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针对逆变器电流环的有功电流和无功电流存在耦合的情况,文中采用电流的解耦控制,达到独立控制逆变器的有功功率和无功功率;针对逆变器直流侧电压容易波动,文中采用双环控制,稳定逆变器直流侧的电压。搭建了MA-TALAB/SIMULINK系统仿真实验平台,通过间歇性能源输入逆变器功率变化的实验,验证了该逆变器能独立控制输出的有功功率和无功功率,并且保证了直流侧电压的稳定。 相似文献
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Parallel processing inverter system 总被引:5,自引:0,他引:5
Kawabata T. Sashida N. Yamamoto Y. Ogasawara K. Yamasaki Y. 《Power Electronics, IEEE Transactions on》1991,6(3):442-450
A novel method of instantaneous voltage and power balance control of a parallel processing inverter system is proposed. It consists of a high-speed switching PWM (pulsewidth modulated) inverter with an instantaneous current minor loop controller, a voltage major loop controller, and a power balance controller. This system realizes the following functions with only one inverter: constant AC output voltage control with reactive power control, active filtering to absorb load current harmonics, DC voltage and current control as AC-to-DC converter, and uninterruptible power supply (UPS) for stand-alone operation. This system covers a wide application range, including UPS systems, new energy systems, and active filters with voltage control functions 相似文献
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Output Impedance Design of Parallel-Connected UPS Inverters With Wireless Load-Sharing Control 总被引:8,自引:0,他引:8
《Industrial Electronics, IEEE Transactions on》2005,52(4):1126-1135
This paper deals with the design of the output impedance of uninterruptible power system (UPS) inverters with parallel-connection capability. In order to avoid the need for any communication among modules, the power-sharing control loops are based on the$P/Q$ droop method. Since in these systems the power-sharing accuracy is highly sensitive to the inverters output impedance, novel control loops to achieve both stable output impedance and proper power balance are proposed. In this sense, a novel wireless controller is designed by using three nested loops: 1) the inner loop is performed by using feedback linearization control techniques, providing a good quality output voltage waveform; 2) the intermediate loop enforces the output impedance of the inverter, achieving good harmonic power sharing while maintaining low output voltage total harmonic distortion; and 3) the outer loop calculates the output active and reactive powers and adjusts the output impedance value and the output voltage frequency during the load transients, obtaining excellent power sharing without deviations in either the frequency or the amplitude of the output voltage. Simulation and experimental results are reported from a parallel-connected UPS system sharing linear and nonlinear loads. 相似文献
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Control Strategy for Series and Parallel Output Dual-Buck Half Bridge Inverters Based on DSP Control
《Power Electronics, IEEE Transactions on》2009,24(2):434-444
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Wireless-Control Strategy for Parallel Operation of Distributed-Generation Inverters 总被引:5,自引:0,他引:5
Guerrero J.M. Matas J. Garcia De Vicunagarcia De Vicuna L. Castilla M. Miret J. 《Industrial Electronics, IEEE Transactions on》2006,53(5):1461-1470
In this paper, a method for the parallel operation of inverters in an ac-distributed system is proposed. This paper explores the control of active and reactive power flow through the analysis of the output impedance of the inverters and its impact on the power sharing. As a result, adaptive virtual output impedance is proposed in order to achieve a proper reactive power sharing, regardless of the line-impedance unbalances. A soft-start operation is also included, avoiding the initial current peak, which results in a seamless hot-swap operation. Active power sharing is achieved by adjusting the frequency in load transient situations only, owing to which the proposed method obtains a constant steady-state frequency and amplitude. As opposed to the conventional droop method, the transient response can be modified by acting on the main control parameters. Linear and nonlinear loads can be properly shared due to the addition of a current harmonic loop in the control strategy. Experimental results are presented from a two-6-kVA parallel-connected inverter system, showing the feasibility of the proposed approach 相似文献
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Current Weighting Distribution Control Strategy for Multi-Inverter Systems to Achieve Current Sharing 总被引:1,自引:0,他引:1
Wu T.-F. Wu Y.-E. Hsieh H.-M. Chen Y.-K. 《Power Electronics, IEEE Transactions on》2007,22(1):160-168
A current-weighting-distribution-control (CWDC) strategy for multi-inverter systems to achieve current sharing is presented in this paper. With a CWDC strategy, the inverters connected in parallel are allowed to have different power ratings and can achieve a weighted output current distribution by adding only simple circuits to each inverter. In such systems, each inverter has an outer voltage loop controller to govern system stability, an inner current loop controller to expedite dynamic response, and a weighting current controller to achieve current distribution and to reduce possible interactive effects among inverters. Experimental results from a two-inverter system and a three-inverter system have demonstrated the feasibility of the proposed strategy in weighting current distribution and fast regulation during a step-load change or hot-swap operation 相似文献
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Power Injection System for Grid-Connected Photovoltaic Generation Systems Based on Two Collaborative Voltage Source Inverters 总被引:1,自引:0,他引:1
Romero-Cadaval E. Milanes-Montero M.I. Gonzalez-Romera E. Barrero-Gonzalez F. 《Industrial Electronics, IEEE Transactions on》2009,56(11):4389-4398
This paper presents a new topology for the power injection system that is based on the parallel association of two voltage source inverters. One operates using a quasi-square voltage waveform strategy, and the other operates with a pulsewidth-modulation (PWM)-based strategy. The aims of this topology are to inject the power from the photovoltaic generation system using the quasi-square inverter and to control the current quality using the PWM inverter. The proposal optimizes the system design, permitting the reduction of system losses and an increase of the energy injected into the grid. 相似文献
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An accurate nonlinearity compensation technique for voltage source inverter (VSI) inverters is presented in this paper. Because of the nonlinearity introduced by the dead time, turn-on/off delay, snubber circuit and voltage drop across power devices, the output voltage of VSI inverters is distorted seriously in the low output voltage region. This distortion influences the output torque of IM motors for constant V/f drives. The nonlinearity of the inverter also causes 5th and 7th harmonic distortion in the line current when the distributed energy system operates in the grid-connected mode, i.e., when the distributed energy system is parallel to a large power system through the VSI inverter. Therefore, the exact compensation of this nonlinearity in the VSI inverter over the entire range of output voltage is desirable. In this paper, the nonlinearity of VSI inverter output voltage and the harmonic distortion in the line current are analyzed based on an open-loop system and a L-R load. By minimizing the harmonic component of the current in a d-axis and q-axis synchronous rotating reference frame, the exact compensation factor was obtained. Simulations and experimental results in the low frequency and low output voltage region are presented. 相似文献
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Combination voltage-controlled and current-controlled PWM invertersfor UPS parallel operation 总被引:1,自引:0,他引:1
Jiann-Fuh Chen Ching-Lung Chu 《Power Electronics, IEEE Transactions on》1995,10(5):547-558
In this paper, a scheme of combination of voltage-controlled and current-controlled PWM inverters for parallel operation of a single-phase uninterruptible power supply (UPS) is proposed. The voltage-controlled PWM inverter (VCPI) unit as a master is developed to keep a constant sinusoidal wave output voltage. The current-controlled PWM inverter (CCPI) units are operated as slave controlled to track the distributive current. The power distribution center (PDC) performs the function of distributing the output current of each active unit. In this proposed scheme of parallel operation, each of the units can be designed as nearly independent, and the CCPI units do not need a PLL circuit for synchronization. As a result, the parallel operation of UPS is easy to implement and to expand system capacity. For the purpose of illustration, the system, including three single-phase units which operate in parallel, is analyzed and experimental results are given 相似文献
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《Industrial Electronics, IEEE Transactions on》2008,55(11):3865-3873
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A new hybrid active power filter (APF) topology 总被引:12,自引:0,他引:12
In this paper, a new hybrid active power filter topology is presented. A higher-voltage, low-switching frequency insulated gate bipolar transistor (IGBT) inverter and a lower-voltage high-switching frequency metal oxide semiconductor field effect transistor (MOSFET) inverter are used in combination to achieve harmonic current compensation. The function of the IGBT inverter is to support utility fundamental voltage and to compensate for the fundamental reactive power. The MOSFET inverter fulfills the function of harmonic current compensation. To further reduce cost and to simplify control, the IGBT and MOSFET inverters share the same DC-link via a split capacitor bank. With this approach harmonics can be cancelled over a wide frequency range. Compared to the conventional APF topology, the proposed approach employs lower dc-link voltage and generates less noise. Simulation and experimental results show that the proposed active power filter topology is capable of compensating for the load harmonics 相似文献
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针对光伏并网逆变器并网后其本质上为电流源的特点,采用STM32F103VET6型ARM芯片作为系统的控制核心,制造了一台5 kW单相光伏并网型逆变器。采用了固定开关频率的电流瞬时值控制技术来实现对并网电流的控制,在控制策略中加入了电压前馈来抑制电网电压对逆变器输出电流的影响,使用二阶电流预估来抵消SPWM波形延时对系统控制的影响。并且优化了最大功率点跟踪(MPPT)。实验证明,该逆变器样机性能完全达到设计要求。 相似文献
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Savary Pierre Nakaoka Mutsuo Maruhashi Toru 《Industrial Electronics, IEEE Transactions on》1987,(2):247-256
The authors introduce a new configuration of resonant-type high-frequency inverter having inherent fast control response of the output power and variable-voltage variable-frequency (VVVF) capability. The circuit is composed of a parallel combination of two series-resonant inverters with common input and output terminals. Both inverter units are operated at synchronous frequency and with an adjustable phase difference from 0° to 180°, allowing control of the output power from full to null power, respectively. Operation of this inverter is explained and computer-simulated operating waveforms and characteristic curves are shown in terms of normalized control variables and circuit parameters. A prototype inverter using Power MOSFET modules has been originally tested with a high-frequency induction heating and melting load to demonstrate experimentally the proposed control principle and the steady-state inverter performances under parallel tuned load conditions. 相似文献
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Topologies of single-phase inverters for small distributed power generators: an overview 总被引:4,自引:0,他引:4
Yaosuo Xue Liuchen Chang Sren Baekhj Kjaer Bordonau J. Shimizu T. 《Power Electronics, IEEE Transactions on》2004,19(5):1305-1314
This paper presents an overview of single-phase inverters developed for small distributed power generators. The functions of inverters in distributed power generation (DG) systems include dc-ac conversion, output power quality assurance, various protection mechanisms, and system controls. Unique requirements for small distributed power generation systems include low cost, high efficiency and tolerance for an extremely wide range of input voltage variations. These requirements have driven the inverter development toward simpler topologies and structures, lower component counts, and tighter modular design. Both single-stage and multiple-stage inverters have been developed for power conversion in DG systems. Single-stage inverters offer simple structure and low cost, but suffer from a limited range of input voltage variations and are often characterized by compromised system performance. On the other hand, multiple-stage inverters accept a wide range of input voltage variations, but suffer from high cost, complicated structure and low efficiency. Various circuit topologies are presented, compared, and evaluated against the requirements of power decoupling and dual-grounding, the capabilities for grid-connected or/and stand-alone operations, and specific DG applications in this paper, along with the identification of recent development trends of single-phase inverters for distributed power generators. 相似文献
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Kazmierczuk M.K. Czarkowski D. Thirunarayan N. 《Industrial Electronics, IEEE Transactions on》1993,40(6):542-552
A phase-controlled resonant converter was obtained by connecting in parallel the AC loads of two identical parallel resonant inverters. A phase shift between the drive signals of the two inverters controls the amplitude of the output voltage of the new inverter. A voltage-driven rectifier is used as an AC load of the inverter, which results in a phase-controlled parallel resonant DC-DC converter. A frequency-domain analysis is performed for the steady-state operation of the inverter, and two types of voltage-driven rectifiers and design equations are derived. The converter can be operated at a constant switching frequency, which reduces EMI problems. It is found that for switching frequencies higher than the resonant frequency by a factor of 1.07, the load of each switching leg is inductive. The converter is capable of regulating the output voltage in the range of load resistance from full-load to no-load. Experimental results are presented for a prototype of the phase-controlled parallel resonant converter with a center-taped rectifier tested at an output power of 50 W and a switching frequency of 116 kHz 相似文献