Jan Leuchter

Dynamic Behavior Modeling and Verification of Advanced Electrical-Generator Set Concept

Current development trends regarding mobile electrical-generator sets (EGSs) indicate that enhancement of efficiency is to be sought in means to operate the driving engine (either diesel or gasoline) continuously at its optimum speed. The engine-generator dynamics at a sudden load change (from low load to high load) remains a challenge in this regard. The dynamic behavior analysis presented here proves that the introduction of an energy storage element into the EGS with variable-engine-speed concept eliminates this drawback. This paper addresses the identification of the dynamic behavior of such variable-speed EGS systems and the problems encountered during a sudden increase of load (power and voltage drops).

Bi-directional DC-DC converters for supercapacitor based energy buffer for electrical gen-sets

The real drawback of the concept of electrical generator sets (EGS) with variable speed is the engine-generator dynamics at sudden load change from low to high. The analysis of dynamic behavior presented in this paper proves that the disadvantageous dynamical properties of EGS concepts with variable speed of engine can be improved by using an energy storage element. This paper give results of design of the bi-directional DC-DC converters for energy buffer with supercapacitors and also demonstrates the results of dynamic behavior EGS with energy buffer.

Dynamic Behavior of Mobile Generator Set with Variable Speed and Diesel Engine

The engine-generator dynamics at a sudden load change (from low load to high load) remains a challenge in case of variable speed diesel generator. The dynamic behavior analysis presented here proves that the introduction of an energy storage element into the EGS with variable-engine-speed concept eliminates this drawback. This paper addresses the identification of the dynamic behaviour of such variable-speed EGS systems and the problems encountered during a sudden increase of load (power and voltage drops).

High-speed generator — Converter set for auxiliary power units

Common and significant features of power source for auxiliary power unit with variable highspeed generator-converter set are shown in this paper. Power electronics is one of the fastest developing technologies and this paper introduces the basic concepts in power conversion systems with highspeed generator. Main feature of these generators is surveyed too. Three different configurations of power converter are considered. The natural question arises: Does the high-speed concept change anything in the investigation? The efficiency of the overall system is here investigated and an optimal topology is discussed. Because switching of power electronics is a source of EMI, therefore, in this paper the attention is briefly focused also on electromagnetic interface.

Review of power electronic concepts of hybrid power source

In this paper, power supply unit based on the Engine-Generator Set (EGS) will be discussed. The recent trends lead to the use of more autonomous power sources to satisfy the maximum energy yield. These power units can be considered as comparatively sophisticated system, consisting of mechanical part, electromechanical energy conversion part, power electronics and control (feed-back) part. These systems usually request a power buffer with battery and bi-directional dc-dc converter. Two aspects will be considered, namely power electronics converter concept with central boost converter design. This paper also briefly shows experimental verification of these modern power sources.

Investigation and measurement of aircraft communication system immunity

This paper considers immunity of a military airborne communication system against low and high power interfering signals in accordance with standards for aeronautical radio stations operating in VHF band 117.975-136.975 MHz and UHF band 225-400 MHz. Our intention here is to highlight test procedures of certain receiver parameters mainly according to the standards: RTCA DO-186A; and MIL-STD-188-243. Receiver immunity against undesired reception channels is given by its frequency response which is determined by the receiver selectivity and spurious response rejection. We are contemplating issues of interference and immunity of an aircraft communication system against high-power signals originating in power electronic circuits of aircraft power systems. This paper presents measurements of the AM receiver selectivity, spurious response rejection, intermodulation response rejection, desensitization as well as the EMC issue. The proposed automated measurement setup using the graphical language environment VEEPro is shown in this paper.

Investigation of avionics power switch loading versus aircraft electromagnetic compatibility

In this article, we have seen that high-frequency switching of converters can increase the power density and have an effect on efficiency losses and signal harmonics producing EMI.

Mathematical modeling of photovoltaic systems

This paper proposes a mathematical model for photovoltaic panels (PV) in the range 10–25 V with approximately 50 W of power generation and an open-circuit voltage below 25 V. Mathematical models of PV are presented, compared and verified against experimental measurements on a photovoltaic set-up. This shows the advantage of mathematical modeling of photovoltaic panels to achieve maximum power by maximum power point tracking (MPPT), compared with previous methods, since a novel model can be implemented easily in the controller to establish maximum power. A flexible design with high efficiency is thereby achieved.

An interface converter of hybrid power sources with supercapacitors

Hybrid electrical power sources are one of the future trends in the area of power sources. They can be composed of many interacting components such as electrical generator sets with optimum variable speeds or constants speeds, photovoltaic sources with maximum power tracker, wind power generators, fuel cells and batteries. Hybrid electrical power sources initially developed and produced mainly for military purposes, more gradually found their use as power supplies for various machines and appliances to increase their power density. The paper briefly shows suggested solution of power electronics to obtaine high efficiency and good dynamic behavior properties. The dynamic behaviors of these sources are mainly given by diesel engine. Power electronics with battery buffer can help to improve dynamic behaviers. This paper presents a new interface converter with battery buffer.

Dc-Dc converters with FPGA control for photovoltaic system

The paper introduces on operating principle of power management of photovoltaic system with maximum power tracker control to achieve the maximum efficiency of such systems. The paper presents different topologies of basic photovoltaic concepts with DC-DC converters including control design of maximum power tracker by Matlab-Simulink. The paper will be present different topologies of converter concepts that improve the total efficiency value. PWM controlling of such sophisticated system can be achieved by field-programmable-gate-array (FPGA) that more details of set up PWM signals due to FPGA technologies is shown in this paper.