Integrated Filter Inductance Technology And The Applied Research On Locomotive Traction Drive System

As the development of electronics locomotive technology,the traditional DC drive locomotives are gradually replaced by AC drive electric locomotives.The switching frequency of power switching devices become higher,the high harmonic problems which is generated by the AC traction drive system in AC locomotives cause resonance of locomotives-grid,destroy electrical equipment,affect communication lines,etc.Therefore,the study of AC drive electric locomotive high harmonic suppression measures has important engineering practical significance.To achieve the goal of suppression,the paper has finished the following work:1)The paper give the description of each part of the AC traction drive system in detailed,and analyze four-quadrant rectifier’s transient direct current control method and traction inverter’s space vector pulse-width modulation control method.The analysis of AC traction drive system harmonic generation mechanism is taken in the mathematical point.The simulation models established in Matlab analysis the harmonic characteristics,and research the relationship among the harmonic characteristics,locomotive condition,output power and network voltage.2)Study current measures to suppress the high harmonic current and compare their advantages with disadvantages.The paper introduces the principle of integrated magnetic technology and analytical methods.Based on these methods,it proposes the integrated filtering inductance technology using in traction transformer for locomotive traction drive system.A couple of filtering windings as a inductance series a capacitance to suppress the high harmonic current.When established the mathematic model of integrated filtering inductance transformer’s traction drive system(hereafter referred to as new traction drive system),the amplitude-frequency characteristics of its transfer function are analyzed,and the parameter constraints are proposed to make sure suppression effects.3)Based on the practical traction transformer structural parameters,in order to solve the difficult of calculation method of complex short-circuit impedance(important parameters),it proposes the new method of reduced-order inductance matrix method to calculate.Depending on the position of the filter winding arrangement,combined with filtering constraints,the variation range of composited short-circuit impedance and filtering capacitance can be taken.In new traction drive system simulation model established in Matlab,taken equivalent disturbing current as the criterion,the results can prove the feasibility,and give the best allocation with the complex short-circuit impedance and filtering capacitance.