Research On Short-circuit Dynamic Stability Check Of Bus Bars

Power system dynamic stability check is one of the safety check that the engineering designers have to do when choosing all kinds of high and low voltage equipment as well as the conductor.In the power system bus plays an important role of collection and distribution of electric energy,the bus short-circuit dynamic stability verification is to verify the dynamic stability when short circuit occurred,the accuracy of the calibration results directly affects the safe and stable operation of the system.The main basis of the traditional short-circuit bus dynamic stability check is related to the design of the conductor in the electric power engineering electrical design manual.The main concern is the dynamic stability check of the supported bus at the high voltage level.With the development of power system,the high voltage line equipment dynamic stability to meet the requirements of the premise,to ensure low voltage equipment dynamic stability become more and more important.Although it can meet the needs of engineering design,the accuracy of the research is to be discussed.In order to meet the requirements of the calculation accuracy of bus short circuit stability under different voltage levels and support methods,this paper is based on the general procedure of short circuit stability check of power system.First,the maximum short-circuit current conditions and amplitude were theoretical derivation,discussed different voltage levels under short-circuit current peak conditions and impact factors of value,and design manual related results is compared.Then,the mathematical expression of the tube type bus short circuit electric power calculation is derived.Using genetic algorithm to calculate the conditions of the extreme value and the extreme value of the different voltage levels,and compared with the calculation method of short circuit in the design manual.The response of the bus bar with different vibration frequencies to short circuit is discussed,and the influence of the vibration coefficient on the calculation results of the electric power is analyzed.Finally,the modal characteristics of the suspended tubular bus and V insulator are simulated and analyzed by using ANSYS finite element software.The relationship between the vibration frequency and the stiffness of the insulator is studied.Calculation and simulation results show that in the low voltage level of the power system,the short circuit impact coefficient slightly higher than design manual and peak current time than manual's 0.01s;maximum short-circuit power time in low voltage level system earlier than manual's 0.01 s,at this time at the beginning of the current phase angle is large than 5?/12,the amplitude of the electrical force slightly higher than the manual's calculation results.In the calibration,the response of the natural frequency of the bus to the electric power is considered,and the calculation method of the manual is relatively safe and conservative to the action of the suspension tube bus.