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Half bridge ZVS DC-DC converter with DCS PWM active clamp technique  [cached]
JANAPATI SIVAVARA PRASAD
International Journal of Power Electronics and Drive Systems , 2012, DOI: 10.11591/ijpeds.v2i4.400
Abstract: Half bridge (HB) dc–dc converter is an attractive topology for middle power level applications owing to its simplicity. This paper presents a new control scheme, to be known as duty-cycle shifted PWM (DCS PWM) control, is proposed and applied to the conventional HB dc–dc converters to achieve ZVS for one of the two switches without adding extra components and without adding asymmetric penalties of the complementary control. The concept of this new control scheme is shifting one of the two symmetric PWM driving signals close to the other, such that ZVS may be achieved for the lagging switch due to the shortened resonant interval. Moreover, based on the DCS PWM control, an active clamp branch comprising an auxiliary switch and a diode is added across the isolation transformer primary winding in the half bridge converter to achieve ZVS for the other main switch by utilizing energy stored in the transformer leakage inductance. Moreover, the auxiliary switch also operates at ZVS and ZCS conditions. In addition, the proposed topology with DCS PWM control eliminates the ringing resulting from the oscillation between the transformer leakage inductance and the switches junction capacitances during the off-time period. Therefore, the proposed converter has a potential to operate at higher efficiencies and switching frequencies.
Performance Analysis of PI and Fuzzy Control for Modified LCC Resonant Converter Incorporating Boost Converter  [PDF]
N. Madhanakkumar, T. S. Sivakumaran
Circuits and Systems (CS) , 2016, DOI: 10.4236/cs.2016.76072
Abstract: In this paper, the modified LCC type of series-parallel Resonant Converter (RC) was designed and state-space modeling analysis was implemented. In this proposed converter, one leg of full bridge diode rectifier is replaced with Synchronous Rectifier (SR) switches. The proposed LCC converteris controlled using frequency modulation in the nominal state. During hold-up time, the SRswitches control is changed from in-phase to phase-shifted gate signal to obtain high DC voltage conversion ratio. Furthermore, the closed loop PI and fuzzy provide control on the output side without decreasing the switching frequency. The parameter such as conduction loss on primary and secondary side, switching loss, core and copper also reduced. Simultaneously, the efficiency is increased about 94.79 is realized by this scheme. The proposed converter with an input of 40 V is built to produce an output of 235 V with the help of ZVS boost converter[1]even under line and load disturbances. As a comparison, the closed loop fuzzy controller performance is feasible and less sensitive than PI controller.
Closed loop control of ZVS half bridge DC-DC converter with DCS PWM Control  [cached]
JANAPATI SIVAVARA PRASAD
International Journal of Power Electronics and Drive Systems , 2012, DOI: 10.11591/ijpeds.v2i4.401
Abstract: The main drawback of the conventional symmetric control is that both primary switches in the converter operate at hard switching condition. Moreover, during the off-time period of two switches, the oscillation between the transformer leakage inductance and junction capacitance of the switches results in energy dissipation and electromagnetic interference (EMI) emissions due to reverse recovery of MOSFETs body diodes. The asymmetric (complementary) control was proposed to achieve ZVS operation for HB switches. However, asymmetric stresses distribution on the corresponding components may occur due to the asymmetric duty cycle distribution for the two primary switches. A new control scheme, to be known as duty-cycle shifted PWM (DCS PWM) control, is proposed and applied to the conventional HB dc–dc converters to achieve ZVS for both the switches without adding extra components and without adding asymmetric penalties of the complementary control. The concept of this new control scheme is shifting one of the two symmetric PWM driving signals close to the other, such that ZVS may be achieved for the lagging switch due to the shortened resonant interval. Moreover, based on the DCS PWM control, a new half-bridge topology is proposed to achieve ZVS for both the main switches and auxiliary switch by adding an auxiliary switch and diode in the proposed half bridge. ZVS for the switch is achieved by utilizing the energy trapped in the leakage inductance. There are two control schemes. One is open loop and the other is closed loop. In open loop scheme, the given dc-dc converter is operating under disturbance. This disturbance effect is eliminated in closed loop scheme.
SIMULATION AND ANALYSIS OF PWM-CONTROLLED QUASI-RESONANT CONVERTER FOR DRIVES
Ms. Ashly Mary Tom,Helen Priscilla A.S.
Indian Streams Research Journal , 2012,
Abstract: This paper presents the development of a new resonant capacitor assisted pulse width modulationcontrolled quasi resonant converter with an auxiliary circuit which does the load regulation by controlling the ripple of the resonant voltage. This resonant converter is simulated through MATLAB/SIMULINK. This newly developed quasi resonant DC-DC converter can regulate its DC output under a principle of constant frequency soft switching commutation by a controllable PWM duty cycle control scheme. The ripple of the resonant voltage across the primary resonant capacitor is controlled with a bidirectional auxiliary circuit, while the main switches are operated at a fixed duty ratio and fixed switching frequency. The operating performances of the newly proposed PWM-controlled quasi resonant converter are represented based on simulation results from an applications point of view.
Regeneration of ZVS converter with Resonant inductor  [cached]
J.Sivavara Prasad,Ch.Sai Babu,Y.P. Obelesh
International Journal of Power Electronics and Drive Systems , 2011, DOI: 10.11591/ijpeds.v1i1.71
Abstract: This paper presents an analysis of the regeneration of zero-voltage-switching converter with resonant inductor, quasi-resonant converters, and full-bridge zero-voltage-switched PWM Converter. The design of a clamping circuit considering a saturable resonant inductor is presented and compared with the design of a clamping circuit with a linear resonant inductor. A diode model with reverse recovery is employed to simulate the effects.
Control of a resonant d.c.-link converter for a.c. motor drives
Astrid Petterteig
Modeling, Identification and Control , 1992, DOI: 10.4173/mic.1992.4.2
Abstract: This paper presents the control of the resonant d.c.-link converter for a.c. motor drives. This is a low loss converter with higher efficiency than a conventional PWM converter, but it requires complex control. It needs a special control of the resonant d.c.-link voltage in addition to the discrete control of the a.c. side currents. Simulations show how the control of the a.c. currents, the modulation principle, influences the overall performance of the converter.
宽范围输入输出电压LCC谐振变换器的分析设计  [PDF]
刘国梁,李新,伍梁,李振宇,陈国柱
- , 2018, DOI: 10.3785/j.issn.1008-973X.2018.09.017
Abstract: 文章对电流连续工作模式(CCM)下LCC谐振变换器的工作模态进行了分析,在此基础上采用基波近似法对LCC谐振拓扑进行了简化,推导出LCC谐振变换器的基波纯阻性和基波容性等效电路,建立了与开关频率、负载及变换器增益有关的数学模型.结合模型,提出了宽范围输入输出电压LCC谐振拓扑的设计方法,基于此方法结合一套电源设计指标设计了一组谐振参数.通过仿真验证了所设计的LCC谐振变换器在宽范围输入输出电压条件下可实现全负载范围的软开关,满足设计指标,证明了模型和设计方法具有较高精准度和良好应用价值.
Abstract: The paper makes a full analysis for the working mode of the LCC resonant converter in the continuous current mode (CCM). On this basis, further researches need to be completed which include analyzing the LCC resonant topology using Fundamental Wave Approximation, deducing its fundamental wave equivalent circuit of pure resistance and capacitive, and building its mathematical model related with the switch frequency, load and convert gain. On the grounds of the model, a design method of LCC resonant converter operating under a wide range input and output voltage is proposed, and a list of resonant parameters is designed for a set of power supplies based on the method. Then, Simulation results demonstrate that the designed LCC resonant converter can achieve the full-load range soft-switching under a wide range of input and output voltage and meet the design specifications. Besides, it proves that the model and the design method have high accuracy and good application value.
ZAD strategy with lateral PWM applied to a Boost converter  [cached]
Andrés Amador,Simeon Casanova,Julián Hurtado,Gerard Olivar
Matemáticas : Ense?anza Universitaria , 2012,
Abstract: In this paper we show some results about the dynamics of a Boost converter when it is controlled by lateral PWM (Pulse Width Modulator) and ZAD (Zero Average Dynamics) strategy. Different nonlinear phenomena like bifurcations and chaos are reported when the parameters associated to the system are varied. Finally, chaos present in the converter is controlled using FPIC (Fixed Point Induced Control) and TDAS (Time-Delay Autosynchronization) techniques.
HIGH EFFICIENCY BRIDGELESS PWM CUK CONVERTER WITH SOFT SWITCHING TECHNIQUE
ANJAN KUMAR SAHOO, SARIKA KALRA, NITIN SINGH
International Journal of Electrical, Electronics and Data Communication , 2013,
Abstract: High efficiency bridgeless single-phase ac-dc PWM cuk converter with soft-switching (ZVS) technique is proposed. This paper emphasizes more on the converter efficiency. The conduction losses and input current harmonics of the proposed converter is very less due to the absence of the input diode bridge and also during each switching cycle, only two semiconductor switches are present in the current path unlike other conventional Cuk converters. Soft switching (ZVS)technique is applied by using an auxiliary circuit to improve the efficiency of the proposed converter. Output voltage regulating control technique is provided to regulate the output which also ultimately improves the efficiency. Power factor is almost unity due to less input current harmonics. The circuit configuration, principle of operation, design procedure and simulation results are presented.
Dynamics of IGBT based PWM Converter A Case Study
Navpreet Singh Tung,Amit Bhardwaj,Tarun Mittal,Vijay Shukla
International Journal of Engineering Science and Technology , 2012,
Abstract: Optimizing the efficiency and dynamics of power converters is a critical tradeoff in power electronics. The increase of switching frequency can improve the dynamics of power converters, but theefficiency may be degraded as well as the switching losses. As power semiconductor devices like diodes, MOSFETS, IGBTs, Thyristors, BJTs have their own characterstics and dynamic responses. It is desired toanalyze and observe the dynamics of different semiconductor devices before they actually employed in the model. Inclusion of different PWM techniques help in the removal of power line interferences like harmonic losses, unwanted ripples, chopped frequencies, spikes. In this paper, we have studied and analyzed the dynamics of IGBT based PWM converter with subjected to different conditions like transient state, steady state feeding the RLC load. Snubber circuits are used to reduce the switching losses. The IGBT based PWM converter reflects the better dynamics with improved efficiency and reduced harmonics as compared to some other power semiconductor devices when FFT is performed and subjected to standard parameterized RLC load understeady state and transient analysis.
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