Adaptive ground distance protection for UPFC compensated transmission lines: A formulation considering the fault resistance effect

• This paper presents a ground distance protection mathematical deterministic formulation.
• The formulation is developed using phase coordinates.
• To suit both balanced and unbalanced systems.
• As well as UPFC compensated systems.
• Fault impedance estimation and compensation.

This paper presents a mathematical deterministic adaptive distance protection formulation for UPFC compensated transmission lines. The proposed formulation is developed using a phase component approach and considers and compensates for various UPFC operation conditions and non-zero fault resistances. The proposed methodology is completely adaptive and independent of system characteristics (such as changes in transmission line impedances) or operating conditions (such as different load conditions and controlled reference parameters). Moreover, the proposed formulation uses local and remote end voltage and current signals as input data. The comparative test results demonstrate potential beneficial aspects of the proposed formulation for real-time applications.