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The article is devoted to the studying the processes of establishing oscillations in the generator on backward wave. The superregenerative mode has been considered within the framework of the linear theory. In the analysis, a complex frequency is introduced, the imaginary part of which characterizes the increase in oscillations over time. One of the main peculiarities of considered two-dimensional model is accounting focusing magnetic field effect. In the presence of longitudinal magnetic field of finite magnitude the transverse high frequency displacements in electron beam occur in addition to the longitudinal ones. The method of successive approximations has been used in analysis. The case of cyclotron resonance is considered separately, when only a slow cyclotron wave is excited in the electron beam, which noticeably simplifies the original problem and the initial relations.

Hybrid vehicles are widely used in many cities because of their lower rates of fuel consumption and for environmental initiatives. This paper presents the fuel consumption rate analysis of multiple parallel and series drive train type hybrid buses operating in the City of Edmonton, Alberta, Canada, on different urban routes. Based on an analysis of real time daily bus data, the optimal choice between the different types of hybrid buses for Edmonton Transit System (ETS) urban routes is presented and discussed.

This paper presents analysis of a proposed series hybrid configuration suitable for use in a transit bus. A model of an existing vehicle drivetrain is validated against experimental data collected over an eight month period. Modeling the vehicle with a flywheel energy storage system, a corresponding control scheme for the generator is proposed. Based on the recorded driving conditions, a series of simulations are conducted to verify the feasibility and performance of the proposed design. Based on the simulation results, an economic comparison between the proposed and original design is provided demonstrating the economic advantage of the proposed design.

Computer loads can be found in all of society's industrial, commercial and residential sectors. The nature of these loads is such that they distort the line current waveforms and in some cases can significantly distort the supply voltage waveforms causing disruption in computer system performance. This paper presents several case studies to reveal the unique power quality characteristics of an individual computer and the nonlinear aggregate characteristics of multiple computers being serviced from a point of common coupling. A new modelling methodology is presented which can be used to model the power quality characteristics of single and multiple connected computer systems and to assess the impact of voltage and current waveform distortions on computerized processes and electrical power systems.

Voltage sags, also known as dips, are increasingly important to industrial reliability. Modern process controls are often sensitive to voltage sags. The combination of a voltage sag and sensitive equipment may cause significant production outages. Less sensitive equipment may be available at a premium price, but the designer must know the sag characteristics of the electric system to make the best choices between reliability and cost. This proposed chapter offers a way to predict voltage sag performance without long term monitoring and before plants are constructed. The analysis technique proposed for a new chapter 9 in the next revision of IEEE std 493 is shown. >

The operation of a family of harmonic correction networks for 3 phase diode rectifiers is described that use a combination of thyristor and IGBT switches. Four distinct networks are described that provide a variety of current waveshaping techniques. Variations of these networks either lower the size of the line inductors required or use very low switching frequencies. The IGBT switches are used for thyristor commutation and an improved current waveshaping function. The thyristors are used to select the appropriate phase of the AC supply to inject current pulses. The resultant harmonic correction networks are low cost and have very low per unit current ratings. The resultant complete rectifier topology can be operated with a very low harmonic distortion in the AC supply current. Design parameters are given in per unit to illustrate the very low device per unit current ratings.

A noniterative method for solving load flow equations is presented in this paper. The method is based on the Taylor series expansion of the inverse load flow function. Formulas to compute the Taylor series are derived and associated solution algorithms are developed. Load flow results can be obtained by simply calculating and summing the significant terms of the series.

The PWM asymmetrical half-bridge is used to control the output current of a three-phase diode rectifier with a capacitor smoothed output voltage. The controlled-current function provided by the bridge improves the performance of the rectifier by lowering the low frequency ripple in the diode rectifier output current and by maintaining a balanced AC supply current when the AC supply voltage is unbalanced. The two-switch asymmetrical bridge can be designed with low per-unit voltage ratings, typically 15%, and can guarantee equal current sharing between parallel rectifiers. The higher conduction losses introduced by the bridge is offset by the improved diode rectifier performance, the low voltage devices used in the bridge, and the use of smaller L-C filter components. Balanced UPF sinusoidal supply currents can be obtained by using a three-phase bi-directional Y-switch and two asymmetrical half-bridges to separately control the output currents at both the diode rectifier output terminals. The asymmetrical bridge switches are exposed to only half the rectifier output voltage and the three-phase Y-switch has very low rms per-unit current ratings.