The mentoring process of power engineering undergraduates through industry placement : a real-life experience from electrical power engineering consulting sector

Power engineering education has been the focus of various researchers and academics over a long period of time. Various approaches have been attempted and their outcomes have been reported. Central Queensland University implemented a Project Based Learning model and came up with a fully integrated Bachelor of Engineering cooperative/Diploma of Professional Practice in 2004. Solid industry placement components integrated into the academic program is a main feature of this model. Various industries all over Queensland host the undergraduates and mentor them while they are based in their organizations mainly by involving them in teams that comprise of experienced engineers, undertaking regular engineering professional jobs and activities. The author of this paper spent nearly four months in an industry placement in one such company providing electrical engineering consulting services, which also hosts undergraduates in their industry placements. This paper describes the methodologies power engineering consulting sector uses in mentoring the undergraduates, their effectiveness and strengths through the real-life observations the author made

Significance of energy storages in future power networks

As a result of the major challenges the world is facing today due to global warming and the ever decreasing conventional sources of energy such as fossil fuels, developing methodologies for harnessing all possible forms of renewable energy has become a heavily researched area within the power and energy research communities. Deploying energy storages increases the possibilities of harnessing several sources of renewable energy in a more meaningful manner. Some of the key areas where energy storages could make things better, when it comes to harnessing renewable energy sources are, Wind energy, Bio energy, Geothermal energy, Solar energy and Wave energy. The paper investigates application examples of energy storages in these areas through a thorough review of reported scientific literature. On the other hand, major energy consuming areas such as transportation, manufacturing, electricity consumers etc. could also benefit by the introduction of energy storages. As an example, in transportation, increasing usage of hybrid electric vehicles, plug-in electric vehicles and emerging new concepts in transportation such as electric highways have raised the significant role of energy storage solutions for transportation to its highest level. It is believed that this way of looking at the energy storages will strategically position them with the significance they deserve within the energy and power engineering research community. © 2017 The Authors

Energy efficient variable speed drives empowered with torque estimation

The induction motor (or asynchronous motor), which is the most widely used Alternating Current (AC) motor in industry, always relies on a small difference in speed between the stator-rotating magnetic field and the rotor shaft speed called slip to induce rotor current in the rotor winding. As such, the induction motor cannot produce a torque at synchronous speed, where slip ceases to exist. A motor when allowed, will provide a torque up to its maximum limit to rotate its load; especially under locked rotor or heavily loaded equipment scenarios. The value of the maximum torque limit is different for each AC induction motor and it is directly dependent on the motor characteristics. In some cases, such as conveyors, motorized lathe machines, or direct-coupled motor drives, if the motor is allowed to exercise maximum torque, it can lead to irreversible damage to the equipment. This paper presents the design of a Variable Speed Drive (VSD) system having the possibility of measuring the rotor speed and controlling the torque of an asynchronous motor to be within specified torque limits

Dynamic brush placement of large dc machines in mining industry : a feasibility study

Abstract—Large direct current machines have been used in the mining industry for many years due to their practicality and simplicity. The operational nature of DC machines causes a shift of the electrical neutral axis in the armature of the machine, changing the ideal position of the commutating brushes and possibly causing sparking. Direct current machine technology has been well developed to contain compensating windings and interpoles, which counteract armature reaction. However, there has never been a system designed to compensate for the rotation of the electrical neutral axis due to armature reaction. This paper outlines four alternate options, which could be used to design a device, which rotates the brushes of the machine with the changing electrical neutral axis. The paper also presents a comprehensive analysis of the benefits of such a device. The technical details of each option are identified along with a discussion of the designs. These four designs are then comparedusing an unbiased decision making tool resulting in the selection of most practical and effective design

Estimating signal strengths prior to field trials in wireless local loop networks

One issue in giving WIRELESS LOCAL LOOP connections in a rural area is the difficulty of conducting field trials due to poor road conditions and the hilly terrain in Sri Lanka. Extremely poor condition of access roads reduces the efficiency of giving new wireless subscriber connections. Even though at the installation of a base station, the coverage area is defined (around 20 Km radius from base station) due to the hilly and mountainous terrain in Sri Lanka signal strength varies drastically for about 100 m change of distance. There are number of Radio network planning tools or Wireless calculators in the industry with real time corrections like body losses, penetration losses and thermal noise density. But when we apply those in Sri Lankan context, we do not get the correct coverage diagrams. Therefore we propose two new path loss exponents which is suitable for countries like Sri Lanka where the population spread in hills and mountains

Biologically realistic walking pattern emulator using linear electro-mechanical actuators with augmented nonlinear control

The hind leg movement of a cat has four basic phases called Stance, Lift off, Swing and Touch down. In this research project, the complete movement of each hind leg in a vertical plane is assumed to be obtained by proper activation of seven muscles. The final target here is to propose suitable design suggestions for a linear electromechanical actuator, which could successfully emulate dynamic properties of a muscle, when augmented with nonlinear behaviours of real muscles using control. This paper will describe the proposed control methodology

Improving condition monitoring & fault diagnosis strategy for HV motors in coal fired power stations

High voltage induction motors at Gladstone Power Station are roughly 30 years old and are a significant asset and critical component to the electricity generation process. Due to the criticality of the high voltage motors in the electricity process, age and environmental conditions the motors are exposed to, how can all the high voltage motors at Gladstone Power Station be maintained and monitored regularly and more effectively particularly between scheduled overhauls is an important issue. This paper outlines the process taken to assess the current condition of the high voltage motors and evaluate the maintenance strategy utilized at Gladstone Power Station. Thermography and thermal imaging was used to assess the current condition of the motors and assess the maintenance strategy utilized. From these result, thermography was recommended to be conducted on a regular basis in coordination with other condition monitoring techniques to monitor and track the condition of the high voltage motors during on-line conditions and in between the four yearly unit overhauls. This will increase proactive and preventative maintenance techniques and ensure Gladstone Power Station are aware of the condition of all of the high voltage motors to further maximize and optimize the stations output and assets

Peak shaving approach of distribution network

The modern power system network comprises distributed generations of renewable sources. The intermittent nature of renewable sources may not always support the peak demand of the electricity network; therefore the integration of storage batteries can support the peak demand for retaining power system stability. The battery of fast charging loads like electric vehicles (EV), electric ferries (EF) and others can also be used for peak shaving of the power system. The storage elements can provide FCAS (frequency control ancillary service) to the power system for restoring the system's stability. To justify the peak shaving option of storage battery, a 9-bus system electrical network is created by OpenDSS which analyzes the charging and discharging characteristics of the battery. The storage controller controls the storage batteries in two modes, one follow-time (discharging and charging) mode and another load-shape (charging and discharging) mode. The storage controller controls the sequence of operation of the batteries to meet the load demand of the electrical network. The proposed approach can be used for a large electrical network to manage the peak demand to retain power system stability

Use of maximum demand principles for optimizing transformer design of a ship loader

To determine maximum demand currently and most widely used method in Australia is to simply follow Australian Standard guidelines and sum together the loads and find a suitable transformer rating. This practice is considered to have many flaws specifically from a construction and financial point of view and it is this lack of diversity, which this paper will be focusing on. Because of not giving due consideration for diversity, many transformers are largely oversized and as such can easily put strain on low budget contracts issued by clients as larger transformers not only cost more for the unit itself but will also increase structural support costs to adequately support the increased size and weight that the unit will have. The difficulty in attempting to create a more optimized transformer design is attributed to having to understand the ship loader operations at key intervals since maximum demand is the maximum load at certain time intervals. This paper outlines the process undertaken to lower the maximum design electrical load for the transformer of the ship loader. It also provides redesigned transformer specifications, which will be compared with specifications of similar designs carried out without considering diversity

Optimization of transmission line right-of-way

A specific land is required to design the transmission line to construct effectively and maintain properly is called right of way of transmission line. It is calculated by considering mainly three electrical quantity related transmission line such as electric field, magnetic field and radio interference. Corona effect is considered for the evolution of right of way. By considering these parameters, it provide idea related to effect surrounding the area nearby transmission line