This paper investigates the impact on operating time delay and relay maloperation when 1,2 and 3 order analog antialiasing filters are used in numerical distance protection. RC filter with cut-off frequency 90 Hz is used. Simulations are carried out for different SIR (Source to line Impedance Ratio), load, fault type and fault conditions using SIMULINK, where the voltage and current signals are...

This paper examines various aspects of the design process and subsequent field test measurements of a large and complex substation grounding system. The study and measurements show that soil layering and lead interference can have a significant impact on the appropriate test location that yields the exact substation ground impedance. Applying a specific percentage rule such as the 61.8% rule fo...

(paper pages 133-156) zagros active fold-thrust belt lies on the northern margin of the arabian continental crust it is a young fold-thrust mountain belt currently shortening, thickening and uplifting as a result of the collision of the arabian and iranian plates. rethickening of crust during collisional orogenies could have been carried out by reversal of fault motion along the mesozoic normal...

To delineate the spatial distribution of high saturation gas hydrate reservoirs in low-angle subduction areas Makran Accretionary Prism, we conducted seismic data interpretation and impedance inversion hydrates Prism comprehensively analyzed characteristics Nankai Trough Japan Shenhu Area South China Sea. The results show that features thick sediments, developed transport systems “two-way suppl...

This paper focuses on a hybrid islanding detection algorithm for parallel-inverters-based microgrids. The proposed algorithm is implemented on the unit ensuring the control of the intelligent bypass switch connecting or disconnecting the microgrid from the utility. This method employs a grid impedance estimation technique that uses resonance excitation once grid fault occurs. It includes two st...

Varieties of fault location algorithms, differing in many aspects, have been developed so far. Huge majority of them, including the algorithm presented in this paper, belongs to the family of impedance based algorithms. In these algorithms the impedance parameters of a line are taken as the measure for a distance to fault. Basically, voltages and currents from one end or from all terminals of a...

The knowledge of DC time constants in fault currents at system nodes is important to design the protection system and validate the calculation models for power system simulations. In this paper, we present methods to estimate Thévenin’s impedance and DC time constants in fault currents with application to disturbance records. Additionally, a comparison between both parameters is shown. We demon...