Calculation Of Static Voltage Stability Power Margin Based On Dynamic Continuation Power Flow And Improved Optimization Algorithm On Simulating The Fisher’ Fishing

In the condition of electricity market, the maximum of benefit makes most ofpower system operate in its limiting, state which has made the voltage stabilityproblem in grid prominent. Static voltage stability margin is a type of margin which isused to measure voltage stability of power system. How to find optimal controlvariables to make power system perform in a maximum voltage stability margin hasan important effect for steady performance of power system，which can providereference for operation dispatchers.In the calculation of static voltage stability margin, continuation power flow(CPF) can effectively overcome system close to the voltage collapse point of Jacobimatrix singular problem, which has been widely used. But the continuation powerflow method does not take into account the frequency shift caused by unbalancedpower, it does not consider the imbalance of power by the generators having theability to regulate the problem of sharing. To solve the deficiencies, the method fordynamic continuation power flow is introduced to the classic continuation power flowmethod, establishing the model of dynamic continuation power flow. The dynamiccontinuation power flow (DCPF) is used to calculate static voltage margin of eachgroup control variable. That is to say, the amount of active power imbalance is sharedby the coefficient of power frequency static characteristics and rotary inertia ofgenerator. The introduction of penalty function method is to solve the out-of-limitedproblem of state variables. The paper adds the state variables on objective function inthe form of penalty term, thus a new mathematical model of static voltage stabilitymargin without state variables inequality constraints is built.Different combinations of control variables have a certain influence on thevoltage stability margin. How to adjust control variables to calculate the maximumstatic voltage stability margin is a nonlinear programming problem. Based on the comprehensive analysis of advantages and disadvantages of several intelligencealgorithms, an optimization algorithm on simulating the fisher’fishing (SFOA)algorithm is used to calculate static voltage stability margin in this paper. Consideringthe defects of basic optimization algorithm on simulating the fisher’fishing, to solvethe local optimum in the optimization process by using the accelerate escapemechanisms, the paper puts forward an improved optimization algorithm onsimulating the fisher’fishing (ISFOA) and uses an algorithm which combinesdynamic continuation power flow and improved optimization algorithm on simulatingthe fisher’fishing (ISFOA) to calculate static voltage stability margin. The algorithmtakes each group of control variables as a fisherman’s location, each group of controlvariables corresponding static voltage stability margin as the density of fish of eachfisherman location; uses dynamic continuation power flow to calculate the density offish of each fisherman location; improved optimization algorithm on simulating thefisher’fishing (ISFOA) is applied to search the optimal combination of controlvariables, then calculates the maximum static voltage stability margin. Finally, casesstudy demonstrated the validity and superiority of method and the integrated modelproposed in this paper through the standard node system of IEEE-6and IEEE-30.