by Huaiyi Chen, Xuehong Wu, Yixi Chen, Guchao Xu and Gang Ma
Original Research
Auxiliary power supply system is an important component of traction trains. Voltage fluctuation of auxiliary power supply system is a nonnegligible factor threatening the safe operation of traction trains. This paper based on electric spring theory aims to stabilize the voltage of the critical load in traction train auxiliary power supply system. And a method of stabilizing the voltage of the critical load with the electric spring is proposed. In this paper, a simulation model is established by Matlab/Simulink to verify the validity of the electric spring. The simulation results show that the electric spring can effectively mitigate the voltage fluctuation of the critical load, ensuring the critical load to work with a steady voltage.
American Journal of Electrical and Electronic Engineering. 2016, 4(6), 182-186. DOI: 10.12691/ajeee-4-6-5
Pub. Date: January 05, 2017
19164 Views3144 Downloads2 Likes
by Sambandh Bhusan Dhal, Arun Agarwal and Kabita Agarwal
Original Research
Science and technology has always played a prominent role in comforting human lives. The main objective of this work is based on mollifying the disabilities of blindness by creating a microcontroller based automated hardware that can ratify a visually impaired person to detect obstacles in front of him/her instantly and guide him/her in a proper way to reach his/her destination. The hardware consists of a microcontroller integrated with Arduino Uno board, microcontroller, ultrasonic sensor, GPS module, GSM module, serial driver, buzzer, LED and other additional equipments. It acts as a better navigational tool for the visually impaired. The sensors used in this model provide information about the outside environment. GPS Technology is integrated with pre-programmed locations and it is sent to the desired number through GSM module when required. This presents a design and a system concept to provide smart electronic aid for blind people. The aim of the overall system is to produce an economic and productive navigation aid for the visually challenged which can give them a sense of artificial vision and object detection by providing information about the environmental scenario of static and dynamic objects around them. Ultrasonic sensors are used to detect obstacles from a distance so as to guide the blind perso in the right path.
American Journal of Electrical and Electronic Engineering. 2016, 4(6), 177-181. DOI: 10.12691/ajeee-4-6-4
Pub. Date: December 28, 2016
17154 Views3357 Downloads
by Protik Chandra Biswas and Bashudeb Chandra Ghosh
Original Research
Permanent Magnet Brushless DC (PMBLDC) Motors are trapezoidal shaped back EMF permanent magnet AC machine with high power density. Since the motor has a trapezoidal field pattern rather than sinusoidal it is desirable to study the motor behavior under different current fed conditions to analyze the developed electromagnetic torque. In this paper three different trapezoidal, square and sinusoidal current fed field oriented vector controlled PMBLDC motor drives are presented. The novel approach of this paper is that, the torque handling capacity of a PMBLDC motor can be increased up to its rated torque by only changing the pattern of reference current of a field oriented vector controlled PMBLDC motor drive. Adaptive PI controller based on motor speed error is also proposed in the paper to have a simplified drive system. When square and sinusoidal reference current fed vector controlled drives are used, the maximum torque handling capacity of a specified PMBLDC motor is 1.60 Nm and 1.55 Nm respectively. Only by using trapezoidal reference current fed drive, the maximum torque handling capacity of that specified motor can be increased to 2.0 Nm. The performance of these three different current drives are also compared on the basis of their torque pulsation. The dynamic performance of the vector controlled trapezoidal current fed drive is found outstanding than the square and sinusoidal current fed drives considering response time, load torque handling capacity, variable speed condition, settling time of the system.
American Journal of Electrical and Electronic Engineering. 2016, 4(6), 164-176. DOI: 10.12691/ajeee-4-6-3
Pub. Date: December 28, 2016
21630 Views2790 Downloads2 Likes
by Hachimenum N. Amadi and Fabian I. Izuegbunam
Original Research
This study investigated transformer loadings and failure rate in the Onitsha Electricity Distribution Network by using the Electrical Transient Analysis Program (ETAP) software 12.6 and the Statistical Package for the Social Sciences (SPSS) software 16.0. Data collected over the period 2011-2015 on the distribution network were simulated on ETAP software using the Newton-Raphson (N-R) technique to determine the transformer loadings while responses to 350 copies of questionnaire distributed among the technical staff were statistically analysed on the SPSS software to ascertain the failure rate among transformers in the network. The findings of the study show that during the 5 years period covered by the study, the sampled substations recorded transformer average failure rate of 11.7 %. It was further revealed that besides insulation issues which accounted for 24.2% of all the failures, overload (22.5%) was the next major cause of transformer breakdowns in the distribution network. The study recommends installation of more transformer units, use of high quality transformers, balanced loading of the transformers and proactive inspection and maintenance program of transformers units within the network. The outcome of this work would help electricity utilities provide more reliable and cost effective services to customers.
American Journal of Electrical and Electronic Engineering. 2016, 4(6), 157-163. DOI: 10.12691/ajeee-4-6-2
Pub. Date: December 22, 2016
18037 Views2342 Downloads
by Sambandh Bhusan Dhal, Arun Agarwal and Kabita Agarwal
Original Research
In this system, a RFID reader is used at the entry point for user authentication. A GSM module is used so that the parking slot no, the duration of parking and the fee deducted from his card is sent to the user when he exits the parking space. The lights in the parking space glow only when the vehicle is present. The system is designed in such a way that when it senses a vehicle, it starts functioning and light turns off when vehicle crosses it. The concept can be used for both basement parking and open parking lots. We have added a feature to the design that the system senses the intensity of light. During the day time, when light intensity is high, the lighting system remains off. It is possible because of the use of various motion sensors like IR Sensor, LDR Sensor, ATmega16 microcontroller and with the help of embedded C. IR Sensor detects the motion of the vehicle and allows the light to glow accordingly. LDR Sensor senses the intensity of light and makes the lights to remain off during the day time. ATmega16 is a powerful microcontroller which is used for interfacing and programming purpose which controls the whole system.
American Journal of Electrical and Electronic Engineering. 2016, 4(6), 152-156. DOI: 10.12691/ajeee-4-6-1
Pub. Date: December 10, 2016
17761 Views3540 Downloads