MATLAB/Simulink/SimPower Systems

Today, the use of electronic equipment in various applications in industries has increased. The equipment is used in variable speed electric drives, power quality enhancements, high-voltage direct current lines, connecting new energy sources to the grid and many other applications. The capability of electronic power equipment is to operate at flush voltages and withstand currents of up to 1 kA. Increasing these capabilities have made them available for use in power distribution and transmission networks. When these power electronics are connected to the grid, their current is not completely sinusoidal and is accompanied by different harmonics. On the other hand, this current passes through the impedance of the transmission line and the impedance of the transformers, causing losses and reducing voltage and distortion in the grid. The presence of this harmonic in the system causes heat loss, Decrease network equipment efficiency, undesirable performance of electronic equipment, the possibility of resonance in the L and C elements of the network, adverse effect on telecommunication systems and devices that are sensitive to voltage.

The fault event in power systems is a common occurrence and it is not possible to design and run an electrical network where the fault does not occur. Therefore, the protection system must respond to the smallest fault current, as the fault current stays in the network at all times, increasing the network damage and the probability of network instability due to damage at the fault site and the risk of developing ground fault flow to healthy phases. . So detecting and fixing errors quickly will help greatly improve network status. Power grids across the country are vast in scope, due to the presence of consumers and the sensitive loads attached to them, providing attention to protecting the system against disturbances and errors. On the other hand, the reliability index of the power system, which determines the level of use and connectivity of the consumer, is therefore evaluated in order to increase system capability in disturbances. For this purpose, a variety of perturbations and errors that reduce the reliability as well as the power quality of the system are considered and categorized and constrained. The study in this paper is based on transient power system errors in transmission and distribution. MATLAB \ SIMULINK software examines and errors in the power grid and its impact on grid connected loads and analyzes the grid quantities. The model presented in this study is a complete model to investigate the effect of power system errors with the presence of different ohmic, selfie, capacitive loads.