A study on results of TPS according to the optimum traction power supply system of Urban MAGLEV railway No . 66
The main purpose of this study is to conduct correlation factor analysis in both headway time and power capacity by means of analytical approach to results of power property in terms of headway time of Urban MAGLEV from the standpoint of headway time of Urban MAGLEV on the Incheon international airport maglev railway, in the process of construction at the moment, in Korea. Railroad track, as a fundamental condition of service simulation, is set up with double track, and it is therefore that the three patterns of headway time of Urban MAGLEV on the track. TPS is performed by Urban MAGLEV operation consisted of three separated patterns in headway time on the double railroad track or the trial track. As a result of such simulation, three types of characteristics listed below were obtained. 1) The peak power capacity related to transportation demand on the trial track compared to the result given. 2) The optimum capacity of substation is determined based on the analysis. 3) The location of substations is determined based on the analysis. The result of research performance, therefore, enables us to reflect the power supply system design for the stabilized and economized Urban MAGLEV operation
Analysis of dynamic load behavior for electrified mass rapid transit systems
This paper investigates the dynamic load flow behavior of an electrified mass rapid transit (MRT) system. Because the power consumption of an MRT system varies with train operation mode and system route gradient, curvature, etc., the motion equation of train sets has been applied to find the mechanical power required for train operation. The electrical input power to the car borne VVVF inverters for the driving of induction motors are solved by the simulation of power electronics. The impedance matrix of the DC power network is then modified for each study snapshot based on the train location and the corresponding resistance change of the conducting 3rd rail and train running rail. The DC and AC load flow analyses have been performed for a practical MRT line in Taipei by considering the operation timetable and actual ridership to demonstrate the effectiveness of the proposed computer simulation methodology. The power consumption of the MRT is solved and the energy conservation by electric regenerative braking when the train set approaches the next station is also determined. The variation of traction transformer loading factors with train operation are calculated for the evaluation of power system operation efficiency. It is concluded that the power flow analysis does provide a very useful tool for the proper capacity planning of traction substations during the design stage of an MRT system.
Slotted Waveguide Antenna With Two Radiation Nulls
A design of a linear array antenna having two radiation nulls and otherwise omnidirectional radiation pattern is reported. A new configuration of a waveguide broad wall longitudinal slot doublet with positive and negative offsets with respect to the waveguide center line is used to design the array. This type of doublet produces two radiation nulls. Each of the null directions can be shifted at least up to plusmn25deg by proper choice of slot offset. Resonance and radiation characteristics of the proposed doublet are also presented. Finally, one linear array antenna consisting of seven doublets has been fabricated. Measurements show that the 15 dB null widths are 14.2deg and the null depths are at least 24.8 dB. Maximum gain ripple in the omnidirectional region is 1.75 dB.