Synergetic frequency response from multiple flexible loads

Flexible load is likely to be a key component of future systems with the potential to enhance overall system efficiency. Multiple flexible end uses can be utilised to provide system frequency sensitive reserves. However, consideration of inter/intra day end use variability is required when tuning the flexible load response to achieve acceptable frequency behaviour. To that end, a generic synergetic mechanism is presented for frequency based primary reserve provision using representative thermostatic and charging loads. Based on differing dynamic response and load availability patterns of flexible end uses, it aims to enhance the frequency response while avoiding frequency overshoots, and minimising communication requirements. Scheme validation involves a year-long contingency analysis with varying generation mix, system demand and flexible load scenarios. The results show a marked improvement in frequency nadirs, while avoiding frequency overshoots and avoiding contracted load shedding.