【摘要】 稳定可靠的并网控制策略是提高光伏逆变器故障穿越能力的关键,对锁相技术的研究尤为重要。提出一种改进型一阶广义积分锁频环FOGI-FLL(frequency-locked loop based on first order generalized integrator)技术,首先利用滑动平均滤波器MAF(moving average filter)滤除电网电压中的谐波分量,消除谐波对FOGI-FLL的影响,再利用FOGI-FLL进行基波正、负序分离。仿真结果表明:在发生谐波畸变的电网中,所提出的方法能够在电网电压不平衡、频率突变和相位跳变的故障情况下,准确提取出电网电压的基波正、负序分量,并快速跟踪电网频率和相位。更多还原

【Abstract】 Stable and reliable grid connected control strategy is the key to improve the fault ride through capability of photovoltaic inverter, which is especially important for the research of phase lock technique. This paper proposes an improved frequency-locked loop based on first order generalized integrator(FOGI-FLL). First through moving average filter(MAF), it can eliminate the harmonics and the impact of harmonics effectively in grid voltage. Then, the positive and negative sequence voltage are separated by FOGI-FLL. Simulation results show that the proposed method can accurately extract the fundamental positive and negative sequence components of the grid voltage, and rapidly track the frequency and phase of the grid in the harmonic distortion grid, when the grid voltage is unbalanced, the frequency changes and the phase jump occurs.更多还原