Science Education

The direct torque control theory has achieved great success in the control of BLDC motor and PMS Motor. Many researches was carried out to apply the idea of DTC of BLDCM to PMSM since 1990's.The DTC is applied by choosing the appropriate voltage vector based on the switching status of inverter which was determined by the error signals of reference flux linkage and torque with their measured real value acquired by calculating in the stationary reference frame by means of simply detecting the motor voltage or currents. Aiming at the DTC in PMSM Drives, this research presents the theoretical basis of the DTC for PMSM firstly. Then the difference between the application of DTC to PMSM and to BLDCM, their model on the rotor reference frame with their respective motor equations was explained and presented.

The direct torque control theory has achieved great success in the control of BLDC motor and PMS Motor. Many researches was carried out to apply the idea of DTC of BLDCM to PMSM since 1990's.The DTC is applied by choosing the appropriate voltage vector based on the switching status of inverter which was determined by the error signals of reference flux linkage and torque with their measured real value acquired by calculating in the stationary reference frame by means of simply detecting the motor voltage or currents. Aiming at the DTC in PMSM Drives, this research presents the theoretical basis of the DTC for PMSM firstly. Then the difference between the application of DTC to PMSM and to BLDCM, their model on the rotor reference frame with their respective motor equations was explained and presented.

Abstract: The direct torque control theory has achieved great success in the control of BLDC motor and PMS Motor. Many researches was carried out to apply the idea of DTC of BLDCM to PMSM since 1990’s.The DTC is applied by choosing the appropriate voltage vector based on the switching status of inverter which was determined by the error signals of reference flux linkage and torque with their measured real value acquired by calculating in the stationary reference frame by means of simply detecting the motor voltage or currents. Aiming at the DTC in PMSM Drives, this research presents the theoretical basis of the DTC for PMSM firstly. Then the difference between the application of DTC to PMSM and to BLDCM, their model on the rotor reference frame with their respective motor equations was explained and presented.

The distribution transformer monitoring system is composed of Transformer Terminal Unit (TTU), GPRS wireless communication network and master station. TTU is installed in the transformer, which mainly accomplishes data collection, analysis and record, pops up alarm information in time when the transformer has abnormal events, receives the command from the master station and implements it. GPRS wireless communication network is the bridge of data transmission between the master station and transformers. Master station receives the real-time data of transformers through GPRS wireless communication network, implements further data processing and saving, consequently issues control command. Therefore the system can achieve a comprehensive monitoring and control for distribution transformers. At the same time, it can provide users with a visual interface and let dispatches obtain monitoring performance of far transformers in time for never leaving home. Choosing an appropriate device should also be considered when designing and low power consumption components. From replacement and easy maintenance considerations and reliability, the controller part is independent chassis equipment. We focus on the selection of hard ware component and corresponding hardware design of TTU, designing a high reliability and multifunction TTU which meet the application requirements is an urgent need for substation automation. This paper presents a new hardware design for TTU; the design is composed of seven main parts with its own components which include: conditioning circuit of A-Phase voltage and conditioning circuit of A-Phase current, Circuit diagram of switch input. power supply regulator, Multiplexer switch (AD7506), Clock circuit design output switch control circuit and Communication interface circuit.

The direct torque control theory has achieved great success in the control of BLDC motor and PMS Motor. Many researches was carried out to apply the idea of DTC of BLDCM to PMSM since 1990's.The DTC is applied by choosing the appropriate voltage vector based on the switching status of inverter which was determined by the error signals of reference flux linkage and torque with their measured real value acquired by calculating in the stationary reference frame by means of simply detecting the motor voltage or currents. Aiming at the DTC in PMSM Drives, this research presents the theoretical basis of the DTC for PMSM firstly. Then the difference between the application of DTC to PMSM and to BLDCM, their model on the rotor reference frame with their respective motor equations was explained and presented.

Computer has become one of the most important tools in human life, in-fact it has become an integral part of human life, because of its relevance in learning, communication and information, multimedia, business and entertainments. Despite all its advantages it has posed some negative effects on humanity. This paper shows the survey conducted to actually unveil some possible effects that users of computer encountered, and the result analysis has shown a great significance in educational research and the study.

The use of hypermedia as an instructional resource has led to new and exciting opportunities for instructional
delivery in institutions of learning. Yet, traditional teaching methods dominated the established academic institutions in Nigeria.
This study explores the determinants that will predict the actual use of hypermedia instructional resources for teaching Digital
electronics courses in Nigerian universities, an explanatory sequential mixed method was adopted as the research design for the
study while Survey research was conducted on 120 electrical and electronics technology education undergraduates’ students and
lecturers. Structural equation modeling using Smart Partial Least Square-Structural Equation Modelling software was performed
to evaluate the proposed hypotheses, and a semi-structured interview was conducted and analyzed through the inherent future of
Nvivo11 to support the quantitative data. The results revealed that Perceived Usefulness and Accessibility were significant
predictors of using hypermedia instructional resources for teaching digital electronic courses. The paper recommended that the
University management, policymakers, and educational technology practitioners consider Perceived Usefulness and
Accessibility as factors that predict the actual use of Hypermedia Instructional Resources in teaching digital electronics in
Nigerian universities before investing huge amounts of funds in the development of Hypermedia Instructional Resources for
teaching and learning.

This study employs a sequential mixed-methods design to investigate the instructional benefits and challenges of using hypermedia instructional resources in Electrical/Electronic Technology (EET) education at northern Nigerian universities. The research first collected quantitative data through pre-and post-tests to assess improvements in students' academic performance. It was followed by qualitative data obtained from interviews and focus group discussions with lecturers and students to explore their perceptions, experiences, and challenges. Quantitative data analysis uses statistical methods to compare performance metrics, while qualitative data are analyzed thematically to identify recurring issues and insights. The findings revealed significant improvements in students' engagement, academic performance, and knowledge retention after integrating hypermedia resources, particularly in the practical and conceptual areas of EET. However, several challenges persist, including inadequate infrastructure, limited technical skills among lecturers, and insufficient institutional support for the adoption of technology. These barriers hinder the optimal use of hypermedia resources and reduce their potential impact. Based on these findings, this study recommends enhancing infrastructure, providing targeted professional development for lecturers, and increasing institutional investment in digital tools and training. Additionally, it suggests fostering collaboration between universities and industry stakeholders to ensure relevant and updated content for hypermedia resources. These strategies aim to maximize the benefits of hypermedia in EET education, address existing challenges, and ensure the sustainable integration of technology into the curriculum.