are sometimes used.
  • Detailed Explanation: In this section, the importance of insulation and cooling systems in transformers is discussed. Insulation is crucial to prevent electrical failures and ensure safety by isolating different parts of the transformer from one another. Various materials are utilized, including solid insulators like pressboard and liquid insulators such as transformer oil, which not only insulates but also cools the device. This ensures that high temperatures from electrical currents do not damage the transformer, keeping it running efficiently and safely.
  • Real-Life Example or Analogy: Imagine insulation like the protective casing around electrical wires in your home. Just as this casing prevents unwanted electrical contact and potential shocks, the transformer’s insulation keeps electrical components separate, ensuring safe operations. The cooling system can be viewed like a fan or air conditioning in a house, keeping the rooms (or in this case, the components) from overheating and functioning effectively.

--

  • Chunk Title: Cooling Systems: Maintaining Thermodynamic Balance
  • Chunk Text: #### 3.1.4. Cooling System:
  • Function: To dissipate the heat generated within the transformer due to its losses (copper losses and core losses). Effective cooling is essential to maintain the operating temperature of the insulation below its thermal limits, preventing degradation and extending the transformer's lifespan. Overheating can lead to insulation breakdown and catastrophic failure.
  • Common Cooling Methods (specified by standards like IEC/IEEE):
  • Oil Natural Air Natural (ONAN): The most common method for medium-sized transformers. Heat from the windings and core is transferred to the insulating oil by natural convection. The heated oil rises, flows through cooling radiators (fins) where it dissipates heat to the ambient air by natural convection, then cools and sinks, creating a continuous circulation loop.
  • Oil Natural Air Forced (ONAF): Similar to ONAN, but fans are used to force air over the cooling radiators, significantly increasing the rate of heat dissipation. This allows for higher loading or smaller radiator size for a given rating.
  • Oil Forced Air Forced (OFAF): Both the oil and the air are circulated by pumps and fans, respectively. This highly effective method is used for very large power transformers where natural convection is insufficient.
  • Oil Forced Water Forced (OFWF): Oil is circulated by a pump through an external heat exchanger, where it is cooled by forced circulation of water. This is typically used for extremely large transformers in power plants, where a readily available water source is present.
  • Detailed Explanation: Cooling systems are discussed as integral to a transformer’s operation, aiming to remove heat generated from copper and core losses to protect the equipment from overheating. Various methods are employed, with Oil Natural Air Natural (ONAN) being the most common; it uses the transformer oil to absorb heat and circulate it through a radiator for cooling. For larger transformers, additional methods like forced air or water cooling offer more effective heat dispersion to handle higher operational loads.
  • Real-Life Example or Analogy: Think of a transformer’s cooling system like the radiator in a car. Just like a radiator helps dissipate engine heat to keep the vehicle running smoothly, the transformer cooling system ensures that the device operates within safe temperature limits. If the radiator fails, the car overheats; similarly, if a transformer’s cooling system is inadequate, it could fail due to excessive heat.

--

  • Chunk Title: Equivalent Circuit: Modelling Imperfections
  • Chunk Text: ### 3.2. Equivalent Circuit (Referenced to Primary/Secondary): Modelling Imperfections