• Journal of Electrical Engineering and Technology
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• 제5권4호
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• pp.561-570
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• 2010

This paper presents an advanced dynamic simulation model of a proton exchange membrane fuel cell for the optimal design of a fuel cell power conditioning system (FC-PCS). For the development of fuel cell models, the dynamic characteristics of the fuel cell are considered, including its static characteristics. Then, software fuel cell simulation is realized using Matlab-Simulink. Specifically, the design consideration of PCS (i.e., power semiconductor switch, capacitor, and inductor) is discussed by comparatively analyzing the developed simulator and ideal DC source. In addition, a cosimulation between the fuel cell model and PCS realized using the PSIM software is performed with the help of the SimCoupler module. Detailed analysis and informative simulation results are provided for the optimal design of fuel cell PCS.

• Journal of Power Electronics
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• 제7권2호
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• pp.174-180
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• 2007

In this paper, a simple control method for two-stage utility grid-connected photovoltaic power conditioning systems (PCS) is proposed. This approach enables maximum power point (MPP) tracking control with post-stage inverter current information instead of calculating solar array power, which significantly simplifies the controller and the sensor. Furthermore, there is no feedback loop in the pre-stage converter to control the solar array voltage or current because the MPP tracker drives the converter switch duty cycle. This simple PCS control strategy can reduce the cost and size, and can be utilized with a low cost digital processor. For verification of the proposed control strategy, a 2.5kW two-stage photovoltaic grid-connected PCS hardware which consists of a boost converter cascaded with a single-phase inverter was built and tested.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
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• pp.1784-1787
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• 2005

This paper presents the development and testing of a power conditioning system(PCS) for application to a 100kW Molten Carbonate Fuel Cell(MCFC) generation system. The MCFC generation system is a part of a four year government funded research project that began in 2001. This paper presents the results of various tests and performance verification of the 100kW PCS using a DC power system that simulates the DC output of the MCFC fuel cell. Performance of the DC/DC, DC/AC converters were verified, and basic control functions such as grid connection, protection and characteristics of each components were tested. The tests were performed under light load and rated load conditions to verify the operation efficiency, power quality effects, and stability of the PCS.

• 전력전자학회논문지
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• 제23권2호
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• pp.101-105
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• 2018

Shortage of electric power occurs frequently along with increased electric power demand. ESS is a precaution to solve this issue. Household ESS has a capacity of approximately 3 kW/7 kWh. Household ESS batteries are typically designed with nominal voltages between 40 and 50 V. To connect household ESS with a 220 V AC system, low battery voltages in power conditioning system (PCS) should be boosted. To boost low battery voltage and match it with AC grid voltage, the use of a transformer for a commercial frequency can be considered. To attenuate switching harmonics of the household single-phase ESS-PCS, LC filter can be installed in two positions: on the primary side or on the secondary side of a transformer. A method has been used generally in single-phase inverters for the ESS-PCS. In another method, however, the output efficiency of the ESS-PCS may be decreased. Parasitic components of the transformer can affect voltage losses, when the square wave with the switching frequency in the ESS-PCS is passed through the transformer windings. In this work, the characteristics of the transformer according to the position of an LC filter are investigated for household single-phase ESS-PCS.

• Journal of Power Electronics
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• 제9권2호
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• pp.300-307
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• 2009

In this paper, design and control is proposed for a four input-series-output-series-connected ZVS full bridge converter for the photovoltaic power conditioning system (PCS). The novel topology for a photovoltaic (PV) DC/DC converter that can dramatically reduce the power rating and increase the efficiency of a PV system by analyzing PV module characteristics is proposed. The control scheme, including an input voltage controller is proposed to achieve equal sharing of the input voltage as well output voltages by a four series connected module. Design methods for ZVS power stage are also introduced. The total PV system is implemented for a 250-kW PV power conditioning system (PCS). This system has only three DC/DC converters with a 25-kW power rating and uses only one-third of the total PV PCS power. The 25-kW prototype PV DC/DC converter is introduced to verify experimentally the proposed topology. In addition, an experimental result shows that the proposed topology exhibits good performance.

• 한국태양에너지학회 논문집
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• 제35권6호
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• pp.9-15
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• 2015

In this paper, a parallel operating technique for the stand alone photovoltaic (PV) power conditioning system (PCS) is proposed. The proposed parallel operating technique can increase the power rating of the system easily. Also, it provide three-phase connection function. The proposed technique does not separated master and slave system. Also, it does not use the separated synchronization line. Therefore, the PCS can supply continuous power even if one of the PCS breaks down. This technique is composed of a phase locked loop (PLL) control, droop control, current limit control and etc. Experimental result obtained on 2-kW prototype to verify the proposed technique.

• 전력전자학회논문지
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• 제15권6호
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• pp.477-486
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• 2010

최근 PCS 시스템은 고집적화, 고효율화 그리고 고밀도화 되는 추세에 있다. 이러한 조건을 만족하기 위하여 두개의 공진탱크를 갖는 LLC 공진형 인버터와 LF(Low Frequency) Cyclo-converter로 구성된 PCS를 제안하였다. 본 논문에서는 제안된 회로의 동작모드와 이론에 대해 서술하였고 400W급 시제품을 제작하고, 계통전압(110Vac 60Hz)에 연결하여 실험 적용하였다.

• 전력전자학회논문지
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• 제12권5호
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• pp.355-363
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• 2007

본 논문에서는 무변압기형 3상 계통연계 PV PCS (photovoltaic power conditioning system)를 제안하였다. 태양전지의 국소 최대 전력점에서 발전하는 것을 방지하여 최대 전력점에서 발전을 하도록 개선한 P&O (perturb and observe) 방식의 MPPT (maximum power point tracking) 알고리즘을 제안하였다. 3상 전압형 인버터를 외부 직류 링크 전압제어기, 내부 전류제어기, 그리고 마이크로컨트롤러로 구현하기에 적합하도록 간단화한 공간벡터 변조법을 통해 제어하여 3상 계통연계 시 단위 역률을 실현하였다. 그리고 시스템의 안정성 향상과 역률 개선을 위해 직류 링크 전압을 더 빠르고 정확하게 제어하기 위한 알고리즘을 제안하였다. 모든 알고리즘과 제어기를 하나의 마이크로컨트롤러로 구현하고 제안된 알고리즘과 제어기의 우수성을 실험을 통해 검증하였다.

• 한국안전학회지
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• 제34권1호
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• pp.14-20
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• 2019

This paper presents a safety assessment based approach for the safe operation for PCS(Power Conditioning System) of photovoltaic and energy storage systems, applying FTA. The approach established top events as power outage and a failure likely to cause the largest damage among the potential risks of PCS. Then the Minimal Cut Set (MCS) and the importance of basic events were analyzed for implementing risk assessment. To cope with the objects, the components and their functions of PCS were categorized. To calculate the MCS frequency based on IEEE J Photovolt 2013, IEEE Std. 493-2007 and RAC (EPRD, NPRD), the failure rate and failure mode were produced regarding the basic events. In order to analyze the top event of failure and power outage, it was assumed that failures occurred in DC breaker, AC breaker, SMPS, DC filter, Inverter, CT, PT, DSP board, HMI, AC reactor, MC and EMI filter and Fault Tree was drawn. It is expected that the MCS and the importance of basic event resulting from this study will help find and remove the causes of failure and power outage in PCS for efficient safety management.

• Journal of Power Electronics
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• 제14권5호
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• pp.827-833
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• 2014

This study proposes a coupled inductor method for the parallel operation of a power conditioning system (PCS). When primary and secondary currents flow in the same direction in a coupled inductor, total flux and inductance are cancelled; when currents flow in opposite directions, each flux becomes an individual inductor. These characteristics are applied in the parallel operation of a PCS. To connect at a grid code, abnormal current, which is barred under the grid connection code, is blocked by using a coupled inductor. A design based on the capacity and current duration time of a PCS is verified through hardware implementation. Experiment results show the effectiveness of variance reduction.