PWM rectifier

About: PWM rectifier is a research topic. Over the lifetime, 2254 publications have been published within this topic receiving 25614 citations.

PWM-rectifier/voltage-source inverter without DC link components for induction motor drive

Abstract: Voltage-source inverters are normally equipped with an electrolyte capacitor in their DC link. A voltage-source inverter without DC link components is proposed to eliminate the electrolytic capacitor which has a short life compared with an AC capacitor (metalised polyester film, etc.). This inverter system requires an AC filter composed of L and C in the AC source side. In this case, the most important problem is the reduction of AC filter capacity. To achieve this reduction, the rectifier section is operated by PWM control. The waveform of the AC source current is also improved. Steady-state analysis, the calculated characteristics of the AC filter capacity and the waveforms of voltage and current are described for a 0.75 kW induction motor driven by the system. The AC filter capacity is reduced to about 38% of the rectifier without PWM. Measured waveforms are presented for a motor slip of 4%. The stability with, and without, DC link components, is also discussed.

Fast-response high-quality rectifier with sliding mode control

Abstract: A PWM rectifier including an uncontrolled rectifier and a Cuk converter stage driven by a sliding mode controller is described. Like other high-quality rectifiers, this solution allows low-distorted and in-phase line current. Moreover, due to the sliding mode control, fast and stable response is achieved, in spite of the large output filter. Control complexity is the same as that of standard current-mode controls. Converter analysis, design criteria, and experimental results are reported. >

Design Considerations for Maintaining DC-Side Voltage of Hybrid Active Power Filter With Injection Circuit

Abstract: Hybrid active power filter with injection circuit (IHAPF) shows great promise in reducing harmonics and improving power factor with a relatively low capacity active power filter, but suffers from DC-side voltage instability that inadvertently impacts the compensation performance and safety of the IHAPF. In this paper, two new methods are proposed to overcome this major technical challenge with a hysteretic control and energy release circuit, and a controllable pulsewidth modulation (PWM) rectifier. Modeling, theoretical analysis, and experimental results have verified that both methods can stabilize DC-side voltage within a certain range. A prototype IHAPF system was built incorporating the PWM rectifier DC voltage control scheme, and installed in a 220 kV substation in Southern China. It demonstrated significant improvement in harmonics reduction and power factor. The DC voltage stability issue was also resolved with the new design.

Modeling, Modulation, and Control of the Three-Phase Four-Switch PWM Rectifier Under Balanced Voltage

Abstract: The modeling, modulation, and control of the three-phase four-switch (TPFS) PWM rectifier are investigated in this paper. Three space vector pulse width modulation methods using different equivalent zero vectors are developed, where sector identification and the trigonometric function are not required. Then, the high-frequency model for the current ripple analysis is proposed, and the effects of three SVM approaches on the ac current ripple are investigated. According to the analytical results, the method introducing the smallest current ripple is selected. With the optimized SVM approach, a control-oriented model, considering the capacitor voltage oscillation and deviation, is built in the dq synchronous frame to facilitate the controller design. Furthermore, a control strategy implementing the proportional controller is developed to eliminate the capacitor voltage deviation. Meanwhile, the dual-loop control of the TPFS is not affected by the proposed strategy as the capacitor voltage deviation is eliminated. Finally, a novel linear modulation index function is defined to reject the low-frequency harmonic current introduced by the overmodulation. Experimental results demonstrate that excellent current performance is achieved with comprehensive considerations of the modeling, modulation, and control strategy.

A simple maximum power point tracker for grid connected variable speed wind energy conversion system with reduced switch count power converters

Abstract: In this paper, a simple control strategy for an optimal extraction of output power from grid connected variable speed wind energy conversion system (VSWECS) with reduced switch count power converters is presented. In order to improve the overall efficiency and to reduce the cost, B-4 PWM converters are used. The system consists of a variable speed wind turbine coupled to a permanent magnet synchronous generator (PMSG) through a gear box, two PWM B4-power converters. Output power from PMSG is first converted into DC and then it is fed to the grid. Both the power conversions are performed at unity power factor and the DC link voltage is maintained constant. The MPPT extracts optimum power from the wind turbine from cut-in to rated wind velocity by sensing only the turbine output power. The complete system has been simulated for various wind velocities. The control algorithm is implemented on TMS320F243 DSP and the simulated results are validated by experimental results.