Modelling of Station of Pumping by Variable Speed

International audienceAn increased energetic efficiency will make it possible to decrease the factory operating costs and hence to increase productivity.The centrifugal pumps are largely used because of their relatively simple operation and of their purchase price. One analyses thorough requirements imposed by the pumping plants is decisive.It is important to keep in mind the fact that the pumps consume approximately 20% of energy in the world. They constitute the possibility for the most significant efficiency improvement. They can reach their maximum effectiveness only with one pressure and a given flow. The approach suggested makes it possible to adapt with accuracy and effectiveness of system output of the industrial process requirements. The variable speed drive is one of best and effective techniques studied to reach this objective. The appearance of this technique comes only after the evolution obtained in the field of power electronics systems precisely static inverters as well as the efforts made by the researchers in the field of electric drive systems. This work suggested is the result of an in-depth study on the effectiveness of this new technique applied for the centrifugal pumps. 1. Introduction. Due to their operating closer to the optimum, variable speed pumping plants are reliable: energy saving, maintenance intervals saving and hence stop costs reduction. According to the structure of the user, it is also possible, by the intermediary of a speed regulation, to reduce the number of the pumps size. The complexity of a centrifugal pump drive makes its study and design difficult as well as during its normal operation. To overcome this difficulty, one generally carries out simplifications: linearization of some characteristics, addition of inertias of all the moving parts to that of the engine, etc. in function of the objectives of modelling, these simplifications can give satisfactory results[3]. With the aim of reducing the costs and risks of bad operations in the evaluation phase and training of complex systems, the use of data-processing tools for digital simulation seems a justifiable intermediate stage between the theoretical study and the tests on real installations. Pump centrifuges P-102.b P-102.a several tools (specialized or not) for simulation are used in the field of the machines electric and of the power electronics [4] [5]:ATOSEC5, EMTP, SPICE, SIMNON, MATLAB, etc. [3].2. Modelisation of the System of Pumping.Figure 1 presents prone pumping plant the "of study»; unit of ammonia NH3 of the Asmidal factory-Annaba-Algeria and more precise the centrifugal pumps P-102 intended for fed the units of nitric acid, acid nitrate and of acid phosphates in product ammonia "to see figure 1"