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Novel forward mode AC/AC converters with high frequency link 被引量:1
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作者 李磊 陈道炼 胡育文 《Journal of Southeast University(English Edition)》 EI CAS 2003年第3期246-249,共4页
A circuit configuration and a circuit topologic family of the novel forward mode AC/AC converters with high frequency link are presented. The circuit configuration is constituted of input cycloconverter, high frequenc... A circuit configuration and a circuit topologic family of the novel forward mode AC/AC converters with high frequency link are presented. The circuit configuration is constituted of input cycloconverter, high frequency transformer, output cycloconverter, input and output filters. The circuit topologic family includes eight circuit topologies, such as full-bridge-full-wave mode, etc. The bi-polarity phase-shifted control strategy and steady principles are thoroughly investigated. The output characteristics are obtained. By using the bi-polarity phase-shifted control strategy with phase-shifted control between the output cycloconveter and the input cycloconverter, commutation overlap period of the output cycloconverter, and polarity selection of the output filtering inductance current and the input voltage, the leakage inductance energy and the output filtering inductance current are naturally commutated, and surge voltage and surge current of the cycloconverters are overcome. The converters have such advantages as simple topology, two-stage power conversions(LFAC/HFAC/LFAC), bi-directional power flow, high frequency electrical isolation, good output waveforms, and strong ability to stabilize voltage. The converters lay key technical foundation on a new-type of regulated sinusoidal AC power supplies and electronic transformers. The correction and advancement of the converters are well verified by a principle test. 展开更多
关键词 forward mode high frequency link AC/AC converter bi-polarity phase-shifted control CYCLOconverter
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Zero-voltage switching converter absorbing parasitic parameters for super high frequency induction heating 被引量:1
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作者 Zheng-shi WANG Hui-ming CHEN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第4期564-571,共8页
This paper presents a novel mega-Hz-level super high frequency zero-voltage soft-switching converter for induction heating power supplies. The prominent advantage of this topology is that it can absorb both inductive ... This paper presents a novel mega-Hz-level super high frequency zero-voltage soft-switching converter for induction heating power supplies. The prominent advantage of this topology is that it can absorb both inductive and capacitive parasitic components in the converter. The switch devices operate in a zero-voltage soft-switching mode. Consequently, the high voltage and high current spikes caused by parasitic inductors or capacitors oscillation do not occur in this circuit, and the high power loss caused by high frequency switching can be greatly reduced. A large value inductor is adopted between the input capacitor and the switches, thus, this novel converter shares the benefits of both voltage-type and current-type circuits simultaneously, and there are no needs of dead time between two switches. The working principles in different modes are introduced. Results of simulation and experiments operated at around 1 MHz frequency verify the validity of parasitic components absorption and show that this convener is competent for super high frequency applications. 展开更多
关键词 Induction heating Super high frequency Soft-switching converter Parasitic parameters
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Development of OPTO-LDR coupled timer based voltage to frequency converter 被引量:1
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作者 Akash Kumar Anindya Debnath +4 位作者 Antar Banik Kabirul Islam Mondal Partha Pratim Biswas Rik Bhattacharyya T K Maiti 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2017年第1期17-20,共4页
This paper describes the development of a timer based voltage to frequency converter(V FC).Timer LM555is used in astable multivibrator mode with two OPTO-LDRs(light dependent resistors)in the circuitry.The frequency o... This paper describes the development of a timer based voltage to frequency converter(V FC).Timer LM555is used in astable multivibrator mode with two OPTO-LDRs(light dependent resistors)in the circuitry.The frequency of timer output waveform which is measured using a digital storage oscillator(DSO)is almost linearly proportional to the applied input voltage.Hence we obtain a linear relationship between the frequency of timer output waveform and the input voltage.Because of its quasi-digital output,the main advantages of this developed converter are linear input-output relationship,small size,easy portabilityand high cost performance.In addition,the timer output waveform can be directly interfaced with personal computer or microprocessor/microcontroller for further processing of the input voltage signal without intervening any analog-to-digital converter(ADC). 展开更多
关键词 timer LM 555 astable multivibrator light emitting diode (LED) light dependent resistor (LDR) voltage to frequency converter (V FC) digital storage oscillator (DSO)
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Analysis of Soft-Switched High Frequency AC-AC Converter for Induction Motor Drive
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作者 马宪民 B.K.Bose 《International Journal of Mining Science and Technology》 SCIE EI 2000年第1期49-53,共5页
The systematic mathematical analysis of the high frequency soft-switched AC-AC converter is proposed for variable frequency induction machine load in this paper. Both PWM and square-wave modes of operation have been c... The systematic mathematical analysis of the high frequency soft-switched AC-AC converter is proposed for variable frequency induction machine load in this paper. Both PWM and square-wave modes of operation have been considered. The frequency relation and phase unbalance problem due to discrete time integral half-cycle switching has been discussed in the beginning. Then, generalized Fourier series have been derived for output voltage, output current and supply current in two modes.The analytical results help to understand tbe converter characteristics, design optimally a convertermachine system of arbitrary capacity considering the various trade-off parameters. 展开更多
关键词 HIGH frequency soft-switch AC-AC converterS FOURIER SERIES
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Phasor Control of Converter Output Voltage for Frequency Regulation
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作者 Masahide Hojo Ryo Ikeshita +1 位作者 Yoshinobu Ueda Toshihisa Funabashi 《Journal of Power and Energy Engineering》 2014年第7期19-27,共9页
The synchronizing torque of a power system may be weakened by increasing installation of static power converters accompanied by renewable energy resources because they used to trade their favorable active power by syn... The synchronizing torque of a power system may be weakened by increasing installation of static power converters accompanied by renewable energy resources because they used to trade their favorable active power by synchronizing their output voltage with the one at the point of common coupling. In the circumstances, a concept of Virtual Synchronous Machine (VSM) is proposed, where the self-commutated power converters are emulating synchronous generators. This paper describes a converter control to contribute to enhancing the synchronizing torque. The proposed control is similar to the VSM but it simply realizes active power trades among power generation units including converter-based generators by modulating phase angles of their output voltages. Therefore, it can provide an effective support to regulate the system frequency where the total rated power of the converter-based generators increases as much as the one of conventional rotating generators like a microgrid. This paper especially focuses on its robustness where the number of converter-based generators is increased or they are dispersed in the power network. The effectiveness is verified by simulation study based on instantaneous values. 展开更多
关键词 Self-Commutated Power converter SYNCHRONOUS GENERATOR frequency CONTROL VOLTAGE PHASOR
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A linear-to-circular polarization converter based on I-shaped circular frequency selective surfaces
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作者 吴家梁 林宝勤 +1 位作者 达新宇 吴凯 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第9期184-189,共6页
In this paper, a linear-to-circular polarization converter using a three-layer frequency selective surface based on Ishaped circular structure resonant is presented and investigated. Numerical simulations exhibit that... In this paper, a linear-to-circular polarization converter using a three-layer frequency selective surface based on Ishaped circular structure resonant is presented and investigated. Numerical simulations exhibit that when the normal ypolarized waves impinge on this device propagating towards +z direction, the two orthogonal components of the transmitted waves have a 90° phase difference as well as the nearly equal amplitudes at the resonant frequency of 7.04 GHz, which means that the left-hand circular polarization is realized in transmission. For validating the proposed design, a prototype which consists of 25 × 25 elements has been designed, manufactured and measured. The measured results are in good agreement with the simulated ones, showing that the polarization conversion transmission is over-3 dB in the frequency range of 5.22–8.08 GHz and the axial ratio is below 3 dB from 5.86 GHz to 7.34 GHz. 展开更多
关键词 polarization converter metasurface frequency selective surface
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Bifurcation and chaos in high-frequency peak current mode Buck converter
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作者 常昌远 赵欣 +1 位作者 杨帆 吴承恩 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第7期171-178,共8页
Bifurcation and chaos in high-frequency peak current mode Buck converter working in continuous conduction mode(CCM) are studied in this paper. First of all, the two-dimensional discrete mapping model is established.... Bifurcation and chaos in high-frequency peak current mode Buck converter working in continuous conduction mode(CCM) are studied in this paper. First of all, the two-dimensional discrete mapping model is established. Next, reference current at the period-doubling point and the border of inductor current are derived. Then, the bifurcation diagrams are drawn with the aid of MATLAB. Meanwhile, circuit simulations are executed with PSIM, and time domain waveforms as well as phase portraits in i_L–v_C plane are plotted with MATLAB on the basis of simulation data. After that, we construct the Jacobian matrix and analyze the stability of the system based on the roots of characteristic equations. Finally, the validity of theoretical analysis has been verified by circuit testing. The simulation and experimental results show that,with the increase of reference current I_(ref), the corresponding switching frequency f is approaching to low-frequency stage continuously when the period-doubling bifurcation happens, leading to the converter tending to be unstable. With the increase of f, the corresponding Irefdecreases when the period-doubling bifurcation occurs, indicating the stable working range of the system becomes smaller. 展开更多
关键词 peak current mode Buck converter high frequency bifurcation chaos
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Model predictive control of three-level active front-end converter with low switching frequency
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作者 YANG Li WANG Lang-zhu +1 位作者 FENG Bo WANG Hong-lin 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2018年第2期153-159,共7页
In medium voltage-high power(MV-HP)applications,the high switching frequency of power converter will result in unnecessary energy losses,which directly affect efficiency.To resolve this issue,a novel finite control se... In medium voltage-high power(MV-HP)applications,the high switching frequency of power converter will result in unnecessary energy losses,which directly affect efficiency.To resolve this issue,a novel finite control set-model predictive control(FCS-MPC)with low switching frequency for three-level neutral point clamped-active front-end converters(NPC-AFEs)is proposed.With this approach,the prediction model of three-level NPC-AFEs is established inα-βreference frame,and the control objective of low average switching frequency is introduced into a cost function.The proposed method not only achieves the desired control performance under low switching frequency,but also performs the efficient operation for the three-level NPC-AFEs.The simulation results are provided to verify the effectiveness of proposed control scheme. 展开更多
关键词 finite control set-model predictive control(FCS-MPC) three-level neutral point clamped active front-end converters(NPC-AFEs) switching frequency
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High Frequency Transformers for DC/DC Converter Used in Solar PV System
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作者 J. Lu D. Butler 《Journal of Energy and Power Engineering》 2011年第6期536-541,共6页
This paper presents and investigates planar and coaxial high frequency power transformers used for DC/DC converters in a three phase photo voltaic (PV) power systems. The winding structure including a Faraday shield... This paper presents and investigates planar and coaxial high frequency power transformers used for DC/DC converters in a three phase photo voltaic (PV) power systems. The winding structure including a Faraday shield between the primary and secondary windings is designed to minimize eddy current losses, skin and proximity effects, and to reduce the leakage inductance, and the inter winding coupling capacitance. Finite Element Method is employed to analyze the magnetic flux and eddy current distributions. The two different kinds of prototype high frequency transformers are designed and tested. The simulation and experiment results are demonstrated and compared with non-shielded transformers. The shielded transformers have achieved the expected results with a relatively small coupling capacitance, compared with the conventional high frequency transformer. This shield decreases the inter-winding coupling capacitance Cps. The topology of this shield has to be such that it acts as a Faraday screen while avoiding eddy current generation. 展开更多
关键词 DC/DC converter high frequency transformer solar PV system shielding effect magnetic field eddy current.
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A Novel Device for Real-Time Monitoring of High Frequency Phenomena in CENELEC PLC Band
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作者 Bashir Ahmed Siddiqui Pertti Pakonen Pekka Verho 《Smart Grid and Renewable Energy》 2012年第2期152-157,共6页
This paper proposes the design and development of a novel, portable and low-cost intelligent electronic device (IED) for real-time monitoring of high frequency phenomena in CENELEC PLC band. A high speed floating-poin... This paper proposes the design and development of a novel, portable and low-cost intelligent electronic device (IED) for real-time monitoring of high frequency phenomena in CENELEC PLC band. A high speed floating-point digital signal processor (DSP) along with 4 MSPS analog-to-digital converter (ADC) is used to develop the intelligent electronic device. An optimized algorithm to process the analog signal in real-time and to extract the meaningful result using signal processing techniques has been implemented on the device. A laboratory environment has setup with all the necessary equipment including the development of the load model to evaluate the performance of the IED. Smart meter and concentrator is also connected to the low voltage (LV) network to monitor the PLC communication using the IED. The device has been tested in the laboratory and it has produced very promising results for time domain as well as frequency domain analysis. Those results imply that the IED is fully capable of monitoring high frequency disturbances in CENELEC PLC band. 展开更多
关键词 Power Line Communication (plc) DIGITAL Signal PROCESSOR (DSP) Analog-to-Digital converter (ADC) Fast FOURIER Transform (FFT) High frequency (HF) Interference
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Research on variable frequency and speed regulation of motor system based on PLC
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作者 Min ZHENG 《International Journal of Technology Management》 2015年第2期41-43,共3页
This paper presents the composition, control scheme and signal processing method of frequency conversion motor speed testing system based on $7-200 PLC, and design the hardware circuit, the trapezoidal chart procedure... This paper presents the composition, control scheme and signal processing method of frequency conversion motor speed testing system based on $7-200 PLC, and design the hardware circuit, the trapezoidal chart procedure and touch screen display program. The debugging test shows that the system is simple, practical, and related design work has laid the foundation for the future. 展开更多
关键词 INVERTER frequency control touch screen $7-200 plc PID
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A Current-Mode DC-DC Buck Converter with High Stability and Fast Dynamic Response 被引量:2
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作者 陈东坡 何乐年 严晓浪 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第10期1742-1749,共8页
A current-mode DC-DC buck converter with high stability is presented. The loop gain's expression of the current-mode converter is derived by employing an advanced model of a current-mode control converter. After anal... A current-mode DC-DC buck converter with high stability is presented. The loop gain's expression of the current-mode converter is derived by employing an advanced model of a current-mode control converter. After analyzing the loop gain's expression, which illustrates the method of selecting suitable frequency compensation for the control loop,a novel pole-zero tracking frequency compensation is proposed. Based on theoretical analysis, a DC-DC buck converter with high stability is designed with 0.5μm-CMOS technology. The simulated results reveal that the stability of the converter is independent of the load current and the input voltage. Moreover,the converter provides a full load transient response setting time of less than 5μs and overshoots and undershoots of less than 30mV. 展开更多
关键词 DC-DC converter CURRENT-MODE frequency compensation power management
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基于PLC和调速装置的纸机能耗控制系统设计
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作者 田宇 张华 任芸芸 《造纸科学与技术》 2024年第5期99-102,共4页
为提高造纸机真空部的自动化控制水平,提升造纸企业的成本控制能力,基于PLC和真空度传感器等硬件对变频器功率实施控制,进而实现对水泵和真空泵的动态调整,使水流量和变频器功率维持在较低水平,降低造纸机干燥部运行能耗。为实现该系统... 为提高造纸机真空部的自动化控制水平,提升造纸企业的成本控制能力,基于PLC和真空度传感器等硬件对变频器功率实施控制,进而实现对水泵和真空泵的动态调整,使水流量和变频器功率维持在较低水平,降低造纸机干燥部运行能耗。为实现该系统的工业应用,提出了纸机能耗控制系统的主程序流程,同时采用WinCC(Windows Control Center,视窗控制中心)组态软件为上位机设计人机交互界面。该操作界面简洁美观、交互友好,可帮助车间工作人员实时掌握纸机真空部运行数据,合理调整真空部变频器运行功率,实现低能耗生产。 展开更多
关键词 plc 真空度传感器 变频器 软硬件设计
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基于PLC与变频器的恒压供水系统设计 被引量:1
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作者 王彦勇 《机械工程与自动化》 2024年第2期124-126,129,共4页
采用PLC和变频器相结合设计恒压供水系统,采集管网的水压力,经A/D转换后送入PLC,经PLC的PID运算后输出信号来控制变频器的输出电压和频率,改变电动机的转速来改变供水量,最终使管网水压力值稳定在恒定值。实践证明,该系统稳定可靠,同时... 采用PLC和变频器相结合设计恒压供水系统,采集管网的水压力,经A/D转换后送入PLC,经PLC的PID运算后输出信号来控制变频器的输出电压和频率,改变电动机的转速来改变供水量,最终使管网水压力值稳定在恒定值。实践证明,该系统稳定可靠,同时还具有良好的节能效果。 展开更多
关键词 plc PID 变频器 恒压供水系统
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PLC与变频器在真空抽气系统中的应用
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作者 张安洁 张宝夫 《机械管理开发》 2024年第5期318-320,323,共4页
分析了真空抽气系统的运行特性,根据罗茨泵抽气系统的入口压力与电机转速的关系,设计了一个PLC与变频器在真空抽气系统的应用项目。该项目采用PLC的模拟量输入采集压力传感器的信号,模拟量输出控制变频器的输入电流,从而调节电机的转速... 分析了真空抽气系统的运行特性,根据罗茨泵抽气系统的入口压力与电机转速的关系,设计了一个PLC与变频器在真空抽气系统的应用项目。该项目采用PLC的模拟量输入采集压力传感器的信号,模拟量输出控制变频器的输入电流,从而调节电机的转速,通过项目的硬件组态、参数设置、PLC程序设计与调试,实现了项目的控制功能。 展开更多
关键词 罗茨泵 真空抽气系统 变频器 plc
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基于PLC的医用电梯控制系统的设计
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作者 范建锋 《自动化应用》 2024年第3期92-94,共3页
与传统电梯控制系统相比,医用电梯控制系统需更注重电梯升降过程的平稳性,以保证患者的舒适度,因此,需设计医用电梯控制系统。首先,采用西门子S7-1200系列PLC作为主控制单元,采用ACS880变频器驱动曳引电机与门电机。然后,通过梯形图的... 与传统电梯控制系统相比,医用电梯控制系统需更注重电梯升降过程的平稳性,以保证患者的舒适度,因此,需设计医用电梯控制系统。首先,采用西门子S7-1200系列PLC作为主控制单元,采用ACS880变频器驱动曳引电机与门电机。然后,通过梯形图的编译实现呼叫应答、平层开关检测、目标楼层的运行和停止等功能。最后,增加电梯运行安全保护功能,一旦出现危险情况可立即报警。经测试,该系统稳定可靠、调速平滑、安全性高,可应用于各种医用环境。 展开更多
关键词 医用电梯 变频器 plc控制
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基于PLC的变频造纸机双闭环调速控制方法
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作者 李秋 魏晓艳 袁观娜 《造纸科学与技术》 2024年第8期46-50,共5页
为了提高变频造纸机的控制精度与稳定性,提出基于PLC的变频造纸机双闭环调速控制方法。首先,对变频造纸机的电机展开建模分析,为后续调速控制提供依据;其次,采用PLC技术设计变频造纸机控制系统,计算造纸机理想转速比,结合实际转速获得... 为了提高变频造纸机的控制精度与稳定性,提出基于PLC的变频造纸机双闭环调速控制方法。首先,对变频造纸机的电机展开建模分析,为后续调速控制提供依据;其次,采用PLC技术设计变频造纸机控制系统,计算造纸机理想转速比,结合实际转速获得控制偏差,采用PI控制方式完成电流调节环节与转速调节环节的控制;最后,引入灰狼算法在变频造纸机双闭环调速控制目标函数的基础上优化PI控制参数,以此实现变频造纸机双闭环调速的优化控制。实验结果表明,在干扰环境中所提方法可高效、稳定地实现控制。 展开更多
关键词 建模分析 plc技术 变频造纸机 双闭环调速控制 灰狼算法
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A high performance adaptive on-time controlled valley-current-mode DC–DC buck converter 被引量:3
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作者 Chanrong Jiang Changchun Chai +1 位作者 Chenxi Han Yintang Yang 《Journal of Semiconductors》 EI CAS CSCD 2020年第6期48-55,共8页
This paper presents an AOT-controlled(adaptive-on-time,AOT)valley-current-mode buck converter for portable application.The buck converter with synchronous rectifier not only uses valley-current-mode control but also p... This paper presents an AOT-controlled(adaptive-on-time,AOT)valley-current-mode buck converter for portable application.The buck converter with synchronous rectifier not only uses valley-current-mode control but also possesses hybridmode control functions at the same time.Due to the presence of the zero-current detection circuit,the converter can switch freely between the two operating modes without the need for an external mode selection circuit,which further reduces the design difficulty and chip area.The converter for the application of high power efficiency and wide current range is used to generate the voltage of 0.6–3.0 V with a battery source of 3.3–5.0 V,while the load current range is 0.05–2 A.The circuit can work in continuous conduction mode with constant frequency in high load current range.In addition,a stable output voltage can be obtained with small voltage ripple.In pace with the load current decreases to a critical value,the converter transforms into the discontinuous conduction mode smoothly.As the switching period increases,the switching loss decreases,which can significantly improve the conversion efficiency.The proposed AOT controlled valley current mode buck converter is integrated with standard 0.18μm process and the simulation results show that the converter provides well-loaded regulations with power efficiency over 95%.When the circuit switches between the two conduction modes drastically,the response time can be controlled within 30μs.The undershoot voltage is controlled within 25 mV under a large current hopping range. 展开更多
关键词 adaptive on-time buck converter fast response constant frequency high efficiency
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Two-stage Voltage Closed Loop Control Scheme for Hybrid Excited Synchronous Generator-matrix Converter Generation System 被引量:1
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作者 SHI Mingming ZHOU Bo WEI Jiadan MAO Yiran 《中国电机工程学报》 EI CSCD 北大核心 2012年第3期I0001-I0023,共23页
关键词 同步发电机 矩阵变换器 转换器 控制方案 发电系统 混合励磁 电力电子系统集成 闭环
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Tunable circularly-polarized turnstile-junction mode converter for high-power microwave applications
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作者 Xiao-Yu Wang Yu-Wei Fan +2 位作者 Ting Shu Cheng-Wei Yuan Qiang Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第6期502-506,共5页
Frequency tunability has become a subject of concern in the field of high-power microwave(HPM) source research.However, little information about the corresponding mode converter is available. A tunable circularly-po... Frequency tunability has become a subject of concern in the field of high-power microwave(HPM) source research.However, little information about the corresponding mode converter is available. A tunable circularly-polarized turnstilejunction mode converter(TCTMC) for high-power microwave applications is presented in this paper. The input coaxial TEM mode is transformed into TE(10) mode with different phase delays in four rectangular waveguides and then converted into a circularly-polarized TE(11) circular waveguide mode. Besides, the rods are added to reduce or even eliminate the reflection. The innovations in this study are as follows. The tunning mechanism is added to the mode converter, which can change the effective length of rectangular waveguide and the distance between the rods installed upstream and the closest edge of the rectangular waveguide, thus improving the conversion efficiency and bandwidth. The conversion efficiency of TCTMC can reach above 98% over the frequency range of 1.42 GHz–2.29 GHz, and the frequency tunning bandwidth is about 47%. Significantly, TCTMC can obtain continuous high conversion efficiency of different frequency points with the change of tuning mechanism. 展开更多
关键词 mode converter high conversion efficiency frequency tuning performance
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