The 30th Annual Conference of the IEEE Industrial Electronics Society, November 2 - 6,2004, Busan, Korea Automatic Voltage Regulator Using a Novel Phase-Shifted PWM Single-phase Inverter *Kuo-Kai Shy *Ming-Ji Yang Jing-Heng Hong **Bau-Hung Lin *Department of Electrical Engineering, National Central University, E-mail : [email protected]**Department of research and development, RIYE Electric CO., LTD -mail : [email protected]Absfract-In this paper, a novel phase-shifted pulse width modulation (PS-PWM automatic voltage regulator (Am) with fast voltage control and reduced total harmonics is proposed The novel PS-PWM AVR is made up of an AUAC converter w t h reversible voltage control and a transformer for series voltage compensation. In the active rectifier, a proper switching operation is achieved w ithout the problem of power factor correction. The AVR uses a fully digital controller, which is implemented by a fixed-point digital signal processor DSP) TMS320F240 DSP-based board. Therefore, the proposed AVR gives high efficiency and reliability. It is also shown via some experimental results that the presented novel PS-PWM AVR gives good performance for high quality of the output voltage. Index Terms- PS-PWM AVR, AC/AC converter, DSP, active rectifier I. INTRODUCTION With the modem industry advance day by day, he production equipments o f automation become more and more precise. So the requirement of power quality becomes higher. Power quality problems commonly face industrial operations including transients, sags, swells, surges, outages, harmon ics, and impulses that vary in quantity or magnitude of the voltage. Of these, voltage sags and extended undervoltages have the largest negative impact on industrial productivity, and could be the most important factors of power quality variation for many industrial and commercial customers. Therefore, the automatic voltage regulator AVR) of high stability, wide voltage regulation ran ge, and fas t dynamic response is required to compensate for the fault of power quality. The conventional voltage regulator mainly has used servomotor to change the tap-changing transforme r. But the faults are as follows: large size of the mechanism, slower dynamic response, mechanical attrition and lower effic ienc y etc. Therefore, the conventional voltage regulator cannot be used i n precision equipment. In recent years, development of the AC voltage-voltage Converter and AC chopper has been used in AVR [ 11-[7]. There are two typical configurations f such AVR. First, the circuit configuration is an AC voltage-voltage converter (AC Buck) type. Even though most faults of the conventional voltage regulator could be improved by AC Buck, but it cannot level down the AC line voltage when the AC line has occurred some situations, such as swell, surge or long-term overvoltage. Secondary, the circuit configuration is a novel AC chopper [Z]. It not only improves the problem of conventional voltage regulator but also has voltage upldown capability. But its switching sk-itegy cannot reduce total harmonic distortion, switching loss and the size of the LC filter. Therefore, a novel switching strategy for single-phase voltage regulator is proposed in this study. The proposed switching strategy c n reduce switching loss, total harmonic distortion, size o f he LC filter etc, and then increases the performance of the single-phase voltage regulator. JIDESCFUPTION O F THE VOLTAGE REGULATOR TOPOLOGY In this paper , the proposed voltage regulator topology is shown i n Fig. 1 . Tn order to provide a stable AC power suppl y, the transformer series in between the AC line and the load side to compensate the variable voltage AC The of is making AC line from unstable to stable voltage, after the line voltage is regulated and controlled by power circuit and digital controller. Fig. 2 shows the voltage regulator topolo gy, the output voltage of load is given by v = v ./;G where vi is the unstable input, V , is the stable output, Y o s the output of the AC/AC converter, and s ratio of transformer. I \ i t v AC/AC Converter Fig. 1. When the AC line input terminal has occurred voltage variation, the load terminal still outpu ts a stable voltage after regulating the AC/AC converter. It can be noted that the power specification of AC/AC converter is reduced to IN of the output power because of using a hnsfor mer. Tha t is, Topology of the proposed novel PS-PWM AVR where output power, and N s the turns ratio of the transformer. is the power of the AClAC converter, Po,, is the 0-7803-8730-9/04/ 20.00 2004 EEE 1851
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Automatic Voltage Regulator Using a Novel Phase-Shifted PWM Single-phase Inverter
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7/21/2019 Automatic Voltage Regulator Using a Novel Phase-Shifted PWM Single-phase Inverter