Suwat Sikkabut

Control of High-Energy High-Power Densities Storage Devices by Li-ion Battery and Supercapacitor for Fuel Cell/Photovoltaic Hybrid Power Plant for Autonomous System Applications

This study presents an energy management approach for a hybrid energy system comprised of a photovoltaic (PV) array and a polymer electrolyte membrane fuel cell (PEMFC). Two storage devices [a Li-ion battery module and a supercapacitor (SC) bank] are used in the proposed structure as a high-energy high-power density storage device. Multisegment converters for the PV, fuel cell (FC), battery, and SC are proposed for grid-independent applications. Nonlinear differential flatness-based fuzzy logic control for dc-bus voltage stabilization for power plant is investigated. To validate the control approach, a hardware system is realized with analog circuits for the PV, FC, battery, and SC current control loops (inner controller loops), and with numerical calculation (dSPACE) for the external energy control loop. Experimental results with small-scale devices [a PV array (800 W, 31 A), a PEMFC (1200 W, 46 A), a Li-ion battery module (11.6 Ah, 24 V), and an SC bank (100 F, 32 V)] demonstrate the excellent energy-management scheme 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.

DC bus stabilization of Li-Ion battery based energy storage for hydrogen/solar power plant for autonomous network applications

This paper presents an energy management approach for a hybrid energy system comprised of a photovoltaic (PV) array and a polymer electrolyte membrane fuel cell (PEMFC). A single storage device, i.e., a Li-ion battery module, is used in the proposed structure. Linear proportional-integral (PI) and nonlinear flatness-based controllers for dc bus stabilization for power plants are compared. To verify the control approaches, a hardware system is realized with analog circuits for the PV, FC, and battery current control loops (inner controller loops) and with numerical calculation (dSPACE) for the external energy control loops. Experimental results with small-scale devices [namely, a PV array (800 W, 31 A), a PEMFC (1200 W, 46 A), and a Li-ion battery module (11.6 Ah, 24 V)] illustrate the excellent energy management scheme during load cycles, and the nonlinear differential flatness-based control was determined to provide improved dc bus regulation relative to a classical linear PI control method.

Control strategy of solar/wind energy power plant with supercapacitor energy storage for smart DC microgrid

This paper presents an original control algorithm for a hybrid energy system with a renewable energy source: a photovoltaic (PV) array and a wind turbine (WD). A single storage device, a supercapacitor (SC) module, is in the proposed structure. The very fast power response and high specific power of a SC complements the insufficient power output of the main sources to produce the compatibility and performance characteristics needed in a load. To verify the proposed principle, a hardware system is realized with analog circuits and with numerical calculation (dSPACE) for the energy control loops. Experimental results with small-scale devices, namely, a wind turbine generator (500 W), a photovoltaic array (800 W, 31 A) manufactured by the Ekarat Solar Company and a SC module (100 F, 32 V), illustrate the excellent energy-management scheme during load cycles.

Comparative study of control approaches of Li-Ion battery/supercapacitor storage devices for fuel cell power plant

This study presents energy management approaches for a fuel cell (FC) power plant for autonomous system applications. Two storage devices (supercapacitor (SC) and Li-ion battery) are used in the proposed structure. Linear proportional-integral (PI) and nonlinear flatness-based controllers for dc bus stabilization for power plants are compared. Experimental results with small-scale devices [namely, a PEMFC (1200 W, 46 A), a Li-ion battery module (11.6 Ah, 24 V), and a supercapacitor bank (100 F, 25 V)] illustrate the excellent energy-management scheme during motor drive cycles.

Control algorithm of renewable energy power plant supplied by fuel cell/solar cell/ supercapacitor power source

A renewable energy hybrid power plant, fed by photovoltaic (PV) and fuel cell (FC) sources with a supercapacitor storage device and suitable for distributed generation applications, is proposed herein. The PV is used as the main generator; the FC acts as a power source, feeding only the insufficiency power (steady-state) from the PV; and the supercapacitor functions as an auxiliary source for supplying the deficiency power (transient and steady-state) from the PV and the FC. Using the nonlinear approach based on the flatness property, we propose a simple solution to the dynamics, optimization, stabilization, and robustness problems in the hybrid power system. This is the key innovative contribution of this research paper. The prototype small-scale power plant studied was composed of a PEMFC system (1.2 kW), a PV array (0.8 kW), and a supercapacitor module (100 F). Experimental results in laboratory authenticate the excellent control algorithm during load cycles.

Differential flatness control approach for fuel cell/solar cell power plant with Li-ion battery storage device for grid-independent applications

A solar cell/hydrogen energy power plant, fed by photovoltaic (PV) and fuel cell (FC) sources with a Li-ion battery (Bat) storage device and suitable for distributed generation applications, is proposed herein. The PV is used as the main source; the FC acts as a backup, feeding only the insufficiency power (steady-state) from the PV; and the battery 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 battery converter, respectively. Using the non-linear estimation based on the differential flatness property for dc bus energy regulation, we propose a simple solution to the fast response and stabilization problems in the power system. This is the main contribution of this research paper. The prototype small-scale power plant implemented was composed of a PEMFC system (1.2 kW, 46 A [NexaTM Ballard Power Systems]), a PV array (0.8 kW [Ekarat Solar Cell]), and a Li-ion module (11.6 Ah, 24 V [SAFT Technology]). Experimental results validate the excellent control algorithm during load cycles.

Current-fed full-bridge DC-DC converter with nonlinear control scheme

This paper presents a control algorithm for dealing with the constraints of energy power source and a current-fed full-bridge converter. The advantages of this control scheme include transient and steady-state responses and robustness. The prototype of 26 V/100 V 250 W and its controller were implemented. A dSPACE DS1104 was used to implement the outer control loop by using flatness systems properties. An analog control card was employed as an inner control loop by using hysteresis-based PWM. The validation of the proposed control was demonstrated through experiment results.

Differential flatness based control of supercapacitor substation for DC grid system

This paper presents a new control approach for dc-link stabilization in weak networks that use supercapacitors (SC) as the energy storage substation. A 4-phase parallel converter with interleaved switching technique is presented as a 2-quadrant SC converter, and a reduced-order mathematical model of the system is described for power plant control. Using a nonlinear control approach based on the flatness property, we propose a straightforward solution to dynamic and stabilization problems in the power electronics systems of networks, which is the key contribution described in this paper. To validate the proposed method, a hardware system is modeled using digital estimation with a DS1104 dSPACE controller platform. We analyze a prototype small-scale network that uses a 700 W six-pulse rectifier as a dc main generator and a 100 F, 32 V SC bank as an energy storage substation. Finally, the utility of the control algorithm is validated using experimental results measured during load cycles.

Differential flatness based-control of fuel cell/photovoltaic/wind turbine/supercapacitor hybrid power plant

A renewable energy hybrid power plant, fed by photovoltaic (PV), wind turbine (WT), and fuel cell (FC) sources with a supercapacitor (SC) storage device and suitable for distributed cogeneration applications, is proposed herein. The PV, the WT, and the FC are used as the main source; 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 main sources. Based on the flatness property for dc grid voltage stabilization, we propose a simple solution to the fast response and stabilization problems in the power system. This is the innovative contribution of this 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), a WT (1 kW), and an SC module (100 F, 32 V). Experimental results validate the excellent control algorithm during load cycles.