A Multi-objective Planning of Transmission Line Balance Degree Based on Power Flow Entropy Theory

The equilibrium degree of transmission lines in the multi-objective planning of power grid is studied in this paper. The main purpose of the study is to ensure the economy and improve the balanced distribution of active power flow of transmission lines, furthermore increase the adaptability of transmission lines in the future power grid. The problem is mainly focus on the single-level of line load rate, in researching on the distribution balance of active power flow in transmission lines. Three indexed, which are line load rate power flow entropy, active loss rate power flow entropy and transmission efficiency power flow entropy, are defined in this paper. The weighted sum of the three indexes is defined as the balance factor of active power flow distribution in transmission lines. This factor is used in transmission network planning to improve the overall balance of active power flow distribution in transmission lines. On this basis, a multi-objective programming model with minimum economic cost and maximum equilibrium factor of transmission network is established. The model is solved by using multi-objective bacterial colony chemotactic algorithm (BCC) and optimal compromise solution method. The results verify the superiority and rationality of the proposed method and model.