Reliability optimisation using harmony search algorithm under performance and budget constraints

Abstract : The redundancy optimisation problem is a well-known NP hard problem that involves the selection of components (elements) and redundancy levels to maximise system reliability, given different system-level constraints such as cost and performance. This paper presents an efficient algorithm based on the Harmony Search Algorithm (HSA) to solve this optimisation problem. The HSA is a new nature-inspired algorithm which mimics the improvisation process of music players. The problem considered in testing our algorithm is limited to the binary series-parallel system, where the problem consists of a selection of elements and redundancy levels. The proposed approach has the advantage to allow power components with different parameters to be allocated in power systems. To allow fast reliability estimation, a Universal Moment Generating Function (UMGF) method is applied. A computer program has been developed to implement the UMGF and the HSA. An illustrative example is presented.