Power Generation of Pure Sine Wave in Batteryless Solar System using Advanced Control

A novel technique for conversion of DC power to AC power is introduced using solar powered sine wave generation system is presented. DC power extracted from solar system is made utilitarian for driving the BLDC (brushless DC) motor with constant speed constraints. The back EMF signals of each phase of the BLDC motor facilitated the development of technique for the sine wave generation from solar system without battery backup. This motor is coupled with AC generator, which yields the AC power on demand. The constant speed constraint indispensable for fixed electrical frequency at the output of generator. A new control technique is rendered for reference tracking speed control of BLDC motor using Lyapunov theory by changing switching frequency, and also maintaining the voltage level at the output of converter driving BLDC by regulating the switching frequency of the zeta converter. The proposed methodology for generation of AC power from solar power system is also tested on prototype. The comparison of conventional technique for generation of sine wave power and proposed scheme is mentioned at later section of this paper for describing the efficacy of newly presented scheme.

Impact of Formative Evaluation and Fixed Interval Schedule Reinforcement on Academic Achievements of Secondary School Students

Title “Impact of formative evaluation and fixed interval schedule reinforcement on academic achievements of secondary school students” The study was designed to find out the impact of formative evaluation and fixed interval schedule reinforcement on academic achievements of secondary schools students. It was experimental design and completed in two phases with the duration of 120 days, 60 days for each phase. In first phase experimental group was evaluated by formative evaluation and in second phase experimental group was evaluated formatively and also was given fixed interval schedule reinforcement. In first phase 60 students were randomly selected from 9 th class of Govt. High School Fateh Jang. This sample was divided into two equal groups. One served as control group and other as experimental group. A pretest was conducted to both the groups in the subjects of Math and English. Both groups were taught by subject specialist of Math and English. Control group was only taught and was not given any treatment whereas experimental group was taught and evaluated by teacher made test during session. After completion of 60 days teaching, a post test was conducted in Math and English. In second phase 60 students were randomly selected from 10 th class of Govt. High School Fateh Jang. This sample was divided into two equal groups. One served as control group and other as experimental group. A pretest was conducted to both the groups in the subjects of Math and English. Both groups were taught by subject specialist of Math and English. Control group was only taught and was not given any treatment whereas experimental group was taught and evaluated by teacher made test and reinforcement was given with a fixed interval schedule, after every six days, during session. After completion of 60 days teaching, a post test was conducted in Math and English. It was found that formative evaluation and fixed interval schedule reinforcement has significant relationship with learning and academic achievements in the subjects of Math and English at secondary school level. It is recommended that educational institutional management may arrange capacity building programs for teachers to familiarize them with evaluation, its importance and its process. The iimanagers of educational institutions may monitor teaching learning process with a view to implementing formative evaluations policy. Curriculum designers and developers may design and develop formative evaluation tools within curriculum documents for each subject keeping in view the requirements of fixed interval schedule reinforcement in the manuals for textbook instruction.