A novel method to optimize permanent magnet assisted synchronous reluctance machines

This paper presents the characteristics of permanent magnets in a synchronous reluctance machine by employing analytical and finite element methods. Four possible designs are studied and their characteristics are compared against a base synchronous reluctance machine with linear barriers to reveal machine characteristics. Then, the paper proposes a novel optimization topology to optimize permanent magnet synchronous reluctance machine as a single object for better machine performance. An explicit investigation is conducted to reveal the operational behavior of the machine such as torque, power factor and torque ripples with various machine parameters and compares them with the base design. The study reveals that permanent magnet synchronous reluctance machine can be optimized to have significantly high-power factor and torque with acceptable torque ripples

Lithium-ion battery thermal management systems : a survey and new CFD results

The environment has gained significant importance in recent years, and companies involved in several technology fields are moving in the direction of eco-friendly solutions. One of the most discussed topics in the automotive field is lithium-ion battery packs for electric vehicles and their battery thermal management systems (BTMSs). This work aims to show the most used lithium-ion battery pack cooling methods and technologies with best working temperature ranges together with the best performances. Different cooling methods are presented and discussed, with a focus on the comparison between air-cooling systems and liquid-cooling systems. In this context, a BTMS for cylindrical cells is presented, where the cells are arranged in staggered lines embedded in a solid structure and cooled through forced convection within channels. The thermal behavior of this BTMS is simulated by employing a computational fluid dynamics (CFD) approach. The effect of the geometry of the BTMS on the cell temperature distribution is obtained. It is shown that the use of materials with additives for the solid structure enhances the performance of the system, giving lower temperatures to the cells. The system is tested with air-cooling and water-cooling, showing that the best performances are obtained with water-cooling in terms of cell packing density and lowest cell temperatures

Performance comparison of various probability gate assisted binary lightning search algorithm

Recently, many new nature-inspired optimization algorithms have been introduced to further enhance the computational intelligence optimization algorithms. Among them, lightning search algorithm (LSA) is a recent heuristic optimization method for resolving continuous problems. It mimics the natural phenomenon of lightning to find out the global optimal solution around the search space. In this paper, a suitable technique to formulate binary version of lightning search algorithm (BLSA) is presented. Three common probability transfer functions, namely, logistic sigmoid, tangent hyperbolic sigmoid and quantum bit rotating gate are investigated to be utilized in the original LSA. The performances of three transfer functions based BLSA is evaluated using various standard functions with different features and the results are compared with other four famous heuristic optimization techniques. The comparative study clearly reveals that tangent hyperbolic transfer function is the most suitable function that can be utilized in the binary version of LSA

The Unconventional Strength Towards STEM Cohort

Science, Technology, Engineering and Mathematics (STEM) play a critically important role in Australia’s ability to innovate, expand and remain a competitive force globally. Indeed, ensuring that the workforce has the relevant skills in sufficient quantities through a reliable educational pipeline is quite challenging and requires an understanding of how these skills are and will be used within the Australian economy. Moreover, successfully delivering these skills for a knowledge economy will depend not only on producing the correct number of graduates but also on the education system supplying graduates from under-utilised groups (i.e. women & indigenous people) and diverse backgrounds. Currently, millions of children and young people are not developing the required skills to participate effectively in STEM environments. Young indigenous and female groups, in particular, are deprived of the opportunities to build their skills, including STEM literacy that is valued towards career progression in traditionally male-dominated fields (i.e. engineering and construction). As this white paper outlines, the challenges are drawn from recent literature, and a comprehensive review of existing initiatives is presented based on the observations of key partners, including Western Sydney University, the Australian government, research sector, industry, policymakers and communities. However, to build the STEM capacity of graduates with the right knowledge, competencies and qualities, two-way collaboration between the communities, educational institutions (from an early age), Australian workplaces and the government is essential, as no single sector can entirely solve the current STEM skills shortage. Western Sydney University is well-positioned within the high-density indigenous areas to respond to these issues, particularly by monitoring, engaging and promoting all graduates with STEM qualifications to meet the demand from the economy. In fact, by supporting equity and diversity throughout the STEM cohorts, educational institutions not only drive innovation but also establish a thriving STEM-skilled workforce that is fit for the future

Design optimization and simulation of hybrid renewable energy systems

Hybrid renewable energy systems (HRES) are commonly being implemented in off-grid and in-grid systems, although modulation techniques haven't yet been fully explored to predict the cost-effectiveness of the overall system.In this paper, optimization techniques will be explored, with the implementation of hybrid optimization of multiple energy resources (HOMER) and improved hybrid optimization by genetic algorithms (IHOGA), combined with a test case of graphical analysis, and system definition based on the load coverage rate (LCR) and modulation of each system connected to the grid individually using MATLAB and SIMULINK. The system simulated was designed to be implemented at Western Sydney University, Werrington South Campus and the system's power flow management, was based on the load from the building Z of the Western Sydney University Kingswood campus

OHEW earthing design methodology of traction substation

Electrical railway system relies on the traction substation to enhance its voltage operation. Performing High Voltage (HV) maintenance with a multicraft work force creates a special set of safety Challenges. The safety aspect will be discussed in this paper from an earthing point of view. An effective approach to design the earthing system of the traction substation will be proposed and explained. Finally, this paper provides an analytical example to the proposed method

AC interference study on pipeline : the impact of the OHEW under full load and fault current

Electrical Safety as a result of induced voltage is gaining more attention in the area of HV utilities. This paper discusses the Electrical safety in a pipeline running parallel to a HV transmission line, and the methods of calculating the mutual impedance between the HV and pipeline. In addition, it also introduces a method of calculating the induced voltage in the pipeline and its mitigation process

Density monitoring of high voltage SF6 circuit breakers

As a circuit breaker ages it becomes more susceptible to SF6 leaks. Retrofitting density monitoring equipment to existing circuit breakers allows for the early detection of a SF6 leak before a low pressure alarm is raised. This report analyses different aspects of density monitoring which need to be considered to successfully retrofit a SF6 circuit breaker with density monitoring equipment. These aspects include sampling rate, what type of transducer to use and how to interpret the density measurements to detect SF6 leaks

Designing a lightning protection system using the rolling sphere method

Lightning is a natural occurring phenomenon that can cause damage harm and fatality. This paper discusses the lightning protection of a property using the rolling sphere method. In addition, it introduces an easy approach on how to design an effective lightning protection and finally it provides a case study

Improving security between nodes in wireless ad-hoc networks

The operation of Ad-hoc networks depends on the cooperation among nodes to provide connectivity and communication routes. However, such an ideal situation may not always be achievable in practice. Some nodes may behave maliciously, resulting in degradation of the performance of the network or even disruption of its operation altogether. To mitigate the effect of such nodes and to achieve higher levels of security and reliability, this paper expands on relevant fuzzy logic concepts to propose an algorithm to establish quantifiable trust levels between the nodes of Ad-hoc networks. These trust levels are then used in the routing decision making process. Using OPNET simulator, the proposed algorithm is validated and further studied. The findings show that when the proposed algorithm is utilised, the overall performance of the Ad-hoc network is significantly improved