Reactive Power Limiting at TSO-DSO Interface using Distribution Flexibility

A vast integration of distributed energy resources at the distribution level has emerged the system security issues such as voltage and frequency control for system operators. TSO and DSO have to initiate new grid policies to increase the coordination among the system operators. One of the needs for coordination is reactive power provision at the T-D interface to mitigate the probability of voltage violations. This manuscript proposes a new method to aggregate the reactive power at the T-D interface considering grid network and operational constraints using the distribution side flexibility. The impact of demand and Q/P ratio on the reactive power transfer is investigated to simulate the high DER integrated scenario. Results are validated using the modified IEEE 33 bus system. Furthermore, the effect of the Q/P ratio on the voltage at the primary substation node is also illustrated. Overall, this manuscript proposes the idea of reactive power management at the T-D interface and their affecting factors using the coordination between TSO and DSO, which will provide the direction for new grid initiatives for system operators.