For the safety of the supply, diesel generator (DG) sets are used in various stand-alone power systems using variable-speed generators. The stand-alone hybrid grid system presented in this article, with a wind generator and a diesel generator, but also the system of a ship’s network, serves as an example. To ensure the safety of the ship’s exploitation, the parallel operation of two stand-alone power supplies is required. In parallel operation with the required symmetrical active power load (regardless of the load size), the internal combustion engine of the DG set is often underloaded. This leads to deterioration of its technical properties and, consequently, to a negative impact on the environment. This article presents an analysis of the stand-alone hybrid power system of a ship’s grid consisting of a DG with a speed and voltage regulator and a shaft generator of variable speed—a permanent magnet synchronous generator (PMSG). The possibility of controlling the active and reactive power distribution between the DG and shaft generator (SG) was also studied. Control over the mechatronic SG–DG system limits the harmful influence of the DG on the environment and, most of all, improves the technical qualities of the engine of the DG system, which is often underloaded. Analytic studies of the system were performed, and simulation results of the mechatronic model are presented.
Greater interdependence and integration among the countries worldwide have resulted in the growth of the world trade and, what follows, marine transportation. In the last few years, despite the world economic stagnation, the number of ships has increased. An increase in the marine transportation means greater air pollution caused by ships, what is of paramount importance for the port cities. One of the efficient ways of limiting the negative impact of ships lying in ports on the environment is the power supply from the local electricity stations. This will allow for turning marine power generating systems off, what will result in the emission elimination in the ship's mooring time along with the decrease of noise and vibrations. The infrastructure of the port electric installation necessary for the ships' supply has to be designed so as to make the operating of different ship types possible. It is complicated as all over the world ships are equipped with different electric systems. The paper deals with general issues related to common nominal voltages and frequencies for vessels which call in European harbours and their estimated power demands. Additionally, a case study of a ferry vessel, currently undergoing retrofitting for shore connections, is presented and some particulars concerning technical solutions and environmental profits are described.
Currently, the improvement of efficiency in electricity systems is one of the key tasks facing the industry. Due to the energy criterion, the aim of the optimization of mechatronic systems is to reduce an adverse impact of the armature in the synchronous machine and limit losses in supply lines. In recent years, autonomous generating sets with Permanent Magnet Synchronous Generator (PMSG) and ecological LNG engines are more and more often installed in power systemsThe article presents the concept of using a voltage inverter operating in the power source mode in a parallel connection with PMSG for distribution and regulation of active and reactive power * Corresponding author: d.tarnapowicz@am.szczecin.pl E3S Web of Conferences 46, 00016 (2018) https://doi.org/10.1051/e3sconf/20184600016 3 rd International Conference on Energy and Environmental ProtectionThe functional scheme of the mechatronic system of a PMSG and an autonomous inverter (AI), describing in the article, is presented in Figure 1. In this case, the CSAI block is the autonomous inverter control system, and the ARL block represents the active and passive load with various parameters.
Abstract:The decisive source of air pollution emissions in ports is the berthed ships. This is primarily caused by the work of ship's autonomous generator sets. One way of reducing the air pollution emissions in ports is the supply of ships from electricity inland system. The main problem connected with the power connection of ships to the inland network is caused by different values of levels and frequencies of voltages in these networks (in various countries) in relation to different values of levels and frequencies of voltages present in the ship's network. It is also important that the source power can range from a few hundred kW up to several MW. In order to realize a universal "Shore to Ship" system that allows the connection of ships to the electricity inland network, the international standardization is necessary. This article presents the current recommendations, standards and regulations for the design of "Shore to Ship" systems.
One of the methods to improve the efficiency of the ship’s propulsion is the increase of efficiency in ship generators by using permanent magnet synchronous generators (PMSG – Permanent Magnet Synchronous Generator). Due to the lack of voltage regulator in PMSG, it is necessary to use power electronic converters to maintain a constant voltage level. One of the modes of operation for a ship’s power plant is a parallel work of generating sets. In the parallel work, there are problems in the fluctuation of active and reactive electrical power between generators. The article presents the concept of using inverters in the IHBI topology, which enables the parallel operation of generating sets with PMSG generators. This solution enables the adjustment of the flow of active and reactive powers between generating sets.
The article presents the design of the upper limb joints of an anthropometric dummy intended for rear crash tests for low impact speeds. These joints represent the connection of the hand to the forearm, the forearm to the arm, and the arm to the shoulder. The designed joint is adapted to the construction of a dummy representing the 50th percentile male. The joints currently used on Hybrid III dummies require calibration after each crash test. The construction of the new joint ensures the appropriate strength of individual joint elements and the repeatable value of the joint characteristics without the need for frequent calibrations. The designed joints have the ability to set a variable stiffness characteristic, thanks to which it is possible to use this joint universally in dummies representing populations of other percentile sizes. The range of movement of the joints has been selected to reflect the range of mobility of the upper limb of an adult. The characteristics of the joints were compared with those used in the joints of the Hybrid III 50 percentile male dummy. Moreover, it should be noted that the constructed joints of the upper limb are made by hand; therefore, their comparison with the Hybrid III dummy shows some deviations in the moments of resistance. Making the joints with a 3D printer, taking into account the appropriate material, will ensure greater accuracy and will also result in joining the individual elements of the joint into a whole. The obtained results show slight differences between the moment of resistance in the joints of the constructed anthropometric dummy compared to the hybrid III dummy.
The aim of this study was to compare and evaluate the production of exhaust emissions from a vehicle with a petrol engine with the Euro 4 emission standard and powered by petrol and LPG (liquefied petroleum gas). The paper presents new possibilities for monitoring exhaust emissions using an exhaust gas analyzer. At the same time, it points out the topicality and significance of the issue in the monitored area. It examines the impact of a change in fuel on emissions. This change is monitored in various areas of vehicle operation. Measurements were performed during real operation, which means that the results are fully usable and applicable in practice. The driving simulation as well as the test conditions correspond to the RDE (Real Driving Emissions) test standard. A commercially available car was first selected to perform the tests, which was first measured in the original configuration (petrol drive). Based on real-time RDE driving tests, it is possible to determine the number of exhaust emissions. Subsequently, the same measurements were performed with the same vehicle, but the vehicle’s propulsion was changed to LPG. The vehicle was equipped with an additional system that allowed the vehicle to be powered by LPG. The results from the individual driving tests allowed the determination of the exhaust emissions. Emissions of CO (carbon monoxide), CO2 (carbon dioxide), HC (hydrocarbons), and NOX (nitrogenoxides) were monitored as a matter of priority. Through the driving tests, it was found that the gasoline combustion produced higher CO (1.926 g/km) and CO2 (217.693 g/km) emissions compared to the combustion of liquefied gas, where the concentration of the CO emissions was 1.892 g/km and that of the CO2 emissions was 213.966 g/km. In contrast, the HC (0.00397 g/km) and NOX (0.03107 g/km) emissions were lower when petrol was burned. During LPG combustion, the HC emissions reached 0.00430 g/km, and the NOX emissions reached 0.05134 g/km. At the end of the research, the authors compared the emissions determined by real driving (in g/km) with the emission values produced by the emission standard EURO 4 and the certificate of conformity (COC). Practical measurements showed that the vehicle produced excessive amounts of CO when burning gasoline. This production is 0.926 g/km higher and 0.892 g/km higher when burning LPG compared to the limit set by the Euro 4 Emission Standard. The difference is even greater than the limit value stated in the COC document. For other substances, the monitored values are in the norm and are even far below the permitted value
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