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1.
为了克服传统AC-AC变换器的不足,提出一种新型的电压型准阻抗源AC-AC变换电路。研究了电路基本结构、工作原理,采用脉冲宽度调制(PWM)法对电路进行总体控制改变输出电压,给出了Matlab/Simulink下系统电路的仿真结果,最后在仿真的基础上利用TMS320F2812搭建了实验电路。实验结果验证了电路结构的可靠性和可行性。  相似文献   

2.
摘要:为了克服传统三相斩控式交流调压器的不足,提出了一种三相电压型准阻抗源变换器电路拓扑。研究了其拓扑结构和工作原理,推导了输出电压与占空比的定量关系。运用matlab对电路进行了仿真,并根据仿真结果建立了实验电路,采用脉冲宽度调制法(PWM)对电路进行总体控制,得到占空比为0.2与0.8时的三相电压波形。实验结果验证了三相电压型准阻抗源电压调节的的可靠性和可行性。  相似文献   

3.
This paper shows that by transforming both sides of the matrix converter to the d-q-o frames of their respective frequencies, there is significant simplification in the transformation matrix which enables the network of one side to be integrated to the other. Thus, it is possible to design for operation with field vector control on the motor side and unity displacement factor on the supply side. Laboratory experimental and digital simulation results are presented to substantiate the theory. The matrix converter used in the test is based on three modules of voltage-source SPWM converters to implement the nine switches and it has the innovative feature that the SVC voltages (for displacement factor improvement) can be derived from the zero-sequence voltages  相似文献   

4.
This paper presents an integrated high voltage digital-to-analog converter, which is fabricated in a 0.35 \({\upmu }\) m high voltage CMOS technology (AMS H35), and can be applied in high voltage applications up to 115 V. The high voltage output is controlled by 8-bit digital input code. In order to improve the accuracy and decrease the required area, it is implemented by a low voltage DAC and a high voltage amplifier for boosting the controllable output voltage. Since the current consumption from the high voltage power supply is only 80 \({\upmu }\) A, it can be powered by a charge pump which generates 115 V from a battery with 3.7 V DC. Combining with a 8*8 external high voltage switch array, the proposed high voltage digital-to-analog converter can drive up to 64 individual channels of antenna array with a voltage from 0 to 115 V. It will greatly reduce the complexity and cost of mobile applications which use tunable microwave devices and require high voltages. The feasibility is proved by post-simulation result and experimental test result. The proposed concept of the high voltage ASIC is also proved by a demonstrator.  相似文献   

5.
A circuit configuration and circuit topological family of voltage mode ac-ac converters with high frequency ac links, which are based on forward converters, and a uni-polarity phase-shifted control strategy are proposed and deeply investigated. These kinds of converters consist of a input cycloconverter, a high frequency transformer, an output cycloconverter, input and output filters, and can transfer an unsteady ac voltage with a high harmonic into steady same-frequency ac sinusoidal voltage with a low harmonic. By using uni-polarity phase-shifted control strategy, output filtering inductance current is naturally commutated, and zero voltage switching of the output cycloconverter is realized. The converters' averaging model, the output characteristic curve, and design criteria for the key circuit parameters are given. The theoretical analysis and test result of 1kVA 220V /spl plusmn/ 10% 50Hzac/110V 50Hz ac prototype have shown that the converters have such advantages as high frequency electrical isolation, simple topology, two-stage power conversion (LFAC/HFAC/LFAC), bidirectional power flow, uni-polarity synchronized pulsewidth modulation waveform, high efficiency, high power density, high steady precision, low total harmonic distortion of the output voltage, strong adaptability to various loads, high line power factor, and low audio noise etc.  相似文献   

6.
《今日电子》2001,(1):15-15
输出功率范围从5W至250W,高度设计灵活性,待机功耗低,最大限度降低了系统成本  相似文献   

7.
A fault-tolerant ac-ac converter capable of supplying a three-phase induction machine from the grid with an unitary power factor has been proposed. With one faulted converter leg, two of the remaining five legs are connected to the grid, two legs are connected to the machine, and a common leg is shared by the grid and the machine. The previously developed control strategy required a too great computation time for practical implementation. In this paper, a new control strategy is suggested for this power converter. It enables an easier control implementation. Experimental results are provided.  相似文献   

8.
A new high voltage class AB bipolar voltage-current converter (VCCS), which features low offset voltage and is suitable for monolithic IC fabrication, is described. The architecture of the converter is particularly suited for the implementation of a precision VCCS with wide input and output voltage range. Some SPICE simulations and experimental results are also reported, which demonstrate the effectiveness of the proposed configuration  相似文献   

9.
A high-sensitivity voltage-to-frequency converter (VFC) using an all-MOS voltage window comparator is presented in this work. The circuit is composed of one voltage-to-current converter, one charge and discharge circuit, and one all-MOS voltage window comparator. The input voltage is converted into a current which in turn triggers the charge and discharge circuit, where a built-in capacitor is driven. The voltage window comparator monitors the variated voltage on the capacitor and generate an oscillated output of which the vibration frequency is linearly dependent to the input voltage. In this way, the worst-case linear range of the output frequency of the proposed VFC is 0-55.40 MHz verified by simulations given a 0-0.9 V input range. The physical measurement of the proposed VFC shows a 0-52.95 MHz output frequency given a 0-0.9 V input range. The error in linearity is better than 8.5% while the power dissipation is merely 0.218 mW.  相似文献   

10.
This paper presents a four-terminal, physically based, high-voltage diffused resistor model. The model accounts for depletion, inversion, and accumulation at the surface due to the MOS effect of metal field plates, as well as the depletion pinching effect at the sides and bottom of the diffused resistor  相似文献   

11.
DC voltage control strategy for a five-level converter   总被引:8,自引:0,他引:8  
This paper describes a control method for a three-phase five-level diode-clamp pulse width modulation (PWM) converter considering DC-link capacitor voltage balancing problem. The proposed control circuit uses multiband hysteresis comparators (MHCs) to simplify the control of the main circuit. The DC-link capacitor voltage balancing problem is solved by changing the shape of the MHC. The proposed method can (1) overcome voltage imbalance at the DC-link capacitors; (2) achieve a unity power factor; (3) generate nearly sinusoidal input currents; and (4) regenerate electric power back to the power system. Simulation and experimental results demonstrate the validity of the proposed method  相似文献   

12.
A high efficiency interleaved active clamp forward converter with self-driven synchronous rectifiers for a modular power processor is presented. To simplify the gate drive circuits, the n–p MOSFETs coupled active clamp method is used. An efficiency of about 90% for a load range of 50-100% is achieved. Details of design for the power stage and current mode control circuit are provided, and also some experimental results are given.  相似文献   

13.
赵冀川 《电子测试》2016,(23):44-45
介绍了高压直流输电换流阀饱和电抗器基本原理、构成及特点;分析了饱和电抗器的作用功能;对于电抗器的特性进行了详细的论述和研究,最后给出了基于某直流输电工程实际运行情况的高压直流换流阀饱和电抗器的铁损仿真实验.  相似文献   

14.
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   

15.
An automated system for the intercomparison of thermal voltage converters at the National Bureau of Standards--Gaithersburg is described. It employes a two-channel comparator with components interfaced using the IEEE-488 bus standard. The design and performance of this system are presented and several advantages and disadvantages of this and other automated comparator systems are discussed.  相似文献   

16.
目前,无线和有线通信系统的设计者们迫切需要低噪声、高速度、多载波、高带宽的器件以及更快速的系统开发手段。图1中所给出的高速转换器在测量信号通路中具有功放频应预矫功能,在接收信号通路中具有基带(I/Q)信号检测功能,在传输信号通路中具有信号调制功能。  相似文献   

17.
A novel implementation of a rail-to-rail exponential voltage to voltage converter is presented. It is based on a pseudo-exponential approximation that is easily achieved by the nonlinear currents of a class-AB transconductor. Measurement results for a 0.5 /spl mu/m CMOS technology show a 52 dB output voltage range with linearity error less than /spl plusmn/2 dB using a dual supply voltage of /spl plusmn/750 mV. The power dissipation is less than 40 /spl mu/W.  相似文献   

18.
The operation of a voltage source converter (VSC) with regeneration capability, controllable power factor, and low distortion of utility currents is analyzed at increased utility voltage. Increase in the utility voltage causes a VSC to saturate and enter a nonlinear mode of operation. To operate under elevated utility, two steps are taken: (1) a pulse width modulation (PWM) algorithm is implemented which extends the linear region of operation by 15%, and (2) a PWM saturation regulator is used to control the reactive current at higher utility voltages. The PWM algorithm reduces the switching losses by at least 33% and the effect of blanking time by one-third. All analytical results are experimentally verified on a 100 kW three-phase VSC  相似文献   

19.
《Electronics letters》2008,44(17):1029-1030
A novel zero voltage switching (ZVS) isolated converter is presented. The output voltage doubler is used on the output side to achieve the boost type of voltage conversion ratio. Active-clamping technique is adopted to realise the ZVS turn-on of all switches. The proposed circuit has no large output inductor such that the adopted circuit has a simpler structure, lower cost and no effective duty loss. Finally experimental results based on a 300 W prototype are provided to verify the effectiveness of the proposed converter.  相似文献   

20.
论述了 SIPOS钝化的原理、生产 SIPOS晶体管的工艺步骤 ,以及在制造过程中易出现的问题和解决方法  相似文献   

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