【摘要】 可实施电流开环控制的本质电流源拓扑的并网逆变器,对锁相精度和动态响应的要求比电流闭环控制的并网逆变器的要求更高,因此提出一种适用于新能源并网的高速、高精度的软件锁相算法。通过构造旋转坐标系,将数字鉴相器及数字滤波器的时域差分方程转化为旋转坐标系下低频脉动的频域量,并采用等效于滑模控制的分象限变步长的Bang-Bang控制,实现对电网电压相位的快速锁定。数控振荡器采用基于内部模型的增量式算法,保证对电网电压的频率的高精度锁定。用Lyapunov方法分析了该算法的稳定性及收敛条件,讨论了算法的优点与推广应用。更多还原

【Abstract】 Higher resolution and faster response are required for open-loop current control inverters than for closed-loop current control inverters.A high efficient digital phase locked loop(DPLL) was implemented for grid-connecting applications.The algorithm was implemented on the rotating d-q model with Bang-Bang control to regulate the phase angle of grid voltage through only 4 multiplications and a logic look-up table.The frequency was regulated in the digital controlled oscillator(DCO) by internal mode incremental algorithm.Stability and convergence analysis was guaranteed with Lyapunov method and further applications were discussed.更多还原