Study On Capacity Ratio Of Wind-thermal-bundled Power Transmitted By AC/DC System Under Transient Stability Constraints

At present,the installed capacity of wind power and thermal power in Inner Mongolia ranks first in China,and in order to solve poor power problem in Inner Mongolia,Three UHV AC and UHV DC transmission lines have been planned.As a result,wind-thermalbundled power transmitted by AC/DC system methods have become an important way for Inner Mongolia's electric power transmission.In this mode of operation,the capacity ratio of wind power and thermal power output has an important influence on the stable operation of the system,especially the transient stability of the system.Therefore,in order to ensure the stable operation of the wind-thermal-bundled power transmitted by AC/DC system,it is necessary to analyze the influence of the capacity ratio of the wind-thermal output on the transient stability of the system,and to find out the ratio of the wind-thermal output capacity when the transient stability of the system is optimal..Firstly,this paper introduces the numerical solution and direct methods for transient stability analysis of power systems,and introduces the specific steps,implementation methods,and algorithm features of the two algorithms.Secondly,the mathematical models of synchronous generators,doubly-fed induction generators and HVDC transmission systems are studied,and a model of wind-thermal-bundled power transmitted by AC/DC system is built.Thirdly,the method of transient stability analysis for wind-thermal-bundled power transmitted by AC/DC system is studied based on the Extended Equal Area Criteria,simplified processing of the system and analysis of the rotor motion characteristics before and after the wind power system,based on the transient stability criterion,the ratio of output capacity of wind power and thermal power has effect on the transient stability of the system is analyzed,in the MATLAB simulation platform to build a hybrid system simulation model,combined with a simulation example to verify the accuracy of the theoretical analysis.Finally,this paper gives the wind power and thermal power capacity ratio objective function and constraints,and designs the adaptive genetic algorithm for wind power and thermal power capacity allocation of Wind-thermal-bundled Power Transmitted by AC/DC System,the convergence and search capabilities of the algorithm were analyzed with the example.The domain simulation method verifies the correctness of the genetic algorithm results.