共查询到20条相似文献,搜索用时 31 毫秒
1.
A new ZVT-PWM DC-DC converter 总被引:7,自引:0,他引:7
In this paper, a new active snubber cell that overcomes most of the drawbacks of the normal "zero voltage transition-pulse width modulation" (ZVT-PWM) converter is proposed to contrive a new family of ZVT-PWM converters. A converter with the proposed snubber cell can also operate at light load conditions. All of the semiconductor devices in this converter are turned on and off under exact or near zero voltage switching (ZVS) and/or zero current switching (ZCS). No additional voltage and current stresses on the main switch and main diode occur. Also, the auxiliary switch and auxiliary diodes are subjected to voltage and current values at allowable levels. Moreover, the converter has a simple structure, low cost, and ease of control. A ZVT-PWM boost converter equipped with the proposed snubber cell is analyzed in detail. The predicted operation principles and theoretical analysis of the presented converter are verified with a prototype of a 2 kW and 50 kHz PWM boost converter with insulated gate bipolar transistor (IGBT). In this study, a design procedure of the proposed active snubber cell is also presented. Additionally, at full output power in the proposed soft switching converter, the main switch loss is about 27% and the total circuit loss is about 36% of that in its counterpart hard switching converter, and so the overall efficiency, which is about 91% in the hard switching case, increases to about 97% 相似文献
2.
A new ZVT-ZCT-PWM DC-DC converter 总被引:4,自引:0,他引:4
In this paper, a new active snubber cell is proposed to contrive a new family of pulse width modulated (PWM) converters. This snubber cell provides zero voltage transition (ZVT) turn on and zero current transition (ZCT) turn off together for the main switch of a converter. Also, the snubber cell is implemented by using only one quasi resonant circuit without an important increase in the cost and complexity of the converter. New ZVT-ZCT-PWM converter equipped with the proposed snubber cell provides most the desirable features of both ZVT and ZCT converters presented previously, and overcomes most the drawbacks of these converters. Subsequently, the new converter can operate with soft switching successfully at very wide line and load ranges and at considerably high frequencies. Moreover, all semiconductor devices operate under soft switching, the main devices do not have any additional voltage and current stresses, and the stresses on the auxiliary devices are at low levels. Also, the new converter has a simple structure, low cost and ease of control. In this study, a detailed steady state analysis of the new converter is presented, and this theoretical analysis is verified exactly by a prototype of a 1-kW and 100-kHz boost converter. 相似文献
3.
Xiangning He Chen A. Hongyang Wu Yan Deng Rongxiang Zhao 《Industrial Electronics, IEEE Transactions on》2006,53(3):727-735
A passive lossless snubber circuit for multilevel inverters is proposed in this paper. The topology is simple and requires no extra control circuit. In order to reduce the high-voltage stress on power switches with this snubber circuit, an improved snubber circuit is presented by adding separate low-power direct current voltage sources into the original one. The operating principles and design considerations are described in detail in this paper. A prototype of a three-phase three-level diode-clamped inverter with the improved passive lossless snubber is built and tested. The simulation and experimental results indicate that not only can it realize the soft switching operation of the three-level inverter with low-voltage stress but also the topology and the control are simple. 相似文献
4.
This paper describes a soft switching active snubber for an IGBT operating in a single switch unity power factor three-phase diode rectifier. The soft switching snubber circuit provides zero-voltage turn-off for the main switch. The high turn-off losses of the IGBT due to current tailing are reduced by zero-voltage switching. This allows the circuit to be operated at very high switching frequencies with regulated DC output voltage, high quality input current and unity input power factor. Simulation and experimental results are included 相似文献
5.
The pulsewidth-modulated (PWM) current-source inverter (CSI) used in AC motor drive applications can be implemented with symmetric gate turn-off thyristors (GTOs). One of the major difficulties in the optimization of the GTO switch and the snubber components of the inverter is the variation in different switching conditions encountered during normal operation. Past work has concentrated on the GTO and snubber components in voltage-source applications, where commutation of the GTO device is an independent process and does not affect the operation of the other inverter devices. This paper proposes the characterization of the GTO and the snubber components by formulation of the CSI equivalent circuit during the device commutation period. From the equivalent circuit, the state equations are derived, thereby obtaining accurate voltage and current waveforms of the GTO and associated snubbers. From the analysis, the component power loss can be calculated and optimization performed. Simulation results are verified by using both a laboratory prototype and medium-voltage drive system 相似文献
6.
High-power-factor soft-switched boost converter 总被引:2,自引:0,他引:2
Yungtaek Jang Jovanovic M.M. Kung-Hui Fang Yu-Ming Chang 《Power Electronics, IEEE Transactions on》2006,21(1):98-104
A novel implementation of the high-power-factor (HPF) boost converter with active snubber is described. The snubber circuit reduces the reverse-recovery-related losses of the rectifier and also provides zero-voltage switching for the boost switch and zero-current switching for the auxiliary switch. The performance of the proposed approach was evaluated on an 80-kHz, 1.5-kW, universal-line range, HPF boost converter. The proposed technique improves the efficiency by approximately 2% at full load and low line. 相似文献
7.
A simple snubber configuration for three-level GTO inverters 总被引:1,自引:0,他引:1
Jeong-Hyoun Sung Kwanghee Nam 《Power Electronics, IEEE Transactions on》1999,14(2):246-257
A simple snubber configuration for three-level gate turn-off thyristor (GTO) inverters is proposed. The proposed snubber has a single resistor per arm for stored energy dissipation, while the conventional RLD/RCD snubber contains six. This implies that the proposed snubber needs only one chopper circuit per arm for snubber energy recovery. This helps reduce the size, cost, and number of components. Besides the single resistor, the proposed snubber requires two less diodes per arm than the RLD/RCD snubber. Furthermore, the proposed snubber resolves the voltage imbalance problem between inner and outer GTOs without additional components. We have analyzed the proposed circuits and proven its performance through simulations and experiments 相似文献
8.
《Power Electronics, IEEE Transactions on》2009,24(8):1977-1991
9.
In-Dong Kim Eui-Cheol Nho Heung-Geun Kim Jong Sun Ko 《Industrial Electronics, IEEE Transactions on》2004,51(6):1290-1296
This paper proposes a snubber circuit for a flying capacitor multilevel inverter and converter. It also explains the concept of constructing a snubber circuit for a multilevel inverter and converter. The proposed snubber circuit makes use of an Undeland snubber as a basic snubber unit, and thus can be regarded as a generalized Undeland snubber for a flying capacitor multilevel inverter and converter. It has such an advantage of Undeland snubber used in the two-level inverter. Compared with a conventional RLD/RCD snubber for multilevel inverter and converter, the proposed snubber keeps such good features as fewer number of components, reduction of voltage stress of main switching devices due to low overvoltage, and improved efficiency of system due to low snubber loss. In this paper, the proposed snubber is applied to a three-level flying capacitor inverter, and its features are in detail demonstrated by computer simulation and experimental result. 相似文献
10.
Finney S.J. Tooth D.J. Flethcer J.E. Williams B.W. 《Power Electronics, IEEE Transactions on》1999,14(6):1101-1110
The turn-on loss of high-speed insulated gate bipolar transistors (IGBTs) accounts for a significant proportion of the total switching energy. In many applications, this loss is increased by the energy associated with diode reverse recovery of current. Such energy is absorbed by the IGBT switch at high voltage. Linear turn-on snubber inductors may be used to control the turn-on loss, diode reverse recovery, and electromagnetic compatibility (EMC). These snubbers have the disadvantage of involving substantial stored energy that must be reset, normally by dissipation. An alternative is to use a saturable turn-on snubber inductor, which stores substantially less energy than a linear inductor. In this paper, the suitability of saturable turn-on snubber inductors for use with IGBTs is investigated, and possible circuit topologies for single-ended and bridge-leg applications are proposed. Mathematical analysis, simulation, and practical results are presented for the saturable inductor turn-on snubber circuit topologies 相似文献
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12.
Bong-Hwan Kwon Gang-Youl Jeong Sung-Hoon Han Duk-Ho Lee 《Industrial Electronics, IEEE Transactions on》2002,49(5):1110-1119
In this paper, a novel pulsewidth-modulated line conditioner with fast output voltage control is proposed. The line conditioner is made up of an AC chopper with reversible voltage control and a transformer for series voltage compensation. In the AC chopper, a proper switching operation is achieved without the commutation problem. To absorb energy stored in line stray inductance, a regenerative DC snubber can be utilized which has only one capacitor without discharging resistors or complicated regenerative circuit for snubber energy. Therefore, the proposed AC chopper gives high efficiency and reliability. The output voltage of the line conditioner is controlled using a fast sensing technique of the output voltage. It is also shown via some experimental results that the presented line conditioner gives good dynamic and steady-state performance for high quality of the output voltage. 相似文献
13.
Xiangning He Finney S.J. Williams B.W. Zhao-Ming Qian 《Power Electronics, IEEE Transactions on》1997,12(1):173-179
A novel passive lossless turn-on snubber with a soft-clamped turn-off snubber circuit for voltage source inverters is proposed. The energy trapped in the snubber is recovered into the DC supply and load without any active devices, associated control circuitry, or resistors. The overshoot voltage on the switches is clamped, and the peak switch current is low, making this snubber suitable for use in high-power insulated gate bipolar transistor (IGBT) inverters 相似文献
14.
Sang-Kyoo Han Hyun-Ki Yoon Gun-Woo Moon Myung-Joong Youn Yoon-Ho Kim Kang-Hee Lee 《Power Electronics, IEEE Transactions on》2005,20(6):1271-1279
A new active clamping zero-voltage switching (ZVS) pulse-width modulation (PWM) current-fed half-bridge converter (CFHB) is proposed in this paper. Its active clamping snubber (ACS) can not only absorb the voltage surge across the turned-off switch, but also achieve the ZVS of all power switches. Moreover, it can be applied to all current-fed power conversion topologies and its operation as well as structure is very simple. Since auxiliary switches in the snubber circuit are switched in a complementary way to main switches, an additional PWM IC is not necessary. In addition, it does not need any clamp winding and auxiliary circuit besides additional two power switches and one capacitor while the conventional current-fed half bridge converter has to be equipped with two clamp windings, two ZVS circuits, and two snubbers. Therefore, it can ensure the higher operating frequency, smaller-sized reactive components, lower cost of production, easier implementation, and higher efficiency. The operational principle, theoretical analysis, and design considerations are presented. To confirm the operation, validity, and features of the proposed circuit, experimental results from a 200-W, 24-200Vdc prototype are presented. 相似文献
15.
Soft Switching Circuit for Interleaved Boost Converters 总被引:1,自引:0,他引:1
A zero-voltage switching-zero-current switching interleaved boost converter is proposed in this paper. An active circuit branch in parallel with the main switches is added and it is composed of an auxiliary switch and a snubber capacitor. By using this interleaved converter topology, zero current turn-on and zero voltage turn-off of the main switches can be achieved and the reverse-recovery loss of boost diode can be reduced. In addition, the auxiliary switches are zero-voltage transmission during the whole switching transition. A prototype of boost converter rated at 1.2kW has been built to confirm the effectiveness of the converter 相似文献
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17.
为提高转换效率并降低电源开关的电流应力,提出一种基于新型有源缓冲电路的PWM DC-DC升压变换器。该有源缓冲电路使用ZVT—ZCT软开关技术,分别提供了总开关ZVT开启及ZCT闭合、辅助开关ZCS开启及ZCT闭合。消除了总开关额外的电流及电压应力,消除了辅助开关电压应力,且有源缓冲电路的耦合电感降低了电流应力。另外,通过连续将二极管添加到辅助开关电路,防止来自共振电路的输入电流应力进入总开关。实验结果表明,相比传统的PWM变换器,新的DC-DC PWM升压变换器在满负荷时电流应力降低且总体效率能达到98.7%。 相似文献
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In this article, the new ZVT–ZCT Quasi-Resonant DC Link, which ensures zero crossings at any time required for soft switching (SS) and provides zero voltage transition (ZVT) turn-on and zero current transition (ZCT) turn-off together for the main switch of active snubber cell in pulse width modulated or space vector modulated operation of inverter is presented. The new circuit combines the most desirable features of the circuits presented previously and overcomes most drawbacks of these circuits by using only one auxiliary switch with fewer other components. Consequently, new ZVT–ZCT Quasi-Resonant DC Link, which is verified by a prototype of a 1.2 kW and 50 kHz circuit, is analysed in detail. All semiconductor devices operate under SS, the main switch is subjected to no additional voltage and current stresses, and the stress on the auxiliary switch is very low in the proposed new inverter. 相似文献
20.
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