The Modelica Association Modelica 2006, September 4 th – 5 th Pressurized Water Reactor Modelling with Modelica Annick Souyri Daniel Bouskela EDF/R&D 6 quai Watier, F-78401 Chatou Cedex, France annick.souyri@edf.fr daniel.bouskela@edf.fr Bruno Pentori Nordine Kerkar EDF/SEPTEN 12-14 avenue Dutriévoz, 69628 Villeurbanne, France bruno.pentori@edf.fr nordine.kerkar@edf.fr Abstract In order to optimize and validate the design and the operation of its nuclear power plants facilities, EDF (Electricité de France) uses a proprietary tool called LEDA to perform static and dynamic simulation at the system level. EDF wishes to replace LEDA by state-of-the-art off-the-shelf tools, mainly to reduce maintenance cost while keeping up with the latest trend in modeling and simulation technology. To validate the feasibility of replacing LEDA by Modelica based tools, several benchmarks models have been chosen, that represent the variety of engi- neering studies made at EDF. The objective of this work is to show that these tools are fit to dynamic modeling and simulation of a PWR plant. To that end, a reference LEDA model of such plant has been successfully translated into Modelica and simulated using Dymola. The results of the Dymola simulation experiments are compared to those obtained with LEDA. This paper describes the structure of the Modelica model, and the modeling and the numerical difficul- ties encountered during the translation and simula- tion process. 1 Introduction For more than 20 years, EDF has been using model- ing and simulation at the system level for the sizing, design verification and validation, and the operation of its nuclear and conventional thermal power plants. To that end, EDF has developed and maintained since the early 80’s a modular code called LEDA. LEDA is used for static (plant sizing) and dynamic studies (modeling and simulation of the normal or incidental plant transients). It is an efficient tool, that has a complete model library and can solve direct and inverse problems. But, because of its now ageing architecture, it cannot keep up with the latest trend in modeling and simulation technology. So, to improve the efficiency of its simulation tools while reducing their cost, EDF is studying the feasi- bility of using state-of-the-art readily available tools instead of LEDA code. The replacement tools should at least have the same capabilities as LEDA, i.e. have an open component library, be able to perform static and dynamic stud- ies, compute steady states and solve inverse prob- lems. They also should not induce an excessive de- pendency upon the tool providers. Modelica based tools offer such characteristics. That is why they are considered as good candidates to re- place LEDA. In order to evaluate the feasibility to replace LEDA by Modelica based tools, benchmark cases have been selected, which cover the variety of studies made at EDF. The first case to be studied was the quasi-2D modeling of a steam generator [1]. The next indus- trial case in the nuclear field to be studied, and ob- jective of this work, is the dynamic modeling of a 1300 MW PWR power plant (P4). The P4 LEDA model is a reference model used to study the behavior of the plant wrt. the power grid solicitations. In particular, it is useful for verifying the design of the control system against important transients, such as the house load operation. This paper shows how the P4 LEDA model was translated into Modelica and tested with Dymola. 127 Pressurized Water Reactor Modelling with Modelica