共查询到20条相似文献,搜索用时 15 毫秒
1.
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
2.
Suppression of line voltage related distortion in current controlled grid connected inverters 总被引:5,自引:0,他引:5
Abeyasekera T. Johnson C.M. Atkinson D.J. Armstrong M. 《Power Electronics, IEEE Transactions on》2005,20(6):1393-1401
The influence of selected control strategies on the level of low-order current harmonic distortion generated by an inverter connected to a distorted grid is investigated through a combination of theoretical and experimental studies. A detailed theoretical analysis, based on the concept of harmonic impedance, establishes the suitability of inductor current feedback versus output current feedback with respect to inverter power quality. Experimental results, obtained from a purpose-built 500-W, three-level, half-bridge inverter with an L-C-L output filter, verify the efficacy of inductor current as the feedback variable, yielding an output current total harmonic distortion (THD) some 29% lower than that achieved using output current feedback. A feed-forward grid voltage disturbance rejection scheme is proposed as a means to further reduce the level of low-order current harmonic distortion. Results obtained from an inverter with inductor current feedback and optimized feed-forward disturbance rejection show a THD of just 3% at full-load, representing an improvement of some 53% on the same inverter with output current feedback and no feed-forward compensation. Significant improvements in THD were also achieved across the entire load range. It is concluded that the use of inductor current feedback and feed-forward voltage disturbance rejection represent cost-effect mechanisms for achieving improved output current quality. 相似文献
3.
A Direct PWM Technique for a Single-Phase Full-Bridge Inverter Through Controlled Capacitor Charging
4.
Shih-Liang Jung Ying-Yu Tzou 《Power Electronics, IEEE Transactions on》1996,11(4):567-577
This paper presents a discrete sliding-mode control scheme with feedforward compensation for the closed-loop regulation of the pulse-width modulated (PWM) inverter used in an uninterruptible power supply (UPS). The proposed feedforward controller can effectively improve the tracking performance of the PWM inverter. In designing the sliding-mode controller, we have taken load disturbance into consideration to enhance the robustness of the PWM inverter. Moreover, the upper bound of the load disturbance under which the sliding condition can be maintained has also been derived. The sliding curve of the sliding-mode controller is designed such that the behavior of the controlled PWM inverter is optimal subject to the selected cost function. Due to the coordinate transformation proposed in this paper, only the output voltage needs to be measured as feedback for the purpose of closed-loop regulation. Simulation and experimental results are given to show the effectiveness of the proposed control scheme 相似文献
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6.
《Industrial Electronics, IEEE Transactions on》2009,56(9):3467-3476
7.
针对传统高频机型UPS存在可靠性较差、抗电流冲击能力弱等缺点[5],采用了一种集充电和逆变一体化的单相UPS拓扑结构,并利用DSP芯片TMS320F28062进行控制,有效解决了传统高频UPS存在的以上问题。系统所用元器件数量减少,控制环节简单。通过设计1kW样机并进行了试验,UPS在逆变模式下交流输出电压为220V,充电模式下直流输出电压为27.6V,验证了电路拓扑和软件结构的正确性。 相似文献
8.
基于FPGA的逆变控制系统的研究 总被引:1,自引:1,他引:0
在研究Delta变换型UPS拓扑结构的基础上,通过改进逆变器的控制方法,提出了一种基于现场可编程门阵列(FPGA)的SPWM控制器实现方案。该控制器具有载波、调制波的频率和幅度均可在线调节,死区时间可预置,并具有闭环调节功能等特点。整个电路通过FPGA芯片实现,采用硬件描述语言(VHDL)与原理图输入相结合的方法,完成了整个功能模块的设计,使得控制系统更加简单可靠。对所设计的控制器进行了功能和时序仿真,仿真结果验证了设计的正确性和可行性。 相似文献
9.
A boost DC-AC converter: analysis, design, and experimentation 总被引:20,自引:0,他引:20
This paper proposes a new voltage source inverter (VSI) referred to as a boost inverter or boost DC-AC converter. The main attribute of the new inverter topology is the fact that it generates an AC output voltage larger than the DC input one, depending on the instantaneous duty cycle. This property is not found in the classical VSI, which produces an AC output instantaneous voltage always lower than the DC input one. For the purpose of optimizing the boost inverter dynamics, while ensuring correct operation in any working condition, a sliding mode controller is proposed. The main advantage of the sliding mode control over the classical control schemes is its robustness for plant parameter variations, which leads to invariant dynamics and steady-state response in the ideal case. Operation, analysis, control strategy, and experimental results are included in this paper. The new inverter is intended to be used in uninterruptible power supply (UPS) and AC driver systems design whenever an AC voltage larger than the DC link voltage is needed, with no need of a second power conversion stage 相似文献
10.
A switch-mode DC-to-AC inverter based on a DC-to-DC converter topology using a novel nonlinear robust control to generate a sinusoidal output waveform is presented. The control scheme is based on simultaneous feedback of the output voltage and feedforward of the input voltage and inductor voltage. As a result, the output voltage remains dynamically unchanged when there are large disturbances in input voltage or load current. The nature of the control law is explained. Computer simulation results show the robustness and fast dynamical response of the control system. The experimental results are presented to verify the analysis and demonstrate the feasibility of the control strategy 相似文献
11.
Ying-Yu Tzou Rong-Shyang Ou Shih-Liang Jung Meng-Yueh Chang 《Power Electronics, IEEE Transactions on》1997,12(4):715-725
This paper proposes a new control scheme based on a two-layer control structure to improve both the transient and steady-state responses of a closed-loop regulated pulse-width-modulated (PWM) inverter for high-quality sinusoidal AC voltage regulation. The proposed two-layer controller consists of a tracking controller and a repetitive controller. Pole assignment with state feedback has been employed in designing the tracking controller for transient response improvement, and a repetitive control scheme was developed in synthesizing the repetitive controller for steady-state response improvement. A design procedure is given for synthesizing the repetitive controller for PWM inverters to minimize periodic errors induced by rectifier-type nonlinear loads. The proposed control scheme has been realized using a single-chip digital signal processor (DSP) TMS320C14 from Texas Instruments. A 2-kVA PWM inverter has been constructed to verify the proposed control scheme. Total harmonic distortion (THD) below 1.4% for a 60-Hz output voltage under a bridge-rectifier RC load with a current crest factor of 3 has been obtained. Simulation and experimental results show that the DSP-based fully digital-controlled PWM inverter can achieve both good dynamic response and low harmonics distortion 相似文献
12.
Minimum copper loss flux-weakening control of surface mounted permanent magnet synchronous motors 总被引:1,自引:0,他引:1
Jiunn-Jiang Chen Kan-Ping Chin 《Power Electronics, IEEE Transactions on》2003,18(4):929-936
This study presents a novel current loop design method capable of automatic flux-weakening control with minimum copper loss for surface mounted permanent magnet synchronous motors (SPMSM). The proposed current controller can automatically re-compute the d-axis current command to defer output voltage saturation. Consequently, the motor operations in the flux-weakening region are also contained in the stable operating region. Analysis results indicate that since the output voltage vector in the flux-weakening region produced by this controller is consistently on the boundary of the maximum output voltage vector allowed by the inverter, the corresponding flux-weakening current is the optimal value in the sense of minimum copper loss. This minimum copper loss design differs from the maximum output torque design and the constant power design of the flux-weakening control methods found in the literature. Experimental results further demonstrate the feasibility of the proposed current controller and its ability to maximize the speed range of the motor drive for a given inverter capacity. 相似文献
13.
Zbigniew Rymarski 《International Journal of Electronics》2013,100(5):521-535
This article presents the complete design of a low power voltage source inverter (VSI) dedicated for a UPS system. The analysis of the rectangular PWM-AC voltage spectrum allows for a choice of the basic architecture of the inverter. Output filter parameters were calculated to reduce the maximum amplitude of the output VSI voltage harmonics for the steady-state inverter mode. The choice of the feedback loop type was based on a discussion of the inverter output impedance using a continuous model of the inverter. The parameters of the inner loop digital control for the discrete inverter model were calculated using the Coefficient Diagram Method. The influence of the step load was modelled. The time constant of the inverter closed loop system was selected to ensure sufficient system robustness. An outer feedback loop with a plug-in repetitive controller, simplified owing to the properties of the PID/CDM inner loop control, was introduced to eliminate the periodic disturbances generated by the non-linear rectifier load and the deadtime influence. The experimental verification of the design method is presented. 相似文献
14.
An improved deadbeat control for UPS using disturbance observers 总被引:2,自引:0,他引:2
A digital control technique for the inverter stage of uninterruptible power supplies is proposed, which is based on a predictive regulator on both output voltage and inductor current. Its aim is to achieve a deadbeat dynamic response for the controlled variables (output voltage and inverter current). Besides the linear state feedback which allocates system poles at the origin so as to achieve deadbeat response for all state variables, the use of a disturbance observer for the estimation of the load current and of any other source of errors (such as dead-times, parameter, and model mismatches) is investigated. The proposed solution is able to guarantee a fast dynamic response and also a precise compensation of any source of unpredictable disturbance. Moreover, with a proper design of observer parameters, it is possible to reduce control sensitivity to model uncertainties, parameter mismatches, and noise on sensed variables, which usually characterizes existing deadbeat control techniques. Finally, the control algorithm is quite simple and requires only the measurements of the output voltage and inductor current. Experimental results on a single-phase 2 kVA prototype show the effectiveness of the proposed approach. 相似文献
15.
Sung-Jun Park Feel-Soon Kang Man Hyung Lee Cheul-U Kim 《Power Electronics, IEEE Transactions on》2003,18(3):831-843
A single-phase five-level PWM inverter is presented to alleviate harmonic components of the output voltage and the load current. Operational principles with switching functions are analyzed. To keep the output voltage sinusoidal and to have the high dynamic performances even in the cases of load variations and the partial magnetization in filter inductor, the deadbeat controller is designed and implemented on a prototype. The validity of the proposed inverter is verified through simulation and experiments. To assess the proposed inverter, it is compared with the conventional single-phase three-level PWM inverter under the conditions of identical supply DC voltage and switching frequency. In addition, it is compared with the five-level cascaded PWM inverter. 相似文献
16.
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
17.
This paper presents a new control technique for resonant converters. Unlike conventional variable frequency control which externally imposes the switching frequency, the proposed scheme is based on controlling the displacement angle between one of the resonant circuit variables, typically the current through the resonant inductor, and the voltage at the output of the inverter. As a result, zero-voltage switching (ZVS) can be ensured over a wide operating range. The proposed control technique cam be applied for series, parallel, and series-parallel resonant converters. As an example, the static characteristics and dynamic model of a series-parallel resonant converter with the proposed controller are derived and the system behaviour is investigated in detail. Experimental results are given to demonstrate the operation of resonant converters with the proposed controller and to validate the analysis 相似文献
18.
电压电流双环控制策略对单相逆变电源有一定的优越性,不同的采样电流方式对逆变电源输出电压外特性有着不同的影响。在控制参数一致的情况下进行对比分析,电感电流反馈方式对其输出电压外特性的影响较大,对并联逆变电源的环流影响较小;电容电流反馈对输出电压外特性的影响较小,对并联逆变电源的环流影响较小,所以文中并联系统采用电容电流反馈方式作为内环调节;通过MATLAB软件中的simulink工具验证了理论的正确性。 相似文献
19.
Boost DC-AC inverter: a new control strategy 总被引:6,自引:0,他引:6
Sanchis P. Ursaea A. Gubia E. Marroyo L. 《Power Electronics, IEEE Transactions on》2005,20(2):343-353
Boost dc-ac inverter naturally generates in a single stage an ac voltage whose peak value can be lower or greater than the dc input voltage. The main drawback of this structure deals with its control. Boost inverter consists of Boost dc-dc converters that have to be controlled in a variable-operation point condition. The sliding mode control has been proposed as an option. However, it does not directly control the inductance averaged-current. This paper proposes a control strategy for the Boost inverter in which each Boost is controlled by means of a double-loop regulation scheme that consists of a new inductor current control inner loop and an also new output voltage control outer loop. These loops include compensations in order to cope with the Boost variable operation point condition and to achieve a high robustness to both input voltage and output current disturbances. As shown by simulation and prototype experimental results, the proposed control strategy achieves a very high reliable performance, even in difficult transient situations such as nonlinear loads, abrupt load changes, short circuits, etc., which sliding mode control cannot cope with. 相似文献
20.
《Power Electronics, IEEE Transactions on》2009,24(5):1259-1266