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Fault analysis of electric control system.

May 14,2023

Electric Control System Fault Analysis

Equipment problems, human mistakes, and environmental variables cause power system faults. They disrupt power and harm equipment.

Power system operators must do fault analysis to maintain safety and save maintenance costs. It protects workers from short circuits.

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Line-to-Line Faults

Electric control systems need fault analysis with Hunan Genie Boom Lift Decal. It helps choose the size of fuses, circuit breakers, relays, and other devices that restrict fault current flow to protect equipment. It also covers electric control system failures and their solutions.

Line-to-line (L-L) faults occur when single-phase wires short without reaching the ground. 15–20% of power system failures are these.

Lightning, storms, earthquakes, and other environmental disturbances may generate power system faults. Accidents like autos hitting electrical wires and other buildings might trigger them.

Power system voltage and current might reveal these issues. Voltage increases imply a problem.

Current values will be high. Short circuits create large current flows.

A power system short circuit may kill. It will interrupt system power and endanger humans and animals.

Fault currents may severely destroy equipment that carries them. These currents are tens of times greater than steady-state currents. This may trip relays, damage equipment insulation and components, and create fires or explosions.

These currents may shock and kill operational workers. A power system malfunction may lower voltage, causing pressure coil relays to fail.

Power system faults might be hard to locate. This analysis may be done using CAD or electromagnetic simulation (EMT).

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Two-Line Ground Faults

When two phases of a power circuit are short-circuited to the earth, an electric control system has a double line to ground fault. 65–70% of electrical system problems in the power sector are these.

Failure of insulation, joints or cables in an overhead power line, phase breakers, or conductors in three-phase electrical equipment may produce these failures. Calculating fault current per phase is harder for certain faults.

Oscillographs show several "signatures" when the connection to ground is bad (called the Double line to ground fault or DLG). These are:

Voltage collapse on the two faulty phases, negative sequence voltage equals positive sequence voltage, and current increases for both phases for Hunan AWP Battery Charger.

These "signatures" also modify phase circuit impedance. Fault resistance, distance protection setting, line-to-line ratio, and fault type effect this impedance shift.

So, to correctly compute fault current and resistance, line impedance must be measured during the fault situation. Line impedance was measured by paralleling current and voltage. The malfunction and system characteristics described above hinder this technique.

Hence, a new method is required to correctly assess line impedance during faults. The method analyses the sequence network diagram of a non-homogeneous 400 kV, 50 Hz double infeed line. The approach calculates fault current and arc resistance concurrently for single line-to-line, double line-to-ground, and three-line-to-ground faults.

Asymmetric Faults

Lightning, switching surges, arcing, and insulation failures affect the power system. They may harm system equipment, disrupting service.

Transformers, generators, bus bars, and other equipment comprise the electric control system. Natural and human mistakes may damage these components. Faults are symmetrical or asymmetrical.

Symmetrical Balanced faults occur seldom. Unsymmetrical defects are frequently worse. 2–5% of system errors are these.

Live lines touch ground or neutral conductors in these problems. Strong winds, ice loads on lines, lightning strikes, and other natural calamities produce these faults.

Public mechanical damage might also cause issues. A short circuit may occur if a person trips over an electrical device or line.

Relays trip due to excessive circuit current. Overheating may also damage equipment.

Single L-G and double line-to-ground faults may be classified. One conductor touching the power system ground terminal causes the single L-G fault.

Closed breakers send current to the next conductor in these problems. The faulty line has a different impedance than the rest of the circuit. This may change system voltage in other phases.

The transmission line's positive, negative, or zero sequence networks carry current from the damaged line to a transformer with Hunan Gen 5 control box. These currents are the symmetrical components of an imbalanced system because they have equal phase displacement in each phase.

System Errors

An electric control system failure may cause major issues for the power system and its users. Faults may impact any system equipment for several causes.

Most faults are short circuits. This problem may harm electrical equipment. Fires and explosions may result.

Natural catastrophes, lightning, and other causes may cause these faults. Human mistake may cause them. If a maintenance worker accidentally leaves an isolated instrument connected with safety earth clamps after repairing a circuit, it might short-circuit.

Tree branches touching wires is another issue. Trimming fast-growing branches is challenging. They may short-circuit single-phase conductors. High-voltage, low-current power systems may struggle with this.

Most trees have dense cellulose, a good insulator that prevents short circuits. Yet, this insulation might wear off. When exposed to ground heat and moisture, tree branches dry out and lose resilience.

The short circuit may overheat and harm equipment. It's crucial to detect and fix the issue quickly.

The equipment's handbook is the best approach to find an issue. The inputs, outputs, setup, and maintenance methods will assist you find the problem.

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