提出一种两级优化原则,整体可靠度分配给子系统采用“花费”最小原则,子系统可靠度分配给单元采用考虑“权重”的优化原则。并且采用两种优化算法,即用能简化求解过程的目标协调法、二维混合协调法和AGREE法对可靠度优化分配进行求解,从而使系统全局可靠度优化分配的效果更好。 A two-level optimization principle is proposed. The overall reliability is assigned to the subsystem using the “cost” principle, and the subsystem reliability is assigned to the unit using the optimization principle considering “weight”. And two kinds of optimization algorithms are adopted, that is, the objective coordination method, the two-dimensional hybrid coordination method and the AGREE method which can simplify the solving process are used to solve the optimal distribution of reliability, so that the global reliability is optimally distributed.