Chainarin Ekkaravarodome

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.

Implementation of a DC-Side Class-DE Low-

An analysis and design of a single-stage electronic ballast with a dc-side Class-DE low-dv/dt resonant rectifier is studied in this paper to improve a poor power-factor and low line harmonic. The power-factor correction is achieved by utilize an output characteristics of a Class-DE rectifier, which is inserted between the front-end bridge rectifier and the bulk-filter capacitor. The design procedure is based on the principle of the Class-DE rectifier, which also ensures more accurate results and the proposed scheme provided a more systematic and feasible analysis methodology. The active switches can be operated under the soft-switching condition. By employing an electromagnetic interference filter after bridge rectifier, the standard-recovery diode for bridge rectifier can be employed, the cost can be reduced, the conduction angle of the bridge-rectifier diode current was increased, and low line harmonic distortion and a power factor near unity were achieved. The dc-side Class-DE rectifier is driven by a high-frequency current source, which is obtained from the square-wave output voltage of the Class-D series-parallel resonant inverter through an LC-series circuit. A prototype of the ballast, operating at an 84-kHz fixed frequency and a 220-V rms, 50-Hz line voltage, was utilized to drive a T8-36 W fluorescent lamp. The validity of this approach was confirmed by simulation and experimental results.

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This paper presents the use of a novel, single-stage high-power-factor electronic ballast with a symmetrical class-DE low-dυ/dt resonant rectifier as a power-factor corrector for fluorescent lamps. The power-factor correction is achieved by using a bridge rectifier to utilize the function of a symmetrical class-DE resonant rectifier. By employing this topology, the peak and ripple values of the input current are reduced, allowing for a reduced filter inductor volume of the EMI filter. Since the conduction angle of the bridge rectifier diode current was increased, a low-line current harmonic and a power factor near unity can be obtained. A prototype ballast, operating at an 84-㎑ fixed frequency and a 220-Vrms, 50-㎐ line input voltage, was utilized to drive a T8-36W fluorescent lamp. Experimental results are presented which verify the theoretical analysis.

Rectifier as a PFC for Electronic Ballast Application

An analysis and design of a zero-current-switching (ZCS) Class-D current-source driven rectifier for the lighting applications is presented, which is one of the resonant rectifiers as a power-factor corrector to improve a poor power-factor and high line current harmonic of a single-stage converter. A high power-factor is achieved by the utilization of output characteristics of a Class-D ZCS rectifier, which is inserted between the front-end bridge rectifier and the bulk-filter capacitor. The conduction angle of the bridge rectifier diode current was increased and a low-line current harmonic and a power-factor near unity can be obtained. The design procedure is based on the principle of the Class-D ZCS rectifier, which also ensures more accurate results and the proposed scheme provides a high efficiency and a more systematic and feasible analysis methodology. The active switches can be operated under the soft-switching condition. The validity of this approach was confirmed by simulation and experimental results.

Single-Stage High-Power-Factor Electronic Ballast with a Symmetrical Class-DE Resonant Rectifier

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.

Class-D Zero-Current-Switching Rectifier as Power-Factor Corrector for Lighting Applications

An analysis of the junction capacitance in resonant rectifiers which has a significant impact on the operating point of resonance circuits is studied in this paper, where the junction capacitance of the rectifier diode is to decrease the resonant current and output voltage in the circuit when compared with that in an ideal rectifier diode. This can be represented by a simplified series resonant equivalent circuit and a voltage transfer function versus the normalized operating frequency at varied values of the resonant capacitor. A low voltage to high voltage push-pull DC/DC resonant converter was used as a design example. The design procedure is based on the principle of the half bridge class-DE resonant rectifier, which ensures more accurate results. The proposed scheme provides a more systematic and feasible solution than the conventional resonant push-pull DC/DC converter analysis methodology. To increase circuit efficiency, the main switches and the rectifier diodes can be operated under the zero-voltage and zero-current switching conditions, respectively. In order to achieve this objective, the parameters of the DC/DC converter need to be designed properly. The details of the analysis and design of this DC/DC converter’s components are described. A prototype was constructed with a 62–88 kHz variable switching frequency, a 12 VDC input voltage, a 380 VDC output voltage, and a rated output power of 150 W. The validity of this approach was confirmed by simulation and experimental results.

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

This paper presented a high efficiency Class-D resonant inverter high power factor for induction heating multi-coils hardening application. The main function of the Class-D resonant inverter is to provide high frequency AC from bridge rectifier and LC filter input voltage. The advantages of this technique, the power switched are operated under the zero voltage switching condition and the leakage inductance of transformer can be used the LLC resonant. A prototype Class-D operating at a 102 kHz fixed frequency, 730 W maximum input power. Experimental results, induction hardening had a near unity power factor, total harmonic distortion of the input current THDi 6.5 %, it can be heat up 2 work pieces a same size diameter 9.5-mm from room temperature to 400°C within about 1 minutes and 92 % efficiency at full power.

Analysis and Implementation of a Half Bridge Class-DE Rectifier for Front-End ZVS Push-Pull Resonant Converters

A proposed parallel power converter with interleaving algorithm is chosen to boost a low dc voltage of photovoltaic (PV) to a dc bus utility level and then follows by inverter. Converters are controlled by interleaved switching signals, which have the same switching frequency and the same phase shift. By virtue of paralleling the converters, the input current can be shared among the cells or phases, so that high reliability and efficiency in power electronic systems can be obtained. In this paper, a nonlinear-control algorithm based on the flatness property of the system is proposed. Flatness provides a convenient framework for meeting a number of performance specifications on the power converter. To validate the proposed method, a prototype PV power converter (1.2-kW two-phase boost converters in parallel) is realized in the laboratory. The proposed control law based on the flatness property is implemented by digital estimation in a dSPACE 1104 controller card. Experimental results in the laboratory corroborate the excellent control scheme.

A high efficiency of a Class-D resonant inverter high power factor for induction heating multi-coils hardening application

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. Multi-segment converters for the PV, 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 are 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 photovoltaic array (800 W, 31 A), a PEMFC (1200 W, 46 A), a Li-ion battery module (11.6 Ah, 24 V), and a SC bank (100 F, 32 V)] demonstrate the excellent energy-management scheme during load cycles.

Photovoltaic power control based on differential flatness approach of multiphase interleaved boost converter for grid connected applications

This paper proposes a modified 4-phase interleaved converter for the FC power source for mobile based station applications. The ripple and harmonic content of the FC current is one of the various phenomena influencing FC lifetime. The main objective of this research is to minimize inductor size, capacitor, current/voltage ripples, and harmonic content. The main contribution is to presents a control law for a distributed dc generation supplied by a FC generator. Classically, to control the voltage, the current, or the power in the converter, a linearized technique is often used to study the stability and to select the controller parameters of the nonlinear converter. In this paper, a nonlinear-control algorithm based on the flatness property of the system is proposed. Utilizing the flatness property, we propose simple solutions to the system performance and stabilization problems. Design controller parameters are autonomous of the operating point. To authenticate the proposed control laws, a test bench is realized in the laboratory. The control algorithm is digitally implemented by dSPACE controller DS1104. Experimental results with small-scale device (a proton exchange membrane FC (PEMFC) of 1.2 kW, 26 V) substantiate the excellent performance during load cycles.