Reliability Analysis of Load-Sharing K-out-of-N System Considering Component Degradation

Abstract EN

The K-out-of-N configuration is a typical form of redundancy techniques to improve system reliability, where at least K-out-of-N components must work for successful operation of system.

When the components are degraded, more components are needed to meet the system requirement, which means that the value of K has to increase.

The current reliability analysis methods overestimate the reliability, because using constant K ignores the degradation effect.

In a load-sharing system with degrading components, the workload shared on each surviving component will increase after a random component failure, resulting in higher failure rate and increased performance degradation rate.

This paper proposes a method combining a tampered failure rate model with a performance degradation model to analyze the reliability of load-sharing K-out-of-N system with degrading components.

The proposed method considers the value of K as a variable which is derived by the performance degradation model.

Also, the load-sharing effect is evaluated by the tampered failure rate model.

Monte-Carlo simulation procedure is used to estimate the discrete probability distribution of K.

The case of a solar panel is studied in this paper, and the result shows that the reliability considering component degradation is less than that ignoring component degradation.