Research On Fast Decoupled Load Flow Algorithm Based On Matrix Operation

Electrical energy is crucial and vital for social productivity,which is playing an increasingly essential part in our daily life and social development.Power flow calculation is a basic tool for power system analysis.Based on its different purpose and emphasis,it can be divided into two categories:one is engineering-oriented power flow,the other is research-oriented power flow.Research-oriented power flow does not pursue very fast computing speed,but pays special attention to the clear-cut and terse algorithm program,and is easy to write,correct and add new functions,and it is always used for further evolution of the algorithm.The fast decoupled load flow is supported the simplification and improvement of Newton power flow in polar coordinate system,compared with Newton method,it has faster calculation speed and better convergence.Therefore,this thesis designs the algorithm from two perspectives of circulation and matrix operation,and applies the algorithm into Matlab platform.The main contents are as follows:First of all,this thesis studies the fast decoupled load flow which is based on the circulation.It adopts the adding branch method to design the admittance matrix,coefficient matrix,which the type of branch is determined by scanning each branch first,then the matrix elements are calculated in turn and finally the matrix is formed.Using cyclic structure to calculate node power,branch power,the amount of unbalance and solve linear equations.In the design,by adding appropriate judgment statements to skip unnecessary operations,and according to the data storage characteristics of Matlab,the operation sequence is designed,which saves the calculation time.The fast decoupled load flow algorithm based on cyclic structure has the characteristics of simple principle,clear structure and easy expansion,and also has fast operation speed.Secondly,the fast decoupled load flow that adopted the matrix operation is studied.The admittance matrix,coefficient matrix,node power,branch power and unbalance module are designed by matrix operation and complex operation.The solution of linear equation group uses Matlab solution equation method and triangle decomposition method.Each module has designed a variety of schemes.Using the unique characteristics of Matlab platform,which is good at matrix operation and complex calculation,the fast decomposition power flow algorithm is designed in the form of matrix operation,which simplifies the algorithm and greatly improves the calculation speed.Finally,the algorithm is analyzed by using the data of 445-bus power system of Northeast China Power Grid.The results show that the fast decoupled load flow algorithm used in the two scientific research purposes designed in this thesis has correct calculation results,faster calculation speed,can meet the requirements of scientific power flow algorithm,and has strong practical value.