一种改进的同伦BP算法及其在故障诊断中的应用研究

为克服标准BP算法中存在的网络学习收敛速度慢、容易陷入局部极小等问题，引入同伦算法，提出了一种将同伦论与快速BP算法结合的改进算法，并采用二进制结构表示输出模式矩阵。最后以柴油机燃油系统为例，对其中的几种故障进行诊断研究。仿真结果表明此方法既能快速收敛，又能大大提高避免陷入局部极小的能力。

Improved Homotopy BP Algorithm and Application in Fault Diagnosis

In order to overcome the problems of slow rate of convergence and falling easily into local minimum in BP algorithm, a new improved homotopy BP algorithm is put forward. It transfers the identity matrix of output mode in common use into the binary system. Taking fuel system of diesel engine as example, the faults that appeared common are diagnosed adopting the improved algorithms. The result of simulation shows that the improved algorithm has advantages of fast convergence and avoiding falling into local minimum.