Contingency-constrained optimisation method for operating urban power grids with flexible switching stations

Abstract

This study presents a multi-objective operation optimisation model for urban power grids with flexible switching (FS) stations to comprehensively improve system security and reliability. In the proposed model, uncertainties associated with load variation and component failures are considered. Moreover, constraints after a feeder or transformer N − 1 contingency are preliminarily formulated. The operation problem optimises the apparent power of feeder section loading. The combination of normal boundary intersection and sequential quadratic programming is employed to solve the non-linear optimisation model. A case study carried out on a test 75-feeder distribution grid with FS stations demonstrates the effectiveness of the proposed model and solving method. Compared with conventional distribution loadability, the optimal load distribution solution obtained in this study provides a trade-off between system security and reliability. The coordinated operation optimisation method is suitable for urban smart distribution grids featured by distribution automation and large-scale interconnections.

Keywords

• power distribution reliability
• power grids
• quadratic programming
• nonlinear programming
• optimisation
• power system security
• load distribution
• smart power grids
• urban smart distribution grids
• coordinated operation optimisation method
• optimal load distribution solution
• FS stations
• test 75-feeder distribution grid
• nonlinear optimisation model
• sequential quadratic programming
• normal boundary intersection
• feeder section loading
• apparent power
• operation problem
• component failures
• load variation
• system security
• multiobjective operation optimisation model
• flexible switching stations
• urban power grids
• contingency-constrained optimisation method