Thepmanee, Teerawat
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Item type:Publication, Hybrid Posi cast - based PID - PDA Control Using System Identification for Continuous Tunnel Kilns(2026-06-30); ; This paper proposes a hybrid Posicast-based proportional-integral-derivative with proportional-derivative-acceleration (PID-PDA) controller for temperature regulation in delay-dominant continuous tunnel kilns. The controller is developed based on a system-identified second-order-plus-dead-time (SOPDT) model derived from industrial data and implemented in discrete time for programmable logic controllers (PLCs). A unified framework enables comparison with a standard PLC-based proportional-integral (PI) controller, an internal model control (IMC)-tuned PI controller, and a Smith Predictor-PI controller under identical conditions. Simulation results demonstrate faster response, negligible overshoot, and reduced tracking error, with improved settling time and lower, integral of absolute error (IAE), integral of squared error (ISE), and integral of time-weighted absolute error (ITAE), while maintaining comparable control effort. Robustness analysis confirms stable performance under plant perturbations, with IAE variations within approximately ± 10 (servo) and ± 1 (disturbance). The controller is validated on an Allen-Bradley PLC in a silicon controlled rectifier (SCR)-based heating system. Experimental results show improved steady-state performance, including reduced bias, lower mean absolute error (MAE) and root mean squared error (RMSE), reduced oscillation amplitude, and compliance within the ± 1 temperature band. The proposed approach provides a practical, robust, and high-performance solution for upgrading existing PLC-based systems without hardware modifications. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Sil assessment for tail gas treating process using layer of protection analysis(2018-06-01) - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Using genetic algorithm to manage and schedule temperature sensor calibration(2011-01-01); Masuchun, RuedeeCurrently, generating a schedule to calibrate temperature sensors for both laboratory calibration and field calibration are very time-consuming and inefficient, especially when several temperature sensors await for being calibrated and the due dates are required to be specified in advance. General rule of thumb used is first-come-first-served but the due date is difficult to determine in advance. Moreover, overview of which standards will be required and, if required, at what temperatures each of them should be set to cannot be globally visualized. Another method is to calibrate those temperature sensors requiring same temperature together but the experience is strictly required to avoid overwhelming calculation time. This paper presents the application of scheduling technique using genetic algorithm to schedule temperature sensor calibration. The fitness function is to minimize the time required to calibrate all temperature sensors. Our method takes little time to generate good schedule while the due date of each temperature sensor can be at once stated and the global view of required standards can be anticipated for further preparation. Moreover, our method is easy to use and suitable for anyone without the experience in scheduling temperature sensors. © 2011 ISSN. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Using wired hart and wirelesshart together for PLC and SCADA system(2015-01-01); ; ; Subpayasomboon, SirametWireless Technology has promoted in the process automation because it does not require power and communication wiring for field instruments that enables reduced engineering cost. At the same time, end-users consider the developments of process automation by using wireless devices due to the growing of the new plants and replacing analog or wired HART plants. The paper presents a technique to modify wired HART device to be WirelessHART device and to configure it for communication with other WirelessHART devices. A PLC (Programmable Logic Controller) and SCADA system is used to provide centralized device information, historian, and HMI. Installation and configuration techniques of wired HART, THUM adapter or repeater, WirelessHART, HART gateway are described. In addition, engineering and SCADA software are assigned based on OPC to share WirelessHART data with gateway, PLC and SCADA system. The experimental results by using S7-300 Siemens PLC, WW InTouch, and HART devices in level process control are included to confirm the system workability. Moreover, the technique could be applied to collect data for end-user support to quickly and easily gain the benefits of device diagnostic and to decide the plant operation and planning. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Safety and availability of basic process control using foundation fieldbus with control in the field - An experimental analysis(2017-08-01); Detailed knowledge of how to balance between safety and availability for instruments is essential to successful design and implementation in fieldbus-based process control systems. The configuration correctness is crucial to actually obtain the benefits of digital fieldbus technology used. In actuality, a number of device parameters must be set to provide the required functionalities. This paper focuses on improving safety and availability for the proportional-integral-derivative (PID) and cascade control strategies using Foundation Fieldbus (FF) with control in the field. The aim of this paper is to analyze the logical behaviors of PID and cascade loops in two conflicting purposes for studying how different configuration options affect the interlocks between function blocks located in instruments as well as the initialization and fail-safe mechanisms in response to invalid measurements. For safety purpose, the interested control loops are configured to bring the process to a safe state in the presence of a fault. For availability purpose, the interested control loops are configured to keep the process running in the event of a failure. A water tank process is utilized as a case study for control loop implementations. Interactions between the status propagation and mode shedding for demonstrating the studied control loop behaviors are examined experimentally in Petri net models. In addition, the function block options for bumpless transfer and setpoint tracking are also described. The proved configuration method for proper operations in balancing the interests of safety and availability is proposed. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, SIL assessment and implementation case study: A safety instrumented function for overpressure protection in a two-phase gas-liquid separator(2014-02-04); Khamkoon, PornpatcharaThis paper addresses the design of safety instrumented system by using risk graph method to evaluate risk assessment and safety integrity level (SIL), following IEC 61508/61511 standard. A sample control system of a gas-liquid separator has been studied. To conform the required safety integrity level (SIL), investigation of the probability failure on demand, PFD<inf>AVG</inf> has been calculated by simplified equation and design of safety instrumented system was then done. In this study, safety instrument function architecture, test interval and testing made a significant impact on the result of PFD<inf>AVG</inf> calculation. © 2014 ICIC International. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Reliability enhancement of LNG fuel gas supply system in combined-cycle power plant(2020-12-01); - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Safety enhancement for basic process control using 4-20 milliampere signal transmission(2021-08-01); - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Family of Fibonacci-Type Marx Generators with a Single Inductor in a Three-Phase Configuration(2024-01-01); High-voltage discharge applications have seen a widespread adoption of solid-state Marx generators (SSMGs) in recent years. In this paper, we propose a new hybrid solid-state Marx generator (HSSMG) with a single inductor. Through the application of a three-phase Fibonacci scheme, the HSSMG is capable of achieving a substantial increase in voltage output. Furthermore, the proposed HSSMG is able to generate high voltage efficiently with fewer components. The integration of the Fibonacci and boost modules is a crucial idea in the proposed technique, where the boost module increases the output voltage of the Fibonacci module to achieve higher output voltage. Regarding the proposed two-stage HSSMG, the theoretical feasibility of the proposed topology is confirmed by theoretical analysis and Simulation Program with Integrated Circuit Emphasis (SPICE) simulations. As a result of comparative analysis, it was found that the number of circuit components of the proposed two-stage HSSMG is approximately half that of the traditional SSMG. Moreover, the newly suggested two-stage HSSMG accomplishes more than 86% power efficiency at 5 W. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Reliability modeling of emergency shutdown function for heat recovery steam generator control(2016-10-01); This paper presents a method for evaluating reliability and unreliability of emergency shutdown function for a control system of heat recovery steam generator (HRSG), which is operated with active redundant for providing safety and protection. The studied triple-pressure HRSG for driving the steam turbine in a power plant consists of three sections: high pressure section, intermediate pressure section, and low pressure section. A safety shutdown is based on level and pressure sensing system with three pressure transmitters and three level transmitters in each section for implementing a voting algorithm in order to tolerate the failure ofone sensor. Fault tree analysis (FTA) is employed as a tool for analyzing probability functions ofsuccess and failure for three possible voting algorithm configurations. Based on the obtained modeling, complex data of the studied system are transformed to accurate prediction of its reliability and unreliability.