Abstract:

This paper analyzed the defects in current protection configuration of voltage regulating transformer of rectifier unit and the necessity of configuring differential protection, proposed solutions of differential protection, and focused on the fundamental principles of differential protection of voltage regulating transformer that based on gear tracking. For the possible exceptions of gear collection, several gear checking methods were proposed. When the gear checking failed, it would switch to high constant value differential protection mode, and which could ensure the reliability of differential protection.

Key words: voltage regulating transformer, rectifier transformer, differential protection, gear