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All Grounding planning of a substation is important and various design applications are available using calculation uniform soil resistivity, even though actual resistivity data measured is more than one layer. This is caused by limited availability of the application in processing data only for resistivity one layer. Substation grounding grid application (ASPG) 1.0 can be used for designing grid grounding. The ASPG was developed from Lab View software and has ability to data process for resistivity two-layer that to refer IEEE Std. 80-2013. Grid grounding resistance is considering a combination of grid conductor and ground conductor. This paper discusses the calculation of the magnitude of substation grid grounding using formulas developed by Schwarz, Sulivan and Sunde. The design result obtained is more accurate in substitute resistivity for resistivity two-layer model and calculation grounding resistance substation.

The grounding resistance value is directly proportional to soil resistivity. The resistance value is better as low as possible for the equipment body grounding. The purpose is to provide a path of the short circuit current flows to the ground as protection and safety personal and also the equipment. The soil resistivity great is influenced by moisture and substance content in the soil. The highland soil and rocky soil commonly are poor the soil resistivity. Transmission line towers can be not avoided through the highland region. To reduce the soil resistivity value can widely be carried out by addition low material resistance (LMR) or LMR composite other materials. This research, to mitigate the value of the soil resistivity can be carried out by addition low material resistance (LMR) Zeolite composite with NaCl, Charcoal, and Soil. Various compositions of the LMR, NaCl, and Charcoal were used to find the lowest grounding resistance at certain depth. The three-point method was used to measure the grounding resistance value. The research result gives information that best composition is 90% Zeolite, 5% NaCL and 5% charcoal for the rod depth of 1.2m, the resistance decrease from 94.3Ω down to 5.3Ω (94.4%). The LMR Zeolite is dominant influence to reduce the grounding resistance.

Voltage sag is one of the power quality disturbances most frequently by customers because it can cause economic loss for the customers especially industries and commercial customers. The main source of voltage sags are faults in transmission and distribution beside two others namely motor large starting and transformer energizing, both the voltage sags have less effect on the equipment. Voltage sags can cause degradation performance of the equipment, and it depends on the magnitude and the duration. The voltage sags that occur in the power system can be compensated with installed Static VAR compensator (SVC) and Static synchronous compensator (STATCOM) in the distribution system bus. The purpose of the study is to compare both types of the device used to mitigate voltage sags in simulation using Alternative transient program (ATP) software. The voltage sag results from the short circuit faults. The method proposes the installation of the two compensator devices alternatively at one of the IEEE thirteen busses systems. The result shows the STATCOM is better than the SVC to handle mitigation of voltage sags compared with the SVC.

The primary source of voltage sags is a short circuit fault in the power system. Three-phase fault can result in a more severe effect on the equipment. The voltage sags have affected significantly on performance degradation of the induction motor. The motor behaviors can be investigated in terms of rotation speed, torque, peak current, and recovery time during and after voltage sags. This study is to investigate induction motor behavior under voltage sags using the alternative transient program (ATP) draw software in simulation models. Distinct rated capacity, mechanical inertia, and loads torque (constant, linear, and variable) of the motor were used to investigate the motor’s behavior during and after sag end. Voltage sags resulted from three-phase fault at the certain locations in industrial power systems. The motor rotation speed decreases in slightly distinct during voltage sag but recovery times required to motors are longer for the large capacity motors. The large motors create the larger inrush current can reach more than five times its nominal. The motors with constant load toque subjected to voltage sag lead loss control in speed.

Lightning has always been a dangerous threat to power system equipment consisting of: power plants, substations, transmission lines and distribution lines. Commonly, the overhead high voltage transmission line is subjected to lightning strikes. Therefore the protection level against lightning is determined based on the level of insulation of equipment. To prevent damage due the equipment due to a lightning strike, an arrester is used. In this study, three models of arrester are used as comparison viz. IEEE arrester model, Micaela arrester model and Karbalaye arrester model. The system were simulated by using the Alternative Transients Program (ATP) software. The results show that the lightning arrester is declared successful in protecting the transmission system, where the three lightning arresters have Margin Protection (MP) arrester which reaches 28%. In the simulation, it is known that the IEEE and Karbalaye arrester successfully breakdown the lightning current in transmission system so that the transient overvoltage recorded on the transformer does not exceed the Basic Insulation Level (BIL) value of the transformer. While the Pincenti arrester has also succeeded in reducing the voltage on the system but its value is greater than the transformer BIL of the substation, Teluk Dalam, Nias

The increase in load which increases every year causes a decrease in voltage on the line which is getting bigger. The voltage drop on the transmission line greatly affects the quality of the voltage. The voltage that arrives at the electrical equipment will decrease which in turn reduces the performance of the equipment. The power flow study uses the Fast Decoupled method, the voltage on each bus can be determined. The performance parameters observed are the value of the power factor, voltage, active power, and reactive power to determine the parameters for the location and size of the capacitor bank capacities and the static var compensator (SVC). By increasing the power factor in the range of 0.85pu to 0.95pu, the bus voltage can fulfill the SPLN standard. Parameters are designed and simulated using the ETAP programming software version 12.6.0 by testing each bus that experiences a voltage drop in turn based on the voltage limit and the power factor value ≤ 0.85pu. Furthermore, several buses with the appropriate capacity rating are selected to increase the voltage on the system. The simulation results will show the effectiveness of the capacitor bank and static var compensator (SVC) to increase the voltage value on each bus.

Computation of the generator neutral grounding system through a distribution transformer can be done through manual calculations. A lot of data is used in calculations so that the possibility of recurring calculations. This is very difficult and causes a large difference in the calculation results. Therefore, a computer-based computing system is needed to overcome problems like this. Several papers have been developed on the calculation of the voltage capacity through medium grounding, the length of the electrodes attached to the ground of the generator, one-phase faults to the ground, and zero sequence current disturbances. Therefore, this paper discusses modeling using the LabView Graphical User Interface (GUI) application to create it easier to design neutral grounding for equipment. As an implementation, modeling using Std. C62.92.2TM-2017 data and the results of the generator neutral grounding design can be easy, faster, and more accurate.

This paper presents the influence of distributed generation (DG) location and capacity for mitigating voltage sag caused by faults. The voltages sags are caused by the faults were simulated on the IEEE 13 bus system for single line to ground close to 650 and three-line phase faults at bus 646 using Alternative Transient Program (ATP) software. The voltages are monitored at every buss system. The DG is installed for one DG, two DG and three DG as the alternative. The DG locations are installed based on trial and error. DG total capacity is 2/3 load total installed in the system. As the alternative DGs installed viz. for one DG at Bus 611 with the capacity of 2.5 MVA; Two DGs at Bus 611 and Bus 680 with their respective capacities of 1.25 MVA; Three DGs are located at Bus 611, Bus 680 and Bus 633 with their respective capacities of 1 MVA. The results show that DG location placement in many locations gives the better results for mitigating voltage sags.

The voltage drop in distribution line unavoidable but can be reduced until the allowable limit. The voltage drop occurred due to currents flow in impedance lines. Harmonics caused by non-linear loads that are often found in the industrial used electronics devices. This study is to discuss the application of static var compensator (SVC) to improve the power quality in distribution lines. Harmonics analysis of the loads industries are modelled as arc furnace and adjustable speed drive (ASD) using software ETAP simulation. The loads are connected to the IEEE 14 busses system. Fast decoupled method was used for investigating the voltage drop at each buss. Harmonics analysis was carried out to find harmonics level contents i.e., total harmonics distortion of voltage (THDV) and current (THDI). Values of THDV and THDI resulted are evaluated by state electrical company (PLN) standard. The load flow study result shows that there are some busses have voltage below the standard and harmonics analysis beyond the allowable limit but the voltage at Bus 14 is lowest, therefore SVC is connected to it. The results show all the voltage is fulfilling the standard. The SVC installation on this case is less significant it affects on mitigating harmonics.