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- 实验方案
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A Novel Synchronous Current-Doubler Rectifier for LED Drivers Without Electrolytic Capacitors
摘要： High-brightness light-emitting diode (LED) lamps have attracted much attention because of their high efficiency, simple structure, energy conservation and environmental protection aspects, and long lifetime. Thus, an LED driver must have a long lifespan, high density, and compact space. However, conventional LED power supplies use an electrolytic capacitor as the storage capacitor in the holdup time, which has a short lifespan and occupies large space. In this paper, a novel synchronous current-doubler rectifier (SCDR) method is proposed as an LED driver. The reasonably designed circuit is used to control the output voltage ripple in the normal range without adding a complicated control circuit. The proposed topology is designed using few components, has no electrolytic capacitor, and has a low cost for high-output current LED driver applications. Circuit operating principles and detailed theoretical analysis are provided in this paper. A 200-W prototype has been established and tested, and the experimental results are presented to highlight the merits of the proposed circuit.
关键词： synchronous current-doubler rectifier (SCDR),LLC,light-emitting diode (LED),Electrolytic capacitor
更新于2025-09-19 17:13:59
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[IEEE 2019 44th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz) - Paris, France (2019.9.1-2019.9.6)] 2019 44th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz) - A Graphene Self-Switching Diode Bridge Rectifier
摘要： Here we present theory and measurements for a bridge rectifier formed from arrays of graphene self-switching diodes (GSSDs). Graphene’s extremely high carrier mobility allows GSSDs to work at THz frequencies, with the bridge rectifier structure allowing for full wave rectification of an AC signal. We derive an equation for the voltage output of a GSSD bridge rectifier, predicting a quadratic dependence on input current. This relationship is confirmed using AC and DC measurements. The fabricated rectifier has a high room temperature intrinsic responsivity of 3,230 V/W at low frequency and a low noise equivalent power of 7.0 pW/Hz1/2. Moving forward, similar devices using CVD graphene have been tested and shown to function with high responsivity.
关键词： THz frequencies,responsivity,bridge rectifier,self-switching diodes,graphene
更新于2025-09-16 10:30:52
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[IEEE IECON 2019 - 45th Annual Conference of the IEEE Industrial Electronics Society - Lisbon, Portugal (2019.10.14-2019.10.17)] IECON 2019 - 45th Annual Conference of the IEEE Industrial Electronics Society - The Research on Seamless Switching Control Strategy for Micro-grid Integrating Photovoltaic and Energy Storage
摘要： A large number of distributed photovoltaic power generations that are connected to the distribution network will have a serious impact on the power quality of the distribution network and load power security. Integrating energy storage and photovoltaic cells into the micro-grid can effectively improve the power quality of distribution network and the reliability of load consumption. This paper is a research on the seamless switching control strategy for micro-grid integrating photovoltaic and energy storage (MIPES). Firstly, it analyzes the boundary conditions of MIPES seamless switching control of grid-connected/islanded modes and studies the output characteristics of photovoltaic cells over a day. The DC bus voltage can be stabilized within a certain range to meet the requirements for MIPES seamless switching of grid-connected /islanded mode. Secondly, this paper analyzes the working characteristics of silicon controlled rectifier (SCR). The results show that when SCR is turned off naturally, the load voltage will rise sharply, affecting the safety of local load. Therefore, a control strategy for SCR switch forced shutdown is proposed to solve the problem of sharp rise of load voltage during grid-connected/islanded conversion of MIPES and to ensure the load security. Finally, relevant simulation studies are carried out to verify the rationality and effectiveness of the proposed control technology.
关键词： forced shutdown control,silicon controlled rectifier,seamless switching control,micro-grid integrating photovoltaic and energy storage
更新于2025-09-16 10:30:52
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[IEEE 2019 44th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz) - Paris, France (2019.9.1-2019.9.6)] 2019 44th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz) - High Performance Graphene Ballistic Rectifiers for THz detection
摘要： Although graphene can operate in the ballistic transport regime at room temperature, there are very few devices harnessing this property. Here we present a novel device called the ballistic rectifier which circumvents the problem of opening a bandgap in graphene. Based on the device theory, we propose four different asymmetric planar structures. All devices are working and show responsivity higher than 1,000 V/W at room temperature, with noise-equivalent power as low as 4.16 pW/Hz1/2. These properties make GBRs a suitable candidate for THz detection.
关键词： THz detection,noise-equivalent power,ballistic rectifier,responsivity,graphene
更新于2025-09-11 14:15:04
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A Turn-off Delay Controlled Bleeder Circuit for Single-Stage TRIAC Dimmable LED Driver With Small-Scale Implementation and Low Output Current Ripple
摘要： A single-stage TRIAC (TRIode for Alternating Current switch) dimmable LED (Light Emitting Diode) driver using a buck converter fed through a capacitor input rectifier provides many advantages such as small-scale implementation, low output current ripple, and stable dimming operation. This circuit topology, however, has a serious issue: a large inrush current to the smoothing capacitor. To solve this issue, this paper focuses on a bleeder circuit in the TRIAC dimmable LED driver. This paper presents the mechanism of the large inrush current issue and its relationship to a conventional bleeder circuit. Moreover, this paper proposes a turn-off delay controlled bleeder circuit. The proposed bleeder circuit is analyzed by using its discrete-time state-space model in order to set proper circuit parameters for inrush current reduction. Experimental results demonstrate the inrush current reduction by the proposed method, which leads to a 37 % reduction of maximum input current, as well as proper dimming operation and low output current ripple. The proposed method achieves further small-scale implementation, which enhances the advantages of the intended main circuit topology.
关键词： single-stage topology with capacitor input rectifier,LED driver,bleeder circuit,discrete-time state-space model,TRIAC dimmable
更新于2025-09-11 14:15:04
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[IEEE 2018 International Power Electronics Conference (IPEC-Niigata 2018 –ECCE Asia) - Niigata, Japan (2018.5.20-2018.5.24)] 2018 International Power Electronics Conference (IPEC-Niigata 2018 -ECCE Asia) - Series Resonant DC-DC Converter With Dual-Mode Rectifier for PV Microinverters
摘要： A new series resonant dc-dc converter is proposed for PV microinverters. Compared to the conventional series resonant converter (SRC), a dual-mode rectifier (DMR) is configured on the secondary side, which allows the proposed converter to achieve a wider gain range with a fixed-frequency phase-shift control. Moreover, the active switches and diodes are turned on with zero-voltage switching (ZVS) and off with zero-current switching (ZCS), respectively, thereby minimizing the switching losses. The operation principle is firstly detailed and then the converter characteristics are analyzed and compared. Finally, a 400-kHz 250-W converter prototype is built and tested to verify the advantages of the proposed converter.
关键词： PV microinverters,series resonant dc-dc converter,dual-mode rectifier,zero-voltage switching,zero-current switching
更新于2025-09-10 09:29:36
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A cm-Scale 2.4-GHz Wireless Energy Harvester With NanoWatt Boost Converter and Antenna- Rectifier Resonance for WiFi Powering of Sensor Nodes
摘要： The widespread use of WiFi in the 2.4-GHz ISM band creates the potential for RF powering using WiFi radios. This paper presents the design of a cm-scale RF-energy harvester including antenna, rectifier, and dc–dc boost converter for RF powering in the 2.4-GHz ISM band. The rectifier and boost converter are designed while considering cold-start operation and nanowatt-scale available power from the rectifier for RF incident power <?33 dBm. Low-power design in the power management unit and converter leads to ～1-nW quiescent power. The harvester implementation in 65-nm CMOS occupies 1.6 mm2 while the antenna occupies 1.27 cm2. The proposed design optimization approach leads to a sensitivity of ?33 dBm in cold start and ?36 dBm in the primary mode for 1-V output, translating to ～1.4× and ～2× improvement in range compared to prior art. Measurements using a commercial WiFi TX demonstrate the ranges of up to 1.25 m for 14-dBm output power with 1.3% TX duty-cycling in WiFi access-point mode, demonstrating the feasibility of powering sensors from RF power beacons in the 2.4-GHz ISM band as well as from background WiFi transmissions.
关键词： wireless powering,co-design,Antenna,ultralow power,WiFi charging,power management,sensitivity,boost converter,rectifier,RF,cold start,energy harvesting
更新于2025-09-09 09:28:46
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Enhanced Dickson voltage multiplier rectenna by developing analytical model for radio frequency harvesting applications
摘要： Radio frequency (RF) energy harvesting has experienced a rapid development recently because of the increasing number of RF transmitter sources. This article illustrates a novel analytical model for the voltage multiplier rectifier at 900 MHz. The model proposes a method of deriving the output characteristics of the rectifying circuits in terms of two main parameters; voltage and current. The design consists of seven stages of Dickson voltage multiplier rectifier. A Schottky diode HSMS 285C was used in the design. Equations for the model were developed. These equations were used to extract the values of output voltage and current. A simulation was optimized using advanced design systems. The system was correspondingly fabricated and tested for input power range of 1 × 10?5-1 × 10?1 W. Experimental results show that an output voltage of 5.45 V and current of 1.26 × 10?5 A are achieved at 10 dBm using a 10 kΩ load, achieving an efficiency of 37.82%.
关键词： analytical model,Dickson voltage multiplier rectifier,RF harvesting,rectenna
更新于2025-09-04 15:30:14