Pothisarn, Chaichan
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Preferred name
Pothisarn, Chaichan
Alternative Name
Pothisarn, C.
Main Affiliation
Email
chaichan.po@kmitl.ac.th
10 results
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Item type:Publication, Effects of Conditional Changes on High-Voltage Direct Current Transmission Line Characteristic(2022-01-01); ; - Some of the metrics are blocked by yourconsent settings
Item type:Publication, An Evaluation Study on Electric Appliance Characteristics and Load Patterns in Residential Buildings(2026-01-01); - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Transient Analysis to Distinguish Mechanically Switched Capacitors Using Discrete Wavelet Transform and Artificial Intelligence(2026-01-01); ; Capacitor banks are widely used in modern power systems for reactive power compensation and voltage regulation. However, switching operations of mechanically switched capacitors (MSCs) can generate transient phenomena, such as inrush currents, which may resemble fault currents and lead to misoperation of protection systems. Therefore, accurate detection and classification of transient events are essential for reliable system operation. This study proposes a hybrid approach for transient signal analysis and classification by integrating the discrete wavelet transform (DWT) with artificial intelligence (AI) techniques, including probabilistic neural networks and fuzzy inference systems (FIS). The DWT performs time–frequency analysis to extract multi-scale wavelet features from three-phase current signals. The proposed method enables both discrimination between inrush and fault currents and multi-class classification of transient events among six capacitor switching conditions, namely base case, pre-insertion resistor, pre-insertion inductor, current limiting reactor, 6% reactor, and synchronous closing. The methodology is validated using PSCAD/EMTDC simulations under isolated and back-to-back capacitor switching scenarios. The results demonstrate that the proposed DWT–AI approach achieves high classification accuracy exceeding 95%, outperforming conventional methods based on DWT alone and DWT combined with FIS. Furthermore, the proposed method improves protection system performance by reducing false tripping caused by transient inrush currents, while maintaining reliable fault detection capability. The findings confirm that integrating time–frequency signal processing with AI-based classification provides an effective and practical solution for transient event discrimination in MSC capacitor bank systems. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, An Approach for Voltage Drop Improvement in Distribution Line Using High-Voltage Capacitor Bank(2025-01-01); - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Application of probabilistic neural networks using high-frequency components’ differential current for transformer protection schemes to discriminate between external faults and internal winding faults in power transformers(2021-11-01); ; Leelajindakrairerk, MonthonInternal and external faults in a power transformer are discriminated in this paper using an algorithm based on a combination of a discrete wavelet transform (DWT) and a probabilistic neural network (PNN). DWT decomposes high-frequency fault components using the maximum coefficients of a 1/4 cycle DWT as input patterns for the training process in a decision algorithm. A division algorithm between a zero sequence of post-fault differential current waveforms and the differential current coefficient in the 1/4 cycle DWT is used to detect the maximum ratio and faults. The simulation system uses various study cases based on Thailand’s electricity transmission and distribution systems. The simulation results demonstrated that the PNN and BPNN are effectively implemented and perform fault detection with satisfactory accuracy. However, the PNN method is most suitable for detecting internal and external faults, and the maximum coefficient algorithm is the most effective in detecting the fault. This study will be useful in differential protection for power transformers. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, An approach for voltage drop improvement in 22 kV PEA distribution system based on high voltage capacitor placement(2023-10-01); - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Effect of Multi-wind Distributed Generators Location during Fault Occurrence in Distribution System(2023-01-01); ; In the recent decade, there has been a rising concern about energy consumption and environmental issues. This trend has shifted the focus of electric utility from fossil fuels to renewable energy. Thus, distributed generation (DG) that generated power from renewable energy sources has been on the rise. However, the presence of DG can affect the operation of power system protection and may cause a technical issue with the equipment. So, this paper investigates the impacts of wind power-based DG installed on the distribution system in Thailand using PSCAD software. The case study system is modeled after part of the Provincial Electricity Authority (PEA) distribution network in Northern Thailand. The comparative study with the case without DG has also been done on various parameters such as type of faults, location, and number of DG. The result from a study reveals the impact of DG on the distribution system characteristics, which changing drastically. Thus, an analysis of the impact of DG on the system must be done to address its effects and ensure the reliability of the power system. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Impact of Building Envelope Materials on Energy Usage and Performance of Evaporative Cooling System in Residential Building(2024-08-01); A large proportion of building energy consumption in tropical countries like Thailand primarily comes from air conditioning systems used to maintain the comfort level of building occupants. This paper aims to evaluate the performance of an alternative cooling system based on the evaporative principle in terms of thermal characteristics and energy consumption. A simulation model using computational fluid dynamics (CFD) software ANSYS version 16.0 and an actual experimental setup at the laboratory level were built to verify the results of the proposed cooling system. Additionally, factors that influence performance, such as components of the building envelope and the building’s orientation, are considered. This research aims to demonstrate the impact of building envelope material and building characteristics on the energy usage in air conditioning systems and to propose an energy-efficient cooling system. The results demonstrate that the proposed cooling system can reduce the temperature inside the building. However, the characteristics of the building also affect the energy performance. Thus, the proposed cooling system, in combination with an efficient envelope material, can achieve energy savings of around 35–43%. Therefore, a combination of the proposed cooling system and optimal building design can ensure comfort for building occupants while saving energy. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Investigation and Study of High Voltage Capacitor Bank Techniques for Voltage Drop Improvement in 22-kV Distribution Line(2025-01-01); Voltage drop in distribution lines contributes to power losses, leading to a decrease in the overall efficiency of the electrical power system. In this paper, we investigate methods to improve voltage drop through capacitor bank allocation techniques, specifically installation at the end of the distribution line, the 1/2-kvar rule, and the 2/3-kvar rule. In the case study, a 22 kV overhead distribution line in Thailand is utilized as a model to analyze voltage drop improvement. The study is conducted using PSCAD software to simulate and evaluate the effectiveness of various capacitor bank allocation techniques in enhancing voltage drop in the distribution line. In addition, the impact of capacitor bank placement and sizing on voltage drop mitigation in a distribution line is analyzed through a proposed mathematical framework. This analysis considers the interaction between reactive current compensation and impedance of a distribution line, ensuring an optimized approach for capacitor bank deployment to enhance voltage drop. The results emphasize that the capacitor bank installation at the end of the distribution line yields the most substantial voltage drop improvement. This is attributed to the utilization of larger capacitor bank capacities compared to the 1/2-kvar and 2/3-kvar methods. Furthermore, the mathematical analysis confirms that both the placement and sizing of capacitor banks play a crucial role in voltage drop mitigation. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Study on coordination of protective relays in distribution system with distributed generation(2020-01-01); ; ; In the recent decade, many countries around the globe have been increased the proportion of electrical power generation from renewable energy sources, which results in rising in the penetration level of distributed generation (DG). However, the installation of DG into the distribution system may raise many issues that can impact the distribution system in both the technical and economic aspects. When DG is connected to a distribution system, it can affect the performance of the system and the protective device already installed owing to the change of voltage level, short-circuit level and direction of power flow in the system. For this reason, a protective device may cause the malfunction because the bus impedance of the system is changed; this will result in a change of the current in each bus. This paper aims to study the coordination between the protective relay and the DG installed into the distribution system. The distribution system under investigation is a part of the Provincial Electricity Authority (PEA). Under this research, DG data that are connected to the PEA distribution is used. The simulations are performed using digital simulation and electrical network calculation program (DIgSILENT).