A Coordination Control For Voltage And Reactive Power Of Power Systems With Distributed Generation And Electric Vehicles

With the continuous development of economy, people’s living standards are constantly improving, people’s demand for power is growing, while the reliability and power supply of power supply higher requirements.Grid scale continues to expand, the large-scale distributed power in continuous access to the grid, a great number of intermittent DG access to distribution network will have a significant influence on the regional power grid; with the rapid development of electric vehicles, access to the grid on the grid caused by the impact of more and more, the operation stability of power grid also put forward higher requirements. The important measure of power quality is the stability of voltage, and the important economic indicator of power enterprise is net loss.. Free of voltage and reactive power coordinated control to improve the voltage stability, reduce network loss and save investment and operation cost etc. as the goal, through adjusting transformer taps and switching device for reactive power compensation measures to voltage stability, the minimum network loss.In this paper, the coordination control of reactive power is analyzed theoretically.. First introduced the advantages of distributed generation and classification, simulated annealing algorithm the calculation steps, theoretically analysis effects of DG’s location and capacity on the voltage of distribution network, then example simulation analysis and verification. Considering the distributed power and non power compensation device access to influence and control of voltage and reactive power coordination, establish corresponding mathematical model, selecting voltage deviation minimum as the objective function, and put forward a mathematical method to solve. Finally, the results of numerical simulation results of single DG reactive power optimization control scheme and multiple DG access without the control scheme of reactive power optimization.Analysed access of electric vehicles and reactive power compensation device of voltage and reactive power coordinated control, based on established corresponding mathematical model, the selection of voltage deviation minimum as the objective function, and the mathematical method is proposed to optimization calculation is carried out, finally, through numerical simulation, the single node access electric cars for reactive power optimization control effect and multiple access node electric vehicles for reactive power optimization control are analyzed in theory.Through the ideal model, the influence of the distributed power supply and the electric vehicle access to the network is analyzed theoretically.. Then consider the access of distributed power supply, electric vehicles and reactive power compensation device of voltage and reactive power coordinated control, establish corresponding mathematical model, selecting voltage deviation minimum as the objective function, and the mathematical method is proposed to optimization calculation is carried out, finally, through the example simulation analysis of electric vehicles in the fast charge, in charge and slow charge three mode, distributed power and reactive power compensation device of no coordination of voltage and reactive power optimization control.Based on a large number of simulation example calculation and simulation analysis of DG’s location and capacity on the voltage of distribution network, distributed power accessing point closer to the feeder terminal, the voltage rise more, even the upper limit; more power from the distributed power, voltage distribution network node is elevation of greater magnitude, voltage variation is bigger also. Single node access EV, in three modes of electric vehicle fast charging, charging, slow charge, analysis influence of electric vehicle access to the distribution network voltage; multiple nodes access ev. By optimizing the calculation that little part of the node access EV optimal charging power is limited in the fast charge state and the rest of the access node electric vehicle optimal charging power is limited in the filling state, reactive power compensation device of optimal power compensation is less than that of the EV charging power, optimize calculated the optimum electric vehicle charging power and reactive power compensation device optimal power compensation. Electric vehicles in the three modes of slow charge, charge and fast charge, solving the optimal distributed power generation power and reactive power compensation device of optimal power compensation, making each node without power demand have largely been met, each node voltage are in the vicinity of reference voltage fluctuations and improve the distribution network voltage stability and voltage quality. The maximum reduction of the reactive power flow in the grid, the loss of the power distribution system is greatly reduced.