Khalid S. Al-Olimat

Electricity markets: an overview and comparative study

Purpose – The electric power industry has been moving from a regulated monopoly structure to a deregulated market structure in many countries. The purpose of this study is to comprehensively review the existing markets to study advantages, issues involved and lessons learnt to benefit emerging electricity markets.Design/methodology/approach – The paper employs a comprehensive review of existing competitive electricity market models in USA (California), UK, Australia, Nordic Countries (Norway), and developing country (Chile) to analyze the similarities, differences, weaknesses, and strengths among these markets based on publically available data, literature review and information.Findings – Ongoing or forthcoming electricity sector restructuring activities in some countries can be better designed based on lessons learnt from existing markets and incorporating their own political, technical and economical contexts. A template for design of successful electricity market has also been presented.Research limit...

Modeling and control of a micro-grid set up using photovoltaic arrays

This paper presents a complete mathematical model of a micro-grid set up with PV arrays. The model consists of mathematical design and development of PV module and arrays, power conditioning DC/DC converter and the inverter set up. These designs are integrated with an inverter controller that controls the voltage at a power system bus. The complete system is used as a micro-grid set up connected to a power grid. Testing and evaluations of the micro-grid is then conducted using off-grid and on-grid studies. The uniqueness of the proposed modeling and control includes a complete models details of micro-grid set up with PV system, power conditioning devices and load model, the utilization of an MPPT and feedback controller to control the output voltage and current. Thus it provides an appropriate real-life testing platform for micro-grid connections to power grid. Simulation results show the effectiveness and the accuracy of this micro-grid model to emulate real-life scenarios.

Engineering student-design competition teams: Capstone or extracurricular?

Year after year, engineering student-design competitions continue to attract increasing attention from engineering programs across the country. The participation in these competitions is beneficial to both students trying to develop their design and networking abilities, and institutions trying to promote their programs and increase their visibility. Traditionally, the perception has been that the easiest, most straight forward way to participate in a student-design competition is to assign the competition project as a capstone senior design project. This way, a group of seniors work under the supervision of a faculty member to complete the project seeing that the completion is a graduation requirement. The recently emerging alternative is to form an extracurricular team of students whose goal is to exclusively participate in the competition. The extracurricular teams are mostly populated by sophomore and junior level students and driven only by their passion and self motivation rather than a curricular requirement. In this paper, we share our observation and experience to contrast both options and provide some recommendations.

Comparison of multilevel DC-DC converter topologies

Multilevel DC-DC converter systems are used to transform low level DC voltages to larger DC voltages. Different topologies of multilevel DC-DC power converters such as cascaded model, one-to-many model and general multilevel DC-DC converter modules are studied and compared. These topologies are compared in terms of the number of discrete steps of output voltage levels, number of switching elements, and the ease of converting between different voltage levels.

Induction Motor Speed Control via Fuzzy Logic Modification of Reference Model

A novel model reference adaptive control scheme using reference model modification through fuzzy logic to control the speed of an induction motor is presented. This scheme is developed to cope with uncertainties and disturbances that the plant under control might undergo where a single reference model can not handle. The main concept of the proposed philosophy is to ensure automatic change of the controller parameters so that they correspond to the current plant environment and provide an appropriate control action to improve the overall control system performance. This is carried out through a fuzzy logic evaluation block whose input signals are the command signal and an auxiliary output at each sampling interval. This information is then used in the fuzzy rules to compute the proper values of the reference model parameters for that instant. The effectiveness of the proposed technique is demonstrated through computer simulation. The obtained results fully confirm the validity of the proposed scheme.

Inculcating an entrepreneurial mindset in engineering education: Project approach

In a competitive global economy, it is important for engineering students to develop entrepreneurial skills that include effective collaboration and communication, persisting and learning from failure, management, and solving ambiguous problems. This paper summarizes a project that aims to instill these skills as part of an entrepreneurial mindset in engineering students. The project was implemented in an introductory electric circuits class with a mixed representation of students majoring in electrical, computer, civil, and mechanical engineering. Students were organized into groups of two or three to design a temperature sensor using a negative temperature coefficient thermistor. Students groups were provided with customer specifications and were given a month to research the problem and obtain a viable solution. The groups were required to provide evidence compiled into a written product proposal that included a bill of materials, cost analysis, circuit design and simulation, testing plan, layout of the printed circuit board and packaging schematic, delivery time, and the voltage-temperature relationship of the designed circuit. After submitting the written proposal, each group was given five minutes to pitch their proposal using a poster in an effort to convince the customer (in this case, the instructor) that their design was the best and most cost-effective solution.

Fuzzy Logic Control Systems

This article explains fuzzy controllers and general fuzzy systems. It emphasizes the basic idea of fuzzy control and the mathematics behind the concept. The article is divided into two sections. In the first part, the mathematics of fuzzy systems is discussed, which includes the definitions and basics of fuzzy expert systems, general fuzzy systems, and their properties. In the second part, the concept of fuzzy control are detailed which include the selection of inputs and outputs, enhancing control knowledge as a rule base, determining which rules to use, determining conclusions, converting decisions into actions, and graphical visual representation of fuzzy control operation. Then, various fuzzy control techniques and the essence of how fuzzy systems can be used for a wide range of control architectures are explained. The article concludes with the summary and future prospects of fuzzy logic systems. Keywords: fuzzy logic; fuzzy control; fuzzy logic control; control systems; intelligent control; fuzzy systems; fuzzy sets

Power System Stabilizers with Fuzzy Logic Switching

A self-tuning regulator (STR) with multi-identification models and a minimum variance controller that utilizes fuzzy logic switching is presented. The STR employs recursive least squares algorithms with different order identification models to best model the plant at any given time interval, and an error minimization algorithm will select the one model that has the least identification error in comparison to the plant output. This controller design is applied to a synchronous machine in order to control the speed. The performance of the control system using the proposed scheme shows an overall improvement in comparison to those of existing stabilizers as well as classical STRs

Intelligent parallel controller based on fuzzy linguistic rules assessment

An intelligent parallel regulator is proposed to improve the performance of electric power systems. The improved stabilizer consists of a conventional power system stabilizer (PSS) working in parallel with a selected adaptive PSS. A fuzzy logic assessment block performs the functional paralleling of the two controllers to achieve a desired performance. The effectiveness of the proposed stabilizer is demonstrated through simulation studies for selected different operating conditions.

System design: A novel, project-based course connecting the dots of the electrical engineering curriculum

The four year curriculum of the Electrical Engineering program includes a fairly diverse set of classes covering topics including electronics, electromagnetics, signal processing, power & energy, digital systems, as well as communication and control systems. While these topics constitute the core components in the technical education of a future electrical engineer, a major missing component is the holistic, system understanding of these individual topics. This paper describes a class addressing the integration of the technical topics in addition to defining the overall architecture, the modularity of complex systems, as well as the interfaces between the different components to satisfy design requirements. The new class is a project-based, one credit-hour class with a single weekly meeting in a laboratory environment. The paper describes the assigned projects as well as their proposed solutions. The paper also includes assessment data including student feedback from the first class offering. Assessment shows a great student enthusiasm towards the class. It also shows that the class improved the students conceptual knowledge, knowledge retention, and problem solving skills.