The Power Flow Calculation And Power Optimization Of Smart Grid

Electric energy is the most convenient and significant energy of modern society. The research on rationally using the power energy, improving the power quality and reducing energy has been hot for resent years. The power flow calculation is to calculate the steady operation of power system, it determines the operation status of the power system by using the given operating conditions and ways of network connection, it’s the basis of power system analysis, which provides the basic data for power optimization. This thesis puts a weight on the analyzing and researching the power flow calculation and power optimization of the power system.The power flow calculating methods of traditional power grid are researched in the first part in this thesis, of which the back/forward sweep method based on branch current is for the typical radial network of distribution system, and Newton-Raphson(N-R) method using polar coordinates is for the typical loop network of transmission system. Both of the two methods are applied in a certain distribution system and transmission system in Tongliao area.In the following chapters, the power flow calculation of smart grid with distributing generation is analyzed. The network interface model of distributing power is analyzed in the first place, and then the wind turbine is modeled and researched, Taking the distribution and transmission system with wind turbines in Tongliao area for instance, this thesis applied the improved back/forward sweep method and N-R method to the system, the simulation result proved that the appropriate switching in of distributing power can raise the voltage of some nodes and reduce the line loss.The method of dynamically distributing the load increment for the analysis of dynamic power flow of the power grid is presented in the thesis. This method analyses the dynamic power flow caused by load variation by using the power increment of the nodes, the simulation performed proved that this method is simpler and faster than traditional power flow calculation.At last, the grid power optimization is researched. First, the model of power optimization is described. Then the traditional algorithms of active power optimization with the minimum power cost as objective function and the reactive power optimization with minimum active power losses as objective function are analyzed respectively. At last, the active power optimization simulation is done on the IEEE14node system using the multi-agent model with navigator in accordance with the equivalent increment principle, and preferable optimization effect is obtained.