Enhancing Power Quality and Stability of Future Smart Grid with Intermittent Renewable Energy Sources Using Electric Springs

The concept of "electric spring" is recently proposed to enhance the stability of smart grid with intermittent renewable energy sources. Electric springs can be integrated into the non-critical electrical loads to form smart loads. The smart load has the characteristics of (i) following intermittent power generation by changing its load demand dynamically and (ii) regulating the voltage at the point in distribution system where it is connected. Therefore, it is projected as futuristic device to mitigate voltage fluctuation problems in future smart grid where large number of small scale intermittent renewable energy sources are connected. However, further research has shown that the full capability of smart loads has not been explored. Due to the presence of power electronic converter in smart load, it also has the potential of improving power quality of the supply voltage by reducing voltage harmonics. In this paper, an enhanced control algorithm for smart load is proposed to add the feature of improving power quality of the supply voltage over and above aforementioned characteristics.