基于改进遗传算法的系统参数辨识

System Parameter Identification Based on Improved Genetic Algorithm

传统的遗传算法在解决具体优化问题时存在着收敛速度慢和容易早熟的缺点。针对系统参数辨识,提出了一种改进的遗传算法。通过合理选择复制策略、改进适应度函数计算方法,克服了早熟现象,保证了种群的多样性,避免了后期适应值接近而导致收敛速度过慢。通过该算法对典型二阶系统的传递函数进行参数求解,在信噪比较大的情况下,得到几乎无偏的估计。实验结果证明了该方法的有效性。

Traditional genetic algorithms have convergence speed and premature easily in solving specific optimization problems,in case of system parameters identification,an improved genetic algorithm is presented.By selecting reasonable replication strategy,and improving the fitness function calculation,overcomes the prematurity,the diversity of the population is ensured,avoid slow convergence which is resulted by the close fitness value in the later time.The parameters of typical second-order system transfer function by the algorithm are solved.In the case of larger SNR,the estimation is obtained to be almost no bias.Experimental results show the effectiveness of the method.