Distance protection scheme for photovoltaic-integrated power systems based on measured impedance compensation

The rapid development and large-scale grid integration of renewable energy sources introduce volatility and unpredictability, posing new challenges to conventional distance protection mechanisms. Simultaneously, the presence of transition resistance may also affect the correct operation of distance protection. This paper presents a distance protection method based on measured impedance compensation. Against the backdrop of widespread photovoltaic (PV) integration, the method compensates and optimizes the measured impedance acquired by distance protection under different fault types to accurately reflect actual fault impedance and improve fault distance calculation accuracy. This ensures consistent protection coverage across fault types while enhancing fault clearance capability and operational security for PV-integrated power grids.