基于梯度下降法的单相幅相锁相环优化设计

基于目标函数优化的思想设计了单相幅相锁相环系统(1MPLL),详细讨论了系统中参数的设计方法。为了提高系统的谐波抑制能力,以最近时域区间系统偏差的积分构造目标函数,通过梯度下降法分析了目标函数的最速下降方向,推导出锁相环系统的非线性状态方程,从而对输入信号属性进行估计。为了进行系统性能分析和参数设计,对系统非线性状态方程在平衡点进行线性化处理,采用根轨迹理论对系统参数进行设计。系统能在各种电能质量问题下(如幅值突变、频率波动、相位突变,尤其是谐波污染)对输入信号的属性进行快速精确估计,为并网电力电子设备的检测和控制提供有效、可靠的基准。仿真实验验证了系统设计的正确性和良好性能。

Optimal Design for Single-phase Amplitude-phase-locked Loop Based on Gradient Descent Method

A single-phase amplitude-phase-locked loop(1MPLL) system based on objective function optimization ideasis designed and the design method of system parameters is discussed in detail. In order to improve the harmonic suppression capability, 1MPLL constructs the objective function based on integration of system deviation in the most recent time interval, the steepest descent direction is analyzed using the gradient descent method. And the nonlinear state equation of phase-locked loop system is derived to estimate the properties of the input signal. In order to carry out system performance analysis and parameter design, the system nonlinear state equation is linearized at the equilibrium point and the system parameters are designed with the root locus theory. The properties of the input signal are estimated quickly and accurately by IMPLL for a variety of power quality problems (such as amplitude mutation, frequency fluctuation, phase change, especially harmonic pollution), providing effective and reliable baseline for the detection and control of grid power electronic equipment. Simulation and experiment results verify the correctness of the system design and good system performance.