(Abstract)
terça-feira, 22 de novembro de 2022
Doctoral Dissertation A Three-Phase SCVD Based Boost Inverter with Low Common Mode Voltage for Transformerless Photovoltaic Grid-Connected System Department of Electrical Engineering Graduate School, Chonnam National University BY Tran Tan Tai
(Abstract)
This study deals with a new type of inverter called a three-phase SCVD based boost
inverter. The introduced structure is a combination of an SCVD network and the three-phase
bridge to restrict the common-mode voltage. Therefore, the introduced inverter can produce
a high output voltage from the low input voltage. The DC-bus voltage of the introduced
solution stands at twice of the input voltage. Moreover, the variation in common-mode
voltage can o be restricted within one-sixth of DC-bus voltage. Modeling, circuit analysis,
operating principles, and a comparison between the introduced SCVD based boost inverter
with the other VSIs are performed. To confirm the performance improvements of the
introduced SCVD based boost inverter, a preliminary prototype of the introduced SCVD
based boost inverter is built in the laboratory and the simulation studies based on PLECS
environment and experimental studies are performed. Besides that, a modified SCVD based
boost inverter is also introduced to step up the DC-bus voltage to triple of input voltage
instead of twice of input voltage like that in the proposed SCVD based boost inverter.
Furthermore, a common-mode voltage of the modified SCVD based boost inverter is
x
canceled through switching the four extra active-switches based on the Boolean logic
function. As a result, common-mode voltage is maintained as constant at the value of 0 V
during all time. Moreover, the voltage stress across additional semiconductor devices is
standing at one-third of DC-bus voltage. The simulation studies based on PLECS
environment prove the effectiveness of the modified SCVD based boost inverter. Finally, to
validate the performance, operating principle, and feasibility of the modified SCVD based
boost inverter, the experimental studies based on the laboratory prototype with a DSP
F280049C are carried out.
Doctoral Dissertation
A Three-Phase SCVD Based Boost Inverter with
Low Common Mode Voltage for Transformerless
Photovoltaic Grid-Connected System
Department of Electrical Engineering
Graduate School, Chonnam National University
BY Tran Tan Tai
(Abstract)
This study deals with a new type of inverter called a three-phase SCVD based boost
inverter. The introduced structure is a combination of an SCVD network and the three-phase
bridge to restrict the common-mode voltage. Therefore, the introduced inverter can produce
a high output voltage from the low input voltage. The DC-bus voltage of the introduced
solution stands at twice of the input voltage. Moreover, the variation in common-mode
voltage can o be restricted within one-sixth of DC-bus voltage. Modeling, circuit analysis,
operating principles, and a comparison between the introduced SCVD based boost inverter
with the other VSIs are performed. To confirm the performance improvements of the
introduced SCVD based boost inverter, a preliminary prototype of the introduced SCVD
based boost inverter is built in the laboratory and the simulation studies based on PLECS
environment and experimental studies are performed. Besides that, a modified SCVD based
boost inverter is also introduced to step up the DC-bus voltage to triple of input voltage
instead of twice of input voltage like that in the proposed SCVD based boost inverter.
Furthermore, a common-mode voltage of the modified SCVD based boost inverter is
canceled through switching the four extra active-switches based on the Boolean logic
function. As a result, common-mode voltage is maintained as constant at the value of 0 V
during all time. Moreover, the voltage stress across additional semiconductor devices is
standing at one-third of DC-bus voltage. The simulation studies based on PLECS
environment prove the effectiveness of the modified SCVD based boost inverter. Finally, to
validate the performance, operating principle, and feasibility of the modified SCVD based
boost inverter, the experimental studies based on the laboratory prototype with a DSP
F280049C are carried out.
VIEW FULL DOCTORAL DISSERTATION:
LINK ALTERNATIVO DOCTORAL DISSERTATION:
sexta-feira, 18 de novembro de 2022
GaN MOSFET를 이용한 유도전동기 구동용 고효율 인버터에 관한 연구 = A Study on the high efficiency inverter for driving an induction motor using GaN MOSFET by Park, Sang-Yong- Dept. of Electronic Engineering The Graduate School Hanyang University
A Study on the High Efficiency Inverter for Driving an
Induction Motor using GaN MOSFET
Park, Sang-yong
Dept. of Electronic Engineering
The Graduate School
Hanyang University
ABSTRACT
It was proved in this paper that the efficiency of the inverter using GaN
MOSFET ,which is regarded as a next generation power semiconductor,
was much improved comparing the efficiency to the counterpart using the
conventional Si MOSFET. Comparing the characteristics of GaN MOSFET
to those of Si MOSFET, GaN MOSFET shows very low on resistance and
very fast switching speed due to the high breakdown voltage and very
small parasitic capacitances. Therefore, using GaN MOSFET as switching
devices of the inverter, it is expected that the efficiency and characteristics
of the inverter can be improved since the switching and conduction losses
and switching noise can be reduced.
In this paper, to demonstrate the superiority of GaN MOSFET to Si
MOSFET, the inverter using GaN MOSFET for driving a 2.2 kW induction
motor was fabricated. The design specification of the inverter fabricated is
as follows: input voltage is 220 Vac, switching frequency is 20 kHz, and
the operating frequency is 0 to 70 Hz. The fabricated inverter was tested
and the normal operation of the inverter was confirmed. Finally the
efficiency of the inverter was measured and the results of measured
efficiency was compared to those of Si MOSFET inverter with the same
specification as the GaN MOSFET inverter fabricated. From the
comparison results, it is known that the efficiency of the GaN MOSFET
inverter is superior to that of Si MOSFET inverter at the full range of
load. The maximum efficiency of the GaN MOSFET inverter was
measured as 98.41 %.
VIEW FULL TEXT:
Assinar:
Postagens (Atom)