Research Of Integrate Testing Device For Electrified Railway Based On Labview

With high-speed railway development and due to the long-scale usage of electronic devices, non-linear power electronic devices,Reactive power, harmonic and negative sequence become more and more complex in the traction power supply system. On one hand, these problems not only influence traction power supply system, but also have great impact on the public power; On the other hand, in the test and analysis of the high-speed railway traction power supply system, higher requirements are put forward for power quality by railway departments. Under this background, a new type of the Reaearch of Integrate Testing Device for Electrified Railway is develoed,with the specific work is as follows:Firstly, the existing algorithm of the three-phase power, the single-phase power and the measurement part of harmonic are researched in non-sinusoidal system, discussing the correlation calculation principle and the calculation method. The single-phase power algorithm based on the instantaneous power theory and the harmonic algorithm based on the simulation analysis are simulated respectively. Due to the discussion and analysis of harmonic measurement algorithm, combining with the actual situation, a practical method that is combined with trigonometric function and low pass filter to detect harmonics is presented. In this method, the mixed signal of the desired DC and AC are received, after the detected signal through the cosine multiplier. In the design of low pass filter, a better filtering effect is obtained by using the method combining moving average filter and Butterworth low-pass filter. The method’s advantage is low cost and high efficiency. Calculation reactive power lay the foundation according to the IEEE Std 1459 standard and provide basis for reactive power compensation and the calculation of capacity etc.Secondly, a new type of Rresearch of Integrate Testing Device for Electrified Railway is designed based on Lab VIEW virtual instrument software platform with researching for the algorithm. In software design, the functions of the signal acquisition, the data processing, the data display, the report printing, and the analysis of network pressure, signal in different periods and supply capacity are reached. In addition, above all of these left margins for the expansion of the system software upgrade. In hardware design, the design of circuit and the selection of data acquisition card and current clamp are accomplished.Eventually, the feasibility of the device for the combine of software and hardware is verified after the development of comprehensive test device of electrified railway and the experiment in the field, acquiring the recognition of the field technicians.