(1923) Energy Loses in Transformer (Flux Leakage, Hysteresis Loss, Eddy Current Loss, Coper Loss) BEE

Transformers: Energy Losses

Introduction to Transformers

• Transformers are electrical devices composed of a core and windings that transfer electric power between two circuits through electromagnetic induction.

• Typically, a transformer has:

  • Core: Made from ferromagnetic material.

  • Primary Winding: Source of input power (gemaakt with copper wire).

  • Secondary Winding: Receives the induced power output.

• Example: Supplying 100 kilowatts to the primary winding results in only about 95 kilowatts being passed to the secondary winding due to energy losses.

Types of Energy Losses in Transformers

1. Flux Leakage

• Definition: Loss of magnetic flux from the primary winding that does not link with the secondary winding, resulting in lost power.

• Explanation:

  • An alternating current in the primary winding produces changing magnetic field lines.

  • Only about 80% of the magnetic flux is successfully transferred to the secondary winding, leading to 20% loss.

• Minimization Strategy: Use of ferromagnetic materials (like soft iron) to construct the core to reduce leakages.

2. Energy Loss Due to Resistance of Winding

• Mechanism of Loss: Energy is lost as heat due to the resistance present in the copper windings when current passes through. The loss can be calculated using the formula:

[ P = I^2RT ]

• Loss Proportion: If 20% of energy is lost to resistance, then it affects the total power transmitted.

• Resistance Reduction Strategies:

  • Increase the cross-sectional area of wire to decrease resistance.

  • Use thicker wires on the side where current is higher:

    • In Step-Up Transformers: Thick wire on primary side (high current).

    • In Step-Down Transformers: Thick wire on secondary side (high current).

3. Hysteresis Loss

• Definition: Loss occurring from the repeated magnetization and demagnetization of the core material during alternating current supply.

• Loss Mechanics: Changes in magnetic field lines result in energy loss due to hysteresis.

  • Hysteresis loss is represented graphically, with the area inside the hysteresis loop depicting energy lost.

  • Steel results in higher hysteresis losses compared to soft iron; hence, soft iron is preferred due to lower energy losses.

4. Eddy Current Loss

• Definition: Currents induced in the core material due to changing magnetic fields, which create loops (eddy currents) that generate heat.

• Loss Explanation:

  • Eddy currents flow in circular paths within the core and produce heat, leading to power losses.

• Minimization Method:

  • Use laminated cores to limit the eddy currents:

    • Plates of the core are placed with insulating layers in between, restricting eddy currents to the surfaces of the plates, which minimizes overall heat loss.

Conclusion

• The four types of energy losses in transformers (flux leakage, winding resistance loss, hysteresis loss, and eddy current loss) impact the efficiency of power transmission.

• Utilizing appropriate materials and design considerations is essential to mitigate these losses, ensuring maximum power transmission.