Full-bridge Series Resonant Converter Research Articles

A Novel MPPT Heating Control Strategy Applied to the Induction Heating System

This study proposes an induction heating system with maximum power-point tracking (MPPT) control strategy. The system architecture adopts a 1.3 kW full-bridge series resonant circuit with a step-down transformer and adjusts the operating frequency by a microcontroller unit to improve the heating efficiency. Secondly, the proposed MPPT control strategy based on induction heating uses the relationship between the operating frequency and the system heating temperature to find the operating frequency corresponding to the maximum power point (MPP) quickly. Then, an additional hill-climbing algorithm adjusting the duty cycle is applied to reach the duty cycle corresponding to the MPP. Under the simulation and actual experimental measurement, the traditional control strategy has 76% and 68% at 500 and 750 degrees, respectively, and it takes 320 s for the system to reach 750 degrees. By contrast, the proposed MPPT control strategy achieves 96% efficiency when the system heating temperature is 500 and 750 degrees, and it only takes 120 s to reach the system heating temperature to 750 degrees. The contribution of this study is that the traditional full-bridge series resonant converter is implemented for the proposed induction heating system, where the proposed MPPT control strategy applied to the proposed induction heating system significantly has high efficiency, high stability, and high heating speed advantages, which can be accurately controlled.

A Cost-Reliability Trade-Off Fault-Tolerant Series-Resonant Converter Combining Redundancy and Reconstruction

Adding redundant converters or switches are two common strategies to achieve fault-tolerant operation of converters. The former one is straightforward but costly, while the latter one is cost-effective but with sacrifice on the reliability as it only works for switches’ failure. Aiming to achieve a good trade-off between cost and reliability, a novel fault-tolerant full-bridge series-resonant converter (FB-SRC) which only needs a redundant half-bridge SRC (HB-SRC) to gain fault tolerance for all fault-prone components is proposed in this article. The proposed converter can keep working normally when short-circuit fault or open-circuit fault happens on switches, diodes, or the output filter capacitor. After fault occurs, the redundant HB-SRC converter will combine the remaining healthy part of original FB-SRC to reconstruct an input-parallel and output-series dual HB-SRC, which can maintain the rated output power with reduced cost. In the article, component's reliability of SRC is first analyzed. Then, operation and performance analysis of the proposed fault-tolerant converter is introduced in detail. As the voltage/current stresses of components are almost the same during the prefault and postfault operation, the converter design is simple. Finally, experimental results of a 500 W prototype are also given to verify the effectiveness.

Input voltage controlled full‐bridge series resonant converter for LED driver application

In this study, a phase shift controlled full-bridge series resonant converter (SRC) integrated with buck converters for light-emitting diode (LED) driver application is proposed. This LED driver supplies four LED loads simultaneously. The current through LED loads is controlled by phase shift control of the SRC, and its output is added to the input voltage. Zero-voltage switching (ZVS) switching of all the switches is achieved by operating the SRC at lagging power factor for all input voltage variations. As the only part of the output power is processed through the SRC and all the switches operating with ZVS, the efficiency of the converter is 95.7%, which is high. A 142 W LED driver is designed, and its performance is tested with PSPICE simulations and experimental prototype.

A Nonisolated Wide Input Series Resonant Converter for Automotive LED Lighting System

In this article, a reconfigurable nonisolated buck–boost (BB) integrated full-bridge series resonant converter (FBSRC) based light emitting diode (LED) driver is proposed for wide input voltage automotive lighting applications. The proposed LED driver is derived by the integration of BB operation with FBSRC. It can be reconfigured into three different resonant converter topologies such as BB integrated FBSRC, BB integrated half-bridge series resonant converter (BB-HBSRC), and conventional HBSRC and, hence, produces three levels of voltage gains. By transformation from one topology to other based on the input voltage range and with asymmetrical pulsewidth modulation control, it can operate for wide input voltage range while maintaining the soft switching. The main advantages of the proposed configuration are smooth transformation into three different topologies without any additional switching devices, no topological transitions within a switching cycle in steady state, use of simple proportional–integral controller, soft switching, and wider voltage gain with buck/boost operation. In addition, dimming control is also achieved using pulsewidth modulation technique. Detailed theoretical analysis of the proposed converter is presented. To verify the analysis and performance, a prototype of 22.7 W, 22.5 V LED driver is designed, simulated, and tested for a wide input voltage range of 18 to 120 V.

Analysis of high-voltage DC fuse’s ageing characteristics under the overload pulse current carrying mode and the caused short-circuit failure in series-resonant converter power source

As a key component in short-circuit protection, high-voltage fast DC fuse is broadly employed in high-power charge sources. In this paper, the overload pulse current carrying and ageing effect of high-voltage fast DC fuse which is used in series-resonant converter power source for short-circuit protection, is studied and analyzed. Main focus is on the mechanism of the DC1600V/32A fuse ageing and the following cut-out effect under the condition of high-frequency overload pulse current carrying. The effects on the full-bridge series-resonant converter charge source after the fuse ageing and breaking are also analyzed. The ageing under pulse currents is mainly caused by the repeated attacks of the heating-up and cooling on the fuse conductor. Four encountered stages of the fuse conductor under the high-frequency overload pulse current carrying are put forward in order, such as the linear ageing stage, the non-linear ageing stage, the fusing and arcing stage, and the arc extinguishing stage. In the linear ageing stage which plays as the available fuse life time, the fuse conductor carries the pulse currents normally and the temperature rise and fuse resistance Rf both increase linearly. When the increment ratio of Rf reaches 10%, the fuse starts to work in the non-linear ageing stage in which Rf increases nonlinearly and the series-resonant period of the charge circuit is prolonged. As the alternately opening switches in the H-bridge of the series-resonant converter are mismatched, the H-bridge is in short-circuit error, or the phenomena of the ‘hard switching’ and the failure for series-resonance occur. The circuit simulation and experimental results both demonstrate the H-bridge short-circuit error in series-resonant converter charge source is induced by the ageing of the fuse conductor under the overload pulse current carrying condition. In view of that, several ways for improving the fuse conductor ageing are put forward.

Highly Efficient Bidirectional Series-Resonant DC/DC Converter Over Wide Range of Battery Voltages

This article introduces a highly efficient bidirectional resonant dc/dc converter over wide range of battery voltages for vehicle-to-grid (V2G) capable electric vehicles (EVs). It operates as a pulsewidth-modulation (PWM) full-bridge series-resonant converter in the forward direction and a half-bridge resonant boost converter in the backward direction. One advantage of the proposed converter is that it has a wide voltage gain range in the backward operation. Also, it requires only six active switches. To achieve high efficiency, SiC mosfet s are used for two bottom switches in the primary side, because only these switches suffer hard switching turn- off in both forward and backward directions. Since it operates with fixed-frequency and with PWM control, the magnetic components and passive filters can be optimally designed with respect to the volume and the loss. Thus, the proposed converter achieves low-cost, high-conversion ratio, and high efficiency over a wide range of battery voltages. Detailed analysis of the converter operation is presented along with the design procedure. A 3.3-kW/400-V prototype of the proposed converter has been built to operate for 250–415 V primary source voltages and tested to demonstrate its circuit design.

An AC-AC High Frequency Pulse Density Modulated Full Bridge Series Resonant Converter for Induction Heating Application

<p class="Abstract">This paper deals with a new AC – AC single stage full bridge series resonant converter for induction heating application. The proposed system is simulated with high power density modulation technique to produce a output power of 1.8Kw.The main feature of the proposed converter is to reduce the total harmonic distortion produced in the output current for the switching frequency of 29Khz.Asymmetrical pulse density modulation technique is proposed to achieve maximum output power with less harmonic content. It is found that the THD of the proposed high power density modulated converter is 13.43%. Here, the validity of the proposed converter for domestic induction heating application is compared and summarized.</p>

An Active Voltage-Doubler Rectifier Based Hybrid Resonant DC/DC Converter for Wide-Input-Range Thermoelectric Power Generation

To develop thermoelectric power conditioning systems that are highly efficient over a wide range of input voltages and support medium-rated power, this paper introduces a hybrid resonant dc/dc converter using an active voltage-doubler rectifier. When the input voltage is higher than the preset nominal input voltage, the converter operates in the phase-shift full-bridge series-resonant converter mode, in which it achieves high efficiency by softly switching the primary-side switches and reducing the conduction loss. When the input voltage is lower than the nominal one, it operates in the resonant boost mode that boosts the resonant inductor current. By using the active voltage-doubler rectifier on the secondary side of the converter, we can build the converter with less number of active components. As a result, the proposed converter achieves, at low cost, high boost-ratio and high efficiency over a wide range of input voltages. A detailed analysis of the converter operation is presented along with the design procedure. At 35-55 V, a 600-W/360-V prototype of the proposed converter has been built and tested to demonstrate its effectiveness.

Pulse density modulation controlled converter for PV systems

This paper presents a pulse density modulation (PDM) controlled resonant converter for photo-voltaic (PV) system. Maximum power point of the PV generation system is tracked by deleting some control pulses of full bridge series resonant converter. Phase of the converter current is controlled by phase locked loop circuit and zero current switching is achieved for different irradiation conditions. Perturb and observe method is used for maximum power point tracker and designed system is experimentally tested by solar array simulator for 600 W PV power with 116 kHz PDM-MPPT controlled resonant converter.

ZVS Full Bridge Series Resonant Boost Converter with Series-Connected Transformer

This paper presents a study on a new full bridge series resonant converter (SRC) with wide zero voltage switching (ZVS) range, and higher output voltage. The high frequency transformer is connected in series with the LC series resonant tank. The tank inductance is therefore increased; all switches having the ability to turn on at ZVS, with lower switching frequency than the LC tank resonant frequency. Moreover, the step-up high frequency (HF) transformer design steps are introduced in order to increase the output voltage to overcome the gain limitation of the conventional SRC. Compared to the conventional SRC, the proposed converter has higher energy conversion, able to increase the ZVS range by 36%, and provide much higher output power. Finally, the a laboratory prototypes of the both converters with the same resonant tank parameters and input voltage are examined based on 1 and 2.2 kW power respectively, for veryfing the reliability of the performance and the operation principles of both converters.

Hybrid-Type Full-Bridge DC/DC Converter With High Efficiency

This paper presents a hybrid-type full-bridge dc/dc converter with high efficiency. Using a hybrid control scheme with a simple circuit structure, the proposed dc/dc converter has a hybrid operation mode. Under a normal input range, the proposed converter operates as a phase-shift full-bridge series-resonant converter that provides high efficiency by applying soft switching on all switches and rectifier diodes and reducing conduction losses. When the input is lower than the normal input range, the converter operates as an active-clamp step-up converter that enhances an operation range. Due to the hybrid operation, the proposed converter operates with larger phase-shift value than the conventional converters under the normal input range. Thus, the proposed converter is capable of being designed to give high power conversion efficiency and its operation range is extended. A 1-kW prototype is implemented to confirm the theoretical analysis and validity of the proposed converter.

Adjustable Frequency–Duty-Cycle Hybrid Control Strategy for Full-Bridge Series Resonant Converters in Electric Vehicle Chargers

In this paper, an effective output voltage control method using adjustable frequency-duty-cycle hybrid control is presented. By using the proposed method, the operating performance of the full-bridge series resonant dc-dc converter applied to the onboard charger in electric vehicles under the constant-voltage charge mode is improved. The proposed control method improves the system efficiency of the charger up to 4% for light load conditions compared with the conventional control method without any extra hardware. A theoretical analysis is described along with a loss analysis in detail, and the validity of the proposed method is verified by experiment with a 3.3-kW prototype onboard charger.

Modeling and Simulation of Full-Bridge Series Resonant Converter Based on Generalized State Space Averaging

The small signal modeling technique based on the generalized state space averaging method is applied to single phase full-bridge resonant DC/DC converter .According to the simulation, the frequency characteristic curve is obtained from MATLAB, this paper analyzes the influence of the duty ratio, input voltage to frequency characteristics, then builds a closed loop simulation circuit with PSIM software, the simulation results show that, the small signal model has good controllability and anti disturbance resistance, generalized state space averaging method is more accurate to series resonant converter modeling.

Comparative Analysis of Charging Modes of Series-Resonant Converter for an Energy Storage Capacitor

This paper discusses charging modes of series-resonant converter (SRC) for an energy storage capacitor in terms of charging time, losses of switch, normalized peak resonant current, normalized peak resonant voltage, and switch utilization in three operational modes. Principles of operation on the full-bridge SRC with capacitor load are explained, and charging characteristics in discontinuous and continuous operational modes are analyzed. Based on the analysis and the simulation focused on the aforementioned five performance indexes, <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ms</i> = 0.5 is evaluated to be the optimized operating frequency ratio for charging an energy storage capacitor. A 1.8-kJ/s SRC prototype is assembled with the TI 28335 DSP controller and a 40-kJ 7-kV capacitor. Design rules based on the comparative analysis are verified by experiment.

에너지저장 커패시터의 최적 충전을 위한 직렬공진형 컨버터의 운용 모드 비교

In this paper, charging modes of series resonant converter for a high voltage energy storage capacitor are compared in terms of charging time, peak resonant current, normalized peak resonant current and voltage in each operation mode. Operating principles of the full bridge series resonant converter with capacitor load are explained and analyzed in discontinuous and continuous operation mode. Based on the analysis and simulation result, 0.6ω_r<ω_s<0.75ω_r and 1.3ω_r<ω_s<1.4ω_r are evaluated to the best range of switching frequency for charging of an high voltage energy storage capacitor. 1.8 kJ/s SRC prototype is assembled with TI 28335 DSP controller and 40 kJ, 7 kV energy storage capacitor. Design rules based on the comparative analysis are verified by experiment.

Phase-Shifted Full-Bridge Series-Resonant DC-DC Converters for Wide Load Variations

This paper presents the design of a phase-shifted full-bridge series resonant converter (PS-FB SRC). The proposed FB SRC features a novel two-mode operation. It is operated in series resonant mode at normal loads. The switching frequency is varied to regulate the output voltage. The fixed-frequency phase-shifted pulse width modulation, on the other hand, is used to adjust the effective duty cycle and regulate the output voltage at light loads. The proposed converter exhibits high conversion efficiency for wide-range load conditions. The relationships among the voltage gain, the switching frequency, and the effective duty cycle are discussed and analyzed. Finally, a 48-V/42-A prototype is implemented. Experiments are conducted to verify the theoretical analysis.

Bidirectional Switch Commutation for a Matrix Converter Supplying a Series Resonant Load

This paper describes a bidirectional switch commutation strategy for a three-phase to two-phase matrix converter supplying a series resonant load. Classical modulation techniques are not applicable because of the needed high output frequencies. This fact, together with the different topology compared to classical three-phase to three-phase matrix converters, makes a new investigation of commutation principles necessary. The paper shows that the three-phase to two-phase resonant matrix converter can be compared with the full-bridge series-resonant converter. Thus, the commutation of the full-bridge series-resonant converter gives the conditions for the bidirectional switch commutation at the matrix converter. One of the main benefits of the derived strategy is the minimization of commutation steps independent of the load current sign.

Bidirectional Switch Commutation for a Matrix Converter Supplying a Series Resonant Load

This paper describes a bidirectional switch commutation strategy for a three-phase to two-phase matrix converter supplying a series resonant load. Classical modulation techniques are not applicable because of the needed high output frequencies. This fact, together with the different topology compared to classical three-phase to three-phase matrix converters, makes a new investigation of commutation principles necessary. The paper shows that the three-phase to two-phase resonant matrix converter can be compared with the full-bridge series-resonant converter. Thus, the commutation of the full-bridge series-resonant converter gives the conditions for the bidirectional switch commutation at the matrix converter. One of the main benefits of the derived strategy is the minimization of commutation steps independent of the load current sign.

Application of axisymmetric modelling to integrated LCT structure of series‐resonant converter

AbstractThe aim of this paper is to present a low‐cost solution for low‐power applications. A high‐frequency AC to DC converter respecting the EN 61000‐3‐2 standard and suitable for application in the power range of 300 W is presented. Its topology is based on a full‐bridge series‐resonant converter that operates below half the resonant frequency. The converter features zero‐current for both turn‐on and turn‐off and reduces the switching current for the output rectifier. These advantages make the series‐resonant topology suitable for operation at high frequency. A method for the design of an integrated LCT structure (Inductor–Capacitor–Transformer) is presented. Also, results of the application of a newly developed FEA (Finite Elements Analysis) formulation for the constructed LCT prototype are presented. It is shown that the necessary capacitance can be achieved by using a bifilar primary and the leakage inductance of the transformer replaces the physical inductor. Finally, two PFC (Power Factor Correction) series‐resonant converters, using integrated and discrete LCT, were built, tested and compared. Copyright © 2004 John Wiley &amp; Sons, Ltd.

Modeling and analysis of wound integrated LCT structure for single stage resonant PFC rectifier

In the literature, several AC/DC converters are studied and presented. All kinds of topologies and techniques are covered under this topic. This includes single-switch, half-bridge and full bridge topologies as well as hard, quasi-resonant and resonant switching. Different techniques are also developed to control these converters ensuring high power factor. The aim of this paper is to present a low-cost solution for low-power applications. A high-frequency AC to DC converter that respects the EN 61000-3-2 standard and is suitable for applications in the power range of 300 W, is presented. Its topology is based on a full-bridge series-resonant converter that operates below half the resonant frequency. The converter features zero-current for both turn-on and turn-off and reduces the switching current for the output rectifier. These advantages make the series-resonant topology suitable for operation at high frequency. Thus, electromagnetic integration of the LCT network (inductor-capacitor-transformer) is successfully applied owing to the fact that the inductor and the capacitor values are relatively small at this range of frequency. Computer simulation and experimental results are presented.