IET Power Electronics
Volume 6, Issue 9, November 2013
Volumes & issues:
Volume 6, Issue 9
November 2013
Marx dc–dc converter for high-power application
- Author(s): Etienne Veilleux ; Boon-Teck Ooi ; Peter W. Lehn
- Source: IET Power Electronics, Volume 6, Issue 9, p. 1733 –1741
- DOI: 10.1049/iet-pel.2013.0025
- Type: Article
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This study presents a dc–dc converter based on the Marx generator principle of charging capacitors in parallel followed by reconnection in series for discharging and for creating higher voltage. The topology uses solid-state switches like IGBTs as well as diodes. The concept and the operation of converter are described as well as design steps. The validity of the design is confirmed using PSCAD/EMTDC software package. The topology is compared with the conventional boost where the Marx dc–dc converter is shown to be competitive and even advantageous for higher dc gain. A cascade configuration is also presented and a 5 kW prototype with two stages made of two capacitors per stage is presented for experimental validation of the concept.
Design of a zero-voltage-switching large-air-gap wireless charger with low electric stress for electric vehicles
- Author(s): Chen Duan ; Chenguang Jiang ; Allan Taylor ; Kevin (Hua) Bai
- Source: IET Power Electronics, Volume 6, Issue 9, p. 1742 –1750
- DOI: 10.1049/iet-pel.2012.0615
- Type: Article
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This study proposes a design and development of a wireless power transfer system to charge the battery in electric vehicles. A parallel–parallel topology is adopted to realise 10–15 cm-distance power transfer using the resonance theory. Finite-element method is used to extract the coil parameters. The advantages of the proposed design compared with the previous similar research are (i) low operational frequency (42 kHz) which avoids the electromagnetic interference to the on-board automotive electronics equipment and (ii) low electric stress to the semi-conductor switches through using zero-voltage-switching technique. A 2 kW prototype to charge 200 V battery was built to experimentally verify the theoretical analysis. The overall system efficiency is ∼ 86%.
Modified electromagnetic microgenerator design for improved performance of low-voltage energy-harvesting systems
- Author(s): Rohan Dayal and Leila Parsa
- Source: IET Power Electronics, Volume 6, Issue 9, p. 1751 –1758
- DOI: 10.1049/iet-pel.2011.0503
- Type: Article
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The recent work in literature has shown the potential of energy harvesting as means to power wireless sensors. An energy harvester typically consists of a transducer and low-power management circuits. However, current systems suffer from crude design methodology with no synergy between these two stages. In this work, the authors present two design modules of a modified electromagnetic microgenerator system, which aid in the performance of the associated power converter. Startup is a critical issue for such systems, since the transducer voltage is quite low (a few hundred millivolts AC). For the first design module, a thin piezoelectric strip is added to the electromagnetic microgenerator to provide the start-up power for the converter system. The second module unifies the design of the input filter for the converter with the microgenerator. The microgenerator parasitics are utilised to satisfy the input filter requirements of the converter. Such an approach reduces the overall inductive losses in the system compared with other set-ups reported in the literature. Both the microgenerator and the input filter are fabricated along with a suitable AC–DC boost converter using discrete components. Both simulation and experimental results are shown to demonstrate the start-up capability of such a system and efficacy of the input filter design.
Hybrid split capacitors and split inductors applied in positive output super-lift Luo-converters
- Author(s): Fang Lin Luo and Hong Ye
- Source: IET Power Electronics, Volume 6, Issue 9, p. 1759 –1768
- DOI: 10.1049/iet-pel.2012.0634
- Type: Article
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Voltage lift technique has been successfully employed in design of DC/DC converters, for example, three series Luo-converters. However, the output voltage increases in arithmetic progression. Super lift (SL) technique is the most significant contribution in power electronics, for example, four series SL converters. Their output voltage increases in geometric progression. This study introduces a novel approach – SL technique armed by split capacitors and split inductors that implements the output voltage increasing in higher geometric progression. It effectively enhances the voltage transfer gain in power series as well. From the authors experimental results, the power rates of these converters can be few kW.
Laddered multilevel DC/AC inverters used in Solar Panel Energy systems
- Author(s): Fang Lin Luo and Hong Ye
- Source: IET Power Electronics, Volume 6, Issue 9, p. 1769 –1777
- DOI: 10.1049/iet-pel.2012.0496
- Type: Article
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Multilevel DC/AC inverters have various structures. They have many advantages. Unfortunately, most existing inverters content too many components (independent/floating batteries/sources, diodes, capacitors and switches). The author introduces the ‘laddered multilevel DC/AC inverters’ in this study, that is new approach of the development in this area. These inverters use much less components. Their simple structure and clear operation are obviously different from the existing inverters. Its application in Solar Panel Energy systems is successful. The simulation and experimental results strongly support our design. The measured total harmonic distortion illustrates the good quality of output sine wave. The authors believe that these inverters will draw much attention, and be applied in other renewable energy systems.
Digital pulse-width modulation controller based on fully table look-up for system-on-a-chip applications
- Author(s): Steve Hung-Lung Tu and Morris M.-H. Chiu
- Source: IET Power Electronics, Volume 6, Issue 9, p. 1778 –1785
- DOI: 10.1049/iet-pel.2012.0659
- Type: Article
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Design and implementation of a fully table look-up digital pulse-width modulation (DPWM) controller for high-frequency DC–DC buck conversion is presented. The controller comprises a 1 bit analogue comparator, a digital error process unit and a fully table look-up multi-phase DPWM. The interface of analogue-to-digital conversion is performed with the analogue comparator. Moreover, the proposed programmable memory is based on the table look-up multi-phase approach for the functions of the proportional-integral-derivative (PID) compensation, which alleviates the penalty of using large chip-area multipliers. As a result, the approach is very suitable for system-on-a-chip (SOC) implementation. A prototype test chip is realised to validate the mechanism of the proposed architecture.
A novel circuit for removing the entire current harmonic distortion generated by ohmic phase-cutting devices
- Author(s): Hassan Fathabadi
- Source: IET Power Electronics, Volume 6, Issue 9, p. 1786 –1791
- DOI: 10.1049/iet-pel.2012.0742
- Type: Article
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In this study and for the first time, a novel harmonic remover circuit is presented that removes the entire current harmonic distortion generated by the phase-cutting devices, which have ohmic input impedance (ohmic phase-cutting devices) such as lighting dimmers. The presented circuit has been designed and an experimental prototype has been built in the laboratory. It has a very exact operation to remove the total harmonic distortion (THD). It really removes the entire harmonic and the THD% of the compensated device is equal to the THD% of the same device without any phase cutting, so if the THD% of the system without any phase cutting is zero then the THD% of the compensated device will also be zero. The real measurement and experimental results are presented to validate the theoretically results and make a comparison between the advantages of this work and other related works.
Complex state variable- and disturbance observer-based current controllers for AC drives: an experimental comparison
- Author(s): Mehmet Dal ; Remus Teodorescu ; Frede Blaabjerg
- Source: IET Power Electronics, Volume 6, Issue 9, p. 1792 –1802
- DOI: 10.1049/iet-pel.2012.0748
- Type: Article
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In vector-controlled AC drives, the design of current controller is usually based on a machine model defined in synchronous frame coordinate, where the drive performance may be degraded by both the variation of the machine parameters and the cross-coupling between the d- and q-axes components of the stator current. In order to improve the current control performance an alternative current control strategy was proposed previously aiming to avoid the undesired cross-coupling and non-linearities between the state variables. These effects are assumed as disturbances arisen in the closed-loop path, extracted by a disturbance observer and then injected into the current controller. In this study, a revised version of a disturbance observer-based controller and a well known complex variable model-based design with a single set of complex pole are compared in terms of design aspects and performance evaluation by simulation and by experiment for two different sampling rates. Several comparative results that verify the promising performance of the proposed control scheme are presented. The advantages of the proposed controller are an easy implementation and offering a unique solution for the variation of the parameter and the cross-coupling effect. Moreover, it provides a better performance, smooth and low noisy operation with respect to the complex variable controller.
Analysis and design of a multi-channel constant current light-emitting diode driver based on high-frequency AC bus
- Author(s): Quanming Luo ; Shubo Zhi ; Can Zou ; Bo Zhao ; Luowei Zhou
- Source: IET Power Electronics, Volume 6, Issue 9, p. 1803 –1811
- DOI: 10.1049/iet-pel.2012.0696
- Type: Article
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To obtain sufficient luminance and achieve higher reliability, light-emitting diodes (LEDs) are usually arranged in parallel strings in many high-power applications. Since current imbalance should be avoided among the parallel LED strings, a multi-channel constant current LED driver based on high-frequency AC bus is proposed in this study. The proposed driver is composed of one resonant inverter followed by passive resonant rectifiers according to the number of LED strings. The amplitude of the high-frequency AC bus voltage is regulated by the resonant inverter and each LED string is individually powered with constant current by its corresponding passive resonant rectifier. The proposed driver is characterised by low cost and high efficiency. Finally, a prototype is built to verify the performance of the proposed driver.
Two-stage micro-grid inverter with high-voltage gain for photovoltaic applications
- Author(s): Mahrous El-Sayed Ahmed ; Mohamed Orabi ; Omar Mohamed AbdelRahim
- Source: IET Power Electronics, Volume 6, Issue 9, p. 1812 –1821
- DOI: 10.1049/iet-pel.2012.0666
- Type: Article
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This study proposes a new two-stage high voltage gain boost grid-connected inverter for AC-module photovoltaic (PV) system. The proposed system consists of a high-voltage gain switched inductor boost inverter cascaded with a current shaping (CS) circuit followed by an H-bridge inverter as a folded circuit and its switches operate at line frequency. The switched inductor boost converter (SIBC) has one switch operates like a continuous conduction mode. The maximum power of the PV module is achieved through the SIBC circuit whereas the grid connection requirements are accomplished using the CS circuit with the H-bridge inverter. The switch of the CS circuit is controlled with a sine wave modulation control scheme. The main advantages of the new proposed system are high boosting gain, lower switching losses and reduces the ground leakage current as all H-bridge switches operate at the line frequency. A 120 W prototype has been built and experimentally tested. It has been found that experimental results have a good matching with the proposed analysis and simulation results.
Analysis and design of split-capacitor resistive-inductive passive damping for LCL filters in grid-connected inverters
- Author(s): Arun Karuppaswamy Balasubramanian and Vinod John
- Source: IET Power Electronics, Volume 6, Issue 9, p. 1822 –1832
- DOI: 10.1049/iet-pel.2012.0679
- Type: Article
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Grid-connected inverters require a third-order LCL filter to meet standards such as the IEEE Std. 519-1992 while being compact and cost-effective. LCL filter introduces resonance, which needs to be damped through active or passive methods. Passive damping schemes have less control complexity and are more reliable. This study explores the split-capacitor resistive-inductive (SC-RL) passive damping scheme. The SC-RL damped LCL filter is modelled using state space approach. Using this model, the power loss and damping are analysed. Based on the analysis, the SC-RL scheme is shown to have lower losses than other simpler passive damping methods. This makes the SC-RL scheme suitable for high power applications. A method for component selection that minimises the power loss in the damping resistors while keeping the system well damped is proposed. The design selection takes into account the influence of switching frequency, resonance frequency and the choice of inductance and capacitance values of the filter on the damping component selection. The use of normalised parameters makes it suitable for a wide range of design applications. Analytical results show the losses and quality factor to be in the range of 0.05–0.1% and 2.0–2.5, respectively, which are validated experimentally.
Lithium-ion battery state of charge estimation based on square-root unscented Kalman filter
- Author(s): Hossein Gholizade-Narm and Mohammad Charkhgard
- Source: IET Power Electronics, Volume 6, Issue 9, p. 1833 –1841
- DOI: 10.1049/iet-pel.2012.0706
- Type: Article
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This study represents a method for estimating the state of charge (SOC) of lithium-ion batteries using radial basis function (RBF) networks and square-root unscented Kalman filter (KF). The RBF network is trained offline by sampled data from the battery in the charging process. This type of neural network finds the non-linear relation which is required in the state-space equations. The state variables include the battery terminal voltage and the SOC, at the previous sample and the present sample, respectively. The proposed method is tested experimentally on a lithium-ion battery with 1.2 Ah capacity to estimate the actual SOC of the battery. The experimental results of the proposed method show some advantages, which include: (i) it is not very sensitive to determine, precisely, the measurement and process noise covariance matrices such as Kalman filter and (ii). It contains lower noise on the output, in comparison with Adaptive extended Kalman filter (EKF).
A novel heuristic optimisation algorithm for automated design of resonant compensators for shunt active filters
- Author(s): Wanchak Lenwari and Nnamdi Okaeme
- Source: IET Power Electronics, Volume 6, Issue 9, p. 1842 –1850
- DOI: 10.1049/iet-pel.2012.0755
- Type: Article
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This study presents the automated control design for shunt active filters using a novel heuristic optimisation algorithm. The hybrid bacterial foraging optimisation algorithm is specifically developed for the automated optimisation of the modified resonant compensator for the compensation of all main harmonics, 5th, 7th, 11th and 13th. The compensator is based on the sinusoidal internal model principle providing excellent improvement in control accuracy and performance for harmonic signals. The compensator is implemented in a single rotating reference frame fixed to the supply voltage vector. The automated design procedure and a novel optimisation algorithm are presented in detail. Experimental results demonstrate the effectiveness of the proposed control design and the accuracy of current tracking performance.
The X-connected inverter: a topology with higher fundamental and reduced low-order harmonic voltages
- Author(s): Dipten Maiti and Sujit K. Biswas
- Source: IET Power Electronics, Volume 6, Issue 9, p. 1851 –1861
- DOI: 10.1049/iet-pel.2012.0756
- Type: Article
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A new inverter topology is presented in the paper, which produces a reduced low-order harmonic voltage waveform because of a natural harmonic cancellation process. Two switches of each limb operate at low switching frequency, whereas the other two switches of the same limb operate at higher switching frequency in conjunction with two additional capacitors. The four switches in each limb are controlled in such a way that the sequence of switching along with the voltage of two additional capacitors cancels out the low-frequency harmonics, thereby creating a pulse-width modulation (PWM) voltage with reduced low-order harmonics at the output with respect to the dc midpoint. By selection of the PWM pattern, the magnitude of fundamental voltage produced at the output can be higher than what would be achieved using sinusoidal PWM from the same dc bus voltage, without bothering about its inherent lower-order harmonics as they would be anyway cancelled. It is thus possible to achieve maximum possible dc bus utilisation theoretically.
Design-oriented model and critical inductance method for long life isolated power converters
- Author(s): Hon Man Pang and Bryan Man Hay Pong
- Source: IET Power Electronics, Volume 6, Issue 9, p. 1862 –1871
- DOI: 10.1049/iet-pel.2010.0214
- Type: Article
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For moderate-to-high power converters, electrolytic capacitor is an indispensable component. Life of electrolytic capacitor is critical compared with its semi-conductor counterparts. This study proposes a new model to analyse the converter life and to design the circuit to lower the current ripple in the electrolytic capacitor in order to reach for longer converter life. Two-stage power converter (a power factor correction converter followed by a DC–DC converter) is the typical practice for AC–DC converter. Forward converter and Flyback converters are the common choices for the downstream converter for this power range. Comparison between two modes of operation, discontinuous conduction mode and continuous conduction mode (CCM), for the two converter topologies shows a typical CCM Forward converter to have almost 300 times longer life than a CCM Flyback converter. Another focus of the work is to analyse the effect of circuit parameters on the converter life. A critical inductance is established to guide the design for long life converters.
Shunt reactive VAR compensator for grid-connected induction generator in wind energy conversion systems
- Author(s): Santhi Rajendran ; Uma Govindarajan ; Annelyn Beulah Reuben ; Aarthi Srinivasan
- Source: IET Power Electronics, Volume 6, Issue 9, p. 1872 –1883
- DOI: 10.1049/iet-pel.2012.0524
- Type: Article
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This work presents the control design for compensating reactive power requirement of induction generator (IG) in wind generation systems using STATic COMpensator (STATCOM). A mathematical model of IG is developed in synchronously rotating d–q–0 axis. The STATCOM is realised using voltage source inverter for which the switching function model is derived and employed here. Instantaneous p–q theory and symmetrical components theory are considered for reference current generation. The current control uses an optimal proportional controller designed using linear quadratic regulator (LQR) approach. Comparative analysis is also made between hysteresis current control and LQR. Simulation and experimental results indicate that the suggested control techniques make the supply power factor close to unity.
Implementation of soft-switching bidirectional flyback converter without auxiliary switch
- Author(s): Majid Delshad ; Nasrin Asadi Madiseh ; Mohammad Reza Amini
- Source: IET Power Electronics, Volume 6, Issue 9, p. 1884 –1891
- DOI: 10.1049/iet-pel.2012.0472
- Type: Article
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A new bidirectional flyback converter is introduced in this study. To provide soft-switching condition, two identical auxiliary circuits are applied to both sides of the converter, without using any extra switches. These circuits do not impose high voltage or current stresses on the converter. To transfer the power in each direction, only one switch is gated through pulse-width modulation technique. So, the control circuit of this converter is very simple. Regardless of the power flow direction, the switch of the converter is turned on under zero-current condition and is almost turned off under zero-voltage condition. The experimental results of the proposed bidirectional converter are presented to verify the theoretical analysis.
Analysis and implementation of a three-phase power factor correction scheme using modular Cuk rectifier for balanced and unbalanced supply conditions
- Author(s): Mallapu Gopinath Umamaheswari ; Govindarajan Uma ; Sangeetha Viswanathan
- Source: IET Power Electronics, Volume 6, Issue 9, p. 1892 –1908
- DOI: 10.1049/iet-pel.2012.0243
- Type: Article
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In this study, the analysis and design of a three-phase AC–DC converter followed by DC–DC Cuk converter modules to achieve unity power factor is presented. Two methods of reference current generation techniques are employed. In the first scheme, reference current is generated using instantaneous symmetrical component theory under balanced supply conditions. In the second scheme, extended synchronous detection methods such as equal current criterion, equal power criterion and equal impedance criterion are used for reference current generation under unbalanced supply conditions. The control strategy uses three hysteresis current controllers for source current shaping and an outer voltage loop with proportional-integral controller for load voltage regulation. To validate the proposed method, a prototype controlled by dSPACE signal processor is set up. Simulation and experimental results indicate that the proposed system offers regulated output voltage for wide load variations and provides power factor close to unity.
Multi-input voltage-summation converter based on switched-capacitor
- Author(s): Ye Yuan-mao and Ka Wai Eric Cheng
- Source: IET Power Electronics, Volume 6, Issue 9, p. 1909 –1916
- DOI: 10.1049/iet-pel.2013.0015
- Type: Article
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This study is to propose a multi-input converter which is designed based on switched-capacitor instead of magnetic components. The number of its inputs can be any figure. The output voltage level of the converter is the summation of its multiple input levels which share with a common neutral. There is no need to have any level-shift or boost-strap for adjusting the inputs. The number of active switches and capacitors required both are equal to the number of input sources. Only a pair of complementary pulse signals is needed to control all of these switches. The converter is operated under high frequency. Non-resonant version does not require resonant inductors and therefore they are of small size and simple structure. Small resonant inductor is also added in the resonant version to realise soft-switching and improve the conversion efficiency. The circuit analysis, design method and experimental verification are shown.
Doubly fed induction generator-based off-grid wind energy conversion systems feeding dynamic loads
- Author(s): Bhim Singh and Shailendra Sharma
- Source: IET Power Electronics, Volume 6, Issue 9, p. 1917 –1926
- DOI: 10.1049/iet-pel.2013.0010
- Type: Article
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This study deals with the operation and control of a doubly fed induction generator (DFIG)-based off-grid wind energy conversion system (WECS). Two back-to-back connected voltage source converters with intermediate DC-link supported with a battery energy storage system are used as a voltage and frequency controller (VFC). A field oriented control algorithm is used for VFC to perform as a load leveller, a load balancer, an active filter along with a VFC. Simulation results are verified on a developed prototype of VFC for DFIG-based off-grid WECS. The performance of WECS is demonstrated feeding non-linear and dynamic loads.
Comprehensive steady-state analytical model of a three-phase diode rectifier connected to a constant DC voltage source
- Author(s): Antonino Di Gerlando ; Giovanni Maria Foglia ; Matteo F. Iacchetti ; Roberto Perini
- Source: IET Power Electronics, Volume 6, Issue 9, p. 1927 –1938
- DOI: 10.1049/iet-pel.2013.0026
- Type: Article
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This study deals with the analytical modelling of the steady-state operation of a three-phase diode rectifier whose dc bus is connected to a constant voltage source. Such a system exhibits several operation modes that are fully investigated. Analytical expressions of the boundaries of each mode as well as the average dc and the rms ac currents are deduced as a function of the ac and dc parameters, including voltage drops across diodes. They allow us to evaluate the power delivered to the dc bus as well as the efficiency of the conversion in each mode of operation. These results can also be extended to practical rectifiers with bulk dc capacitors and allow for performing parametric analyses and optimisation in the design of drives or permanent magnet synchronous generators directly connected to a diode rectifier. The theoretical results are validated by experimental tests.
Improved performance of multilevel inverter-based distribution static synchronous compensator with induction furnace load
- Author(s): Parag Nijhawan ; Ravinder Singh Bhatia ; Dinesh Kumar Jain
- Source: IET Power Electronics, Volume 6, Issue 9, p. 1939 –1947
- DOI: 10.1049/iet-pel.2013.0029
- Type: Article
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Owing to the presence of large number of non-linear loads in the power distribution network, power quality levels are deteriorating. One such load is an induction furnace. The problem with the induction furnace load is that it introduces appreciable amount of harmonic distortion in the power system network. The performances of other loads connected in the power system network are also affected because of the presence of induction furnace load. In this study, the performance of a carrier phase shifted pulse-width modulation (PWM) multilevel inverter (five-level)-based distribution static synchronous compensator (DSTATCOM) is compared with that of a PWM inverter based-DSTATCOM with induction furnace load. The simulation results based on MATLAB/SIMULINK are presented to illustrate the effectiveness of multilevel inverter based-DSTATCOM for reducing harmonic distortion in the load current with induction furnace load in the distribution network.
Improved transient response using high-frequency feedback control circuit of the constant current ripple constant on-time with native adaptive voltage positioning design for voltage regulators
- Author(s): Wen-Wei Chen ; Jiann-Fuh Chen ; Tsorng-Juu Liang ; Sheng-Fu Hsiao ; Jian-Rong Huang ; Wei-Yuan Ting
- Source: IET Power Electronics, Volume 6, Issue 9, p. 1948 –1955
- DOI: 10.1049/iet-pel.2013.0020
- Type: Article
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Improved transient response using high-frequency feedback control (HFFC) circuit of the constant current ripple constant on-time (CCRCOT) with native adaptive voltage positioning design for voltage regulators (VRs) is proposed in this study. The concept uses the HFFC circuit to filter V out at the load transient to change the on-time width dynamically, preventing V out from dropping markedly. This proposal does not need an extra pin to achieve a quick response circuit. Finally, the multiphase VR with the HFFC circuit of the CCRCOT for the IC circuit of the proposed buck converter is implemented by experiment and simulation results to verify their viability and superiority.
Period-bubbling and mode-locking instabilities in a full-bridge DC–AC buck inverter
- Author(s): Deivasundari Parvathy Shankar ; Uma Govindarajan ; Kanimozhi Karunakaran
- Source: IET Power Electronics, Volume 6, Issue 9, p. 1956 –1970
- DOI: 10.1049/iet-pel.2013.0038
- Type: Article
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In this study, the non-linear dynamics of a full bridge DC–AC inverter controlled by fixed frequency pulse-width modulation which is widely used in solar energy systems is investigated. The main results are illustrated with the aid of time domain simulations obtained from an accurate non-linear time varying model of the system derived without making any quasi-static approximation. Results reveal that for high filter time-constants, the system loses stability via Hopf bifurcation and exhibits mode-locked periodic motion and for low filter time-constants, via period-doubling bifurcation resulting in period-bubbling structures and intermittent chaos. The mode-locked instability is also theoretically verified using Jacobian matrix derived from an averaged model and that of period-bubbling instability is verified using monodromy matrix based on Filippov's method of differential inclusions. Furthermore, extensive analyses are performed to study the mechanism of the emergence of intermittency and remerging chaotic band attractors (or Feigenbaum sequences) for variation in filter parameters and to demarcate the bifurcation boundaries. Phase portraits and Poincaré sections before and after the bifurcations are shown. Experimental results are also provided to confirm the observed bifurcation scenario.
Zero-voltage switching current-fed flyback converter for power factor correction application
- Author(s): Nha Trong Quang ; Huang-Jen Chiu ; Yu-Kang Lo ; Mohammed Mahmood Alam
- Source: IET Power Electronics, Volume 6, Issue 9, p. 1971 –1978
- DOI: 10.1049/iet-pel.2013.0042
- Type: Article
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Previous research on flyback power factor correction (PFC) converters exposes some inherent shortcomings, such as high-voltage spike on the metal oxide semiconductor field effect transistor (MOSFET), frequency variation, pulsating input current and hard switching operation. This study presents a new topology for PFC applications named zero-voltage switching (ZVS) current-fed flyback converter to not only achieve spike-free voltage, ZVS on the MOSFETs, but also improve the input current quality. By utilising quasi-z-source configuration, the voltage spikes on the MOSFET are effectively eliminated using only a capacitive clamper, resulting in no-loss consumption. Low-voltage MOSFETs with low on-resistance Rds (on) are used to improve the efficiency. In addition, by taking advantage of the average current mode control with the continuous conduction mode operation, the input current perfectly tracks the input voltage. To demonstrate the circuit's feasibility, a 100–140 V input, 28 V/5 A output laboratory prototype was built. The experimental results showed that the proposed topology completely eliminated the voltage spikes on the MOSFETs. The efficiency was improved using low Rds (on) MOSFETs, and ZVS was achieved. In summary, the proposed topology meets the high efficiency and high-input current quality requirements.
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