共查询到20条相似文献，搜索用时 191 毫秒
1.
张森善 《北京工业职业技术学院学报》2011,10(2):10-13
三相电压型AC/DC变换器功率控制策略是目前研究的热点。论述了基本三相电压型AC/DC变换器功率控制原理,并进行了仿真研究。对功率控制策略的几个问题进行了探讨,提出了改进建议。 相似文献
2.
This paper presents a novel current feedforward control strategy for a three-phase pulse-width modulation (PWM) DC voltage-type converter based on phase and amplitude control (PAC). With right-angle triangle relation of phasors and principle of conservation of energy, a phasor adjustment method and the relevant low-frequency mathematical model of the system are analyzed in detail, both in rectification and regeneration modes for the converter, are discussed. For improving the traditional PAC dynamic performance, variable load current is detected indirectly by the change of the DC voltage, which is fed to the control system as an additional control variable to generate modulation index and phase angle. Also, the algorithm is derived and the system principle is introduced. Experimental results from a 3 kw laboratory device are included to demonstrate the effectiveness of the proposed control strategy. 相似文献
3.
This paper presents a novel current feedforward control strategy for a three-phase pulse-width modulation (PWM) DC voltage-type converter based on phase and amplitude control (PAC).With right-angle triangle relation of phasors and principle of conservation of energy, a phasor adjustment method and the relevant low-frequency mathematical model of the system are analyzed in detail, both in rectification and regeneration modes for the converter, are discussed.For improving the traditional PAC dynamic performance, variable load current is detected indirectly by the change of the DC voltage, which is fed to the control system as an additional control variable to generate modulation index and phase angle.Also, the algorithm is derived and the system principle is introduced.Experimental results from a 3 kw laboratory device are included to demonstrate the effectiveness of the proposed control strategy. 相似文献
4.
提出一种基于交直交变频器的直流六脉波电压小电容结构和变频控制策略,实时采样母线脉动电压并依据磁链轨迹需求计算空间电压矢量调制脉宽,得到谐波含量较少的逆变输出。在仅考虑电动机感性能量回馈的情况下,根据逆变侧瞬时回馈电流大小及时间计算出直流母线最小电容参数,同时针对瞬时负载波动和转速突变产生的惯性能量回馈问题,用瞬时关断输出方法进行抑制,必要时通过能耗制动单元加以限制。通过Simulink仿真,验证小电容的计算结果和控制方法的可行性。 相似文献
5.
HU Jia-bing HE Yi-kang NIAN Heng 《浙江大学学报(A卷英文版)》2007,8(8):1330-1339
This paper presents a unified positive-and negative-sequence dual-dq dynamic model of wind-turbine driven doubly-fed induction generator(DFIG) under unbalanced grid voltage conditions. Strategies for enhanced control and operation of a DFIG-used back-to-back(BTB) PWM voltage source converter(VSC) are proposed. The modified control design for the grid-side converter in the stationary αβ frames diminishes the amplitude of DC-link voltage ripples of twice the grid frequency,and the two proposed control targets for the rotor-side converter are alternatively achieved,which,as a result,improve the fault-ride through(FRT) capability of the DFIG based wind power generation systems during unbalanced network supply. A complete unbalanced control scheme with both grid-and rotor-side converters included is designed. Finally,simulation was carried out on a 1.5 MW wind-turbine driven DFIG system and the validity of the developed unified model and the feasibility of the proposed control strategies are all confirmed by the simulated results. 相似文献
6.
This letter presents a multi-frequency proportional-resonant (MFPR) current controller developed for PWM voltage source converter (VSC) under the unbalanced supply voltage conditions. The delta operator is used in place of the shift operator for the implementation of MFPR by using a low-cost fixed-point DSP. The experimental results with an alternative control strategy validated the feasibility of the proposed MFPR current controller for the PWM VSC during voltage unbalance. 相似文献
7.
Multi-frequency proportional-resonant （MFPR） current controller for PWM VSC under unbalanced supply conditions 总被引：1，自引：0，他引：1
HU Jia-bing HE Yi-kang 《浙江大学学报(A卷英文版)》2007,8(10):1527-1531
This letter presents a multi-frequency proportional-resonant （MFPR） current controller developed for PWM voltage source converter （VSC） under the unbalanced supply voltage conditions. The delta operator is used in place of the shift operator for the implementation of MFPR by using a low-cost fixed-point DSE The experimental results with an alternative control strategy validated the feasibility of the proposed MFPR current controller for the PWM VSC during voltage unbalance. 相似文献
8.
ＩＮＴＲＯＤＵＣＴＩＯＮＰＦＣｃｉｒｃｕｉｔｒｙｓｉｍｕｌａｔｉｏｎｈａｓｓｏｍｅｉｎｈｅｒｅｎｔｄｉｆｆｉｃｕｌｔｉｅｓ,ａｓｔｗｏｆｒｅｑｕｅｎｃｉｅｓｈａｖｅｔｏｂｅｃｏｎ ｓｉｄｅｒｅｄｄｕｒｉｎｇｓｉｍｕｌａｔｉｏｎ :ｏｎｅｉｓｔｈｅｓｗｉｔｃｈｉｎｇｆｒｅｑｕｅｎｃｙｏｆａｂｏｕｔ 50ｋＨｚ,ａｎｏｔｈｅｒｉｓｔｈｅｍａｉｎｓｆｒｅｑｕｅｎｃｙｏｆ50ｔｏ 60Ｈｚ.Ｉｔｃａｕｓｅｓａｎｅｘｔｒｅｍｅｌｙｌａｒｇｅｄｙｎａｍｉｃｏｐｅｒａｔｉｏｎｒａｎｇｅ .Ｔｏｓｕｒｍｏｕｎｔｔｈｅｓｅｄｉｆ… 相似文献
9.
With the use of this novel everage model for Single Stage Flyback PFC+Flyback DC/DC converter, voltage control mode, peak
current control mode and average current control mode can be simulated easily by changing the model's parameters. It can be
used to do various analysis not only for small signal and static behavior but also for large signal and dynamic behavior of
the converter. By using this average model the simulation speed can be improved by 2 orders of magnitude above that obtained
by using the conventional switched model. It can be applied to optimize the trade-off between high power factor, voltage stress,
current stress and good output performance while designing this kind of single stage PFC converter. A 60W single stage power
factor corrector was built to verify the proposed model. The modeling principle can be applied to other Single Stage PFC topologies.
Project (No. 50077020) supponted by the National Natural Science Foundation of China. 相似文献
10.
GAO Chao 《重庆大学学报(英文版)》2008,7(2):119-124
A new family of converters, high-performance AC/DC power factor correction （PFC） switching converters with onecycle control technology and active floating-charge technology, was derived and experimentally verified. The topology of a single-phase CCM and DCM Boost-PFC switching converter was also analyzed. Its operating prniciples and control methods were expounded. Based on these, a new type of AC/DC switching converter circuits for PFC combined with one-cycle control technology was presented herein. The proposed AC/DC switching converter significantly helps improve the converter efficiency and its power factor value. 相似文献
11.
12.
高潮 《深圳信息职业技术学院学报》2007,5(1):24-28
本文通过对各种串并联谐振DC-DC开并变流器和输出整流器的比较,阐述了在分布式电源系统中,在DC-DC原边变流器中采用串并联谐振LLC谐振变流器和输出端采用全波整流器电路,在高输入电压的情况下,循环能量减小,输入电压范围可以拓宽,并且效率可以提高,损耗可明显减小。本文对串并联谐振谐振变换器的工作原理和控制方法进行了细致的分析,建立了谐振变换器的各个工作模式的条件,并给出了计算机仿真实验分析数据。 相似文献
13.
提出一种基于双蓄电池储能系统的电压分层协调控制策略,以储能系统为主体协调控制母线电压稳定。根据母线电压的变化范围将系统的动态调节过程划分为稳态阶段与暂态阶段。稳态阶段下,采用双蓄电池组共同协调工作方式,解决了负载突变导致单组蓄电池充放电电流过大,易引起过流故障的问题;暂态阶段下,采用基于改进下垂控制的双蓄电池组轮换协调工作方式,解决了单组蓄电池荷电状态(State of Charge,SOC)达到上、下限后,出现过充或过放情况引起的蓄电池损坏问题。利用Matlab/Simulink平台分别对系统的两种动态调节过程进行仿真,验证各阶段下所提出的工作方式的有效性,并通过单、双蓄电池组的对比,验证所提出控制策略的合理性与优越性。 相似文献
14.
This paper presented a control design methodology for a proton exchange membrane fuel cell （PEMFC） generation system for residential applications. The dynamic behavior of the generation system is complex in such applications. A compre- hensive control design is very important for achieving a steady system operation and efficiency. The control strategy for a 60 kW generation system was proposed and tested based on the system dynamic model. A two-variable single neuron proportional-integral （PI） decoupling controller was developed for anode pressure and humidity by adjusting the hydrogen flow and water injection. A similar controller was developed for cathode pressure and humidity by adjusting the exhaust flow and water injection. The desired oxygen excess ratio was kept by a feedback controller based on the load current. An optimal seeking con- troller was used to trace the unique optimal power point. Two negative feedback controllers were used to provide AC power and a suitable voltage for residential loads by a power conditioning unit. Control simulation tests showed that 60 kW PEMFC generation system responded well for computer-simulated step changes in the load power demand. This control methodology for a 60 kW PEMFC generation system would be a competitive solution for system level designs such as parameter design, performance analysis, and online optimization. 相似文献
15.
Voltage source converter high-voltage direct current （VSC-HVDC） is a new power transmission technology pref- erable in small or medium power transmission. In this paper we discuss a new control system based on space vector modulation （SVM） without any voltage line sensors. Using direct power control （DPC） SVM and a new double synchronous reference frame phase-locked loop （DSRF-PLL） approach, the control system is resistant to the majority of line voltage disturbances. Also, the system response has accelerated by using a feed forward power decoupled loop. The operation of this control strategy was verified in a SIMULINK/MATLAB simulation environment. To validate this control system, a 5 kV.A prototype system was constructed. Compared to the original controllers, the current total harmonic distortion （THD）, the active and reactive deviations and the DC voltage overshoot were lowered by 2.5%, 6.2% and 8%, respectively. The rectifier power factor in the worst condition was 0.93 and the DC voltage settling time was 0.2 s. 相似文献
16.
张圣杰 《荆门职业技术学院学报》2010,25(5):12-15
文章首先分析了Boost变换器的电压型、峰值电感电流型控制方法的原理,并在此基础上引入负载电流负反馈控制,构建Boost变换器的一种多环控制方法,分析了该方法的原理,并基于PSIM建立了仿真模型。仿真结果表明,多环控制的Boost变换器具有较好的动态特性。 相似文献
17.
This paper proposes an analysis and a direct power control （DPC） design of a wind turbine driven doubly-fed induction generator （DFIG） under unbalanced network voltage conditions. A DFIG model described in the positive and negative synchronous reference frames is presented. Variations of the stator output active and reactive powers are fully deduced in the presence of negative sequence supply voltage and rotor flux. An enhanced DPC scheme is proposed to eliminate stator active power oscillation during network unbalance. The proposed control scheme removes rotor current regulators and the decomposition processing of positive and negative sequence rotor currents. Simulation results using PSCAD/EMTDC are presented on a 2-MW DFIG wind power generation system to validate the feasibility of the proposed control scheme under balanced and unbalanced network conditions. 相似文献
18.
A novel direct-drive type wind power generation system based on hybrid excitation synchronous machine (HESM) is introduced
in this paper. The generator is connected to an uncontrollable rectifier, and a fully controlled voltage-source inverter is
used to connect the system to utility grid. An intermediate DC bus exists between the rectifier and inverter. A new control
strategy is proposed which achieves the maximum power point tracking (MPPT) with the control of excitation current of HESM
and stabilizes the DC link voltage with the control of inverter output current simultaneously. Specially-designed buck circuit
is used to control the excitation current of HESM, and grid voltage-oriented vector control strategy is employed to realize
the decoupling of the inverter output power. Simulation results and experiment in 3 kW lab prototype show an excellent static
and dynamic performance of the proposed system. 相似文献
19.
介绍了一种可以用于三相不对称负载的光伏正弦波逆变电源,该系统采用了TI公司生产的TMS320LF2407 DSP作为主控芯片,通过输出电流瞬时值反馈与电压平均值反馈控制将直流电逆变为标准的三相正弦波交流电。 相似文献
20.
本文提出了一种LCL谐振式推挽电路拓扑,谐振元件位于推挽电路变压器的原边;分析了电路的两种工作模式,通过分析可知,谐振电路参数决定谐振频率,同时影响谐振电流幅值;以600W样机为基础,进行了仿真分析与实验,实验表明提出的电路拓扑很好地实现了零电压开通和零电流关断,验证了拓扑的正确性和有效性。 相似文献