In three-phase power systems, imbalance is caused by faults, uneven loads or equipment problems Question caused. Symmetric component method analysis: positive sequence indicates normal operation, three-phase Equal amplitude and mutual difference of 120 ° rotate in the same direction; Negative sequence triple equal amplitude counter-rotation, It is caused by asymmetric fault, causing the equipment to heat up; Zero sequence three identical phases, Common in ground faults, affecting protection and safety.

The arc detection system mainly consists of an arc monitoring unit, a control unit, an optical detector .It consists of a detector, a current detector and a current transformer. Control unit receive .High sensitivity optical signal and current signal, quickly and reliably judge whether to trigger Circuit breaker. Optical fiber has high-speed transmission and anti-electromagnetic interference characteristics, which is reasonable . Imagine signal transmission medium. Light sensor collects arc through bare fiber loop Light is transmitted to the receiver through the optical fiber and converted into an electrical signal to inform the control system System to achieve instant response.

When voltage drops, current increases to maintain power output according to P=VxIxPF. This can cause overheating, overloading, and reduced efficiency in motors.

In power system, protective relay is the key link to ensure that it can accurately and reliably detect and remove faults