The basic task of railway signal work is to ensure safe and smooth transportation, improve transportation capacity, and improve transportation conditions and quality. Since it carries important information and control technology; it must be characterized by high security and high reliability. To address the aforementioned issues, this study uses a nonlinear technique to provide high-precision real-time detection of frequency shift signal parameters, based on an investigation of the sources of spectrum leakage in the FFT transformation. It not only reduces the sampling time but also the computation time when compared to the nonlinear method. This paper presents a frequency shift track circuit parameter based on nonlinear algorithm, studies the application of frequency shift signal parameter detection based on nonlinear algorithm, and simulates it with MATLAB. The experimental results show that the errors of center frequency, low frequency, and frequency offset are distributed in the range of ±0.05 Hz, ±0.005 Hz and ±0.15 Hz, respectively, which meet the parameters of frequency shift signal. The algorithm can meet the requirement of technical indexes and shorten the sampling time, which provides a theoretical basis for the design of the real-time frequency shift signal parameter tester.

A power quality problem is an occurrence which depicted as a nonstandard voltage, current or frequency that results in a failure or a dis-functioning of end use equipments causing a havoc to system performance. The aim therefore, in this work to maintain a proper voltage profile by mitigation of sag due to faults in power system occurred due to several reasons like energizing of heavy loads, transformers, induction motors, bad weather, insulation breakdown, closing & reclosing of circuit breakers. In this paper compensation of voltage sag is studied in various faults and minimize the total harmonic distortion in the transmission line.

The proposed fuzzy control method in this paper depicts for MPPT i.e. maximum power point tracking of for photovoltaic system considering the variations in irradiation and temperature active conditions. Here fuzzy control (FC) method has been compared with perturb and observe (P&O) method which is taken as one of the most user applicable conventional method applied to this area. Both techniques in the study has been analyzed, compared and simulated. Mainly fuzzy control technique provides effective and reliable operational control for PV application.