• Journal of the Korea Convergence Society
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• v.2 no.3
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• pp.15-23
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• 2011

This paper deals with the analysis for the operation characteristic of PV 3 phase inverter, considering the state equation through d-q coordinates transformation, and proposes an algorithm of controlling current using PI(Proportional Integral) controller to control the output and the theory algorithm of sinusoidal PWM method to design inverter. And also this paper performs PV modelling using PSCAD/EMTDC S/W which is commonly used in analysis of distribution system and confirms effectiveness of the modelling proposed in this paper by analyzing and comparing the EMTDC/PSCAD simulation result with the theoretical method.

• KEPCO Journal on Electric Power and Energy
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• v.2 no.2
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• pp.253-257
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• 2016

This paper analyzes voltage control method in order to supply high-quality power for stand-alone microgrid. Stand-alone microgrid is composed of battery bank, stand-alone PCS and controllable loads. The main role of stand-alone PCS is to supply high-quality power to loads as main source by using stable voltage method regardless of load conditions. In particularly, output voltage of stand-alone PCS gets severely unbalanced voltage under unbalanced loads. Fundamental positive and negative sequences are transformed by two coordinates transformation which are rotated in each opposite direction, respectively. Each fundamental d-q voltage is regulated by each fundamental PI control. In addition, low-order harmonics are compensated through resonant controllers. Performance of stand-alone microgrid is tested for feasibility, and it is verified that output voltage of THD is improved to 1% from 2.2% under 50 kW balanced load, and is improved to 1.1% from 2.6% under 50 kW unbalanced load.