Optimal placement of harmonic measurement unit based on ant-algorithm for distribution network

Key words:  distribution network  ant-algorithm  phasor measurement unit(PMU)  observability degree  redundancy

Abstract:

An optimal placement of the harmonic measurement can effectively improve the feasibility and accuracy of the harmonic state estimation for a distribution network. The principle of placing the distribution network harmonic measuring unit is determined based on the characteristics of the distribution network. Using distribution network topology, a mathematical model is derived to calculate the node-voltage-state observability. The PMU optimal placement of the mathematical model is established with comprehensive considerations of the node-voltage-state observability degree and redundancy. Ant-algorithm is proposed to solve the optimal placement problem of the harmonic measuring unit, which can give a variety of schemes to meet the same optimization goal for the planning, and can be designed to choose the optimal solution according to the real situations. The results show that the ant-algorithm is effective for the optimal placement of the harmonic measurement. The redundancy of nodes is effectively reduced and the number of observable nodes is sufficiently increased by the optimal placement of the PMU.