Load flow is an important tool used by power engineers for planning, to determine the best operation for a power system and exchange of power between utility companies. In order to have an efficient operating power sy...Load flow is an important tool used by power engineers for planning, to determine the best operation for a power system and exchange of power between utility companies. In order to have an efficient operating power system, it is necessary to determine which method is suitable and efficient for the system’s load flow analysis. A power flow analysis method may take a long time and therefore prevent achieving an accurate result to a power flow solution because of continuous changes in power demand and generations. This paper presents analysis of the load flow problem in power system planning studies. The numerical methods: Gauss-Seidel, Newton-Raphson and Fast Decoupled methods were compared for a power flow analysis solution. Simulation is carried out using Matlab for test cases of IEEE 9-Bus, IEEE 30-Bus and IEEE 57-Bus system. The simulation results were compared for number of iteration, computational time, tolerance value and convergence. The compared results show that Newton-Raphson is the most reliable method because it has the least number of iteration and converges faster.展开更多
A quasi-linear relationship between voltage angles and voltage magnitudes in power flow calculation is presented.An accurate estimation of voltage magnitudes can be provided by the quasi-linear relationship when volta...A quasi-linear relationship between voltage angles and voltage magnitudes in power flow calculation is presented.An accurate estimation of voltage magnitudes can be provided by the quasi-linear relationship when voltage angles are derived by classical DC power flow.Based on the quasi-linear relationship,a novel extended DC power flow(EDCPF)model is proposed considering voltage magnitudes.It is simple,reliable and accurate for both distribution network and transmission network in normal system operation states.The accuracy of EDCPF model is verified through a series of standard test systems.展开更多
文摘Load flow is an important tool used by power engineers for planning, to determine the best operation for a power system and exchange of power between utility companies. In order to have an efficient operating power system, it is necessary to determine which method is suitable and efficient for the system’s load flow analysis. A power flow analysis method may take a long time and therefore prevent achieving an accurate result to a power flow solution because of continuous changes in power demand and generations. This paper presents analysis of the load flow problem in power system planning studies. The numerical methods: Gauss-Seidel, Newton-Raphson and Fast Decoupled methods were compared for a power flow analysis solution. Simulation is carried out using Matlab for test cases of IEEE 9-Bus, IEEE 30-Bus and IEEE 57-Bus system. The simulation results were compared for number of iteration, computational time, tolerance value and convergence. The compared results show that Newton-Raphson is the most reliable method because it has the least number of iteration and converges faster.
基金This work was supported in part by the National Key R&D Program of China(No.2016YFB0900100)the National Natural Science Foundation of China(No.51807116).
文摘A quasi-linear relationship between voltage angles and voltage magnitudes in power flow calculation is presented.An accurate estimation of voltage magnitudes can be provided by the quasi-linear relationship when voltage angles are derived by classical DC power flow.Based on the quasi-linear relationship,a novel extended DC power flow(EDCPF)model is proposed considering voltage magnitudes.It is simple,reliable and accurate for both distribution network and transmission network in normal system operation states.The accuracy of EDCPF model is verified through a series of standard test systems.
