In this note, we are going to learn about the Asymmetrical Faults in Electrical System. Also Types of Asymmetrical Faults and Causes of these faults. Welcome to Poly Notes Hub, a leading destination for Diploma Engineering Notes.
Author Name: Arun Paul.
What are Asymmetrical Faults?
An asymmetrical fault, also known as an unbalanced fault, happens in electrical systems when the fault currents flowing through the system’s phases are not balanced. Asymmetrical faults produce different currents in each phase, as opposed to symmetrical faults, which have the same magnitude and phase angle.
Types of Asymmetrical Faults
There are three types of these Faults –
- Line to Line Faults
- Line to Ground Faults
- Phase to Phase Faults
1. Line-to-Line Faults
This sort of failure happens when two conductors in a multiphase system come into contact with one another. Line-to-line faults can cause imbalanced fault currents to flow through the affected phases.
2. Line to Ground Faults
A line-to-ground fault occurs when one of the multiphase system’s conductors comes into touch with the ground or a grounded object. This sort of fault causes an imbalance in fault currents between the phase of the fault and the ground.
3. Phase to Phase Faults
Phase-to-phase faults occur when a fault arises between two phases of a multiphase system, causing imbalanced fault currents to flow through the affected phases.
Causes of Asymmetrical Faults
- Phase Imbalance: In a multiphase system, unequal phase loading can result in asymmetrical faults. If one phase has much greater current than the others, it might cause imbalanced fault currents during a fault state.
- Insulation Failure: Asymmetrical faults can result from a breakdown of insulation between conductors or between a conductor and ground. When insulation fails, it can cause phase-to-phase or phase-to-ground faults, resulting in an imbalance of fault currents.
- Equipment Failure: Asymmetrical problems can occur when electrical equipment, such as transformers, motors, or generators, malfunctions or fails. Short circuits or phase-to-ground faults in the equipment might cause imbalanced fault currents.
- Corrosion or Deterioration: Asymmetrical failures are more likely to occur when electrical components, such as joints, insulation, and connectors, corrode or deteriorate with time.
- Environmental Factors: Asymmetrical faults can result from environmental factors including lightning strikes, strong winds that cause conductor contact, or interference from vegetation. Unbalanced fault currents may arise from phase-to-ground or phase-to-phase faults caused by these exogenous causes.