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Due to geographical locations of Indonesia, some technology such as hydro and solar photovoltaics are very attractive to be used and developed. Distribution Energy Resources (DER) is the appropriate schemes implemented to achieve optimal operation respecting the location and capacity of the plant. The Gorontalo sub-system network was chosen as a case study considering both of micro-hydro and PV as contributed to supply the grid. The needs of a smart electrical system are required to improve reliability, power quality, and adaptation to any circumstances during DER application. While the topology was changing over time, intermittent of DER output and bidirectional power flow can be overcome with smart grid systems. In this study, an automation algorithm has been conducted to aid the engineers in solving the protection problems caused by DER implementation. The Protection Security Assessment (PSA) method is used to evaluate the state of the protection system. Determine the relay settings using an adaptive rule-based method on expert systems. The application with a Graphical User Interface (GUI) has been developed to make user easier to get the specific relay settings and locations which are sensitive, fast, reliable, and selective.

Plug-in Hybrid Electric Vehicle (PHEV) have been widely used today. Grid to Vehicle (G2V) and Vehicle to Grid (V2G) will be the main challenge of the future smart networks with the increasing population of electric vehicles (EVs). Apart from all the advantages of massive use of electric vehicles, this can cause some problems in the electricity network system, such as the reliability and power quality of the distribution network system. For instance, when the battery charging takes place, the transformer may become overloaded, and another problem such as faster aging of a transformer may occur. Utilization of PV in charging station (SPKLU) or parking lot (PVP) of electric vehicles may become a solution. Another possible solution is to separate the general load or customers from the electric vehicle loads through additional utility transformers, so that the reliability and power quality of general customers will not be impacted by the electric car battery charging activity. In this research, the combined effects of EVs and PVP on the loading and aging of utility transformers are examined based on IEEE Std C57.91-1995. EVs load profile is modeled with monte carlo simulations and tested on a distribution system with 4 different scenarios. It was obtained that the use of PVP and the separation of EVs and general loads may improve the reliability and quality of the distribution network system and maintain transformer lifetime.

In the near future, Indonesian electric power systems will be strongly influenced by the penetration of Distributed Generation (DG) along with increasing electricity demand. This growth may cause capacity congestion, which is traditionally responded with new infrastructure investment by the utility. Alternatively, investment of DG has the potential to defer traditional investment. It also comes with some technical benefits. In distribution network planning, the suitable of investment decision must fulfil the economic (funding risk) and reliability (operational risk) criteria. Planning engineers have to deal with uncertainty of demand increase, financial risk, and ways to determine the timing, location, size and types of investment. This paper introduces DG (both non-renewable and renewable) benefits as an option to defer traditional investment using Real Option Analysis in radial distribution network. This combines two economical approach: Return per Risk Index (RRI) and Real Option Value (ROV). The uncertain conditions are simulated with Monte Carlo. Furthermore, the optimal power flow gives an assessment of the best investment option using DIgSILENT. It is found that RRI and ROV of gas internal combustion engine (ICE) power plant investment is higher (least risky investment) compared to Battery Energy Storage System (BESS) and traditional investment, respectively. This paper has shown that Real Option Analysis may provide flexibility options (pictured in decision tree and decision area) for utility in order to make decision on future investment, including the deferral of traditional investment while obtaining technical benefits as DG penetration impact as well.

The need for electricity rapidly grows in Northern Maluku. Meanwhile, the variation of power plants is still limited. This limited variation of primary energy source yields the domination of diesel power plant in Maluku Utara power systems. If this condition continues for a long period, high cost and high carbon emission as a dominant effect of diesel power plant utility become inevitable. Energy trilemma concept may be employed for comprehensive assessment to minimize diesel power plant domination and encourage optimized use of renewable energy potential. Energy trilemma will justify the renewable energy use. It covers three aspects at once: energy security, energy equity, and environmental sustainability. Energy Trilemma calculates a score incorporating several scenarios which clarifies optimized use of renewable energy potential that may help eliminate the diesel power plant domination.

Frequency oscillations in power systems may occur due to sudden load change or system disturbance. Such oscillations may result in unsynchronized and undamped signals. In a multi machine system where all generators must operate in synchronism, undamped oscillations may lead to instability. To overcome this issue, this paper proposes a damping control scheme consisting of Superconducting Magnetic Energy Storage (SMES) and Proportional Integral Differential (PID) controller to effectively damp frequency oscillations in multi-machine systems. Control parameters of the proposed SMES-PID system are tuned using Particle Swarm Optimization (PSO) algorithm. Simulation results reveal the effectiveness of the proposed controller in damping the frequency oscillations and maintain system dynamic and transient stability during various disturbance events. It is shown the design can find better quality solution in minimizing overshoot at frequency variations up to 78 % and accelerating the settling time up to 67 %.

The interconnection system faces inter-area oscillation challenges that affect power system stability. Conventional Power System Stabilizer (PSS) cannot provide effective damping to the inter-area oscillations. This paper deals with a Proportional Integral (PI) controller as a damping control scheme of the Unified Power Flow Controller (UPFC) to improve the damping of inter-area oscillation in a multimachine system. The proposed PI Controller-based UPFC is tuned using the Firefly Algorithm (FA), and the performance is compared with PSS. Simulation results show that the proposed PI Controller-based UPFC provides a better stability margin than PSS under the different conditions and effectively reduces the overshoot by 53%, accelerating the settling time by 74%, and minimizing the area graph by 85%.

Most of the blackout occurrences are caused by non-credible contingency events and often, the response to these situations is not prepared. One of such contingency event is the violation of transmission line limits leading to the disconnection of multiple highly loaded transmission lines. To prevent this event, knowing the loadability of the transmission line is important. In this research, a method to obtain the loadability of the transmission line is proposed. The data from the phasor measurement units are utilized to obtain the characteristics of the transmission lines (i.e. reactance, voltage drop pattern). Then, the loadability of the transmission lines in terms of thermal, voltage drop, and stability limits are calculated. The adaptive remedial action scheme (RAS) is also designed to maintain power transfer within a safe limit by load shedding and/or generation rejection. This scheme will update the total amount of load shedding or generation rejection and select the target based on the sensitivity of voltage to active power change. The method is applied to the Java-Bali system, in which a high amount of power is transferred from eastern to the western part through the transmission lines at the north and south corridors and hence, knowing the loadability limits of each corridor is important. Using the proposed method, the separation of western and eastern Java could be effectively prevented.

Typically, Diesel Power Plant system or Hybrid PV/Diesel/Battery Power Plants serve off-grid commercial loads in Indonesia. Diesel Power Plants contribute strongly to high cost whereas Hybrid PV/Diesel/Battery Power Plants still have rather uneconomic cost, intermittent power supply and capacity shortage. To overcome this issue, the concept of renewable energy power plant with firm capacity and stable operation or abbreviated as Refirmable Power Plant comes to handle through three-specific features: diesel-free, firm capacity, and stable operation. The redundant operation of solar photovoltaic, battery energy storage system and fuel cell power plant may serve load demand for economical cost without any interruptions. HOMER software simulations for three peak load scenarios: 150 kW, 1000 kW and 2000 kW show that Refirmable Power Plant can serve load demand without any capacity shortage on Levelized Cost of Energy (LCOE) about USD 13,4 cents–19,5 cents. This result may drive renewable energy development in Indonesia to shift from Conventional Hybrid Power Plant to Refirmable Power Plant for serving off-grid commercial load.

The partial shading of photovoltaic (PV) modules due to clouds or blocking objects, such as buildings or tree leaves, is a common problem for photovoltaic systems. To address this, maximum power point tracking (MPPT) is implemented to find the global maximum power point (GMPP). In this paper, a new hybrid MPPT is proposed that combines a modified grasshopper optimization algorithm (GOA) with incremental conductance (IC). In the first stage, the proposed modified GOA is implemented to find a suitable tracking area where the GMPP is located. Then the system moves to the second stage by implementing IC to get the correct GMPP. IC is a fast-performing and reliable algorithm. By combining GOA and IC, the proposed method can find the GMPP accurately with a short tracking time. Various experimental results show that the proposed method yields the highest tracking efficiency and lowest tracking time compared to some of the state-of-the-art MPPT algorithms, such as particle swarm and modified firefly optimizations.

Distribution networks with high electric vehicle (EV) penetration levels can experience transformer overloading and voltage instability issues. A charge scheduling approach is proposed to mitigate against these issues that suits smart home settings in residential areas. It comprises measurement systems located at distribution transformers that communicate directly with fuzzy logic controller (FLC) systems embedded within EV supply equipment (EVSE). This realizes a reduction in data processing requirements compared to more centralized control approaches, which is advantageous for distribution networks with large numbers of transformers and EV scheduling requests. A case study employing the proposed approach is presented. Realistic driver behavior patterns, EV types, and multivariate probabilistic modeling were used to estimate EV charging demands, daily travel mileage, and plug-in times. A Monte Carlo simulation approach was developed to obtain EV charging loads. The effectiveness of mitigation in terms of reducing distribution transformer peak load levels and losses, as well as improving voltage stability is demonstrated for a distribution network in Jakarta, Indonesia.

Modern power systems have evolved, from classical type of synchronous generation to more distributed non-synchronous generation with power electronic-based, some country is dealing with high penetration of renewable energy sources (RESs) such as photovoltaic and wind turbines. However, this new generation model does not have natural inertia and damping properties, which is a classic feature of synchronous machines. The lack of system inertia in such power system has mainly two implications on system frequency stability, namely: higher frequency deviations (nadirs/zeniths); and larger ROCOF, which results in possible tripping of grid components. Many researchers have shown how to use inverters and energy storages with synthetic inertia control algorithms; by then, it will be recognized as synchronous generators by power grids, maintain and improve frequency stability. This paper aims to show the process of identifying the optimal placement of energy storage with SIC in order to improve frequency stability in a high RESs penetration power system using Mean-Variance Mapping Optimization (MVMO) algorithm.

Indonesia is going to enter the new era of electric vehicle. In this paper, the charging load of electric vehicles (EVs) is presented along with the operational cost optimization of the distribution grid based on the trend and the development of EVs in Indonesia from 2020 until 2030. Since the development of EVs in Indonesia has just officially begun, the charging loads and demand data from several types of EVs are analyzed. With no historical data for Jakarta, Monte Carlo simulation method is proposed with 3 main scenarios for forecasting the charging load of EVs, which are reference, moderate and advanced scenario. Operational cost optimization approach is proposed in order to achieve the most preferable pricing scheme for EV charging load in the distribution network. Accordingly, the optimization will be made based on the 3 main scenarios used in the forecasting process. As a study case, Jakarta City is chosen as the main object to analyze the best pricing strategy of the development of EVs throughout 2030 as its debut to start the electric transportation era.

Borneo is one of Island in Indonesia besides Sumatera, Sulawesi, Java, and Papua. It has three subsystems, West Borneo, East - North Borneo, and South - Center Borneo. There are a lot of option to increase the power, one of the solutions is transferring the power between subsystems. This paper will expain the study of interconnecting two subsystemss, East - North Borneo with South - Center Borneo with the impacts to the system. Nowadays, that two subsystems is weak, which total generation of East – North Borneo is 400 MW and the South - Center Borneo is 500 MW, both of the subsystems has limited spinning reserved (10%), the spread of the load is not evenly converging in some area with long distance transmission and there is only one generation as the base load carrier for each subsystem. In 2015, the developing of electric generation in South - Center Borneo will be growth rapidly than East - North Borneo, whereas the load itself lighter. So there is a planning to interconnect between two subsystems to get realiblity and economical value, because of some diesel generation that was full of fuel will be switched off. This stability study includes power flow, voltage stability, small signal stability and transient stability. This study uses power system simulation software Digsilent. The output of the study is a technical recommendation for The headquarter of state electricity company as a policy taker about this interconnecting plan.

Power quality and voltage stability are the main indicators of customer satisfaction because it influences business operations. Based on the results of the 2016 customer satisfaction survey by Markplus.inc, some industrial customers complain of voltage stability, especially related to dip voltage. Industrial customers complained about this dip voltage due to the loss of the company's operational tools. Dip voltage is a problem that must be resolved by industrial customers and electric utility companies. For electric utility companies, dip voltage greatly affects the sale of electricity that is not optimal because the dip voltage has an impact on the operation failure in industrial machinery. In addition, the dip voltage also has a negative effect on the service image of the electric utility company on the priority customer side. For this reason, the voltage dip needs to be handled seriously. According to IEEE 1159-1995, Dip voltage of 20 kV is a decrease in AC voltage of 2 kV up to 18 kV for 0.01 seconds until 60 seconds (for a frequency of 50 Hz). This dip voltage is caused by lightning, network interference, the effect of switching, motor operation, and sudden load changes. Dip voltage causes a huge financial impact on industrial consumers. In this paper, a dip voltage case study will be evaluated at The Food and Beverage Industry in East Java. The financial loss of industrial customers reaches 328,000 USD or 4.7 billion Rupiah in one dip voltage event. This is because customers have suffered a production failure so they have to restart their production process. They also have to dispose of large quantities of raw materials due to product failure due to the dip voltage. For this reason, it is necessary to formulate a proposed management model in solving this dip voltage problem. This paper also offers proposed steps that can be taken by electric utility companies in suppressing the amount of dip voltage so that the electricity supply becomes more qualified. In accordance with the evaluation of priority and risk management matrices, the results show that the steps are appropriate and can be implemented in reducing the number of dip voltages.

In general, the design of coal-fired power plants is not designed under flexible operating conditions. This flexibility will potentially cause changes in the operating pattern of coal-fired power plants, which operate at a minimum load. This pattern of operation will lead to increased use of coal, reduce the value of thermal efficiency, and possibly reduce equipment reliability. This paper presents an analysis of the impact of the flexibility of the coal-fired plant operation on its reliability. The solution that we propose in this paper is to integrate the coal-fired plant with Battery Energy Storage (BES). On scheme, the battery will be charged in a off-peak and will be discharged when a peak-load. We present several choices of BES in this paper, to find out more about this integration. in part 1 this will focus on how the impact of integration of coal power plants with battery energy storage in terms of heat rate levels, analysis is based on the effects of changes in heat rate levels of coal power plants during the use of BES and compared when not using BES.

Nowadays, network operations, including in low voltage systems, are becoming more complex. There is a necessity to monitor the systems which could be realized using the data gathered by the smart meters. This monitoring task can be accomplished through state estimation analysis. It is hence necessary to study some factors that affect the state estimation analysis. In distribution system analysis, the unbalanced parameters of the feeders are mostly simplified with sequence networks. Shunt capacitances and grounding methods are commonly neglected. Furthermore, errors and uncertainty in measurements and power system parameters may exist. Such simplifications and imperfections are likely to affect the results of the analysis. This work covers the abovementioned issues and assesses their impact to estimation results. An AC state estimation algorithm was created in AMPL. Extensive simulations have uncovered some findings in order to obtain satisfactory state estimation in low voltage networks.

The power quality problems such as voltage sag are a great concern to consumers, especially for industrial consumers. Most modern industrial equipment is quite sensitive to instantaneous voltage sags, so it is necessary to keep the power quality to guarantee the reliability of the production process. The Dynamic Voltage Restorer (DVR) with Battery Energy Storage System (BESS) has been applied as one of the representative devices for compensating the voltage sags. This paper proposes a multiloop PR control based an integrated BESS-DVR, which is organized in the stationary reference frame, to mitigate the power quality problems such as the unbalanced voltage sag, deep voltage sag, and phase jump. The advantages of the proposed multiloop controller provide the rapid response to the disturbance on the grid to track the sinusoidal reference, while the configuration is simpler than the PI controller. In this paper, the design of the proposed controller is explained in detail, and the simulation results of comparative studies with the PI controller in the synchronous reference frame are described. The proposed model of an integrated BESS-DVR system and the control algorithm are validated by PSiM simulation under various voltage disturbances such as unbalanced and balanced voltage sag.

Indonesia, which is represented by PLN as stated- owned electric utility company, commits to increase the share of renewable energy mix up to 23% in 2025. One way to reach this goal is the commitment to solar power generation. However, generation from photovoltaic has intermittency that dependent on sun irradiation, so the stability of power system might be affected in certain cases. The stability problem can be anticipated by using a hybrid power system with the composition of photovoltaic, battery, and diesel. Optimal power flow and N-1 contingency simulation is conducted to determine and compare locations and the capacity of hybrid power system. Furthermore the composition of hybrid power system is evaluated by an frequency stability simulation and the LCOE is calculated. The appropriate hybrid power system is selected by applying a knapsack dynamic programming approach. The result of the calculation is the optimal location of the hybrid power system with photovoltaic capacity as planned. This method is applied to Sumbawa power system as a case study.

Indonesia state electric company (PLN) through the Electricity Business plan (RUPTL) 2018-2027 is targeted to realize 23% of energy mix on the renewable energy system. Photovoltaic (PV) is one of the alternative solutions considered due to its environmentally friendly energy and the trend of its price decline. However, PV penetration on the grid may affect the grid frequency stability due to their intermittency. Hence, in this paper, the cost-benefit analysis was conducted to calculate the amount of the PV penetration, and then, its impact on frequency stability is analyzed. The South-Central Kalimantan system is used as the study case. The simulations show that PV penetration reduced the NPC (Net Present Cost) and LCOE (Levelized Cost of Energy) of the system. Also, the system frequency deviation was affected by the size of the system load and PV capacity. To maintain the frequency according to the grid code of 49.5 Hz, the use of the battery is required in several scenarios.

The purpose of this study is to develop a method to determine spare transformer number and location. Using Markov Chain method, state transition model and steady state probability was used on each 500-kV substation in order to analyze the effect of spare number and location variation with the reliability changes. To give an actual result of the case study, calculation of spare transformer number and location on 500/150 kV transformers in Java Bali System was analyzed. The steady state probability results will vary depending on the number of spare transformer, these results can then be used to assess the spare transformer needed. The variation of spare transformer location can be used to analyze the best possible location of the spare in order to satisfy the reliability required. The methodology presented shows an integrated calculation for determining the spare transformer number and location.

Quality of a power system network can be evaluated from its voltage performance. There are several bus/substation of Java Bali networks that frequently operate in unsatisfied voltage level. As an important part of Indonesian electricity system, quality improvement of this network should be sustainably maintained. The occurring problem can be solved by reactive power compensation. Compensation can be done by installing reactive power compensator into the network. To get an optimal improvement level of voltage performance, the installation location of reactive power compensator must be carefully selected. The selection process can be done by consider the operating voltage, bus sensitivity factor, power angle sensitivity factor and geographic location factor on each location in the network. With consideration of these parameters then the optimal location and configuration of the reactive power compensator can be obtained.

Dynamics of connected balls floating on surface of fluid oscillating sinusoidally has reported. In this work a simple electrical generator is simply modeled based on the change of distance between connected balls from its initial value or Δl. By considering only one-dimensional motion of each ball, all the changes Δl are positive, that makes the system easier to be predicted. Sum of all Δl as function of initial initial distance between balls or l is discussed. Water wave wavelength λ is also varied to see how it influences the sum of all Δl.

Distribution system planning (DSP) aims to ensure, that the electricity distribution can satisfy the demand in an optimum way. It has to provide the necessary economical, reliable, and secure electricity to consumer. Network solutions of DSP are the solutions that need adding and/or replacing some network asset. Traditional response is a large investment that creates large capacity. Therefore there may be unused capacity for period years. Thus, there is excess system capacity after the investment is made. In other hand, the alternative responses frequently install distributed generation in very small size. Original plan can be deferred by installing distributed generation. Investment using distributed generation is an option to defer the larger investment in distribution planning. Utility can use this option to face the uncertainty in demand projection. This paper proposes model for determining decision area of distributed generation investment as deferral option in industrial distribution system planning. It uses real option valuation to define the boundary by using the critical value. This study depicts the decision area by 'discount rate'- 'electricity price on transmission' and 'discount rate' -'delaying time' boundary.

The operation of intermittent and non-dispatchable power plant in the system will affect the economic feasibility of existing power plants, as indicated by NPV, IRR, PP and BCR. The operation of Solar PV Farm which is one of the intermittent and non-dispatchable power plants, will change the dispatch of existing power plants followed by the capacity factor of the plants. Since the economic feasibility is a function of capacity factor, every change in dispatch will affects the economic feasibility. However, if the decrease in economic feasibility of existing power plants can be compensated by the system electricity production cost reduction, then the integration of Solar PV Farm is acceptable. The case study of research already done in Belitung System as one of the attractive systems for renewable energy in Indonesia.

Power quality problem in distribution system become more serious matter since the advancement in industrial equipment which require good power quality to ensure the sustainability of the production process. Voltage sag is one of the power quality problems that most probably happened caused by either normal or abnormal event in power system. Dynamic voltage restorer (DVR) can be chosen as a preferred approach to improve voltage quality at sensitive load locations. This paper proposes two control strategies to compensate the unbalanced voltage sag with enhance dq frame method with PI control and simplified αβ frame method with PR controller. The unbalanced voltage sag condition caused by single line ground fault (SLGF), which is most probably happened in distribution system, can be compensated well by these methods. Additional feature is coming from PR controller in αβ frame which plays an important role in performing better voltage tracking error, compared to PI controller in dq frame as an enhance comparison. PSIM simulation result has been presented to evaluate the effectiveness of the proposed method.

This paper discusses and compares three alternatives to reduce electrical energy consumption (kWh) and peak demand (kW) in buildings, namely deployment of rooftop solar PV, battery energy storage and HVAC set point adjustments. The building model of a warehouse located in Alexandria, VA, was developed in eQUEST, and its electrical consumption was validated with metered data. To perform the overall analysis, adjustment of HVAC set points was conducted in eQUEST, while Solar PV and battery models were developed and deployed on top of the developed eQUEST building model. Overall, the method presented here can serve as a guideline for building owners to analyze energy savings/peak demand reduction alternatives, of which benefits are varied from buildings to buildings based on building sizes, electricity tariffs, climate zones and building operation.

Integration of intermittent power plant into system will have a significant effect to the system. The intermittency of these renewable energy source will cause uncertainty in system operation. In small island, which is serve by small isolated system, defense scheme will set only to allow small change in system frequency. Transient stability, especially frequency stability of system is proposed methodology to determine maximum capacity of intermittent power plant which can penetrate such small isolated system. To strengthen the conclusion of the transient stability simulation is also carried out on the disturbance or fault condition. So, the maximum capacity of Solar PV can be connected to the system has a solid foundation.

Energy savings and occupant thermal comfort are the two most important factors in controlling heating ventilation and air conditioning (HVAC) operation in buildings. Typically, it is found that thermal comfort is not always met in buildings. Hence, there is still an opportunity to improve indoor thermal comfort, and at the same time save energy by controlling HVAC set points. The objective of this paper is to propose a method to obtain energy savings by adjusting HVAC set points based on occupant comfort measured using Predicted Mean Vote (PMV) and occupancy information. The idea is to calculate hourly PMV values based on real-time occupancy information, indoor temperature set points and humidity in a building. Then, a new set of temperature set points that can maintain occupant comfort, i.e., PMV = 0, is derived. To evaluate the effectiveness of the proposed method, a building model is developed in eQUEST using the information from a real-world building located in Alexandria, VA. Research findings indicate that HVAC electrical consumption savings of 14.58% is achieved when the proposed set point adjustment method is implemented as compared to that of the base case. To study the impact of adding occupancy information on HVAC energy savings, another scenario is simulated where HVAC set point is increased when the building is unoccupied, e.g., during lunchtime or holidays. Research findings indicate that additional HVAC electrical consumption savings of 8.79% is achieved when taking into account occupancy information in HVAC control.

Renewable energy surely become solution for environment-friendly generation in recent years. Despite that, it also poses stability problems for power system network. Strategies for Non-synchronous generation (NSG) to behave like synchronous generation could be one of several solutions made. This paper presented a model of Virtual Synchronous Machine (VSM) converter which is controlled by power electronic based approach. Simple 2 machines system chosen as the base study for frequency and transient stability. The study conducted using DIgSILENT Power Factory software to simulate the system response when 150 ms short circuit event and load event implementation. Parameter identification with least square method also presented to obtain better parameter of VSM. Better active power and frequency response during load change and short circuit event while VSM operates improved the system’s frequency and transient stability.

Electricity in rural area of Indonesia is mostly in small-scale with diesel generator as the main power source. These diesel generators are mostly in the latter stage of operational age, thus have limited capability and poor performance. Microgrid has been introduced lately, as a system to integrate more renewable energy sources to the existing power system. Photovoltaic (PV) source is one of the most popular renewable energy source which is utilized by microgrid. However, the fluctuating characteristic of microgrid operation and the intermittent characteristic of PV are making it harder for diesel generator to maintain the stability of the system. This situation might lead to further diesel generator performance degradation, causing operational and maintenance costs to rise. This research proposes a microgrid concept consisted of PV, diesel generator, and battery, aiming to minimize the impact for diesel generator caused by PV integration. Droop control is utilized to enable load sharing between diesel generator and PV source through grid-connected inverter. This scheme will enable the PV and inverter to participate in maintaining system operation and ease the operation of diesel generator. A battery energy storage system is introduced as a buffer to further enhancing system stability. It can be shown that under this scheme a microgrid with PV is able to actively participate in maintaining grid condition by sharing load with diesel generator, assisted by the battery as a buffer.

Regarding the intermittent nature of photovoltaic (PV) connected to grid, there will be a change in the operational mechanism. The energy generated from PV is highly dependent on the solar radiation. There are differences between using PV Farm from PLN (State-Owned Electricity Company) and IPP (Independent Power Plant). Modelling PV Farm from PLN implies the large cost of installation but little charge on operational. Meanwhile, there is no installation cost of PV Farm from IPP yet the operational price is far above PLN-PV Farm. Due to this modellings, IPP-PV Farm will increase total cost of generation. On the other hand, low operational price of PLN-PV Farm makes this power plant can compete well to generate power. Therefore, PLN-PV Farm will decrease total cost of generation. During daytime, dispatch of the other power plants existed before reduce as there is active power supply from On-Grid PV Farm. On technical side, distributed installation of PV Farm leads to higher voltages in the substations. The loading of the transmission system declines along with the reduced power transfer because there are additional supplies from PV Farm. The result of transient stability analysis indicates that when there are clouds covering solar radiation towards PV Farm, the frequency and voltage decrease but still within permissible limits.

Electrical energy obtained from state-owned electricity company is often can not fulfill the electrical energy required by the industry during peak load. Another problem that industry faced is the availability of electrical energy supply is not continuous. Solution to this problem, the industry needs another source of electrical energy so the availability of electrical energy can be achieved. This study presents the analysis of reliability improvement for 20 kV distribution system which connected to state-owned electricity company's Distributed Generation (DG) in Karawang Industrial Region. Analysis of this study is using DG with new and renewable energy sources, solar panel and batteries systems, it is aimed to increase the reliability of each load (industry) and determines the cost to build the DG. The reliability calculation is done by using DigSILENT software both before and after the DG installation. Calculation analysis of solar panel system's components is calculated using Microsoft Excel software. Followed by calculating Levelized Cost of Energy (LCOE) as a value indicating the cost required to generate power per kWh so we can determine the selling price per kWh by state-owned electricity company for the Industry in order to fulfill the DG development cost.

Belitung island will be developed as one of tourism economic zone. Regarding to this situation, the electricity will increase the capability of supply by using non fossil fuel power generation. Integration of intermittent renewable energy such as photovoltaic farm become a main concern in this development. This paper deal with a mechanism to calculate a maximum penetration of PV farm in the Belitung system without deterioration of existing defense scheme in the system. The calculation includes the transient effect the cloud movement toward photovoltaic farm. Beside the calculation of PV power plant, there is also the simulation of biogas penetration in Belitung Power System. Biogas power plant capacity that available in Belitung is 9.5 MW. The mitigation to make the frequency deviation smoother is also described.

Building occupancy information becomes important in term of indoor environmental quality, energy building simulation as well as energy consumption and energy saving approach. Occupancy estimation provides energy efficiency up to 50%. Occupancy estimation is strongly influenced by the characteristics of the building and the behavior of the occupants. This situation makes accurate occupancy estimation difficult. Several models to resolve the problem are reviewed in this article which includes approaches from the side of the sensing and processing method. Processing approach using statistical methods and machine learning. Previous recent research related to relevant models and applications in occupancy estimation is discussed. Further research prospects are proposed based on analysis of previous work.

STATCOM is reactive power compensator based upon a voltage source converter which uses power electronic devices with turn-off capability as switching devices. Its main function is to support bus voltage of which it is connected to the system by providing quick response to supply or absorb reactive power. For damping power oscillations purpose, it is required to employ power oscillation damping (POD) function wherein its output is summed to voltage reference as input of STATCOM. This paper focuses on implementing POD function in STATCOM control to damp interarea oscillations mode. Kundur's two area system with 11 buses and four generating units is used. Each generating unit uses fast exciter and the system presents three modes of oscillations, that is, local mode area 1, local mode area 2 and interarea mode. The power oscillations can then be damped by STATCOM Controller which is equipped with the POD function. The effectiveness of controller design is assessed based on time domain simulation using PSCAD software.

Voltage stability is a common issue in developing power system. It is mainly affected by reactive power balance in the system. If reactive power is not well planned and managed, there is possibility of occurrence of voltage instability in the system. One solution to prevent voltage instability in the system is by VAR compensation. In this work, new technique to determine the placement of different types of shunt VAR compensators based on sensitivity method is presented. Simultaneous planning of SVC and STATCOM placement is also conducted. Improvement in system stability is achieved using the method.

Event detection has an important role in detecting the switching of the state of the appliance in the residential environment. This paper proposed a robust smoothing method for cepstrum estimation using double smoothing i.e. the cepstrum smoothing and local linear regression method. The main problem is to reduce the variance of the home appliance peak signal. In the first step, the cepstrum smoothing method removed the unnecessary quefrency by applying a rectangular window to the cepstrum of the current signal. In the next step, the local regression smoothing weighted data points to be smoothed using robust least squares regression. The result of this research shows the variance of the peak signal is decreased and has a good performance with better accuracy. In noise enviromment, performance prediction quite good with values greater than 0.6 and relatively stable at values above 0.9 on SNR> 25 for single appliances. Furthermore, in multiple appliances, performance prediction quite good at SNR> 20 and begins to decrease in SNR 25.

Perkembangan sistem tenaga dalam pembuatan transmisi baru dan fasilitas pembangkitan sistem tenaga listrik telah dibebani lebih besar daripada biasanya. Sebagai konsekuensinya, banyak sistem tenaga yang mengalami permasalahan tegangan yang pada akhirnya akan memicu ketidakstabilan tegangan. Makalah ini membahas penempatan phasor measurement unit (PMU) dengan menggunakan integer linear programming untuk penentuan prediksi margin kestabilan tegangan ( voltage stability margin - VSM) dengan didasarkan pada pengukuran lokal yang memakai ekuivalen Thevenin untuk representasi sistem. Penempatan PMU dipilih sedemikian rupa dengan algoritme integer linear programming tersebut sehingga dapat ditentukan phasor tegangan dan arus pada setiap bus pada sistem tenaga listrik. Data-data yang diperoleh, berupa phasor tegangan dan arus pada setiap bus , dipakai untuk perhitungan prediksi margin kestabilan tegangan.

Jawa Bali 500 kV power system grid comprises of two large areas which are connected by two double circuit transmission lines. However, under high power transfer from east to west area on October 19, 2012 resulted in Jawa Bali power system experienced voltage drop until 0.86 pu in west area. Very low voltage may lead to voltage stability phenomenon. This paper would analyze maximum power transfer capability without and with introducing shunt compensators. Static analysis using P-V Curve method is aimed to assess voltage stability phenomenon. P-V Curve corresponds with total active power transfer (P) of two transmission lines connecting west and east area compared to voltage system (V) behavior in west area. The study also includes investigation of power transfer capability limit enhancement with use of shunt compensator compare to initial condition. Various options of shunt compensators considered are MSCs, SVC, and STATCOM. Power Transfer Stability Index and Q-V Curve sensitivity were considered to acquire list ranking location of shunt compensator. Based on static voltage analyses result, use of shunt compensators was proven to increase power transfer limit.

High short-circuit current and voltage excursion are two major great concerns for an electricity provider in Indonesia, named PLN. These two problems are mainly remarkable in Jakarta area, i.e., the central load of Jawa Bali system. In order to achieve both decrease in the short-circuit current and increase in the voltage level, Insertion of the intermediate 275 kV networks together with the change in the 150 kV networks from loop structure to radial structure is examined with several scenarios. Genetic Algorithm multi-objective optimization technique is also applied for selecting the 275/150 kV transformer reactance in terms of the aforementioned two requirements. The performance of each scenario is verified using the short circuit index, the voltage index and the number of installed 275 kV transmission lines and transformers. Three subsystems in Jakarta area which are Bekasi, Gandul and Kembangan are selected, because these subsystems include most of the issues related to the short-circuit current and the voltage level. The selected scenario successfully reduces the short-circuit currents and increases the voltage level in 150 kV system.

If the sizing of renewable energy power plant is planned with a less reliable data of its energy sources, usually in the future, the power system will have poor performance. Such cases often occur in various regions, including Indonesia. This problem can be solved through observation and measurement in the power systems using a data logger. Data logger is the electronic equipment which can record the formation of data accurately. In this paper, the current and voltage formation of solar-wind hybrid power system which is recorded by the data logger will be analyzed. The results then will be used for resizing strategy of the plant, especially which was established but still showed indications of inefficiency. Furthermore, by using the Levelized Cost of Electricity (LCOE), the system energy cost before and after resizing will be compared. The data logger is also used to see the capacity of the energy source by applying the indirect method.

This paper deals with a method to determine short-term loading estimation of inter-bus transformers based only a limited data of variables. A grey predicting approach is implemented in this paper to solve dynamic short term load forecasting affected by the climate changes in Indonesian EHV grid, as provided by Jawa Bali Control Center. A dynamic forecasting model is needed due to the uncertain nature of the load predicting process specifically when load changes is correlated with the external effect. Traditional GM (1,1) as basic model is presented to compare with the correlation inter-variable model in grey method for inter-bus loading transformers loading conditions refer to the temperature variation pattern during only the year 2009. GM(1,2) model denotes the correlation and relationship of hourly load demand affected to the 2 (two) tropical seasons, in this case by using local ambient temperature as dynamic variable. The daily load curve for Cawang and Cibatu distribution areas, as representing big local substations in Indonesia spatially, was used to validate the models. The model adequacy and weekly forecasting result had indicated a good and justified grade in error diagnostic checking (MAPE) in each location.

System failure cannot be avoided, one of the solutions to maintain system reliability is with the existence of spare equipment, and however the number of spare equipment will increase the investment costs. Currently, spare transformer calculation study only considers one criteria in state transition model, a new model which considers other criteria such as transformer condition and transformer loading is needed. Java Bali 500/150 kV Transformer case study was used in order to show the usefulness of the proposed model.

In the new paradigm, electric power system development should provide a negotiation space mechanism between all players with the objective function to maximize payoff distributed to each player in the system. Uncertainty risk and operate effectively and efficiently become a high consideration for all players in the decision making processes to select an investment and power system operation. This paper deals with simultaneous and desentralized with multiple objectives scenario within a global framework. The planning mechanism is prepared on the basis of cooperative game theory. Its coperative framework will encouraged an independently, distributed decision making in the competitive structure environtment. Main contributions of this paper are: a general model for power system planning in the form of cooperative game theory, and its time and spatial decomposition. This method will be implemented in Garver test system. Index Terms: power system planning, game theory, Shapley bilateral, coalition formation, static security

this paper present an analysis to determined 500/150 kV spare transformer in Java Bali System. To obtain the desired reliability value, the spare transformer failure rate is determined from the failure rate value. This study uses the method of Inventory Management to get the value of failure rate. Inventory Management and Pareto Law will analyze transformer data such as impedance and location get a classification of transformer. Pareto Law method determined which disturbance of transformer components are the major failure. The failure rate will be calculated using historical data and the classification above. Finally, the spare transformer calculation will be determined using several calculation as a benchmark, the favored calculation or method of this study is Markov Chain Method.

This paper proposes a control strategy for the distributed generation based on isolated system, which consists of diesel generator, photovoltaic (PV)generator and battery. The diesel generator is used being a main energy source, but the photovoltaic generation is chosen as an additional power source due to the growth of the load demand and for establishing an isolated microgrid. The control of microgrid is very important for making stable operation of electric system. In case maintaining the system performance in voltage and frequency, the droop control is used for the power sharing among the microgrid system. The proposed droop control consists of power control, voltage control, and current control. Simulation is done in Matlab/Simulink™ to demonstrate the effectiveness of the proposed control methods. Simulation resulted that the voltage and frequency of the system can be maintained when the photovoltaic and battery is added to the system. The proposed control can restored the voltage and frequency stability while the consuming load is changed to increasing or decreasing. Meanwhile the active power sharing can be dispatched each other between power sources.

Network reliability of distribution system is one of the key performance indices to be realized with many efforts. Installing Distribution Generation (DG) on radial distribution network closer to the customers is one of the efforts, which can improve the indices. This paper will present a GA method to determine the best location and capacity of DG placement with minimum power losses as an objective function to achieve optimum result. By DG placement in the network, except improve the voltage profile and power losses also the reliability indices such as SAIDI, SAIFI and EENS. Therefore the reliability will experience an improvement than before. For calculating and analyzing the reliability indices it uses ETAP 12.6 software which is separate analysis with determine the position and capacity optimization method. This concept will realize by simulating in the 132 bus radial distribution system and considering into two schemes, the base load scheme and full load scheme.

Reliability improvement is one of the important things for electrical distribution company. By using some devices such as recloser and sectionalizing switch will reduce the amount of interrupted load during the fault. However, improvement of reliability need a cost, it can be said that reliability of the system and investment cost is comparable. In this paper, reliability of distribution network is assessed by considering reliability cost worth. A methodology based on cost worth analysis for optimal switch placement in distribution system network is proposed. This paper study has been conducted on the existing of Indonesian radial electrical distribution network.

Indonesia is an archipelago country consisting of five major islands and scattered of approximately 17,000 smaller islands. It is also the fourth most populous country in the world and has relatively high energy demand, especially for electricity. The Java-Bali system is the largest electricity system and the highest electricity demand in Indonesia but with a scarce energy resource. Meanwhile, the Sumatra system has a lower electricity demand but an abundant of available energy resources. Thus, in order to increase the national electrification ratio and the power supply in Java-Bali system, a ± 500 kV high voltage direct current (HVDC) system will be operated in 2018 to transfer 3000 MW from Sumatra island to Java Island through 504 km dc transmission line (including 40 km sea-cable) by a conventional type, i.e. Line Commutated Converter (LCC). This 3000 MW is produced from 6×600 MW coal power plant located in South Sumatra. The rest of this power will be transmitted to the Sumatra System.

Single line to ground faults is a problem that most often occurs in extra high voltage overhead lines, and generally temporary. This type of disturbance can be quickly eliminated by using a single phase auto reclosures, but a secondary arc phenomenon often makes single phase auto reclosures in the extra high voltage overhead lines failed to work. This research aims to obtain a proper modeling of the secondary arc using ATPDraw. Secondary arc modeling has been successfully obtained and implemented in the Tasikmalaya-Depok extra high voltage overhead lines.