Poolsak Koseeyaporn

Intelligent Model-Based Control of a Standalone Photovoltaic/Fuel Cell Power Plant With Supercapacitor Energy Storage

A renewable energy hybrid power plant, fed by photovoltaic (PV) and fuel cell (FC) sources with a supercapacitor (SC) storage device and suitable for distributed generation applications, is proposed herein. The PV is used as the primary source; the FC acts as a backup, feeding only the insufficiency power (steady-state) from the PV; and the SC functions as an auxiliary source and a short-term storage system for supplying the deficiency power (transient and steady-state) from the PV and the FC. For high-power applications and optimization in power converters, four-phase parallel converters are implemented for the FC converter, the PV converter, and the SC converter, respectively. A mathematical model (reduced-order model) of the FC, PV, and SC converters is described for the control of the power plant. Using the intelligent fuzzy logic controller based on the flatness property for dc grid voltage regulation, we propose a simple solution to the fast response and stabilization problems in the power system. This is the key innovative contribution of this research paper. The prototype small-scale power plant implemented was composed of a PEMFC system (1.2 kW, 46 A), a PV array (0.8 kW), and an SC module (100 F, 32 V). Experimental results validate the excellent control algorithm during load cycles.

Fuzzy logic based DC bus voltage control of a stand alone photovoltaic/fuel cell/supercapacitor power plant

A renewable energy hybrid power plant, fed by photovoltaic (PV) and fuel cell (FC) sources with a supercapacitor (SC) storage device and suitable for distributed generation applications, is proposed herein. The PV is used as the primary source; the FC acts as a backup and a long-term storage system, feeding only the insufficiency power (steady-state) from the PV; and the SC functions as an auxiliary source and a short-term storage system for supplying the deficiency power (transient and steady-state) from the PV and the FC. A mathematical model (reduced-order model) of the FC, PV, and SC converters is described for the control of the power plant. Using the intelligent fuzzy logic controller based on the flatness property for dc grid voltage regulation, we propose a simple solution to the dynamic optimization and stabilization problems in the power system. This is the key innovative contribution of this research paper. The prototype small-scale power plant implemented was composed of a PEMFC system (1.2 kW, 46 A), a PV array (0.8 kW), and a SC module (100 F, 32 V). Experimental results validate the excellent control algorithm during load cycles.

An enhanced adaptive algorithm for PLI cancellation in ECG signals

This paper presents a technique for determining amplitude and phase of the power line interference (PLI), which is in sinusoidal waveform, by using two consecutive samples under identified sampling rate. The amplitude and phase information will then be employed to initialize parameters of the adaptive noise canceling algorithm whose the interfering noise is modeled as orthogonal sinusoidal functions. Based on computer simulation, the performance of the adaptive algorithm is improved over the conventional algorithm. In addition, the results in various cases of the PLI show that the proposed technique is superior to the results of the ASIC algorithm.

Fully current controllable AM/FM modulator and quadrature sinusoidal oscillator based on CCCIIs

In this article, a sinusoidal oscillator, AM and FM signal generator based on translinear current conveyors is introduced. The frequency and amplitude of the proposed circuit can be controlled by the bias currents. When an input current is applied as an information signal to the first and the second CCCII+s (Current Controlled Current Conveyors), the network functions as an FM signal generator. Contrarily, an AM signal is obtained by employing such information signals applied to the third CCCII+. In addition, this network simultaneously produces two signals that are 90/spl deg/ different in phase resulting in quadrature sinusoidal signals. This circuit consists of three CCCII+s and two grounded capacitors where, without any external resistors, this circuit is then suitable for IC architecture. The PSPICE simulation results are depicted. The given results agree well with the theoretical anticipation where the power consumption is approximately 2.4 mW.

Amplitude modulation based on time-varying forced function of second-order oscillator circuit

This paper presents a novel technique of amplitude modulation which is based on a second-order oscillator circuit. By using the multi-time technique to analyze a second-order system for time-varying forced function, it is found that the systems forced response not only at an initial time but also at any arbitrary time is presented in term of the natural responses magnitude. It implies that amplitude of the natural response can directly be controlled by the forced response. For a condition that the forced response and the time-varying forced function is approximately identical, the resulted complete response of the second-order system therefore is amplitude modulation where the natural response and the time-varying forced function respectively represents sinusoidal carrier and information signals. To confirm the proposed technique, experimental results have been demonstrated which agree well with the given theoretical analysis

Fuzzy control law based-on flatness property for a DC link stabilization for a fuel cell/supercapacitor hybrid power plant

This paper presents a fuzzy control law based on differential flatness approach for distributed dc generation (nonlinear system) supplied by a fuel cell (FC) (main source) and supercapacitor (auxiliary source). The main technical feeble point of FCs is slow dynamics because the power slope is limited to prevent fuel starvation problems, improve performance and increase lifetime. The very fast power response and high specific power of a supercapacitor complements the slower power output of the main source to produce the compatibility and performance characteristics needed in a load. The energy in the system is balanced by dc bus energy regulation (or indirect voltage regulation). A supercapacitor module functions by supplying energy to regulate the dc bus energy. The FC, as a slow dynamic source in this system, supplies energy to the supercapacitor module in order to keep it charged. Using the intelligent fuzzy control law based on the flatness property, we propose straightforward solutions to hybrid energy management, dynamic and stabilization problems. To validate the proposed method, a hardware system is realized with analog circuits, and digital estimation is accomplished with a dSPACE controller. Experimental results with small-scale power plant (a polymer electrolyte membrane FC of 1200 W, 46 A and a supercapacitor module of 100 F, 500 A, and 32 V) in a laboratory corroborate the excellent control scheme during a load cycle.

Two low-voltage high-speed CMOS frequency-insensitive PWM signal generators based on relaxation oscillator

In this paper, two new simple PWM (Pulse Width Modulation) signal generators based on a modified CMOS relaxation oscillator are introduced. Translinear current dividers are proposed to improve the circuit performance such that it is frequency insensitive to the magnitude of an input signal. In addition, the precise PWM signal can be easily achieved under low voltage consumption and the output frequency can be ranged up to several megahertz. Furthermore, both voltage and current modulating signals can be applied. Based on the features and the simplicity of the circuits, it is very suitable for developing into Integrated Circuit (IC) form in communication applications. The simulation results through PSPICE show a good agreement with theoretical anticipation.

An Empirical Study of Policy Implementation of Thailand Talent Mobility Programme

This paper empirically examines the national policy deployment of talent mobility programme aiming to leverage innovation atmosphere in private sector as a part of national strategy to escape middle income country status. The main policy mechanism is to facilitate universities and research institutes to develop their internal regulations in accordance with the Cabinet approval such that their talents can be legally mobilised to conduct research or project in private companies for competitiveness improvement. Moreover, clearing houses or service centres were established to eliminate the gap between industry and university, whereas training programmes were also developed for capacity building purpose, especially for staffs in those centres. Lastly, facilitation resources such as management, research fund, and compensation were mutually supported by government agencies including National Science Technology and Innovation Policy Office and Office of the Higher Education Commission. Based on data collection from the talent mobility projects executed during 2014 to 2016, key success factors and barriers were observed and subsequently the policy recommendations were proposed for improving the programme implementation in future. Keywords: Talent Mobility, STI Policy, GEDP

AC power load controlling by using PWM based on phase locked loop

This paper proposes power load controlling by using PWM signal to on-off an electronic switch. With this technique, load current can be easily adjusted. For PWM signal, it is derived by using PLL. With the property of PLL, PWM signal whose frequency is synchronized with that of load power is generated. Consequently, phase of signal which is fed to load can be controlled all range of 360 degrees or 180 degrees. In addition, the experiment results show that linear relation between phase of signal and DC voltage.