Przemysław Szulim

Research Study of the Micro Cogeneration System with Automatic Loading Unit

This article presents the test bench research of a micro cogeneration system with the Stirling engine with an automatic loading system. The tests were conducted for nitrogen as a working gas. The work presents the influence of the load current on the change of the working gas pressure in the working chamber and on the changing voltage on the electric machine. A significant number of repetitions allowed for a statistical rendering of the research description with the use of such measures as: kurtosis, coefficient of variation, coefficient of asymmetry, and of the function of the probability density. The research allows for determining whether the conducted experiment is reproducible and how the chosen parameters influence the character of the system’s work.

Research on a Micro Cogeneration System with an Automatic Load-Applying Entity

The article concerns the testbed research of a micro cogeneration system based on a Stirling engine equipped with an automatic load-applying system. The article presents the influence that the load current has on acceleration of vibration of a micro cogeneration system’s body. The research was conducted while using nitrogen as the working gas. Significant number of tests offered the possibility of providing the description of the results in statistical terms while using such measures as kurtosis, coefficient of variation, the asymmetry coefficient as well as the probability density function. The research offers the possibility of concluding whether the completed experiment is repeatable as well as for determining the impact that selected load changes have on acceleration of the micro cogeneration system’s vibration.

Experimental Research of Electrochemical Energy Storage

The paper presents experimental research involving VRLA (Valve Regulated Lead Acid) AGM (Absorbed Glass Mat) batteries. Test-bench research was conducted in the conditions of constant load current. The paper presents the temperature increase on the battery’s terminals and body accompanying battery discharge in the conditions of a preset ambient temperature. The paper also presents the influence that various discharge current values had on growth of the temperature recorded on the battery’s terminals as well as the change of voltage on the battery’s terminals. Furthermore, the paper includes examination of the influence that changes of ambient temperature have on change of a battery’s useful capacity. The influence of the changes of ambient temperature was examined in a climatic chamber. Change of the battery’s internal resistance and the electromotive force, depending on the level of battery charging, are also presented. The analyses were conducted for a typical operating range of a electrochemical battery.

Experimental Research and Simulation Model of Electrochemical Energy Stores

The first part of the paper presents the results of experimental research involving VRLA (Valve Regulated Lead Acid) AGM (Absorbed Glass Mat) batteries, the lithium-ion batteries and lithium iron phosphate (LiFePO4) batteries. The experimental research was conducted in a static cycle (with constant load current). The paper presents the temperature increase on the battery’s terminals and body. The influence that various values of discharge current have on growth of temperature and change of voltage on the battery’s terminals is also presented. The second part of the paper contains the analytical relations which have been used for building the simulation model in the MATLAB&Simulink environment. The results obtained on the basis of the model have been validated against the results of experimental research.

Online Monitoring of Steel Constructions Using Passive Methods

In the chapter the possibilities of development of distributed diagnostic system capable of online structural health monitoring of civil engineering structures are discussed. Instead of commonly used methods of determining the technical state of the construction that are usually focused on searching for cracks, material heterogeneities and assessing concrete or steel degradation, the methods proposed for the system are based on the comparative strain gauge, acceleration and passive magnetic measurements. All this measurement methods are used for stress assessment in critical fragments that are vital for stability and durability of the structure. Evolution of defects in the construction causes measurable changes of stress distribution in critical joints of the construction. Additionally, materials that could cause threat of the catastrophic accident caused by fatigue wear, exceeding stress limits or emerging of plastic deformations have magnetic properties that could affect the local magnetic field. Stress limits could be then constantly supervised taking into account the range of permanent and elastic deformation, which would allow for early detection of threats. SHM data analysis is taking into consideration a series of magneto-mechanical and other phenomena occurring during the construction/machine’s operation and also actual magnetization conditions of the object examined in exterior magnetic field (Earth’s or derived from adjacent elements).

Analysis of Vibration of Rotors in Unmanned Aircraft

In the paper, solution of the problem of vibrations which appears during the maneuvers of quadrocopters is presented. Those special kinds of vibration aren’t related to mounting or manufacturing faults. In this kinds of flying machines the main sources of vibration comes from motors and/or propellers unbalance. The paper shows analytical description of the source of this problem. Mathematical description of rotor which was subjected of additional rotation had been modeled in MATLAB/Simulink environment. It was shown, that correct set of parameters lead to total elimination of this kind of vibration.

Application of Vision Based Damage Detection for Real Civil Engineering Structure

Structural Health Monitoring (SHM) is an emerging field of technology that involves the integration of sensors, data transmission, processing and analysis for detection, as well as localization and assessment of damage which can lead to its failure in the future [1,. In general, SHM methods can be divided into two groups: local and global ones. The second group can be applied if a global change in the geometry of a structure can be observed. In practice, the most commonly used methods of damage detection are based on the analysis of variations in various dynamic properties caused by damage [3,. However, the excitation of large structures can be costly and difficult. The acquisition of static deflection requires much less effort, which makes the damage detection methods based on changes in deflection curves more attractive for practical use [5-1. Damage detection and localization methods require a densely sampled deflection curve.

Experimental Evaluation of Mathematical and Artificial Neural Network Modeling of Energy Storage System

This article presents an experimental evaluation based on a mathematical model and an artificial neural network (ANN) model of an energy storage system. Because of a nonlinear description of charging/discharging dynamics in subsequent cycles and a coupling of the terminal voltage and temperatures of a battery, the recurrent artificial neural network structure (R-ANN) is proposed. Both models, analytical and R-ANN were employed to predict a behavior of the VRLA AGM battery. A training and testing data were gathered at the laboratory stand in different working conditions. As a result, we present the analysis of differences between proposed modeling approaches.

Autonomous Agricultural Robot – Testing of the Vision System for Plants/Weed Classification

The aim of the paper was to present results of the vision system for plants/weeds classification testing of autonomous robot for sowing and wide row planting. Autonomous work of the robot in range of traction and agronomic processes will be implemented on the basis of data from a many sensors (cameras, position and distance). Positive test results will allow for the use of the robot in organic crops requiring mechanical removal of weeds or in crops with application of selective liquid agrochemicals limited to the minimum. Unless the control systems are improved and development costs are compensated, the production of autonomous agricultural systems will increase. So that very important is mentioned in this paper, vision system of plant/weed classification. The vision system for sugar beet/weed and sweet corn/weed classification was build and tested. The position of each plant must be determined for intra-row weeding. This means that plants have to be classified into two classes, i.e., sugar beet (sweet corn) or weed.

Operational Research of VRLA Battery

In the following article research results for VRLA gel battery performance in the dynamic load cycle is presented. The research was conducted for several-hundred consecutive charging/discharging cycles. In the work there are presented changes of usable capacity of the battery and impact on a life-time of the battery in dynamic load conditions. There is also presented the effect of load current value on heat emission process, caused by an increase of temperature values on the battery casing and terminals. Acquired results are compared to operational conditions provided by the manufacturer. The research was conducted on two factory new VRLA batteries, which in the course of the tests were completely worn out.