安军,乔雪婧,王玉鹏.考虑锁相环影响的多逆变器并联接入弱电网稳定性分析[J].电测与仪表,2021,58(8):146-153. AN Jun,QIAO Xuejing,WANG Yupeng.Stability Analysis of Multi-inverter Parallel Access to Weak Power Grid Considering the Influence of Phase-Locked Loop[J].Electrical Measurement & Instrumentation,2021,58(8):146-153.
考虑锁相环影响的多逆变器并联接入弱电网稳定性分析
Stability Analysis of Multi-inverter Parallel Access to Weak Power Grid Considering the Influence of Phase-Locked Loop
The phase-locked loop plays a vital role in ensuring that the grid-connected current and voltage are synchronized when the inverter is connected in parallel to the grid. The dynamics of the power electronics and its interaction with the grid under the weak grid are obviously complicated. Stability issue. Starting from the control system of multi-inverter grid-connected, an impedance analysis model considering the influence of control loops such as phase-locked loop and current regulator is established. The inverters are considered for other inverters and their AC grids. The interaction between the two sets of inverters is proposed. The influence of grid strength, phase-locked loop parameters and the number of inverters on the stability margin of the system is analyzed. According to the obtained stability criterion, the maximum number of inverters that can be connected in parallel under different grid strengths is given. Finally, A model of multiple inverters connected in parallel to the weak grid was built on PSCAD to verify the correctness of the results.
