The Research Of Following-setting Mode Multitap Arc-suppression Coils Based On Bidirectional Triode Thyristor

With the rapid development of computer control technology and power electronics technology,the research on earthing compensation technique of anti-arc coil has entered a period of rapid development.Although single-phase-to-ground fault,fault location and isolation make breakthrough progress,the structure and control methods based on arc suppression coil ontology technology have not been greatly advanced in recent years.The thyristor-adjuated arc suppression coil based on power electronics technology(high short-circuit impedance suppression coil)is only a flash in the industry because of the serious harmonic pollution.The technology of full current compensation arc suppression coil based on APF is still not mature so far,and costs high.The traditional multitap arc suppression coil is still used by the vast number of users because of its economy and reliability.In this paper,from the practical point of view of the product,existing multitap arc suppression coil product is partial reformed based on mature power electronics technology and a new following-setting mode-multitap arc suppression coil device is designed.Firstly,the principle of resonance grounding of arc suppression coil is briefly introduced.The working principle and design principle of the traditional multitap arc-suppression coil are discussed emphatically.On this basis,the technical scheme of following-setting mode-multitap arc suppression coil with bidirectional triode thyristor is proposed.The scheme adopts a bidirectional triode thyristor instead of the original load switch,realizing the upgrade from the "presetting" to "following-setting ".This paper introduces the working principle of the main topology circuit and the specific technical implementation of the control circuit with following-setting mode-multitap arc suppression coil in detail.In this paper,8 turns arc suppression coil controlled by 7 groups of bidirectional triode thyristor is designed and implemented,and the selection and design of equipment and devices are completed.Secondly,simulation model of following-setting mode-multitap arc suppression coil is built,which based on actual device type XHDCZ-300/10.5/15-50 arc suppression coil parameters.Then its turn regulation function and characteristics of following-setting are verified,the working voltage and current stress of bidirectional triode thyristor aresimulated and evaluated.The simulation results show that the device can meet the arc suppression coil turns and with the following-setting function,achieve the pre-design goals.Finally,this paper makes a discussion on the transient problem caused by rapid switch of bidirectional triode thyristor in the end and establishes a mathematical model of transient circuit,which gives a mathematical analysis of the transient process of fast switching.The solution to the problems caused by fault transient and fast switching is given.