scholarly journals Small-signal analysis of a single-stage bridgeless boost half-bridge AC/DC converter with bidirectional switch

Author(s):  
Mohamad Affan Bin Mohd Noh ◽  
Mohd Rodhi Bin Sahid ◽  
Thang Ka Fei ◽  
Ravi Lakshmanan

A small-signal analysis of a single-stage bridgeless boost half-bridge alternating current/direct current (AC/DC) Converter with bidirectional switches is performed using circuit averaging method. The comprehensive approach to develop the small signal model from the steady state analysis is discussed. The small-signal model is then simulated with MATLAB Simulink. The small-signal model is verified through the comparison of the bode-plot obtained from MATLAB Simulink and the simulated large signal model in piecewise linear electrical circuit simulation (PLECS). The mathematical model obtain from the small-signal analysis is then used to determine the proportional gain K_p and integral gain K_i. In addition, the switch large-signal model is developed by considering the current and voltage waveforms during load transients and steady-state conditions.

Energies ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4806
Author(s):  
Jia Yao ◽  
Kewei Li ◽  
Kaisheng Zheng ◽  
Alexander Abramovitz

Switched inductor (SI) converters are popular in applications requiring a steeper conversion ratio. However, these converters operate a twin inductor switching cell, which complicates the small-signal modeling. This paper proposes an expeditious small-signal analysis method to model the SI converters. The offered modeling approach is hinged on the analogy existing between the SI converters and certain Tapped Inductor (TI) converters. It is suggested here that by virtue of the analogy of the SI converters and TI converters the small-signal model of the SI converter is identical to that of its ideal TI counterpart. Hence, the recently developed Tapped Inductor Switcher (TIS) methodology can be applied to the modeling of the SI converters as well. As an example, the small-signal model of the Switched Inductor Buck converter is obtained. Theoretical analysis was confirmed by simulation and experimental results. In addition, several other SI converters and their TI counterparts are identified.


Author(s):  
Mohamad Affan Bin Mohd Noh ◽  
Mohd Rodhi Bin Sahid ◽  
Vinesh Thiruchelvam

This paper proposes an isolated full bridgeless single stage alternating current-direct current (AC-DC) converter. The proposed converter integrates the operation of a pure bridgeless power factor correction with input boost inductor cascaded with center-tap transformer and half bridge circuit. In addition, the bidirectional switch can be driven with single control signal which further simplifies the controller circuit. It is also proved that this converter reduces the total number of components compared to some conventional circuit and semi-bridgeless circuit topologies. The circuit operation of the proposed circuit is then confirmed with the small signal model, large signal model, circuit simulation and then verified experimentally. It is designed and tested at 115 Vac, 50 Hz of input supply, and 20 Vdc output voltage with maximum output power of 100 W. In addition, the crossover distortion at the input current is minimize at high input line frequency.


Energies ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3921
Author(s):  
Cha ◽  
Kim ◽  
Park ◽  
Choi

This paper proposes the modeling and design of a controller for an inductive power transfer (IPT) system with a semi-bridgeless active rectifier (S-BAR). This system consists of a double-sided Inductor-Capacitor-Capacitor (LCC) compensation network and an S-BAR, and maintains a constant output voltage under load variation through the operation of the rectifier switches. Accurate modeling is essential to design a controller with good performance. However, most of the researches on S-BAR have focused on the control scheme for the rectifier switches and steady-state analysis. Therefore, modeling based on the extended describing function is proposed for an accurate dynamic analysis of an IPT system with an S-BAR. Detailed mathematical analyses of the large-signal model, steady-state operating solution, and small-signal model are provided. Nonlinear large-signal equivalent circuit and linearized small-signal equivalent circuit are presented for intuitive understanding. In addition, worst case condition is selected under various load conditions and a controller design process is provided. To demonstrate the effectiveness of the proposed modeling, experimental results using a 100 W prototype are presented.


Materials ◽  
2019 ◽  
Vol 12 (21) ◽  
pp. 3588
Author(s):  
Haojia Chen ◽  
Qiong Gao ◽  
Baoliang Qian ◽  
Lishan Zhao

Fundamentally different responses of a LiTaO 3 thin film detector are observed when it is subjected to short microwave pulses as the pulse intensity is altered over a wide range. We start from weak microwave pulses which lead to only trivial pyroelectric peak response. However, when the microwave pulses become intense, the normally expected pyroelectric signal seems to be suppressed and the sign of the voltage signal can even be completely changed. Analysis indicates that while the traditional pyroelectric model, which is a linear model and works fine for our data in the small regime, it does not work anymore in the large signal regime. Since the small-signal model is the key foundation of electromagnetic-wave sensors based on pyroelectric effects, such as pyroelectric infrared detecters, the observation in this work suggests that one should be cautious when using these devices in intense fields. In addition, the evolution of detector signal with respect to excitation strength suggests that the main polarisation process is changed in the large signal regime. This is of fundamental importance to the understanding on how crystalline solids interact with intense microwaves. Possible causes of the nonlinear behaviour is discussed.


2010 ◽  
Vol 57 (2) ◽  
pp. 427-437 ◽  
Author(s):  
A. Brambilla ◽  
G. Gruosso ◽  
M.A. Redaelli ◽  
G.S. Gajani ◽  
D.D. Caviglia

2014 ◽  
Vol 6 (3-4) ◽  
pp. 243-251 ◽  
Author(s):  
Tom K. Johansen ◽  
Matthias Rudolph ◽  
Thomas Jensen ◽  
Tomas Kraemer ◽  
Nils Weimann ◽  
...  

In this paper, the small- and large-signal modeling of InP heterojunction bipolar transistors (HBTs) in transferred substrate (TS) technology is investigated. The small-signal equivalent circuit parameters for TS-HBTs in two-terminal and three-terminal configurations are determined by employing a direct parameter extraction methodology dedicated to III–V based HBTs. It is shown that the modeling of measured S-parameters can be improved in the millimeter-wave frequency range by augmenting the small-signal model with a description of AC current crowding. The extracted elements of the small-signal model structure are employed as a starting point for the extraction of a large-signal model. The developed large-signal model for the TS-HBTs accurately predicts the DC over temperature and small-signal performance over bias as well as the large-signal performance at millimeter-wave frequencies.


Sign in / Sign up

Export Citation Format

Share Document