FAULT DIAGNOSIS

Methods and systems for fault diagnosis are described. The methods are in particular, although not necessarily exclusively, for the detection of faults in multi-component systems, typically power plant, whose performance is characterised by a series of indirectly measurable performance parameters. The methods proposed are based on “optimisation techniques”, involving the optimisation of an objective function to obtain an estimate of performance parameters and operating parameters. In one aspect, a method is proposed that takes account of measurement biases. In another aspect, a method for optimising an objective function is proposed, which adopts a unique Evolution Program approach in which a population of possible solutions is sub-divided into a number of groups.