共查询到20条相似文献,搜索用时 0 毫秒
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This paper describes the design of an AC–AC converter capable of generating a high-quality output. It is based on the Cuk configuration, with the transistors replaced by bidirectional switches. Since there are no transformers in the configuration, the converter lends itself to a compact and lightweight implementation. The design process is aimed at using, as much as possible, the tools and devices already developed for DC–DC applications. This approach greatly simplifies the design and implementation of the converter. An integrated circuit, developed for DC–DC applications, is used to control the converter. Both the set-point and the feedback signal are rectified in order to fit the input range of the controller. Tests performed show that the output exhibits a maximum total harmonic distortion of 3% (resistive load). The efficiency is slightly higher than 89%, and the average output regulation is 0.3%. The converter is capable of correcting voltage sags down to 60% and voltage swells up to 30%, with the output returning to its nominal value within one mains cycle. The results show that the converter is suitable for energizing information-processing equipment. 相似文献
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Do-Hyun Jang Gyu-Ha Choe 《Industrial Electronics, IEEE Transactions on》1998,45(6):905-911
A step-up/down AC voltage regulator is proposed, in which a tap-changing transformer and a pulsewidth modulation (PWM) AC chopper are combined. The proposed regulator can step up or down the output voltage to input voltage. Also, the proposed regulator restrains more harmonics of output voltage compared to the conventional PWM regulator. The input current flows continuously in the proposed regulator, while it flows discontinuously in the conventional PWM regulator. Through digital simulation, several characteristics are investigated theoretically and then compared with those of conventional schemes. Practical verification of the theoretical predictions is presented to confirm the capabilities of the proposed regulator 相似文献
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《Solid-State Circuits, IEEE Journal of》1969,4(4):192-195
This versatile and highly efficient voltage regulator, for applications where the conventional series regulator and the inductor type of switching regulator are impractical, uses solid-state switching techniques. Efficiencies greater than 90 percent have been achieved, independent of input voltage amplitudes. Good load regulation is provided, with a ripple increase as the main effect of a load-current increase. High-peak-current capability is another major advantage of the regulator. The circuit described successfully delivers power peaks of 600 watts. Output voltage restoration from the power line is accomplished as quickly as possible. Some applications of the regulator are prereugulation, class-B audio amplifiers, and solenoid driving. 相似文献
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《Solid-State Circuits, IEEE Journal of》1968,3(4):380-387
A complete series voltage regulator circuit capable of delivering /SUP 1///SUB 2/ ampere of current has been built on a single 63/spl times/66-mil die using the conventional all- diffused processing technology. Improved performance has been achieved by using an internal low-power voltage regulator to supply the desired dc output voltage reference directly to a second main regulator. This permits the dc and ac characteristics of the regulator to be separately optimized with the result that excellent transient characteristics are realized simultaneously with low drift and excellent regulation. 相似文献
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Man Siu Mok P.K.T. Ka Nang Leung Lam Y.-H. Wing-Hung Ki 《Circuits and Systems II: Express Briefs, IEEE Transactions on》2006,53(4):294-298
The end-point prediction (EPP) scheme for voltage-mode buck regulators is proposed. Internal nodal voltages of the regulator controller are predicted and set automatically by the proposed algorithms and circuits. The settling time of the regulator can therefore be significantly reduced for faster dynamic responses, even with dominant-pole compensation. Proven experimentally by a voltage-mode buck regulator implemented in a 0.35-/spl mu/m CMOS technology, the reference-tracking speed using the EPP scheme is faster than the conventional buck regulator by about six times. 相似文献
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A voltage control strategy for current-regulated PWM inverters 总被引:1,自引:0,他引:1
Wasynczuk O. Sudhoff S.D. Tran T.D. Clayton D.H. Hegner H.J. 《Power Electronics, IEEE Transactions on》1996,11(1):7-15
Alternative voltage control strategies for current-regulated PWM inverters are analyzed, including previously established feedforward and feedforward/feedback controllers and a newly proposed decoupling feedback control strategy. The steady-state and dynamic characteristics of each of these control methods are illustrated and compared for a selected inverter design. It is shown that the feedforward controller exhibits steady-state error and an undesirable overshoot of the output voltages during startup. The addition of a feedback loop eliminates the steady-state error and reduces the overshoot; however, the natural response is underdamped regardless of the choice of feedback gains. A decoupling feedback control strategy that eliminates the disadvantages of the feedforward and feedforward/feedback controllers is described. Using the decoupling feedback controller, it is possible to eliminate the steady-state error and place the closed-loop poles wherever desired. Moreover, if the closed-loop poles are selected appropriately, it is possible to eliminate the overshoot of the output voltages during startup transients 相似文献
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本文介绍了一种利用可控硅相控整流技术调节电压的方法及实用装置。对组成调压装置的主要电路的设计思想和工作原理作了简要分析。并结合该装置的实际应用介绍了一些优点并提出了自己的看法。 相似文献
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Tsu-Hua Ai Jiann-Fuh Chen Tsorng-Juu Liang 《International Journal of Electronics》2013,100(4):485-498
This paper presents a novel switching-mode ac/ac voltage regulator using a bidirectional buck-boost converter. Since it operates at high frequency, the proposed system can be designed compactly, and there is a wide range of input voltage from 1/2 to 2 per unit with fast dynamic response and low harmonics. In order to verify the accuracy of the proposed method, a 500 W prototype has been implemented in the laboratory. From the experimental results, the regulation of the output voltage is within less than 1%. Moreover, the total harmonic distortion (THD) of the input current under full load is 2.46% and the output voltage has a THD of 1.77%. 相似文献
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Shunt active power filters are connected in parallel with the electricity supply network. If the AC mains has a neutral conductor, it is desirable to compensate the mains harmonic currents zero-sequence components. This can be achieved with a four-wire pulsewidth modulation voltage converter connected to the AC mains. In this case, the three-phase and the neutral AC currents must be controlled. A generalization of the space-vector-based current controller in the αβo coordinate system is presented in this paper. With this current controller, all the current harmonic systems of positive, negative, and zero sequence can be injected by the converter and, thus, compensated on the AC mains. The system is also useful to compensate unbalanced currents of fundamental frequency. A useful benefit of this system is that it is possible to control the converter four-wire currents with equal hysteresis errors. Simulation and experimental results are presented 相似文献
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In conventional high frequency 12-V input voltage regulators (VR), large gate driver loss and body diode conduction loss raise crucial challenges to its gate driver implementation. The proposed self-driven topologies are basically buck-derived multiphase interleaving soft switching topologies, which eliminate the synchronous rectifier MOSFET drivers and save driving loss and body diode loss, so that it is a high efficiency, high power density solution for future microprocessors. A 1U four-phase 1.3-V/100-A VRM running at 1MHz demonstrates its advantages (cost, size and efficiency) over the conventional multiphase buck converter. 相似文献
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Han-Woong Park Sung-Jun Park Jin-Gil Park Cheul-U Kim 《Industrial Electronics, IEEE Transactions on》2001,48(3):554-562
Regulation of load voltage in single-phase applications is becoming an important issue for critical loads. This paper presents a novel high-performance single-phase voltage regulator which has a common arm between the rectifier and inverter, and adopts an appropriate switching strategy. The proposed voltage regulator employs six switches and can be implemented by only one three-phase inverter module. The proposed voltage regulator has the capability of delivering sinusoidal input current with unity power factor, good output voltage regulation, and bidirectional power flow. For these purposes, a fully digital controller is designed and implemented using a TMS320F240 digital signal processor. In addition, a novel low-cost AC capacitor is also presented. This type of capacitor requires two DC capacitors and two diodes, enabling low-cost and compact manufacturing. Consequently, the complete voltage regulator system, which is mainly suitable for an uninterruptible power supply as well as reactive or nonlinear loads, can be constructed compactly and inexpensively. Experimental results are presented to verify the feasibility of the proposed voltage regulator system 相似文献
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Belverde G. Galluzzo A. Melito M. Musumeci S. Raciti A. 《Power Electronics, IEEE Transactions on》2001,16(1):132-141
Insulated gate devices, such as metal oxide semiconductor field effect transistors (MOSFETs) or insulated gate bipolar transistors (IGBTs), are increasingly used in high-voltage power converters where a request for fast power switches is growing. Series connection of devices is a viable approach to manage voltages higher than the blocking voltage of the single device. The main problem in such an application is to guarantee the voltage balance across the devices both in steady-state and during switching transients. In this paper, a novel approach is presented, which is used to equalize the voltage sharing during the switching transients. The main advantages of the proposed method consist in avoiding the traditional use of the snubber capacitors, in the output power side, and in working on the gate side. The application of the proposed gate drive technique is firstly discussed and compared with different solutions, hence, validated by experimental tests applied to the control of series connected devices. Finally, a comparison is performed between the transient behaviors of two different configurations: a single switch with high-voltage blocking capability, and in alternative a series of two devices which together ensure the voltage blocking capability of the single switch. The better performances of the latter configuration, working with the proposed control circuit, over the former have been experimentally demonstrated 相似文献
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Experimental evidence is given showing that Ag-n-Si Schottky diodes with resistivity about 40 m?cm have steeper reverse breakdown characteristics than corresponding low-voltage p-n junction regulator diodes fabricated by local epitaxy. Avalanche multiplication in such a diode starts at 1.7 V, and the device has a low positive temperature coefficient of breakdown voltage. 相似文献
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This paper explores the fundamental limitations of the neutral-point voltage balancing problem for different loading conditions of three-level voltage source inverters. A new model in the DQ coordinate frame utilizing current switching functions is developed as a means to investigate theoretical limitations and to offer a more intuitive insight into the problem. The low-frequency ripple of the neutral point caused by certain loading conditions is reported and quantified 相似文献
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Ming Tsung Tsai 《Industrial Electronics, IEEE Transactions on》2004,51(4):933-936
This letter presents an improved control algorithm for the compensation of ac source voltage fluctuation. The proposed idea can be used to regulate both the overvoltage and undervoltage situations with only unidirectional energy transmission. Theoretical analysis has been achieved based on the power flow theory. A case study is demonstrated by means of a prototype experiment to prove its performance and effectiveness. 相似文献
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Jarno Salomaa Mika Pulkkinen Kari Halonen 《Analog Integrated Circuits and Signal Processing》2016,89(2):347-356
This paper presents an SC voltage doubler-based voltage regulator for ultra-low power energy harvesting applications. It produces a stable 1.2-V power supply, using inputs from 0.63 to 1.8 V. External compensation and an on-chip output capacitor ensure good performance even with zero load current and any load capacitance. The regulator tolerates arbitrary input ramp-ups, and is immune to blackout and brownout. A stability analysis for the regulator control loop is presented. The regulator ASIC is implemented in a 180 nm CMOS process. The measured regulator peak power and current efficiency are 63 and 49 %, respectively. The performance has been characterized with load currents from zero to \(100\,\upmu\)A. 相似文献
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An integrated voltage regulator SPICE model is presented. The model takes into account the main electrical characteristics (dropout voltage and quiescent current); the thermal effects of the electrical variables; and one of the electrical effects of the junction temperature, the thermal shutdown, a protection system used by many commercial devices 相似文献