Power System Frequency Regulation Strategy with Participation of Hybrid Heterogeneous Flexible Loads
Duanchao Li, Jindian Lu, Li Zhang, Wei Wang, Zhuang Shi, Wanghao Wu, Feixiang Peng, Jun TaoIntroduction:
In "dual-high" power systems, frequency stability is challenged by declining rotational inertia. Frequent extreme high-temperature weather has increased the load of inverterbased air conditioners (IACs), which, along with electric vehicles (EVs), offer significant potential for frequency regulation due to their thermal inertia and power flexibility. To address the limitations of single-resource regulation and the idealized neglect of user comfort, this paper proposes a coordinated frequency regulation strategy integrating heterogeneous flexible loads.
Methods:
Based on traditional frequency models, an IAC model incorporating the Predicted Mean Vote (PMV) index is developed to assess thermal comfort-constrained regulation potential. Simultaneously, an EV frequency response model is established by evaluating behavior parameters and State of Charge (SOC) requirements.
Results:
Simulations demonstrate that stricter thermal comfort requirements reduce IAC regulation capacity. Similarly, EV regulation potential decreases as the scheduling time approaches the expected departure time. Compared with the conventional frequency-regulation scheme and the single flexible-load response scheme, the proposed hybrid heterogeneous-load frequency-response scheme can mitigate frequency deviation and achieve faster frequency recovery.
Discussion:
The results indicate that coordinated participation of IACs and EVs can effectively share frequency regulation tasks with thermal units, reduce frequency nadir deviation, and accelerate frequency recovery. Moreover, the comfort-constrained IAC model and SOC-constrained EV model demonstrate that ignoring user requirements may overestimate the practical regulation capacity of demand-side resources.
Conclusion:
The coordinated strategy of heterogeneous flexible loads outperforms single-resource schemes, significantly reducing frequency offsets and accelerating recovery. This approach effectively supports system stability while mitigating the operational pressure on thermal units.