Travelling wave sampling data sharing solution in distribution substation based on IEC61850

The signal of travelling wave has the merit of immunity to system oscillation, transition resistance, CT saturation and the neutral point operation modes; it has been widely applied in field of fault detection and protection. Especially in isolated neutral grounded wind farm distribution network, the algorithm using multiple-bay travelling wave´s information can exclusively achieve the fast fault feeder selection and tripping. However, travelling wave sampling frequency tends to reach 500 to 1000 times of that in algorithms with power frequency signal. The direct of travelling wave sampling data sharing in process bus would produce the communication block, and weaken the security of whole substation automation. To solve this problem, the performance of communication in process bus is theoretically analyzed and simulated in this paper, the communication requirement of travelling waves is quantified, and then a feasible scheme is proposed with data pre-processing and fault characteristic abstraction moving forward into the merging unit. Simulations prove its validity. The work in paper can promote the wide application of travelling waves in substation based on IEC61850.