DC faults originate uncertainty in the progression of multi-terminal high voltage dc (MTDC). The fault current makes a rapid, sharp peak, but isolation of the entire network is not a viable solution ...under a specific fault circumstance. Rapid detection of a fault with high accuracy is essential for the reliability of the entire network. This paper proposes a fault detection scheme to sieve voltage harmonics from system voltage by using Discrete Fourier transform (DFT). Voltage harmonics rapidly employed the fault detection at the converter stations for MTDC networks without communication. The proposed scheme is also capable of classifying internal and external fault by counting the 12 th harmonic pulse count. The simulations are executed in PSCAD for four terminal MTDC transmission network to vindicate the performance of the proposed scheme. Comprehensive analysis of test results verified that the proposed scheme, in addition to rapid and precise fault detection, can also efficiently classify the nature of faults. Moreover, consequences proved its promising performance for numerous MTDC faults.
AC microgrids (ACMGs) represent a promising evolution of traditional distribution systems, driven by environmental advantages and concerns over power quality. However, detecting islanding events ...within ACMGs poses a significant challenge. In this study, we propose the utilization of the Cubature Kalman Filtering Algorithm (CKFA) to address this challenge by leveraging voltage signals at the point of common coupling (PCC). Initially, CKFA is applied to voltage signatures to compute Voltage Residuals (VR) and Voltage Harmonic Signatures (VHS) through state estimation. These estimated VR and VHS indices are then compared against pre-defined threshold settings to identify islanding states. Subsequently, a tripping decision is made based on the OR operation of both estimated VR and VHS. The proposed method demonstrates efficacy in detecting islanding occurrences under both balanced and unbalanced load/generation conditions and effectively discriminating between islanding and non-islanding conditions. Extensive simulations conducted on MATLAB/Simulink-based IEEE 13-bus test bed and UL-1741 test bed validate the effectiveness of the presented scheme. Results signify a high accuracy rate of 99.9%, tied with low computational complexity and the smallest non-detection zone (NDZ). Additionally, the time of operation for the suggested scheme is less than 1 millisecond, without any false operations, emphasizing its effectiveness in practical application.
The most essential infrastructure of today’s modern civilization is the energy system. A new energy revolution is ongoing worldwide in understanding the affordability, reliability, and sustainability ...of energy supply. One of the major challenges and opportunities considered in this energy revolution is the integration of the energy system. The varying dynamics of renewable energy production and the environmental conditions between the different energy sources are the major reasons for this challenge. Wind and solar energies are considered the best renewable sources and the foremost substitute sources for power generation. These energies are playing a vital role as alternates of nuclear energy and fossil fuels. Electricity is generated through wind energy conversion systems and photovoltaic (PV) cells. These technologies are clean and environmentally friendlier than non-renewable energies. A hybrid PV-wind generation system is more effective and consistent than a single-source system because the solar system cannot work at night or in cloudy weather while the wind speed is variable. The current study proposes an experimental-based analysis. The hardware used is the Squirrel Cage Induction Generator (SCIG) and solar panels. A boost converter is added for Maximum Power Point Tracking (MPPT) at variable wind speed and available sunlight.
The advancement in technology has significantly improved the living standard, having a direct impact on the quality of life, at the cost of ever-increasing energy demand. Renewable energy resources ...such as the Wind Energy Conversion System (WECS) provide variable power generation. The current paper presents the results of the experimental analysis on the control of the wind-generator system based on SCIG through a dc/dc boost converter for extremum power-seeking. Since the Squirrel Cage Induction Generator (SCIG) is widely used in wind industries for power generation, their performance will be compared. The proposed system can operate either on a variable or at a nearly constant speed, with higher load capacity, while its power consumption is comparatively lower. The research will enhance the wind power at different wind speeds, to acquire the extremum power point tracking system from the wind power energy system by using two different machines.
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