12-01-2013, 02:20 PM
FLEXIBLE POWER ELECTRONIC TRANSFORMER
ABSTRACT
The topology of PET can be developed in such a way to achieve multiport electrical system that converts variable input waveform to the desired output waveform; This paper proposes a new modular flexible power electronic transformer (FPET). it is constructed based on modules and a common dc link, Each module consists of three main parts, including modulator, demodulator, and high frequency isolation transformer (HFIT),here proposed topology can be expanded by connecting modules in series or parallel to obtain higher voltage or current ratings, and to form star/delta connections for three phase applications. here each port is composed of a full bridge dc-link inverter (FBDCI), HFIT, and a cycloconverter. The proposed FPET is flexible enough to meet future needs of power electronic centralized systems. The main feature of the FPET is the independent operation of modules each of which contains one port. Each port can be considered as input or output, because bidirectional power flow is provided. The voltage regulation is performed by the FBDCI using PSM method. The cycloconverter chooses the PSM pulses in such a way to provide positive or negative voltage polarity at the output. The algorithm for regulation of dc-link voltage is proposed, some ports are considered as “balancing ports” that provide energy to balance dc-link voltage in FPET. Here, the decrease of the dc-link voltage increases the current of dc link switches
The modules are connected to a common dc link that facilitates energy transfer among modules as well as ports. Therefore, a multiport system is developed, which the ports can operate independently. This merit is important for applications, where input and output voltages are different in many parameters. A measurement results of a laboratory prototype are presented to verify the capabilities of FPET in providing different output waveforms and controlling load side reactive power FPET can satisfy almost any kind of application, which are desired in power electronic conversion systems and meet future needs of electricity networks. The simulation results of high-voltage application are given to clarify the advantages of the proposed FPET over the recently developed PETs. To show the flexibility of the proposed PET,
ABSTRACT
The topology of PET can be developed in such a way to achieve multiport electrical system that converts variable input waveform to the desired output waveform; This paper proposes a new modular flexible power electronic transformer (FPET). it is constructed based on modules and a common dc link, Each module consists of three main parts, including modulator, demodulator, and high frequency isolation transformer (HFIT),here proposed topology can be expanded by connecting modules in series or parallel to obtain higher voltage or current ratings, and to form star/delta connections for three phase applications. here each port is composed of a full bridge dc-link inverter (FBDCI), HFIT, and a cycloconverter. The proposed FPET is flexible enough to meet future needs of power electronic centralized systems. The main feature of the FPET is the independent operation of modules each of which contains one port. Each port can be considered as input or output, because bidirectional power flow is provided. The voltage regulation is performed by the FBDCI using PSM method. The cycloconverter chooses the PSM pulses in such a way to provide positive or negative voltage polarity at the output. The algorithm for regulation of dc-link voltage is proposed, some ports are considered as “balancing ports” that provide energy to balance dc-link voltage in FPET. Here, the decrease of the dc-link voltage increases the current of dc link switches
The modules are connected to a common dc link that facilitates energy transfer among modules as well as ports. Therefore, a multiport system is developed, which the ports can operate independently. This merit is important for applications, where input and output voltages are different in many parameters. A measurement results of a laboratory prototype are presented to verify the capabilities of FPET in providing different output waveforms and controlling load side reactive power FPET can satisfy almost any kind of application, which are desired in power electronic conversion systems and meet future needs of electricity networks. The simulation results of high-voltage application are given to clarify the advantages of the proposed FPET over the recently developed PETs. To show the flexibility of the proposed PET,