Radovan Dolecek

FOC and flux weakening for traction drive with permanent magnet synchronous motor

This paper analyses control algorithm for permanent magnet synchronous traction motor (traction PMSM) usable for light rail vehicle. The algorithm is based on field oriented control. The field oriented control and carrier based pulse width modulation allow simply implementation of flux weakening control algorithm. The flux weakening provides wider speed operation of traction drive with PMSM. Simulations and experimental results are given. For experiments we have used a special experimental stand with a prototype of tram traction PMSM. Power of the PMSM is 58 kW. Description of the stand is given in the paper too.

Control Algorithms for Permanent Magnet Synchronous Traction Motor

The paper deals with research of sturdy control algorithm for traction drive with permanent magnet synchronous motor (PMSM). Two design algorithms are described here. First algorithm is control of phase currents which are based on control of instantaneous value of current for all phases of motor. Second algorithm is represented by control of phase currents in d-q frame (Field Oriented Control). The algorithms, which are mentioned above, are compared in this paper. Simulations results of both algorithms and partial results from measurement of traction motor with PMSM are cited in this paper, too. The traction motor with nominal power 58 kW makes use of phase currents control.

Computing of bistatic cross-ambiguity function on GPU

The real-time computation of cross ambiguity function (CAF) using brute force and block processing methods is a challenging task for parallel programming techniques. CAF is a key function for successful location tracking by passive radar systems. In this paper, the comparison of CAF methods computation and using a Graphics Processing Unit (GPU) are presented. The main goal of the research is to compare the computation efficiency and speed of the CAF methods on the GPU hardware with a single or multi-Core PC workstation. The results show the highest speed-up factor using GPU for all CAF methods.

Real-time sound source localization

This paper deals speaker localization using received acoustic signals on microphone array. The real time localization system is based on method for a speaker speech processing and extraction of sibilant sequence. It is shown, that this method leads to good position estimation accuracy in indoor systems.

Estimation of Antenna Gain

A simple formula for estimation of gain is verified for the shaped-beam antenna. As an example, experimental results of five Hogg-horn antennas, along with their mean values, are published and compared with the simple approximation of gain. The simple gain approximation could be very valuable for system engineers to accurately estimate antenna gain and perform EMC calculations (estimations of interference and susceptibility).

Dual source railway vehicles

The paper deals with research activities about technical aspects of dual source railway vehicles on the Czech railway traffic system. The thought vehicle uses for powered traction equipment the catenary and traction battery system. The battery system design is based on the traction and vehicular simulations.

Propagation over terrain considering refractivity profiles

The physical optics (PO) calculations have been utilized for numerical simulations of electromagnetic field above irregular ground. The PO approximation and numerical simulations using parabolic equation method are used for new comparison with findings of longstanding testing of microwave field and tropospheric refractivity profiles. It is demonstrated that the PO could offer reliable numerical simulations for low altitude field and diffraction field zone even for numerous three-dimensional distributions of the atmospheric refraction.

Far-field antenna range

The design of completely rebuilt antenna far-field range is described. The results of new measurement campaign are given for various cases. The paper analyzes briefly electromagnetic wave propagation over irregular terrain by physical optics approximation of vector problem using an enhanced analysis. The comparison of numerical simulations and measurements for the new far-field range is given.

Speed-up the computing of bistatic cross-ambiguity function on different hardware configuration

Cross ambiguity function (CAF) is the key function for successful location tracking for passive radar systems. This paper describes several methods of the CAF based on block processing. The computation time of the CAF is a challenging problem for parallel programming techniques. In this paper the CAF is computed with Multi-core and Cluster approaches.

Research of harmonic spectrum of currents in traction drive with PMSM

The paper deals with the significant results of the experimental research of the harmonic spectrum of currents and induced voltages at traction drive with permanent magnet synchronous motors (PMSM). The experiments were done in a special workplace with a real traction drive for wheel vehicles. The harmonic spectrums of currents were analyzed by a specialized device on the basis of a central measuring station. The knowledge of marked subharmonic components of stator winding currents is the most significant finding of these experiments. The frequencies of these components are given by multiples of frequency of mechanical speeds. The subharmonic components also pass to the dc current at an input site of the traction inverter. This fact is particularly important from the viewpoint of legislative requirements to electromagnetic compatibility (EMC) of drive with railway interlocking devices.