Evolution engine technology in exhaust gas recirculation for heavy-duty diesel engine

In this present year, engineers have been researching and inventing to get the optimum of less emission in every vehicle for a better environmental friendly. Diesel engines are known reusing of the exhaust gas in order to reduce the exhaust emissions such as NOx that contribute high factors in the pollution. In this paper, we have conducted a study that EGR instalment in the vehicle can be good as it helps to prevent highly amount of toxic gas formation, which NOx level can be lowered. But applying the EGR it can lead to more cooling and more space which will affect in terms of the costing. Throughout the research, fuelling in the engine affects the EGR producing less emission. Other than that, it contributes to the less of performance efficiency when vehicle load is less

Grid-connection approaches for pico-hydro systems

Small hydropower systems are considered an environmentally friendly energy option. They have a huge untapped potential which allow it to make a more significant contribution to future energy demand with many advantages. Grid-connected pico-hydro systems are an emerging solution for application in a huge number of applications such as in household water supply, wastewater treatment facilities and to improve control systems and optimize generation as a part of integrated water management systems. They are also very promising for integration in microgrids in many developing countries. This paper presents and discusses the main three grid-connection approaches for pico-hydro systems: using specifically designed power converters; using standard wind inverters; and using standard photovoltaic inverters. These latest approaches based on conventional inverters are practical solutions able to explore a large amount of feasible sites with low-head and very low-head. Moreover, photovoltaic micro inverters, recently launched in the market, are propose for very low power generators (250-300 W). These approaches improve efficiencies, reduce costs and environmental impacts and improve reliability. Experimental evaluation of the performance in steady-state and in dynamic conditions proves the feasibility of these innovative approaches.info:eu-repo/semantics/publishedVersio

Reliability-based design with system reliability and design improvement

This thesis focuses on developing a methodology for accurately estimating series system probability of failure. Existing methods for series system based design optimization are not that accurate because they assign reliability to each failure mode; as a result complete system reliability goes down. According to method proposed in this work, the user will assign required system reliability at the start and then optimizer will apportion reliability to every failure mode in order to meet required system reliability level. Detlevson second order upper bounds are used to estimate system probability of failure. Several examples have been shown to verify the results obtained --Abstract, page iii

Silicon Photonic IQ Modulators for 400 Gb/s and beyond

Silicon photonics has enormous potential for ultrahigh-capacity coherent optical transceivers. We demonstrate an IQ modulator using silicon photonic traveling-wave modulators optimized for higher-order quadrature amplitude modulation (QAM). Its optical and RF characteristics are studied thoroughly in simulation and experiment. We propose a system-orientated approach to optimization of the silicon photonic IQ modulator, which minimizes modulator-induced power penalty in a QAM transmission link. We examine the trade-off between modulation efficiency and bandwidth for the optimal combination of modulator length and bias voltage to maximize the clear distance between adjacent constellation points. This optimum depends on baud rate and modulation format, as well as achievable driving voltage swing. Measured results confirm our prediction using the proposed methodology. Without pre-compensating bandwidth limitation of the modulator, net data rates up to 232 Gb/s (70 Gbaud 16-QAM) on single polarization are captured, indicating great potential for 400+ Gb/s dual-polarization transmission

Particle Swarm Optimization-Based Control for Maximum Power Point Tracking Implemented in a Real Time Photovoltaic System

Photovoltaic panels present an economical and environmentally friendly renewable energy solution, with advantages such as emission-free operation, low maintenance, and noiseless performance. However, their nonlinear power-voltage curves necessitate efficient operation at the Maximum Power Point (MPP). Various techniques, including Hill Climb algorithms, are commonly employed in the industry due to their simplicity and ease of implementation. Nonetheless, intelligent approaches like Particle Swarm Optimization (PSO) offer enhanced accuracy in tracking efficiency with reduced oscillations. The PSO algorithm, inspired by collective intelligence and animal swarm behavior, stands out as a promising solution due to its efficiency and ease of integration, relying only on standard current and voltage sensors commonly found in these systems, not like most intelligent techniques, which require additional modeling or sensoring, significantly increasing the cost of the installation. The primary contribution of this study lies in the implementation and validation of an advanced control system based on the PSO algorithm for real-time Maximum Power Point Tracking (MPPT) in a commercial photovoltaic system to assess its viability by testing it against the industry-standard controller, Perturbation and Observation (P&O), to highlight its advantages and limitations. Through rigorous experiments and comparisons with other methods, the proposed PSO-based control system’s performance and feasibility have been thoroughly evaluated. A sensitivity analysis of the algorithm’s search dynamics parameters has been conducted to identify the most effective combination for optimal real-time tracking. Notably, experimental comparisons with the P&O algorithm have revealed the PSO algorithm’s remarkable ability to significantly reduce settling time up to threefold under similar conditions, resulting in a substantial decrease in energy losses during transient states from 31.96% with P&O to 9.72% with PSO

New Trends in the Control of Grid-Connected Photovoltaic Systems for the Provision of Ancillary Services

Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).The gradual displacement of conventional generation from the energy mix to give way to renewable energy sources represents a paradigm shift in the operation of future power systems: on the one hand, renewable technologies are, in general, volatile and difficult to predict; and on the other hand, they are usually connected to the grid through electronic power converters. This decoupling due to power converters means that renewable generators lack the natural response that conventional generation has to the imbalances between demand and generation that occur during the regular operation of power systems. Renewable generators must, therefore, provide a series of complementary services for the correct operation of power systems in addition to producing the necessary amount of energy. This paper presents an overview of existing methods in the literature that allow photovoltaic generators to participate in the provision of ancillary services, focusing on solutions based on power curtailment by modifying the traditional maximum power point tracking algorithm

Maximum power point tracking (MPPT) control of pressure retarded osmosis (PRO) salinity power plant : development and comparison of different techniques

This paper presents two new methods for the maximum power point tracking (MPPT) control of a pressure retarded osmosis (PRO) salinity power plant, including mass feedback control (MFC) and fuzzy logic control (FLC). First, a brief overview of perturb & observe (P&O) and incremental mass resistance (IMR) control is given as those two methods have already demonstrated their merit in good control performance. Then, two new methods employing variable-step strategy, MFC and FLC, are proposed to address the trade-off relationship between rise-time and oscillation of P&O and IMR. Genetic algorithm (GA) is used for finding the optimum parameters of membership functions of FLC. From the case-study of start-up of the PRO adopting MPPT control, MFC and FLC have shown faster convergence to the target performance without oscillation compared with P&O and IMR. These four MPPT techniques are further evaluated in case-studies of state transitions of the PRO due to operational fluctuations. It is proven that the MPPT using FLC and modified MFC has better performance than the other two methods. Finally, the paper reports a comparison of major characteristics of the four MPPT methods, which could be considered as guidance for selecting a MPPT technique for the PRO in practice

Design considerations of sub-mW indoor light energy harvesting for wireless sensor systems

For most wireless sensor networks, one common and major bottleneck is the limited battery lifetime. The frequent maintenance efforts associated with battery replacement significantly increase the system operational and logistics cost. Unnoticed power failures on nodes will degrade the system reliability and may lead to system failure. In building management applications, to solve this problem, small energy sources such as indoor light energy are promising to provide long-term power to these distributed wireless sensor nodes. This paper provides comprehensive design considerations for an indoor light energy harvesting system for building management applications. Photovoltaic cells characteristics, energy storage units, power management circuit design and power consumption pattern of the target mote are presented. Maximum power point tracking circuits are proposed which significantly increase the power obtained from the solar cells. The novel fast charge circuit reduces the charging time. A prototype was then successfully built and tested in various indoor light conditions to discover the practical issues of the design. The evaluation results show that the proposed prototype increases the power harvested from the PV cells by 30% and also accelerates the charging rate by 34% in a typical indoor lighting condition. By entirely eliminating the rechargeable battery as energy storage, the proposed system would expect an operational lifetime 10-20 years instead of the current less than 6 months battery lifetim