A Study On Algorithms And Software Developments For Probabilistic Security Evaluation Of Bulk Power Systems

In the dissertation a more accurate algorithm for probabilistic security evaluation is proposed.The algorithm is based on system state probability rather than failure event probability. Not only the single or double failure of line or transformer but also the multiple failures caused by protection misoperation can be modeled to get the probabilitstic security indices. The effect on security of bus arrangements is also studied.Security evaluation on large power systems is of great importance in practice. A new probabilistic security evaluation software named PSD-PRE is developed using Visual FORTRAN and Visual C++. It achieves the calling of PSD-BPA, which makes the calculation results more exquisite. The software can be used in reliability evaluation of lager power system and the manual workload is reduced greatly. Data-in of this software is flexible, and power flow and stability format data of BPA can be directly used. The probability indices of the system losing stability including the classified probability indices by the causation of the system losing stability are given. Various acceleration calculation methods are adopted to alleviate the calculational burden of reliability evaluation, improve the efficiency and the practicability of the software.The software PSD-PRE has been tested using IEEE-RTS 9, IEEE-RTS 79 and ShanxiPower Network and the test results show that PSD-PRE is valid and available.