- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Design of Efficient Resonator-Enhanced Electro-Optic Frequency Comb Generators
摘要： This paper proposes a direct double-frequency ripple current control in a single-phase high-power fuel cell converter that can achieve low-frequency ripple-free input current without using large electrolytic capacitors. To eliminate the double-frequency ripple current disturbance introduced by the single-phase inverter load, a proportional–resonant controller is developed to achieve an extra high control gain at designed resonant frequency. This high gain can be viewed as the virtual high impedance for blocking the double-frequency ripple energy propagation from inverter load to fuel cell stack. More particularly, the proposed control system can realize the utilization of all capacitive ripple energy sources in the system by regulating all the capacitors to have large voltage swing. In addition, this voltage swing is synchronized to keep real-time balancing of the transformer primary- and secondary-side voltages. As a result, the zero-voltage-switching operation for all switching devices in the dc–dc stage can be guaranteed. The controller design guidelines are derived based on the system small-signal model. The experimental results are presented to validate the theoretical analysis and proposed technology.
关键词： Current-fed three-phase dc–dc converter,fuel cell,direct double-frequency ripple current control,electrolytic capacitor free,zero voltage switching (ZVS)
更新于2025-09-23 15:21:01
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[IEEE 2019 IEEE Asian Solid-State Circuits Conference (A-SSCC) - Macau, Macao (2019.11.4-2019.11.6)] 2019 IEEE Asian Solid-State Circuits Conference (A-SSCC) - A 0.7mm <sup>2</sup> 8.54mW FocusNet Display LSI for Power Reduction on OLED Smart-phones
摘要： A discontinuous conduction mode (DCM) zero-voltage switching (ZVS) scheme for a class-D power amplifier (PA) for wireless power transfer is presented. The sizes of the ZVS inductor and capacitor are reduced by 7.5 and 5 times and ZVS is achieved even subject to PA supply voltage and output current variations. The class-D PA was fabricated with a 0.35 μm high-voltage CMOS process. The ZVS LC resonant tank consists of a 39 nH inductor and a 200 nF capacitor. The switching frequency was 6.78 MHz and the supply voltage was 20 V. Measurement results show that the PA delivered an output power of 7.18 W with a peak efficiency of 87.0%.
关键词： power amplifier,wireless power transfer,Class-D,zero-voltage switching (ZVS)
更新于2025-09-23 15:21:01
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[IEEE 2019 International Semiconductor Conference (CAS) - Sinaia, Romania (2019.10.9-2019.10.11)] 2019 International Semiconductor Conference (CAS) - Voltage Controlled Oscillator for Small-Signal Capacitance Sensing
摘要： SiC MOSFETs are applied to constitute a three-phase, 5-kW LLC series resonant dc/dc converter with isolation transformers. A switching frequency of around 200 kHz for the transistors successfully reduces the volume of these isolation transformers, whereas insulated-gate bipolar transistors (IGBTs) are not capable of achieving such a high switching speed. The high-voltage tolerance of SiC MOSFETs, 1200 V, enables increasing the input voltage up to 600 V. High-voltage tolerance, on the other hand, is not compatible with low on-resistance for Si MOSFETs. A three-phase circuit topology is used to achieve up to 5 kW of power capacity for the converter and reduce per-phase current at the same time. Current-balancing transformers among these three phases effectively suppress a maximum peak current from arising in the circuit, a technique that miniaturizes the input and output capacitances. The conversion efficiency of the converter reaches 97.6% at 5-kW operation.
关键词： SiC MOSFETs,zero-voltage switching (ZVS),Current-balancing transformers,zero-current switching (ZCS),three phase,LLC resonant converter
更新于2025-09-19 17:13:59
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[IEEE 2018 2nd IEEE International Conference on Power Electronics, Intelligent Control and Energy Systems (ICPEICES) - Delhi, India (2018.10.22-2018.10.24)] 2018 2nd IEEE International Conference on Power Electronics, Intelligent Control and Energy Systems (ICPEICES) - A Modified Perturb & Observe Algorithm For Maximum Power Point Tracking With Zero Voltage Switching Buck Boost Converter in Photovoltaic System
摘要： The conventional perturb and observe algorithm used for maximum power point tracking of PV system suffers from major drawbacks such as steady state oscillation around final maximum power point and loss of tracking direction i.e. divergence from actual maximum power point for rapid change in insolation. Both these problems result in significant power loss as the PV system operating point is getting diverted from actual maximum power point. As Buck-Boost converter plays an important role while changing the operating point of PV panel, it contributes to significant amount of power loss in the form of switching loss, conduction loss etc. This paper proposes a method to avoid the above given shortcomings of perturb & observe algorithm. Major focus is given on the designing of Buck-Boost converter as to date nobody has taken into consideration the losses occurring in the converter even though converter forms an integral part of the MPPT set up. The losses occurring in the conventional buck boost converter have been computed and its effect on the efficiency of MPPT system is investigated. The soft-switched buck boost converter for PV applications is designed so as to minimize the losses taking place in converter.
关键词： Buck-boost converter,Perturb and observe (P&O),Photo voltaic (PV),Soft switching,Zero voltage switching (ZVS)
更新于2025-09-16 10:30:52