Improved frequency regulation on hybrid wind-diesel microgrids using self-sensing electric thermal storage devices

Frequency regulation is central to the successful operation of remote wind-diesel powered electrical grids. Use of secondary or “dump” loads are necessary to allow instantaneous wind generation to exceed grid demand. The present study investigates the feasibility of using a network of Electric Thermal Storage (ETS) units without centralized control as an effective secondary load. Individual ETS units respond to changes in grid frequency by activating an appropriate number of heating elements in order to absorb energy surplus during high wind events. It is shown through numerical modelling that there are four major parameters that affect the response of the system: 1) zero-order hold time 2) full response point 3) number of units per phase, and 4) switching method. The effect of these parameters on frequency and voltage regulation is explored. When properly tuned, the ETS network can improve frequency and voltage regulation in wind-diesel mode.