Grid synchronization is one of the key technologies for the stable and reliable operation of grid-connected photovoltaic systems. In high-proportion renewable energy

the power grid faces problems such as voltage disturbance

voltage imbalance

harmonic distortion

DC offset

and so on. To this end

a new phase-locked loop based on a synchronous reference frame phase-locked loop and a pre-loop moving average filter is proposed. It employs a phase compensation method to correct the phase-locked error when there is a frequency deviation. At the same time

considering the phase-frequency coupling characteristics of PMAF

an angular frequency compensation method is designed to improve the dynamic performance of the phase-locked loop. A small signal model is established

and a stability analysis is conducted. Following that

a fault detection module is designed to realize the input and removal of the two compensation branches to adapt to different working conditions. Simulations verify the effectiveness of this new phase-locked loop under complex grid conditions such as phase jump

frequency deviation and voltage distortion. Finally

the transient performance test of the new phase-locked loop is carried out in the high-proportion renewable energy generation model. The results indicate that the phase-locked loop can lock the grid voltage phase as quickly as possible

avoid the oscillation and divergence of voltage and current

and is conducive to the rapid and stable recovery of the system after a fault.