Fault dissipated energy based fault coupling modelling and reliability evaluation: A case study on wet motor-pump assembly

In mechatronic systems, fault coupling commonly occurs, reflecting the interactive and mutual impact of faults in different components. This interaction culminates in the progressive accumulation of fault dissipated energy, which can eventually lead to system failure. This paper proposes a fault coupling modelling and reliability evaluation method based on fault dissipated energy for mechatronic systems. The fault dissipated energy coupling mechanism is delved and the fault coupling middleware between components is defined based on equivalent parameter. A fault dissipated energy coupling relationship based on fault coupling middleware is then established, along with the corresponding calculation method. Afterwards, a comprehensive reliability evaluation method is developed for mechatronic systems based on their total fault dissipated energy. A case study on a wet motor-pump assembly is conducted to establish and simulate the fault coupling model, and evaluate system reliability. The obtained results show that the proposed model has higher performance than the existing ones, offering a promising avenue for fault mechanism analysis and reliability estimation of mechatronic systems.