Balance of plant modeling with RETRAN and MMS

Detroit Edison has used two dynamic modeling codes, RETRAN and the new Modular Modeling System (MMS) to model a large portion of the balance of plant (BOP) of a BWR nuclear unit. RETRAN is a very basic, detailed and versatile tool for modeling, but becomes cumbersome when applied to large, detailed models such as required for BOP. MMS, however, provides easy-to-use, cost-efficient modules for simulating prescribed BOP components. This comparison effort has provided valuable insight into the transient response of the system and guidance in its operation as well as demonstrating that the simpler MMS code can produce comparable results for the transient selected