METHOD FOR OBTAINING SYMMETRIC POWER TRANSFER COEFFICIENTS UNDER SIMULTANEOUS CHANGE OF SOURCES AND LOADS IN AC POWER NETWORKS

摘要

The present invention belongs to electric power engineering field, relates to a method for obtaining a set of symmetric power transfer coefficients under simultaneous change of sources and loads in AC power networks, which comprises the steps of: firstly establishing a linear function of a lossy branch transferred power in terms of buses voltage angles according to a nonlinear function of a branch transferred power, parameters and operation features of the AC power network; then establishing symmetric linear functions of buses injection powers of power sources and loads in terms of buses voltage angles by combining the linear function of the lossy branch transferred power in terms of buses voltage angles and buses injection powers of power sources and loads, in turn establishing symmetric linear functions of buses voltage angles in terms of buses injection powers of power sources and loads; and finally obtaining the symmetric power transfer coefficients from buses injection powers of power sources and loads to the lossy branch transferred power under simultaneous change of sources and loads by using the linear functions just mentioned above. The obtained set of symmetric power transfer coefficients is unique, follows electric circuit laws, is applicable for the practical situations that power sources and loads change at the same time and transmission losses need considering in the AC power network, and truly reflects the substantive characteristics of the power transfer from bus injection powers to branch transferred powers.