New smart multi-ended differential solution for power networks

Chee Pinp Teoh, Joao Jesus, Simon Richards, Hengxu Ha
2018 The Journal of Engineering  
Line current differential protection is based on Kirchhoff's current law calculating the vector sum of the currents from each line end to detect faults in the protected zone. For synchronisation of the current vectors, time compensation with a pingpong measurement of the propagation time delay is used. A new smart multi-ended differential protection is presented in this study, which includes a new capacitive current compensation technique. The protection relay is scalable for any transmission
more » ... stem topology including hybrid lines. The protection is based on RMS values calculated from samples making it immune to frequency variations and the protection operating time is sub-cycle. The protection uses an accurate algorithm for capacitance current compensation with a distributed line parameter model, where only the impedance and admittance per unit are required. This technique has an error <1% even considering transients in the algorithm. The need to provide connections to new renewable generation has increased the need for a multi-ended line differential protection. This new smart protection concept is a step forward in providing reliable, cost effective and integrated protection for these new network topologies.
doi:10.1049/joe.2018.0236 fatcat:aqgta62abnempk45eb7yz7r2fi