Main Substation Research Articles

Perancangan Time Synchronization Sebagai Alat Bantu Pengujian Intertrip Relay Distance

At the company PT. PLN (Persero) ULTG Madiun carried out many tests relay, one of which is intertrip testing relay distance. Intertrip testing relay distance is a test carried out between 2 (two) relay distance conducting bays in main substations that face each other. Intertrip testing relay distance must be done if replacement occursrelay, replacement of teleprotection equipment, changes to protection schemes, and changes to logic circuitsrelay which is related to the send or receive signal from the opposite substation. However, this test requires synchronization between two intertrip test tools relay distance at each substation. In this final project, it will be designed Time Syncronization As A Tool For Intertrip Relay Distance Testing, to make things easier for PT employees. PLN (Persero) ULTG Madiun when synchronizing two intertrip test equipment relay distance. All process control of this tool uses ESP32 Devkit V1. Meanwhile for displaying setting time for testing can be seen on the web assisted by GPS NEO-6M. The results obtained when testing the Dolopo by Ponorogo R and S phase distance intertrip relay were carried out at 12.00.00, experiencing a delay time of 0.0553 seconds when the PMT tripped. Meanwhile, the Dolopo by Ponorogo T phase distance intertrip relay test was carried out on 12.09.00 and experienced a delay of 0.0529 seconds when the PMT tripped. From two intertrip relay distance tests, the trip time delay is no more than 0.1 second.

Highwall mining productivity enhancement with energy conservation: A case study

ABSTRACT Open-cast mining in India is transitioning from closing existing mines to extracting remaining coal seams from dormant sites. Highwall machines are key to this efficient extraction process. To meet international safety and environmental standards, audits are essential. This article evaluates the power quality of the substation’s incomer, transformer, and feeder, and proposes energy-efficient changes to boost production. Tests on the main substation transformers included voltage, current, power, power factor, harmonics, and AC waveform analysis. Thermal imaging of electrical equipment was conducted to verify operating temperatures. Results were graphed for each test. The study recommends installing an Automatic Power Factor Correction (APFC) unit and lowering the tap value from 5 to 4 to improve the transformer’s power factor. It is estimated that a 4% voltage reduction will save 1% energy, while a 5% reduction will save 1.25% energy.

Design Of A Main Substation Grounding System Based On Variations In Area and Number Of Electrodes

The function of the grounding system is to limit the voltage between equipment and the ground and neutralize the voltage that arises at the ground surface due to fault currents flowing in the ground. An unsafe grounding system can disrupt system reliability and human safety in the substation area. This research aims to simulate the design of a substation grounding system with the influence of variations in location and number of electrodes installed in grids and rods in swampy soil conditions with different soil resistivity values. The impact of these parameters is on the resistance value, touch voltage, and step voltage at a weight of 70 kg by using the CYMGRD application as a medium to see the effectiveness and optimization of whether the substation grounding system with variations in the outside area and variations in the number of electrode rods meets the requirements without exceeding safe limits on systems or humans. This grounding system design is designed for two cases, namely case 1: the maximum touch voltage and maximum step voltage values exceed the permitted touch voltage and maximum step voltage, so conditions like this are included in the criteria for being unsafe and can endanger personnel in the field. Case 2: the touch voltage and step voltage values are smaller than the permitted touch voltage and step voltage values, so this design is included in safe conditions and meets the criteria for a good and safe grounding system.

Analisis Tahanan Kontak pada Pemisah (PMS) 150 kV Berdasarkan Hasil Pemeliharaan di PT. PLN (Persero) Gardu Induk Sutami

The substation is a part of the electricity distribution system from consumer generators. To maintain the operation of the substation in optimal condition, maintenance or upkeep needs to be carried out in accordance with applicable maintenance standards. One of the equipment that requires routine maintenance at the main substation is the Separator (PMS). The disconnector (PMS) functions as protective equipment installed at the main substation and functions to disconnect and connect electrical power in a no-load condition. For this reason, maintenance needs to be carried out which aims to maintain the performance of the Separator. In this practical work report, tests were carried out on the knives or contacts on the Separator (PMS) to determine the contact resistance value. Next, this value is processed to determine the value of Power Loss, Electrical Energy Loss, and Electricity Costs and to determine whether or not it is necessary to repair the Separator (PMS). The results of the 150 kV Separator contact resistance (PMS) test in the Tarahan 1 Conductor bay of the Sutami Main Substation in the R, S and Contact Resistance phases are in the normal category because they meet the permitted standards, namely R <100 µΩ. This means that the Contact Resistance tested is still in good condition and the PMS does not require further repairs and the calculation results show that the largest electricity costs occur in Phase S when the injection current is 300A, amounting to Rp. 1,098,938 and the lowest electricity costs occur in Phase R when the injection current is 100A, amounting to Rp. 89,397.

Analysis of Determining the Surge Arrester Protective Distance for Protection on 60 MVA Power Transformers at the 150 KV Main Substation in Surabaya Barat

Because it provides electrical energy to customers that require protection from lightning interference, the substation is a crucial location. An electrical equipment's defense against lightning strikes is provided by a lighting arrestor. The arrester should be placed as near to the transformer as feasible for optimal protection. In order to restrict the installation of arresters to safeguard equipment, the maximum distance for arrester installation must be established. This study only looks at one 60 MVA transformer in the Surabaya Barat Main Substation, and its goal is to determine the minimum amount of error in transformer protection. Based on the maximum possible surge arrester surge arrester jarak with a power transformer at the Surabaya Barat Main Substation, the maximum possible surge arrester distance is 8,135 meters. Based on surge arrester capability, the transformer may be protected from over voltage since the maximum voltage that can occur is just 150.83 kV, with the maximum voltage remaining below the transverse impulse drop of around 650 kV.

Pemeriksaan Serta Pemeliharaan Pada Rel 1 Bay Saketi

This research aims to find out about the main substation, good rails (busbars) in the substation system, and inspection and maintenance of the 1 bay Saketi rail. The place and time for industrial practice is carried out at PT. PLN Persero ULTG Rangkasbitung Jl. Rawasari, West Rangkasbitung, District. Rangkasbitung District. Lebak, Banten Province. The implementation time is from 28 November to 28 December 2022 with 5 working days. In this research it was found that rails (busbars) require protection if used in open areas. This avoids a short circuit if a metal object falls on the positive or negative busbar. At one substation there are several types of busbar configurations, including: (1) single bus; (2) double bus-double breaker; (3) main and transfer buses; (4) double bus-single breaker; (5) ring bus; and (6) break and a half.

ANALISIS PEMASANGAN TRANSFORMATOR SISIP UNTUK MENGATASI TRAFO PSG.039 OVERLOAD PENYULANG MG.07 DI ULP MATANG GELUMPANG DUA

The MG.07 Substation in Matang Gelumpang Dua is located in the PT. PLN (Persero) Customer Service Unit Matang Gelumpang Dua Area Bireun, supplied by the Bireun Main Substation with a feeder capacity of 280 A. The MG.07 feeder supplies transformer PSG.039, loaded at 103.4% of its 250 kVA capacity. The standard load for a transformer is 80% of its capacity. The solution to address this issue is to install an insert transformer to distribute the load from PSG.039. According to data from PT. PLN (Persero) Area Bireun in 2023, the annual increase in electricity usage in Matang Gelumpang Dua Bireun is 8.3%. Therefore, using a 250 kVA insert transformer with an initial loading percentage of 26.8%, it will be able to accommodate the increase in electricity usage for the next five years, with a total loading percentage after five years of 68.3%.

BASSAMI Mohammed, ADRIAUCH Amine, BENKACEM Mariem, AZZIOUAZ Fatima, MIMOUNI Hicham, RKAIN Ilham (2024), Mandibular Mass Revealing Vesicular Thyroid Carcinoma A Case Report. International Journal of Innovative Science and Research Technology (IJISRT) IJISRT24MAY099, 188-192. DOI: 10.38124/ijisrt/IJISRT24MAY099. https://www.ijisrt.com/mandibular-mass-revealing-vesicular-thyroid-carcinoma-a-case-report

Fault is a regular incidence on distribution power system because distribution lines are always exposed to the environment with high probability of fault occurrence which when it happens, can cause hazardous conditions, equipment failures, power instability, huge financial loss and other forms of setback. In order to avoid these setbacks, it is necessary to detect and locate the fault on the network as fast as possible so as to prevent power system damages and reduce system downtime. This research study designed a smart fault location system model that detected and located ground faults at the point of occurrence using a developed 33 kV Ubulu-Uku radial distribution system as a test feeder and then formulated fault location equations which resulted into one single equation for all ground fault types on the network. The designed algorithm was evaluated on MATLAB 2023a environment using different line impedances of 0.01 Ω, 0.15 Ω, 0.35 Ω, 0.50 Ω, and 0.65 Ω which produced various ground faults located along path 6 section 17, path 8 secAtion 21, path 8 section 21, path 4 section 12 and path 8 section 21 with distance of fault from the main substation obtained at 3.51 km, 3.93 km, 4.03 km, 4.81 km, and 4.21 km. The results presented show performance of the designed algorithm and can be encouraged for practical implementation with promising result which will achieve some benefits like precise fault location information analysis, reduce the overall response time spent by maintenance crew to locate fault and reduce cost of operational maintenance and supply interruptions.

Evaluation of Kenten Main Substation Grounding System Based on IEEE 80-2013

Grounding system in a Substation has an important role in human and equipment safety therefore the grounding system condition should always be under observation. Maintenance and evaluation regularly should be carried out in line with the possibility of fault current increasing that embark in the system and disturbances from lightning strokes. In this study, the grounding system at the Kenten substation was analysed by using an analytic calculation method and a numerical method software. The calculation was based on IEEE Std. 80-2013 (IEEE Guide for Safety in AC Substations Grounding). From the study, it was obtained that the grounding system of Kenten substation just fulfils the safety standard regulation.

Evaluation of Distribution Transformer Placement Optimal Based on Load Balance

The distribution system is divided into primary and secondary distribution networks. The primary distribution network is the network from the main substation transformer (GI) to the distribution substation, while the secondary is the channel network from the distribution substation transformer to the consumer or load. The primary distribution network is better known as the medium voltage network (JTM 20kV) while the secondary distribution is the low voltage network (JTR 220/380V). The distribution network is the part of the electric power system that is closest to customers or loads compared to the transmission network. Currently, network electricity conditions throughout Indonesia are experiencing a decline of 5% which is due to various factors such as the medium-scale diameter of the conductors used, so at the farthest SR the value of overvoltage is 10%, the allowable voltage drop and must anticipate an increase in electrical load of 22.7 %, the placement of the transformer is not optimal and the distance the electrical energy travels from the transformer to the load is not paid enough attention so that the capacity of a transformer is not optimal and the voltage drop is also greater. Given these conditions, re-evaluation and planning is needed that takes into account planning criteria such as allowable voltage drops and continuity of electricity services so that optimization of the network used can emerge.

Predictive Maintenance for Electrical Substation Components Using K-Means Clustering: A Case Study

PT PLN (Persero) UP2D Kalselteng aims to provide reliable electricity supply, necessitating effective substation maintenance. This study proposes a predictive maintenance approach using K-means clustering on electrical current performance data from eight components in the Amuntai main electrical substation. The data undergoes preprocessing, including mapping to absolute z-scores to address electricity fluctuations. The K-means algorithm clusters performances, and models are evaluated using Silhouette scores. Results indicate the potential for predicting maintenance needs, as clusters align with real power outage data. The proposed method provides a proactive strategy for substation maintenance, enhancing system reliability. Feature combination experiments reveal that individual models for transformers and feeders are optimal. Hyperparameter tuning refines models, showcasing silhouette scores above 0.5, indicative of high-quality clusters. Comparisons with real-world power outage data validate the model's capability to identify anomalies, reinforcing the feasibility of the predictive maintenance approach. While the study demonstrates promise, on-field implementation and additional experiments are crucial for comprehensive validation and refinement of the predictive maintenance models.

Train-earth-grid coupling DC magnetic bias model for stray current diffusion

The DC magnetic bias phenomenon in transformers can result in increased noise and harmonic components. This study focuses on the DC magnetic bias generated by stray currents in the DC traction power supply system of neutral grounding transformers under multiple train operation conditions. A two-layer soil model is utilized to calculate geodetic potential, with rail potentials from both mainline and depot serving as sources for stray current within the model. Two paths of stray current intrusion into the transformer via the grounding network and cable armor layer from the Main substation have been modeled and analyzed. A simulation test has been designed to verify that the maximum error between experimental data and model calculation data is 8.87%. The implementation of a blocking connection device between the depot and mainline, as well as a change in grounding strategy for the metal protective layer, can effectively reduce DC bias magnetic current in the substation.

Analisa Relay Jarak Pada Saluran Transmisi 150 Kv Pada Gardu Induk Sekarputih Ke Gardu Induk Balongbendo

In the electric power system it does not always run normally. There are many disturbances or disturbance anomalies that can disrupt the operation of the system. One of them is at the Sekarputih main substation. last two years, the channel has experienced five short- circuit disruptions. As a result, electromagnetic distance relays must be replaced with digital distance relays equipped with reclosers. The reclosers will function when there is a relay disturbance on a trip and automatically reconnect. The disruptions may occur due to damage brought by unstable weather conditions. Indirectly, the value of relay settings will change and deviate from the PLN (state electricity company) standards. Therefore, relay re-setting was performed using two methods: the Fuzzy Mamdhani and the ANFIS methods. Using the Fuzzy Mamdhani method, the relay distance settings were as follows: Zone 1 = 0.523 Ω, Zone 2 = 0.54 Ω, and Zone 3 = 1.58 Ω. Meanwhile, the relay distance settings by the ANFIS method were: Zone 1 = 0.432 Ω, Zone 2 = 0.65 Ω, and Zone 3 = 1.22 Ω. The previous values of relay distance settings by PLN were Zone 1 = 0.587 Ω, Zone 2 = 1.046 Ω, and Zone 3 = 1.766 Ω.

Regenerative Braking Energy Utilization Analysis in AC/DC Railway Power Supply System With Energy Feedback Systems

In the power supply system with energy feedback system (EFS)s, the energy from EFS (WF) will flow to rectifiers, which is circulation flow (CF). However, the efficiency of CF between substations has been rarely studied. Besides, the relationship between the train operation and regenerative braking energy (RBE) utilizing efficiency is not clear. In this paper, the energy flow structure of the AC/DC railway power supply system including CF is established. In the double-train system, promoting CF when the trains’ distance is long can be beneficial to power utilization efficiency. Chengdu Metro Line 9 is analyzed as the multi-train system based on the iterative AC/DC power flow algorithm. The key to energy saving includes reducing the energy consumption of on-board resistance and the DC traction network loss. Compared with the catenary and rail system, the fourth-rail system can promote system energy efficiency by 23.5% at most. The CF and energy fed to main substations counts for less than 2% and 8% of WF. When the headway time is short, RBE should be avoided feedback to EFS, while the feedback power of EFS should be advocated when the headway time is long. The results can help guide the operation of urban rail to save energy.

Pengaruh Panjang Jaringan Terhadap Drop Tegangan Pada Penyulang Duku dan Kurma PT. PLN (Persero) ULP Rumbia

Voltage drops in distribution systems can occur in medium voltage networks (JTM), distribution transformers, low voltage networks (JTR) and house lines. Voltage drops in the network cause suboptimal distribution and increase power losses. PT. PLN (Persero) ULP Rumbia has two feeders with pure radial network characteristics sourced from the Seputih Banyak Main Substation. The length of the Duku Feeder network has a voltage of 96.8 KMS with a load of 150 A while the length of the Kurma Feeder network is 207.21 kV with a load of 155 A. The network reconfiguration of the Dente Teladas Substation was carried out to shorten the network length. This research aims to calculate the voltage drop that occurs at the Duku and Kurma feeders before and after network configuration. This research uses the quantity method to compare the calculation results with the voltage drop standards set by PT. PLN (Persero). After reconfiguring the Duku and Kurma feeders, there was an increase in tip voltage which indicated improvement. From the calculation results before adding the network to the Duku feeder, the voltage at the receiving end was 19.5 kV with a voltage drop of 7.1%, and at the Kurma feeder the voltage at the end of the line was 17 kV with a voltage drop of 19%. This is clearly no longer in accordance with the local TMP, and requires further study to overcome this problem. The voltage on the two feeders goes through a step up process using a Medium Voltage OLTC (On Load Tap Changer) so that the voltage on each feeder becomes between 19.86 kV to 20.16 kV.

CONTROL OF VOLTAGE MODES AS A MEANS OF LOAD REGULATION

The article substantiates the regulation of power consumption modes of production facilities due to the management of voltage modes in the power supply system. It is shown that the regulation of electricity consumption with the help of consumers - regulators (CR) is quite often associated with losses that occur when the CR is turned off. Studies have shown that the management of voltage modes in the power supply system, which affects its level, can play a positive role in increasing the efficiency of the optimization of power consumption modes. It is shown that a comprehensive solution to the problem of power consumption management is expedient both at the expense of CR control and the influence on the voltage regimes of the power supply system. It is shown that the regulating effect of the load is characterized by static characteristics. Solving the problem of forming static characteristics is possible in two ways: through active experiments and based on the integration of static characteristics of individual consumers. Experimental studies were conducted to identify the static characteristics of the load. Experiments were carried out on transformers of the main step-down substation of the chemical industry enterprise, equipped with on-load tap-changers. Experimental static characteristics with linear changes are constructed. The parameters of the model are determined by the method of least squares. Constructed experimental and analytical static characteristics. The voltage mode control procedure for load regulation is implemented in the power consumption control system.

Reliability Comparison of Rural & Urban LVDS Networks with Corresponding HVDS Networks Including Substation Reliability

This paper mainly determines the comparison of reliability of an existing rural area & urban area LVDS (low voltage distribution system) with their respective proposed high voltage distribution system (HVDS) and also including their 33/11 kV Substation. Ring main substation and single bus bar substation configuration are considered for urban and rural distribution systems respectively. The reliability of ring bus substation used in urban area is more as compared to single bus substation used in rural area. The load point reliability indices are calculated considering both substation reliability indices and radial feeder indices. The substation failure rate is calculated by considering overlapping outages approach and whereas the radial feeder indices are calculated by using cut set approach. Further, the LVDS Network is converted into the HVDS Network by replacing a high rating distribution transformer (DTR) supplying to a group of customers with Large in number with multiple small rating distribution transformers near to consumer terminals with less number of customers in each group. This conversion leads to Minimum length of LT Lines in HVDS Which results in improving voltage profile, reliability and efficiency. In this paper the disconnecting switches and alternative supply are also considered on both LVDS and HVDS Networks in the calculation of the reliability of to assess the reliability of the radial distribution system (FMEA)Failure mode effect analysis is used. This study uses a LVDS and HVDS system, and uses an alternative power source and disconnectors, to determine reliability indices of the rural area network and urban area network distribution system. In this paper the important distribution reliability indices to reduce system average interruption durations (SAIDI), Energy Not Supplied (ENS) and ASAI for LVDS and corresponding HVDS are calculated. The research idea is proposed on a Indian practical networks.

A new data mining strategy for performance evaluation of a shared energy recovery system integrated with data centres and district heating networks

This study presents a new data mining strategy to discover the performance and operational patterns of a shared energy recovery (SER) system with a data centre and a district heating network. Multidimensional clustering incorporated with a composite performance metric was first used to evaluate the typical performance of the system and reveal the interactions among different performance indicators. Decision tree analysis was then used to identify distinct system performances under different external conditions. Temporal clustering analysis was lastly used to identify the impact of recovered waste heat on the variations in heat supply from the district heating substation. The strategy was evaluated through a case study SER system at a university campus located in Norway. It was found that the most frequent performance accounted for 34 % of the total operational period with the instantaneous waste heat recovery rate of 572.9 kW, the temperature of waste heat of 57.2 °C, and the coefficient of performance of the heat pumps of 2.0. The outdoor air temperature and supply water temperature from the main district heating substation to the campus buildings showed a significant impact on the SER system performance. Moreover, the results showed that the SER system can help reduce the energy use of the district heating networks while increasing the fluctuations of heat supply from the main district heating substation.

Strategic Sizing and Placement of Distributed Generation in Radial Distributed Networks Using Multiobjective PSO

Distributed generators (DGs) offer significant advantages to electric power systems, including improved system losses, stability, and reduced losses. However, realizing these benefits necessitates optimal DG site selection and sizing. This study proposes a traditional multiobjective particle swarm optimization (PSO) approach to determine the optimal location and size of renewable energy-based DGs (wind and solar) on the Namibian distribution system. The aim is to enhance voltage profiles and minimize power losses and total DG cost. Probabilistic models are employed to account for the random nature of wind speeds and solar irradiances. This is used in an algorithm which eventually optimizes the siting and sizing of DGs using the nearest main substation as reference. The proposed method is tested on the Vhungu-Vhungu 11 kV distribution network in Namibia. Four cases were considered: base case with no DG, solar power, wind power, and a hybrid of both wind and solar. Optimal values for each case are determined and analyzed: 0.69.93 kW at 26 km for solar PV-based DG and 100 kW at 42 km for wind-based DG. These findings will serve as a valuable blueprint for future DG connections on the Namibian distribution network, providing guidance for optimizing system performance.

Feature selection algorithm for substation main equipment defect text mining based on natural language processing

AbstractThe dimension of relevant text feature space and feature weight of substation main equipment defect information is high, so it is difficult to accurately select mining features. The Natural Language Processing (NLP) medium and short‐term neural network model is used to realise the defect information text feature word segmentation in the log. After extracting the text features of defect information of main substation equipment with high categories to form the feature space; the TF‐IDF algorithm is designed to calculate the importance weight of text keywords, judge the criticality of defect information text feature vocabulary, accurately locate defect information text features, and realise defect information text feature mining. Experiments show that the algorithm has high precision for specific word segmentation of massive substation main equipment log information.