Formulation of the power flow problem in human readable form for translation into an efficient solver

Sammanfattning: Power systems are complex systems that need supervision and control to operatereliably and safely. Energy Management Systems (EMS)/SCADA provides the necessary aids formonitoring and control of power systems. Since power ow forms the basis of power system analysis,power ow solvers (PFS) are an integral part of EMS/SCADA systems. With the evolving powersystems new challenges appear which force new functionalities and requirements on EMS/SCADA,these in turn are translated into requirements on the PFS. Current EMS/SCADA utilize PFS thatwere developed in the 1970's and 1980's. Maintaining and upgrading these PFS to meet currentrequirements is ever more dicult. The development of an advanced, ecient and easier to maintainPFS is therefore necessary. This thesis focuses on the development of a power ow solver that iseasier to maintain, ecient and scalable. To achieve this a programming language that can meet theperformance requirements of a PFS and formulate the power ow problem at a higher abstractionlevel is required. Several programming languages are reviewed while they fulll some aspects theyare decient on other requirements. Therefore the open EMS programming language (OPL) isdeveloped, which can describe the power ow problem at a higher programming level. OPL is usedto model a small power system network, which is solved to obtain the power ow solution. Theexisting model is extended to include ratio tap changers and switched shunts, to proof the conceptthat additional equipment is added with relative ease.