基于自适应SFLA算法的LQR附加阻尼控制器设计

针对含有电压源型换流器高压直流(VSC-HVDC)的交直流系统愈发凸显的低频振荡问题,提出了一种基于改进自适应混合蛙跳(SFLA)算法优化的线性二次型最优方法来设计附加阻尼控制器,以此来抑制振荡。该方法采用最小二乘-旋转不变技术(TLS-ESPRIT),辨识出系统的对应振荡模态和降阶模型。针对该模型运用线性二次最优控制法并引入状态观测器,求出带观测器的控制器表达式。采用改进自适应SFLA算法对权矩阵进行优化,设计线性二次型最优控制器使其控制效果最优。在PSCAD验证。仿真结果显示,这种控制器相比于传统线性二次最优控制器具有更好的鲁棒性和控制效果,控制器也较易设计。

Design of LQR additional damping controller based on adaptive SFLA algorithm

For the low frequency oscillation problem of AC/DC transmission system with voltage source converter based high voltage direct current(VSC-HVDC),a linear quadratic optimal method based on the improved adaptive shuffled frog leaping algorithm(SFLA)is proposed to design the damping controller to suppress the oscillation.Firstly,the method applies the total least squares-estimation on signal parameters via rotational invariance techniques(TLS-ESPRIT)to identify the corresponding oscillation modes and reduces order model of the system.Then,the linear quadratic optimal control method is applied to the model and introduced to the state observer.Then,the improved adaptive SFLA algorithm is used to optimize the weight matrix for the model,which makes the linear quadratic optimal controller optimal.Finally,a fourmachine two-zone model is built in PSCAD show that the controller has better robustness and control effect compared with traditional linear quadratic optimal controller,and the controller is easier to design.