Abstract: In order to diagnose the fault units in the system, this paper firstly uses the Mussels Wandering Optimization algorithm to solve the system-level fault diagnosis problem, proposes an efficient fault diagnosis algorithm—the Mussels Wandering Optimization Fault Diagnosis（MWOFD）. Combining with the characteristics of system-level fault diagnosis it proposes the Mussels Wandering encoding and initialization, and designs the new fitness function according to equation constraint conditions that the diagnostic model has to meet, at the same time it optimizes the existing binary mapping algorithm. Finally, the new algorithm is compared with AD-FAFD algorithm, FAFD algorithm and EAFD algorithm experimentally. Experimental results show that MWOFD algorithm improves the diagnostic accuracy and efficiency of diagnosis effectively.

Key words: system-level fault diagnosis, equation model, mussels wandering optimization algorithm, Mussels Wandering Optimization Fault Diagnosis（MWOFD） algorithm

摘要： 为了诊断出系统中的故障单元，首次将贝壳漫步优化算法用于解决系统级故障诊断问题，提出一种高效快速的诊断算法——MWOFD诊断（Mussels Wandering Optimization Fault Diagnosis）算法。结合系统级故障诊断的特点，设计了个体化编码及初始化的方法，并根据诊断模型所满足的方程约束重新设计了适应度函数，同时对二进制映射算法进行优化。最后将新算法与AD-FAFD算法，FAFD算法和EAFD算法进行实验对比，结果表明：MWOFD算法有效地提高了诊断正确率和诊断效率。

关键词: 系统级故障诊断, 方程模型, 贝壳漫步算法, 贝壳漫步诊断（MWOFD）算法