Network reduction in power system analyses

iii iv PREFACE I would like to thank my parents for supporting me all the time. At last, I would like to appreciate my fellow Nan Qin study together with me over the years. And, those technical and philosophical discussions in power system filed impel me to accomplish the project. ABSTRACT The future integration of large offshore wind farm requires a more advanced external grid for testing the transient behavior of the wind farm. A reduced entire power network system was proposed replace the present external grid which calculated by Thevenin equivalent. Based on the literature study the different technique of the dynamic network reduction, the coherent based equivalent method will be implemented in a real power system model. The model established in the power system analysis tool DIgSILENT PowerFactory. While, the Network reduction module inside the software will be tested by some study cases. The systemized procedure has been introduced and realized in the model simulation. An automatic network reduced program is developed.