Improving accuracy of state estimator solutions

• Main Author: Liu, Yao
• Other Authors: Gooi Hoay Beng
• Format: Final Year Project
• Language: English
• Published: 2015
• Subjects: DRNTU::Engineering::Electrical and electronic engineering
• Online Access: http://hdl.handle.net/10356/64720
• Institution: Nanyang Technological University

In power systems, state estimation is one of the core functions of energy management system (EMS). And its function is based on a variety of measurement information to estimate the current state of the power system. To protect the safety of modern power system, it depends on the energy management system (EMS), and the plenty of functions in EMS can be divided into two major sections: analysis of real-time changes for online applications and analysis of typical trend for off-line applications in power systems. State estimation can be regarded as the basis for most of the advanced online application software. If the results of state estimation are not accurate, and the subsequent analysis and calculation will not get accurate results as well. Hence, we can understand the importance of a correct state estimator solution. In this project, the main objective is to improve the accuracy of state estimator solutions and eliminate the unexpected errors in the state estimation. Corresponding troubleshooting methods have been conducted, such as collating the MTALAB codes with state estimation algorithm, measuring on the inductance and line impedance, checking the admittance matrix, modifying the parameters of the system and so on. In addition, the relationship between the state estimation algorithm and MATLAB codes was explained and verified. By figuring out how the parameters affect the state estimated results, state estimation has been well understood. Another objective is to solve the compatibility problems. By following the principle of trace-back, the problems have been fixed by the debugging LabVIEW program. A Simple Error Handler was added to find out the source of the problems. In the process of finding the errors, Energy Management System (EMS) flow was investigated, which is in the order of State Estimation, Bad Data Detection and Identification, Automatic Generation Control and Optimal Power Flow. Apart from the two objectives, Microgrid Topology was verified and a correspondence table was built regarding to the orientation of bus numbering system. The recommendation for future work would also be discussed at the end.