Fault Current Analysis Method of Inverter-interfaced Renewable Energy Sources With PLL and Current Inner Loop Transient Processes
To cope with the challenge of the high proportion of renewable energy access to protection principles in the new power system,it is urgently required to analyze the fault characteristics of renewable energy.Most renewable energy is connected to the grid as an inverter-interfaced renewable energy source(IIRES),and the phase-locked loop(PLL)serves as a key control loop for IIRES.The transient process of PLL directly affects the fault characteristics of IIRES.This paper proposes a fault current analysis method for IIRES that considers the transient process of both PLL and the inner current loop.Starting from the influence of PLL on Park transform,this paper clarifies the impact of PLL on fault current and simplifies the impact of PLL on the transient process of the inner current loop.The fault current analysis formula related to PLL and inner current loop parameters is theoretically derived to analyze the influencing factors of fault current quantitatively.The fault current is divided into three stages based on the transient characteristics of the inner current loop and PLL,and the duration in each stage is clarified.The effectiveness of the proposed method is validated by comparing it with the simulation waveform.
PLLinverter-interfaced renewable energy sourcesfault current analysistransient current
万方数据
维普
