为满足家用小功率光伏并网的需求,研究设计了一款2 k W的无变压器型单相光伏并网逆变器。给出了光伏并网逆变器的拓扑结构,详细分析了光伏逆变器的MPPT原理,并通过Boost电路及扰动观察法来实现MPPT过程。在光伏并网过程中,并网逆变器采...为满足家用小功率光伏并网的需求,研究设计了一款2 k W的无变压器型单相光伏并网逆变器。给出了光伏并网逆变器的拓扑结构,详细分析了光伏逆变器的MPPT原理,并通过Boost电路及扰动观察法来实现MPPT过程。在光伏并网过程中,并网逆变器采用了电流的无差拍以及电压电流双循环的控制策略实现了单位功率因数并网,最后通过实验验证该逆变器的可行性。展开更多
According to performance analysis of a three-phase grid-connected inverter mathematical model of a directly-driven wind turbine with a permanent magnet synchronous generator (D-PMSG) under unbalanced network voltage c...According to performance analysis of a three-phase grid-connected inverter mathematical model of a directly-driven wind turbine with a permanent magnet synchronous generator (D-PMSG) under unbalanced network voltage conditions, a dual current-loop control strategy (DCC) oriented on positive voltage and negative current is proposed to inhibit the DC voltage fluctuation. Meanwhile, a notch filter is introduced into the conventional control strategy of a phase-locked loop to complete the low voltage ride through (LVRT) ability of the wind generator. A 1.5-MW D-PMSG with a back-to-back IGBT frequency converter was simulated in the PSCAD/EMTDC environment, and simulation results showed that: the maximum wind power tracking was achieved in this system and the proposed DCC strategy could successfully inhibit the rising aging of DC voltage and enhance the ride-through capability of D-PMSG wind generation system under unbalanced network voltage conditions.展开更多
文摘为满足家用小功率光伏并网的需求,研究设计了一款2 k W的无变压器型单相光伏并网逆变器。给出了光伏并网逆变器的拓扑结构,详细分析了光伏逆变器的MPPT原理,并通过Boost电路及扰动观察法来实现MPPT过程。在光伏并网过程中,并网逆变器采用了电流的无差拍以及电压电流双循环的控制策略实现了单位功率因数并网,最后通过实验验证该逆变器的可行性。
文摘According to performance analysis of a three-phase grid-connected inverter mathematical model of a directly-driven wind turbine with a permanent magnet synchronous generator (D-PMSG) under unbalanced network voltage conditions, a dual current-loop control strategy (DCC) oriented on positive voltage and negative current is proposed to inhibit the DC voltage fluctuation. Meanwhile, a notch filter is introduced into the conventional control strategy of a phase-locked loop to complete the low voltage ride through (LVRT) ability of the wind generator. A 1.5-MW D-PMSG with a back-to-back IGBT frequency converter was simulated in the PSCAD/EMTDC environment, and simulation results showed that: the maximum wind power tracking was achieved in this system and the proposed DCC strategy could successfully inhibit the rising aging of DC voltage and enhance the ride-through capability of D-PMSG wind generation system under unbalanced network voltage conditions.