New development in relay protection for smart grid

Baohui Zhang,Zhiguo Hao,Zhiqian Bo

doi:10.1186/s41601-016-0025-x

Baohui Zhang, Zhiguo Hao + Show 1 more

Open Access

https://doi.org/10.1186/s41601-016-0025-x

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Abstract

This series of papers report on relay protection strategies that satisfy the demands of a strong smart grid. These strategies include ultra-high-speed transient-based fault discrimination, new co-ordination principles of main and back-up protection to suit the diversification of the power network, optimal co-ordination between relay protection and auto-reclosure to enhance robustness of the power network. There are also new development in protection early warning and tripping functions of protection based on wide area information. In this paper the principles, algorithms and techniques of single-ended, transient-based and ultra-high-speed protection for EHV transmission lines, buses, DC transmission lines and faulty line selection for non-solid earthed networks are presented. Tests show that the methods presented can determine fault characteristics with ultra-high-speed (5 ms) and that the new principles of fault discrimination can satisfy the demand of EHV systems within a smart grid.

Highlights

Relay protection is the key to the safe operation of a power system
The functions of relay protection have been developed along with enhancements to electrical power systems and the implementation techniques developed with the related areas of science and technology
Ensuring the function of a relay to satisfy the requirements of the development of the smart grid and perform the protection task with high reliability, involves a series of key technical issues

Summary

Introduction

Relay protection is the key to the safe operation of a power system. The functions of relay protection have been developed along with enhancements to electrical power systems and the implementation techniques developed with the related areas of science and technology. The above mentioned device and algorithms can be used to develop ultra high speed protection relays to identify the fault location and fault type based on detecting and processing the high frequency components of such fault transients.

Results

Conclusion